Energy metabolism, body composition, and urea generation rate in hemodialysis patients.
Sridharan, Sivakumar; Vilar, Enric; Berdeprado, Jocelyn; Farrington, Ken
2013-10-01
Hemodialysis (HD) adequacy is currently assessed using normalized urea clearance (Kt/V), although scaling based on Watson volume (V) may disadvantage women and men with low body weight. Alternative scaling factors such as resting energy expenditure and high metabolic rate organ mass have been suggested. The relationship between such factors and uremic toxin generation has not been established. We aimed to study the relationship between body size, energy metabolism, and urea generation rate. A cross-sectional cohort of 166 HD patients was studied. Anthropometric measurements were carried on all. Resting energy expenditure was measured by indirect calorimetry, fat-free mass by bio-impedance and total energy expenditure by combining resting energy expenditure with a questionnaire-derived physical activity data. High metabolic rate organ mass was calculated using a published equation and urea generation rate using formal urea kinetic modeling. Metabolic factors including resting energy expenditure, total energy expenditure and fat-free mass correlated better with urea generation rate than did Watson volume. Total energy expenditure and fat-free mass (but not Watson Volume) were independent predictors of urea generation rate, the model explaining 42% of its variation. Small women (
Pan, Kelsey; Smith, Lindsey P.; Batis, Carolina; Popkin, Barry M.; Kenan, W.R.
2014-01-01
Objective We examined trends from 1991–2009 in total energy intake and food group intake, and examine whether shifts varied by age or generation. Design Longitudinal time series (1991, 1993, 1997, 2000, 2004, 2006, 2009) Setting Nine provinces in China Participants Older Chinese aged ≥60 years (n=5,068) from the China Health and Nutrition Survey from 1991–2009 Methods Using three 24-hour recalls and a household food inventory collected over three consecutive days, the top twenty food group contributors to total energy intake from 1991–2009 were identified, and the mean kilocalorie (kcal) difference between 1991 and 2009 for each food group was ranked. The top twenty food group contributors to total energy intake from 1991–2009 were identified, and the mean kilocalorie (kcal) difference between 1991 and 2009 for each food group was ranked. Linear regression was used to examine changes in mean calorie intake of food groups between 1991 and 2009, adjusting for age, sex, and region. In addition, we examined changes in the mean kcal per capita intake to examine shifts by age group and generation. Results Mean total energy intake increased significantly among older Chinese adults from 1379 total kilocalories in 1991 to 1463 kilocalories in 2009 (p< 0.001). Most food groups showed a significant increase in intake from 1991 to 2009, with plant oil, wheat buns, and wheat noodles showing the greatest increase. At the same age, more recent generations had more energy intake than earlier generations. An aging effect was observed, with energy intake decreasing with age, although more recent generations showed a smaller decrease in energy intake with aging. Conclusion Older Chinese adults in recent generations show an increase in total calorie intake compared to older Chinese of earlier generations, paired with a less significant decrease in calorie intake as they age. Increased consumption of high-fat, non-staple high-carbohydrate foods such as plant oil and wheat buns suggests that diet quality of older Chinese adults is becoming less healthful in recent years. PMID:25657984
Development and Application of an Approach to Optimize Renewable Energy Systems in Afghanistan
2012-06-01
upon renewable energy sources for power production , the more desirable the system design. Total operations and maintenance cost has the third...Engineers (USACE) practices for implementing energy systems for ANSF infrastructure are limited to diesel generators, and, thus, preclude alternative...system attribute values: total O&M cost, renewable fraction, generator production , wind production , solar production , battery quantity, life cycle
Potential for energy generation from anaerobic digestion of food waste in Australia.
Lou, Xian Fang; Nair, Jaya; Ho, Goen
2013-03-01
Published national and state reports have revealed that Australia deposits an average of 16 million Mg of solid waste into landfills yearly, of which approximately 12.6% is comprised of food. Being highly biodegradable and possessing high energy content, anaerobic digestion offers an attractive treatment option alternative to landfilling. The present study attempted to identify the theoretical maximum benefit of food waste digestion in Australia with regard to energy recovery and waste diversion from landfills. The study also assessed the scope for anaerobic process to utilize waste for energy projects through various case study scenarios. Results indicated anaerobic digestion of total food waste generated across multiple sites in Australia could generate 558 453 dam(3) of methane which translated to 20.3 PJ of heating potential or 1915 GWe in electricity generation annually. This would contribute to 3.5% of total current energy supply from renewable sources. Energy contribution from anaerobic digestion of food waste to the total energy requirement in Australia remains low, partially due to the high energy consumption of the country. However its appropriateness in low density regions, which are prevalent in Australia, may allow digesters to have a niche application in the country.
Relativistic analogue of the Newtonian fluid energy equation with nucleosynthesis
DOE Office of Scientific and Technical Information (OSTI.GOV)
Cardall, Christian Y.
In Newtonian fluid dynamics simulations in which composition has been tracked by a nuclear reaction network, energy generation due to composition changes has generally been handled as a separate source term in the energy equation. Here, a relativistic equation in conservative form for total fluid energy, obtained from the spacetime divergence of the stress-energy tensor, in principle encompasses such energy generation; but it is not explicitly manifest. An alternative relativistic energy equation in conservative form—in which the nuclear energy generation appears explicitly, and that reduces directly to the Newtonian internal+kinetic energy in the appropriate limit—emerges naturally and self-consistently from themore » difference of the equation for total fluid energy and the equation for baryon number conservation multiplied by the average baryon mass m, when m is expressed in terms of contributions from the nuclear species in the fluid, and allowed to be mutable.« less
Relativistic analogue of the Newtonian fluid energy equation with nucleosynthesis
Cardall, Christian Y.
2017-12-15
In Newtonian fluid dynamics simulations in which composition has been tracked by a nuclear reaction network, energy generation due to composition changes has generally been handled as a separate source term in the energy equation. Here, a relativistic equation in conservative form for total fluid energy, obtained from the spacetime divergence of the stress-energy tensor, in principle encompasses such energy generation; but it is not explicitly manifest. An alternative relativistic energy equation in conservative form—in which the nuclear energy generation appears explicitly, and that reduces directly to the Newtonian internal+kinetic energy in the appropriate limit—emerges naturally and self-consistently from themore » difference of the equation for total fluid energy and the equation for baryon number conservation multiplied by the average baryon mass m, when m is expressed in terms of contributions from the nuclear species in the fluid, and allowed to be mutable.« less
NASA Astrophysics Data System (ADS)
Song, Y.; Lysak, R. L.
2016-12-01
In previous theories (e.g., Hasegawa and Sato, 1979; Sato and Iijima, 1979; Vasyliunas, 1984), field-aligned current (FAC) generation is derived from current continuity assumption plus the force balance between the Lorentz force and other forces in the MHD momentum equation. These theories suggest that the FAC is generated by other forces, such as the inertia and/or pressure gradients. In fact, the FAC cannot be generated by these forces. From Maxwell's equations, FAC generation is associated with enhanced sheared magnetic fields and free magnetic energy where a dynamo action and Alfven waves are needed to generate and transport free magnetic energy. It is obvious that the mechanism of FAC generation cannot be given by analyzing a local force balance. We propose that FACs are generated by Alfvenic interactions in the M-I coupling driven system. From a full set of the dynamical equations, we have found that the generation of the total FAC (J||total ) is associated with spatial gradients of the parallel vorticity, where J||total=J||+J||D, and J||D=(1/4∏)(∂E||/∂t) is the displacement current, which describes E|| generation (Song and Lysak, 2006). The J||total generation is a dynamo process associated with the increase of the azimuthal magnetic flux caused by the axial torque acting on FAC flux tubes. Although the magnitude of the J||D is often very small relative to J||, neglecting this term, we cannot find the mechanism of the E|| generation. When the plasma density is low J||D becomes important relative to the current. We will demonstrate how the generation of E|| and the formation of auroral arcs can redistribute perpendicular mechanical and magnetic stresses which can cause a sudden and violent tail energy release and enhance the total FAC leading to the substorm auroral poleward expansion. We will also show how the nonlinear interaction of incident and reflected Alfven wave packets in the auroral acceleration region can produce quasi-stationary non-propagating electromagnetic plasma structures, such as Alfvenic double layers. These structures will sustain the J||D and can constitute powerful high energy particle accelerators, where electromagnetic energy can be efficiently converted to the particle energy.
Net energy output from harvesting small-diameter trees using a mechanized system
Fei Pan; Han-Sup Han; Leonard R. Johnson; William J. Elliot
2008-01-01
What amount of extra energy can be generated after subtracting the total energy consumed to produce the biomass energy? Knowing the ratio between energy output and input is a valid question when highly mechanized systems that consume fossil fuels are used to harvest and transport forest biomass for energy. We estimated the net energy generated from mechanical fuel...
Geothermal development in the Philippines
DOE Office of Scientific and Technical Information (OSTI.GOV)
Elizagaque, R.F.; Tolentino, B.S.
1982-06-01
The development of geothermal resources and energy in the Philippines is discussed. Philippine National Oil Company-Energy Development Corporation initiated the first semi-commercial generation of geothermal power in July 1977 with the installation of a 3MWe plant. By 1980 the country had 440 MWe on line at Mak-Ban and Tiwi. This placed the Philippines second after the US among countries using geothermal energy for power generation. Before the end of 1981, PNOC-EDC added 6 additional MWe of geothermal power generating capacity to increase the total to 446 MWe. As part of the five-year National Energy Development Programme covering the period 1981-1985,more » additional power plants will be installed in various project areas to increase the share of geothermal power generation from the present 9.8% to 18.6% of the nationwide power-generation total, or the equivalent of 16.6 million barrels of oil per year. (MJF)« less
76 FR 23230 - Segregation of Lands-Renewable Energy
Federal Register 2010, 2011, 2012, 2013, 2014
2011-04-26
... within the wind energy right-of- way application areas in FY 2009 and 2010, we estimate the total cost of... transmission facilities that could be used to carry the power generated from a specific wind or solar energy..., public lands included in a pending or future wind or solar energy generation right-of-way (ROW...
South Carolina | Midmarket Solar Policies in the United States | Solar
voluntary renewable energy goal of 2% distributed energy in 2021. Carve-out: 0.25% of total generation from energy portfolio standard, but a goal for distributed generation by 2021. The Distributed Energy Resource Fast Track Process Study Process System size limit: Not specified; South Carolina Public Service
NASA Technical Reports Server (NTRS)
Browning, P. A.; Fuelberg, H. E.
1983-01-01
Divergent and rotational components of the synoptic scale kinetic energy balance are presented using rawinsonde data at 3 and 6 h intervals from the Atmospheric Variability Experiment (AVE 4). Two intense thunderstorm complexes occurred during the period. Energy budgets are described for the entire computational region and for limited volumes that enclose and move with the convection. Although small in magnitude, the divergent wind component played an important role in the cross contour generation and horizontal flux divergence of kinetic energy. The importance of V sub D appears directly to the presence and intensity of convection within the area. Although K sub D usually comprised less than 10 percent of the total kinetic energy content within the storm environment, as much as 87 percent of the total horizontal flux divergence and 68 percent of the total cross contour generation was due to the divergent component in the upper atmosphere. Generation of kinetic energy by the divergent component appears to be a major factor in the creation of an upper level wind maximum on the poleward side of one of the complexes. A random error analysis is presented to assess confidence limits in the various energy parameters.
NASA Astrophysics Data System (ADS)
Ramirez Camargo, Luis; Dorner, Wolfgang
2016-04-01
The yearly cumulated technical energy generation potential of grid-connected roof-top photovoltaic power plants is significantly larger than the demand of domestic buildings in sparsely populated municipalities in central Europe. However, an energy balance with cumulated annual values does not deliver the right picture about the actual potential for photovoltaics since these run on a highly variable energy source as solar radiation. The mismatch between the periods of generation and demand creates hard limitations for the deployment of the theoretical energy generation potential of roof-top photovoltaics. The actual penetration of roof-top photovoltaic is restricted by the energy quality requirements of the grid and/or the available storage capacity for the electricity production beyond the coverage of own demands. In this study we evaluate in how far small-scale storage systems can contribute to increment the grid-connected roof-top photovoltaic penetration in domestic buildings at a municipal scale. To accomplish this, we calculate, in a first step, the total technical roof-top photovoltaic energy generation potential of a municipality in a high spatiotemporal resolution using a procedure that relies on geographic information systems. Posteriorly, we constrain the set of potential photovoltaic plants to the ones that would be necessary to cover the total yearly demand of the municipality. We assume that photovoltaic plants with the highest yearly yield are the ones that should be installed. For this sub-set of photovoltaic plants we consider five scenarios: 1) no storage 2) one 7 kWh battery is installed in every building with a roof-top photovoltaic plant 3) one 10 kWh battery is installed in every building with a roof-top photovoltaic plant 4) one 7 kWh battery is installed in every domestic building in the municipality 5) one 10 kWh battery is installed in every domestic building in the municipality. Afterwards we evaluate the energy balance of the municipality using a series of indicators. These indicators include: a) the total photovoltaic installed capacity, b) the total storage installed capacity, c) the output variability, d) the total unfulfilled demand, e) total excess energy, f) total properly supplied energy, g) the loss of power supply probability, h) the amount of hours of supply higher than the highest demand in a year, i) the number of hours, when supply is 1.5. times higher than the highest demand in a year, and j) the additional storage energy capacity and power required to store all excess energy generated by the photovoltaic installations. The comparison of the proposed indicators serves to quantify the contribution that household-sized small-scale storage systems would make to the energy balance of the studied municipality. Increased installed energy storage capacity allows a higher roof-top photovoltaic share and improves energy utilization, variability and reliability indicators. The proposed methodology serves also to determine the amount of storage capacity with the highest positive impact on the local energy balance.
Solar total energy project at Shenandoah, Georgia system design
NASA Technical Reports Server (NTRS)
Poche, A. J.
1980-01-01
The solar total energy system (STES) was to provide 50% of the total electrical and thermal energy requirements of the 25,000 sq ft Bleyle of America knitwear plant located at the Shenandoah Site. The system will provide 400 kilowatts electrical and 3 megawatts of thermal energy. The STES has a classical, cascaded total energy system configuration. It utilizes one hundred twenty (120), parabolic dish collectors, high temperature (750 F) trickle oil thermal energy storage and a steam turbine generator. The electrical load shaving system was designed for interconnected operation with the Georgia Power system and for operation in a stand alone mode.
Federal Register 2010, 2011, 2012, 2013, 2014
2011-11-21
... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Project No. 14244-000] KC Hydo LLC of... electrical generating equipment with total hydraulic capacity of 160 cubic feet per second (cfs) and total... D. Bose, Secretary, Federal Energy Regulatory Commission, 888 First Street, NE., Washington, DC...
Game theory competition analysis of reservoir water supply and hydropower generation
NASA Astrophysics Data System (ADS)
Lee, T.
2013-12-01
The total installed capacity of the power generation systems in Taiwan is about 41,000 MW. Hydropower is one of the most important renewable energy sources, with hydropower generation capacity of about 4,540 MW. The aim of this research is to analyze competition between water supply and hydropower generation in water-energy systems. The major relationships between water and energy systems include hydropower generation by water, energy consumption for water system operation, and water consumption for energy system. In this research, a game-theoretic Cournot model is formulated to simulate oligopolistic competition between water supply, hydropower generation, and co-fired power generation in water-energy systems. A Nash equilibrium of the competitive market is derived and solved by GAMS with PATH solver. In addition, a case study analyzing the competition among water supply and hydropower generation of De-ji and Ku-Kuan reservoirs, Taipower, Star Energy, and Star-Yuan power companies in central Taiwan is conducted.
Generation of 1.3 μm and 1.5 μm high-energy Raman radiations in α-BaTeMo2O9 crystals
NASA Astrophysics Data System (ADS)
Liu, Shande; Zhang, Junjie; Gao, Zeliang; Wei, Lei; Zhang, Shaojun; He, Jingliang; Tao, Xutang
2014-02-01
The generations of high energy 2nd- and 3rd-order stimulated Raman scattering lasers based on the α-BaTeMo2O9 crystal were demonstrated for the first time. The Raman gain coefficient has been compared with that of the YVO4 crystal. A maximum total Stokes radiation energy of 27.3 mJ was obtained, containing 20.1 mJ 2nd-order Stokes energy at 1318 nm, together with 7.2 mJ 3rd-order Stokes energy at 1497 nm, giving an overall conversion efficiency of 35.9% and a slope efficiency of 54.5%. With an optical coating design, a total 3rd- and 4th-order Stokes energy of 16.5 mJ was generated. The maximum energy for 4th-order Stokes radiation at 1731 nm was 2 mJ. The pulse durations for the 2nd-, 3rd-, and 4th-order Stokes shift were 10 ns, 8.6 ns, and 5.2 ns, respectively. Our experimental results show that the α-BTM crystal is a promising Raman crystal for the generations of eye-safe radiations.
Energy accounting of River Severn tidal power schemes
NASA Astrophysics Data System (ADS)
Roberts, F.
1982-07-01
Energy accounting comparisons are constructed in order to make an economic analysis of three different tidal generating schemes for the Severn River in Britain. The plans included ebb generation, flood generation, and turbine-sluice configurations, and the analysis comprised totaling the energy needed to complete the construction in relation to the projected output. Necessary construction components numbered caissons, shipping locks, embankments, transmission facilities, and turbines, with inputs limited to 1.75%/yr once the installations are completed. The total outputs for the installations were modeled as 12, 18, and 18 TWh/yr, respectively, with a projected lifetime of 120 yr. The least output/input ratio was found to be 10:1, with a highest possible value of 16:1. The energy return is highest with the smallest installation, a factor which is offset by the increased return with larger capacity.
Bread Basket: a gaming model for estimating home-energy costs
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
An instructional manual for answering the twenty variables on COLORADO ENERGY's computerized program estimating home energy costs. The program will generate home-energy cost estimates based on individual household data, such as total square footage, number of windows and doors, number and variety of appliances, heating system design, etc., and will print out detailed costs, showing the percentages of the total household budget that energy costs will amount to over a twenty-year span. Using the program, homeowners and policymakers alike can predict the effects of rising energy prices on total spending by Colorado households.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Underhill, Gary K.; Carlson, Ronald A.; Clendinning, William A.
1976-01-01
Econimic analysis, next to technical analysis, has traditionally constituted the major decision-making tool of the capitalist economic system. As lon as capitalism survives, this will remain to be the case. However, during the current period of increasing scarcity and cost of energy -- a period accompanied by higher than normal inflation rates -- a proposed project may appear attractive and economic when, in fact, its demands on energy resources are extraordinarily high. Such a conclusion could well be the case when the major energy expenditure in construction or operation is directed toward a fuel, the price of which is heldmore » unusually low by legal regulation. Net energetics analysis, as applied to energy generation facilities, is a method for determining the total amount of energy, IE, required to construct, operate, and maintain the energy generation facility compared to the total energy, TE, generated (or converted) throughout the facility's lifetime. Fuel consumed by the facility as direct input to the conversion or utiliztion process is not considered a debit while energy generated is not considered a credit in the calculation of the construction, operation, and maintenance energy account, IE. Energy required to run equipment auxiliary to the conversion process is, on the other hand, considered a debit to IE. The latter considerations apply to the production, processing, and transport of fuel but not to the energy content of the fuel itself.« less
Federal Register 2010, 2011, 2012, 2013, 2014
2011-11-21
... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Project No. 14246-000] KC Hydro LLC of... equipment with total hydraulic capacity of 246 cubic feet per second (cfs) and total installed generating...-file, mail an original and seven copies to: Kimberly D. Bose, Secretary, Federal Energy Regulatory...
Cloud-generated radiative heating and its generation of available potential energy
NASA Technical Reports Server (NTRS)
Stuhlmann, R.; Smith, G. L.
1989-01-01
The generation of zonal available potential energy (APE) by cloud radiative heating is discussed. The APE concept was mathematically formulated by Lorenz (1955) as a measure of the maximum amount of total potential energy that is available for conversion by adiabatic processes to kinetic energy. The rate of change of APE is the rate of the generation of APE minus the rate of conversion between potential and kinetic energy. By radiative transfer calculations, a mean cloud-generated radiative heating for a well defined set of cloud classes is derived as a function of cloud optical thickness. The formulation is suitable for using a general cloud parameter data set and has the advantage of taking into account nonlinearities between the microphysical and macrophysical cloud properties and the related radiation field.
Federal Register 2010, 2011, 2012, 2013, 2014
2012-04-27
... hydropower turbines and generators having a total combined generating capacity of 192 kilowatts; (4) an... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Project No. 14335-000] Stoughton Water..., Motions To Intervene, and Competing Applications On December 7, 2011, the Stoughton Water Power Company...
Federal Register 2010, 2011, 2012, 2013, 2014
2012-03-13
... hydropower turbines and generators having a total combined generating capacity of 192 kilowatts; (4) an... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Project No. 14335-000] Stoughton Water..., Motions To Intervene, and Competing Applications On December 7, 2011, the Stoughton Water Power Company...
Data-Driven Learning of Total and Local Energies in Elemental Boron
NASA Astrophysics Data System (ADS)
Deringer, Volker L.; Pickard, Chris J.; Csányi, Gábor
2018-04-01
The allotropes of boron continue to challenge structural elucidation and solid-state theory. Here we use machine learning combined with random structure searching (RSS) algorithms to systematically construct an interatomic potential for boron. Starting from ensembles of randomized atomic configurations, we use alternating single-point quantum-mechanical energy and force computations, Gaussian approximation potential (GAP) fitting, and GAP-driven RSS to iteratively generate a representation of the element's potential-energy surface. Beyond the total energies of the very different boron allotropes, our model readily provides atom-resolved, local energies and thus deepened insight into the frustrated β -rhombohedral boron structure. Our results open the door for the efficient and automated generation of GAPs, and other machine-learning-based interatomic potentials, and suggest their usefulness as a tool for materials discovery.
Data-Driven Learning of Total and Local Energies in Elemental Boron.
Deringer, Volker L; Pickard, Chris J; Csányi, Gábor
2018-04-13
The allotropes of boron continue to challenge structural elucidation and solid-state theory. Here we use machine learning combined with random structure searching (RSS) algorithms to systematically construct an interatomic potential for boron. Starting from ensembles of randomized atomic configurations, we use alternating single-point quantum-mechanical energy and force computations, Gaussian approximation potential (GAP) fitting, and GAP-driven RSS to iteratively generate a representation of the element's potential-energy surface. Beyond the total energies of the very different boron allotropes, our model readily provides atom-resolved, local energies and thus deepened insight into the frustrated β-rhombohedral boron structure. Our results open the door for the efficient and automated generation of GAPs, and other machine-learning-based interatomic potentials, and suggest their usefulness as a tool for materials discovery.
Dollars from Sense: The Economic Benefits of Renewable Energy
DOE R&D Accomplishments Database
1997-09-01
This document illustrates direct economic benefits, including job creation, of renewable energy technologies. Examples of electricity generation from biomass, wind power, photovoltaics, solar thermal energy, and geothermal energy are given, with emphasis on the impact of individual projects on the state and local community. Employment numbers at existing facilities are provided, including total national employment for each renewable industry where available. Renewable energy technologies offer economic advantages because they are more labor-intensive than conventional generation technologies, and they use primarily indigenous resources.
Global renewable energy-based electricity generation and smart grid system for energy security.
Islam, M A; Hasanuzzaman, M; Rahim, N A; Nahar, A; Hosenuzzaman, M
2014-01-01
Energy is an indispensable factor for the economic growth and development of a country. Energy consumption is rapidly increasing worldwide. To fulfill this energy demand, alternative energy sources and efficient utilization are being explored. Various sources of renewable energy and their efficient utilization are comprehensively reviewed and presented in this paper. Also the trend in research and development for the technological advancement of energy utilization and smart grid system for future energy security is presented. Results show that renewable energy resources are becoming more prevalent as more electricity generation becomes necessary and could provide half of the total energy demands by 2050. To satisfy the future energy demand, the smart grid system can be used as an efficient system for energy security. The smart grid also delivers significant environmental benefits by conservation and renewable generation integration.
Global Renewable Energy-Based Electricity Generation and Smart Grid System for Energy Security
Islam, M. A.; Hasanuzzaman, M.; Rahim, N. A.; Nahar, A.; Hosenuzzaman, M.
2014-01-01
Energy is an indispensable factor for the economic growth and development of a country. Energy consumption is rapidly increasing worldwide. To fulfill this energy demand, alternative energy sources and efficient utilization are being explored. Various sources of renewable energy and their efficient utilization are comprehensively reviewed and presented in this paper. Also the trend in research and development for the technological advancement of energy utilization and smart grid system for future energy security is presented. Results show that renewable energy resources are becoming more prevalent as more electricity generation becomes necessary and could provide half of the total energy demands by 2050. To satisfy the future energy demand, the smart grid system can be used as an efficient system for energy security. The smart grid also delivers significant environmental benefits by conservation and renewable generation integration. PMID:25243201
2002-01-01
Beginning with the December 2002 issue of the Energy Information Administration's Short-Term Energy Outlook (STEO), electricity generation and related fuel consumption totals will be presented on a basis that is consistent with the definitions and aggregates used in the 2001 edition of EIA's Annual Energy Review (AER). Particularly affected by these changes are the demand and balancing item totals for natural
Development and bottlenecks of renewable electricity generation in China: a critical review.
Hu, Yuanan; Cheng, Hefa
2013-04-02
This review provides an overview on the development and status of electricity generation from renewable energy sources, namely hydropower, wind power, solar power, biomass energy, and geothermal energy, and discusses the technology, policy, and finance bottlenecks limiting growth of the renewable energy industry in China. Renewable energy, dominated by hydropower, currently accounts for more than 25% of the total electricity generation capacity. China is the world's largest generator of both hydropower and wind power, and also the largest manufacturer and exporter of photovoltaic cells. Electricity production from solar and biomass energy is at the early stages of development in China, while geothermal power generation has received little attention recently. The spatial mismatch in renewable energy supply and electricity demand requires construction of long-distance transmission networks, while the intermittence of renewable energy poses significant technical problems for feeding the generated electricity into the power grid. Besides greater investment in research and technology development, effective policies and financial measures should also be developed and improved to better support the healthy and sustained growth of renewable electricity generation. Meanwhile, attention should be paid to the potential impacts on the local environment from renewable energy development, despite the wider benefits for climate change.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Miller, N.; Ye, Z.
This report documents part of a multiyear research program dedicated to the development of requirements to support the definition, design, and demonstration of a distributed generation-electric power system interconnection interface concept. The report focuses on the dynamic behavior of power systems when a significant portion of the total energy resource is distributed generation. It also focuses on the near-term reality that the majority of new DG relies on rotating synchronous generators for energy conversion.
Energy consumption renewable energy development and environmental impact in Algeria - Trend for 2030
NASA Astrophysics Data System (ADS)
Sahnoune, F.; Imessad, K.; Bouakaz, D. M.
2017-02-01
The study provides a detailed analysis of the energy production and consumption in Algeria and the associated CO2 emissions. Algeria is an important energy producer (oil and natural gas). The production is currently around 155 MToe. The total primary energy consumption amounted to about 58 MToe equivalent to 1.46 Toe/capita. The energy demand is still increasing, an average annual growth rate of more than 6% per year during the last decade. The growth rate for electricity production was almost twice that of the total energy consumption. In 2015, the installed capacity of the electricity generation plants reached 17.6 GW. Electricity consumption was 64.6 TWh and is expected to reach at least 75 TWh in 2020 and 130 TWh in 2030. The already high electricity demand will double by 2030. In the structure of final energy consumption, the transport sector ranks first (36%), natural gas consumption ranks second (28.5%), followed by electricity production (27.7%). By activity, the energy sector is the main source of CO2 emissions, about ¾ of the total and this sector has the most important potential for mitigation measures. CO2 emissions from this energy sector amounted to 112.2 MT CO2 as follows: 33% transport, 31% electricity production and 26% from natural gas combustion for residential use. The integration of renewable sources in the energy mix represents for Algeria a major challenge. In 2015, Algeria adopted an ambitious program for development of renewable energy. The target is to achieve 22 GW capacity of electricity from renewable by 2030 to reach a rate of 27 % of national electricity generation through renewable sources. By implementing this program, CO2 emissions of power generation will be reduced by more than 18% in 2030.
Comparison of two total energy systems for a diesel power generation plant. [deep space network
NASA Technical Reports Server (NTRS)
Chai, V. W.
1979-01-01
The capabilities and limitations, as well as the associated costs for two total energy systems for a diesel power generation plant are compared. Both systems utilize waste heat from engine cooling water and waste heat from exhaust gases. Pressurized water heat recovery system is simple in nature and requires no engine modifications, but operates at lower temperature ranges. On the other hand, a two-phase ebullient system operates the engine at constant temperature, provides higher temperature water or steam to the load, but is more expensive.
NASA Astrophysics Data System (ADS)
Song, Y.; Lysak, R. L.
2017-12-01
Parallel electrostatic electric fields provide a powerful mechanism to accelerate auroral particles to high energy in the auroral acceleration region (AAR), creating both quasi-static and Alfvenic discrete aurorae. The total field-aligned current can be written as J||total=J||+J||D, where the displacement current is denoted as J||D=(1/4π)(∂E||/∂t), which describes the E||-generation (Song and Lysak, 2006). The generation of the total field-aligned current is related to spatial gradients of the parallel vorticity caused by the axial torque acting on field-aligned flux tubes in M-I coupling system. It should be noticed that parallel electric fields are not produced by the field-aligned current. In fact, the E||-generation is caused by Alfvenic interaction in the M-I coupling system, and is favored by a low plasma density and the enhanced localized azimuthal magnetic flux. We suggest that the nonlinear interaction of incident and reflected Alfven wave packets in the AAR can create reactive stress concentration, and therefore can generate the parallel electrostatic electric fields together with a seed low density cavity. The generated electric fields will quickly deepen the seed low density cavity, which can effectively create even stronger electrostatic electric fields. The electrostatic electric fields nested in a low density cavity and surrounded by enhanced azimuthal magnetic flux constitute Alfvenic electromagnetic plasma structures, such as Alfvenic Double Layers (DLs). The Poynting flux carried by Alfven waves can continuously supply energy from the generator region to the auroral acceleration region, supporting and sustaining Alfvenic DLs with long-lasting electrostatic electric fields which accelerate auroral particles to high energy. The generation of parallel electric fields and the formation of auroral arcs can redistribute perpendicular mechanical and magnetic stresses in auroral flux tubes, decoupling the magnetosphere from ionosphere drag locally. This may enhance the magnetotail earthward shear flows and rapidly buildup stronger parallel electric fields in the auroral acceleration region, leading to a sudden and violent tail energy release, if there is accumulated free magnetic energy in the tail.
Energy and resource consumption
NASA Technical Reports Server (NTRS)
1973-01-01
The present and projected energy requirements for the United States are discussed. The energy consumption and demand sectors are divided into the categories: residential and commercial, transportation, and industrial and electrical generation (utilities). All sectors except electrical generation use varying amounts of fossile fuel resources for non-energy purposes. The highest percentage of non-energy use by sector is industrial with 71.3 percent. The household and commercial sector uses 28.4 percent, and transportation about 0.3 percent. Graphs are developed to project fossil fuel demands for non-energy purposes and the perdentage of the total fossil fuel used for non-energy needs.
High-energy infrared femtosecond pulses generated by dual-chirped optical parametric amplification.
Fu, Yuxi; Takahashi, Eiji J; Midorikawa, Katsumi
2015-11-01
We demonstrate high-energy infrared femtosecond pulse generation by a dual-chirped optical parametric amplification (DC-OPA) scheme [Opt. Express19, 7190 (2011)]. By employing a 100 mJ pump laser, a signal pulse energy exceeding 20 mJ at a wavelength of 1.4 μm was achieved before dispersion compensation. A total output energy of 33 mJ was recorded. Under a further energy scaling condition, the signal pulse was compressed to an almost transform-limited duration of 27 fs using a fused silica prism compressor. Since the DC-OPA scheme is efficient and energy scalable, design parameters for obtaining 100 mJ level infrared pulses are presented, which are suitable as driver lasers for the energy scaling of high-order harmonic generation with sub-keV photon energy.
A Novel Electro Conductive Graphene/Silicon-Dioxide Thermo-Electric Generator
NASA Astrophysics Data System (ADS)
Rahman, Ataur; Abdi, Yusuf
2017-03-01
Thermoelectric generators are all solid-state devices that convert heat energy into electrical energy. The total energy (fuel) supplied to the engine, approximately 30 to 40% is converted into useful mechanical work; whereas the remaining is expelled to the environment as heat through exhaust gases and cooling systems, resulting in serious green house gas (GHG) emission. By converting waste energy into electrical energy is the aim of this manuscript. The technologies reported on waste heat recovery from exhaust gas of internal combustion engines (ICE) are thermo electric generators (TEG) with finned type, Rankine cycle (RC) and Turbocharger. This paper has presented an electro-conductive graphene oxide/silicon-dioxide (GO-SiO2) composite sandwiched by phosphorus (P) and boron (B) doped silicon (Si) TEG to generate electricity from the IC engine exhaust heat. Air-cooling and liquid cooling techniques adopted conventional TEG module has been tested individually for the electricity generation from IC engine exhausts heat at engine speed of 1000-3000rpm. For the engine speed of 7000 rpm, the maximum voltage was recorded as 1.12V and 4.00V for the air-cooling and liquid cooling respectively. The GO-SiO2 simulated result shows that it’s electrical energy generation is about 80% more than conventional TEG for the exhaust temperature of 500°C. The GO-SiO2 composite TEG develops 524W to 1600W at engine speed 1000 to 5000 rpm, which could contribute to reduce the 10-12% of engine total fuel consumption and improve emission level by 20%.
Light Water Reactor Sustainability Program Integrated Program Plan
DOE Office of Scientific and Technical Information (OSTI.GOV)
McCarthy, Kathryn A.; Busby, Jeremy; Hallbert, Bruce
2014-04-01
Nuclear power has safely, reliably, and economically contributed almost 20% of electrical generation in the United States over the past two decades. It remains the single largest contributor (more than 70%) of non-greenhouse-gas-emitting electric power generation in the United States. Domestic demand for electrical energy is expected to experience a 31% growth from 2009 to 2035. At the same time, most of the currently operating nuclear power plants will begin reaching the end of their initial 20-year extension to their original 40-year operating license for a total of 60 years of operation. Figure E-1 shows projected nuclear energy contribution tomore » the domestic generating capacity. If current operating nuclear power plants do not operate beyond 60 years, the total fraction of generated electrical energy from nuclear power will begin to decline—even with the expected addition of new nuclear generating capacity. The oldest commercial plants in the United States reached their 40th anniversary in 2009. The U.S. Department of Energy Office of Nuclear Energy’s Research and Development Roadmap (Nuclear Energy Roadmap) organizes its activities around four objectives that ensure nuclear energy remains a compelling and viable energy option for the United States. The four objectives are as follows: (1) develop technologies and other solutions that can improve the reliability, sustain the safety, and extend the life of the current reactors; (2) develop improvements in the affordability of new reactors to enable nuclear energy to help meet the Administration’s energy security and climate change goals; (3) develop sustainable nuclear fuel cycles; and (4) understand and minimize the risks of nuclear proliferation and terrorism. The Light Water Reactor Sustainability (LWRS) Program is the primary programmatic activity that addresses Objective 1. This document summarizes the LWRS Program’s plans.« less
Solar updraft power generator with radial and curved vanes
NASA Astrophysics Data System (ADS)
Hafizh, Hadyan; Hamsan, Raziff; Zamri, Aidil Azlan Ahmad; Keprawi, Mohamad Fairuz Mohamad; Shirato, Hiromichi
2018-02-01
Solar radiation is the largest source of energy available on earth and the solar updraft power generator (SUPG) is a renewable energy facility capable of harnessing its abundant power. Unlike the conventional wind turbines that harness natural wind in the atmosphere and often encounter with the intermittent issue or even complete cut-off from airflow, the SUPG creates artificial wind as a result of solar-induced convective flows. However, the SUPG has an inherent low total efficiency due to the conversion of thermal energy into pressure energy. Acknowledging the low efficiency and considering its potential as a renewable energy facility, the current work aims to increase the total efficiency by installing a series of guide walls inside the collector. Two types of guide walls were used i.e. radial and curved vanes. The result with curved vanes showed that the updraft velocity is higher compare to those without vanes. About 18% and 64% improvement of updraft velocity and mechanical power were attained respectively. Furthermore, it was observed that the role of radial vanes configuration was more to produce a smooth updraft velocity profile rather than increasing the total efficiency.
Scope for energy improvement for hospital imaging services in the USA.
Esmaeili, Amin; Twomey, Janet M; Overcash, Michael R; Soltani, Seyed A; McGuire, Charles; Ali, Kamran
2015-04-01
To aid radiologists by measuring the carbon footprint of CT scans by quantifying in-hospital and out-of-hospital energy use and to assess public health impacts. The study followed a standard life cycle assessment protocol to measure energy from a CT scan then expanding to all hospital electrical energy related to CT usage. In addition, all the fuel energy used to generate electricity and to manufacture the CT consumables was measured. The study was conducted at two hospitals. The entire life cycle energy for a CT scan was 24-34 kWh of natural resource energy per scan. The actual active patient scan energy that produces the images is only about 1.6% of this total life cycle energy. This large multiplier to get total CT energy is a previously undocumented environmental response to the direct radiology order for a patient CT scan. The CT in-hospital energy related to idle periods, where the machine is on but no patients are being scanned and is 14-30-fold higher than the energy used for the CT image. The in-hospital electrical energy of a CT scan makes up only about 25% of the total energy footprint. The rest is generated outside the hospital: 54-62% for generation and transmission of the electricity, while 13-22% is for all the energy to make the consumables. Different CT scanners have some influences on the results and could help guide purchase of CT equipment. The transparent, detailed life cycle approach allows the data from this study to be used by radiologists to examine details of both direct and of unseen energy impacts of CT scans. The public health (outside-the-hospital) impact (including the patients receiving a CT) needs to be measured and included. © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Dutton, Spencer M.; Fisk, William J.
For a stand-alone retail building, a primary school, and a secondary school in each of the 16 California climate zones, the EnergyPlus building energy simulation model was used to estimate how minimum mechanical ventilation rates (VRs) affect energy use and indoor air concentrations of an indoor-generated contaminant. The modeling indicates large changes in heating energy use, but only moderate changes in total building energy use, as minimum VRs in the retail building are changed. For example, predicted state-wide heating energy consumption in the retail building decreases by more than 50% and total building energy consumption decreases by approximately 10% asmore » the minimum VR decreases from the Title 24 requirement to no mechanical ventilation. The primary and secondary schools have notably higher internal heat gains than in the retail building models, resulting in significantly reduced demand for heating. The school heating energy use was correspondingly less sensitive to changes in the minimum VR. The modeling indicates that minimum VRs influence HVAC energy and total energy use in schools by only a few percent. For both the retail building and the school buildings, minimum VRs substantially affected the predicted annual-average indoor concentrations of an indoor generated contaminant, with larger effects in schools. The shape of the curves relating contaminant concentrations with VRs illustrate the importance of avoiding particularly low VRs.« less
Energy Management: Money in the Bank.
ERIC Educational Resources Information Center
Have, Pete van der
2001-01-01
Discusses how the University of Utah developed a new chiller plant that could handle the existing and future loads of energy requirements while being totally financed via the implementation of energy saving retrofits, but not benefitting from the operations savings generated by their implementation. (GR)
NASA Technical Reports Server (NTRS)
Felder, James L.; Tong, Michael T.; Chu, Julio
2012-01-01
In a previous study by the authors it was shown that the N3-X, a 300 passenger hybrid wing body (HWB) aircraft with a turboelectric distributed propulsion (TeDP) system, was able to meet the NASA Subsonic Fixed Wing (SFW) project goal for N+3 generation aircraft of at least a 60% reduction in total energy consumption as compared to the best in class current generation aircraft. This previous study combined technology assumptions that represented the highest anticipated values that could be matured to technology readiness level (TRL) 4-6 by 2030. This paper presents the results of a sensitivity analysis of the total mission energy consumption to reductions in each key technology assumption. Of the parameters examined, the mission total energy consumption was most sensitive to changes to total pressure loss in the propulsor inlet. The baseline inlet internal pressure loss is assumed to be an optimistic 0.5%. An inlet pressure loss of 3% increases the total energy consumption 9%. However changes to reduce inlet pressure loss can result in additional distortion to the fan which can reduce fan efficiency or vice versa. It is very important that the inlet and fan be analyzed and optimized as a single unit. The turboshaft hot section is assumed to be made of ceramic matrix composite (CMC) with a 3000 F maximum material temperature. Reducing the maximum material temperature to 2700 F increases the mission energy consumption by only 1.5%. Thus achieving a 3000 F temperature in CMCs is important but not central to achieving the energy consumption objective of the N3-X/TeDP. A key parameter in the efficiency of superconducting motors and generators is the size of the superconducting filaments in the stator. The size of the superconducting filaments in the baseline model is assumed to be 10 microns. A 40 micron filament, which represents current technology, results in a 200% increase in AC losses in the motor and generator stators. This analysis shows that for a system with 40 micron filaments the higher stator losses plus the added weight and power of larger cryocoolers results in a 4% increase in mission energy consumption. If liquid hydrogen is used to cool the superconductors the 40 micron fibers results in a 200% increase in hydrogen required for cooling. Each pound of hydrogen used as fuel displaces 3 pounds of jet fuel. For the N3-X on the reference mission the additional hydrogen due to the increase stator losses reduces the total fuel weight 10%. The lighter fuel load and attendant vehicle resizing reduces the total energy consumption more than the higher stator losses increase it. As a result with hydrogen cooling there is a slight reduction in mission energy consumption with increasing stator losses. This counter intuitive result highlights the need to consider the full system impact of changes rather than just at the component or subsystem level.
The use of urban wood waste as an energy resource
NASA Astrophysics Data System (ADS)
Khudyakova, G. I.; Danilova, D. A.; Khasanov, R. R.
2017-06-01
The capabilities use of wood waste in the Ekaterinburg city, generated during the felling of trees and sanitation in the care of green plantations in the streets, parks, squares, forest parks was investigated in this study. In the cities at the moment, all the wood, that is removed from city streets turns into waste completely. Wood waste is brought to the landfill of solid household waste, and moreover sorting and evaluation of the quantitative composition of wood waste is not carried out. Several technical solutions that are used in different countries have been proposed for the energy use of wood waste: heat and electrical energy generation, liquid and solid biofuel production. An estimation of the energy potential of the city wood waste was made, for total and for produced heat and electrical energy based on modern engineering developments. According to our estimates total energy potential of wood waste in the city measure up more 340 thousand GJ per year.
Terawatt-scale photovoltaics: Trajectories and challenges
DOE Office of Scientific and Technical Information (OSTI.GOV)
Haegel, Nancy M.; Margolis, Robert; Buonassisi, Tonio
The annual potential of solar energy far exceeds the world's total energy consumption. However, the vision of photovoltaics (PVs) providing a substantial fraction of global electricity generation and total energy demand is far from being realized. What technical, infrastructure, economic, and policy barriers need to be overcome for PVs to grow to the multiple terawatt (TW) scale? Here, we assess realistic future scenarios and make suggestions for a global agenda to move toward PVs at a multi-TW scale.
Output from Linear Generator for VIV-driven Buoys
2014-09-01
demonstration of VIV-based energy harvesting was accomplished by Bernitsas of Vortex Hydro Energy and their Vortex Induced Vibration Aquatic Clean Energy...the total actuation distance of the force input device was limited to 2.75 inches, a lever arm amplified the stroke input by 4.93X to raise the...magnet plunger ±6.78 inches above and below the horizontal axis (total 13.56-inch stroke distance). The magnet plunger served to drive two 2-inch
Terawatt-scale photovoltaics: Trajectories and challenges
Haegel, Nancy M.; Margolis, Robert; Buonassisi, Tonio; ...
2017-04-13
The annual potential of solar energy far exceeds the world's total energy consumption. However, the vision of photovoltaics (PVs) providing a substantial fraction of global electricity generation and total energy demand is far from being realized. What technical, infrastructure, economic, and policy barriers need to be overcome for PVs to grow to the multiple terawatt (TW) scale? Here, we assess realistic future scenarios and make suggestions for a global agenda to move toward PVs at a multi-TW scale.
Evaluation of a total energy-rate sensor on a transport airplane
NASA Technical Reports Server (NTRS)
Ostroff, A. J.; Hueschen, R. M.; Hellbaum, R. F.; Belcastro, C. M.; Creedon, J. F.
1983-01-01
A sensor that measures the rate of change of total energy of an airplane with respect to the airstream has been evaluated. The sensor consists of two cylindrical probes located on the fuselage of a transport airplane, an in line acoustic filter, and a pressure sensing altitude rate transducer. Sections of this report include the sensor description and experimental configuration, frequency response tests, analytical model development, and flight test results for several airplane maneuvers. The results section includes time history comparisons between data generated by the total energy rate sensor and calculated data derived from independent sources.
Energy harvesting on highway bridges.
DOT National Transportation Integrated Search
2011-01-01
A concept for harvesting energy from the traffic-induced loadings on a highway bridge using piezoelectric : materials to generate electricity was explored through the prototype stage. A total of sixteen lead-zirconate : titanate (PZT) Type 5A piezoel...
Random number generators tested on quantum Monte Carlo simulations.
Hongo, Kenta; Maezono, Ryo; Miura, Kenichi
2010-08-01
We have tested and compared several (pseudo) random number generators (RNGs) applied to a practical application, ground state energy calculations of molecules using variational and diffusion Monte Carlo metheds. A new multiple recursive generator with 8th-order recursion (MRG8) and the Mersenne twister generator (MT19937) are tested and compared with the RANLUX generator with five luxury levels (RANLUX-[0-4]). Both MRG8 and MT19937 are proven to give the same total energy as that evaluated with RANLUX-4 (highest luxury level) within the statistical error bars with less computational cost to generate the sequence. We also tested the notorious implementation of linear congruential generator (LCG), RANDU, for comparison. (c) 2010 Wiley Periodicals, Inc.
Hu, Junhui; Jong, Januar; Zhao, Chunsheng
2010-01-01
To increase the vibration energy-harvesting capability of the piezoelectric generator based on a cantilever beam, we have proposed a piezoelectric generator that not only uses the strain change of piezoelectric components bonded on a cantilever beam, but also employs the weights at the tip of the cantilever beam to hit piezoelectric components located on the 2 sides of weights. A prototype of the piezoelectric generator has been fabricated and its characteristics have been measured and analyzed. The experimental results show that the piezoelectric components operating in the hit mode can substantially enhance the energy harvesting of the piezoelectric generator on a cantilever beam. Two methods are used and compared in the management of rectified output voltages from different groups of piezoelectric components. In one of them, the DC voltages from rectifiers are connected in series, and then the total DC voltage is applied to a capacitor. In another connection, the DC voltage from each group is applied to different capacitors. It is found that 22.3% of the harvested energy is wasted due to the series connection. The total output electric energy of our piezoelectric generator at nonresonance could be up to 43 nJ for one vibration excitation applied by spring, with initial vibration amplitude (0-p) of 18 mm and frequency of 18.5 Hz, when the rectified voltages from different groups of piezoelectric components are connected to their individual capacitors. In addition, the motion and impact of the weights at the tip of the cantilever beam are theoretically analyzed, which well explains the experimental phenomena and suggests the measures to improve the generator.
Nuclear's role in 21. century Pacific rim energy use
DOE Office of Scientific and Technical Information (OSTI.GOV)
Singer, Clifford; Taylor, J'Tia
2007-07-01
Extrapolations contrast the future of nuclear energy use in Japan and the Republic of Korea (ROK) to that of the Association of Southeast Asian Nations (ASEAN). Japan can expect a gradual rise in the nuclear fraction of a nearly constant total energy use rate as the use of fossil fuels declines. ROK nuclear energy rises gradually with total energy use. ASEAN's total nuclear energy use rate can rapidly approach that of the ROK if Indonesia and Vietnam make their current nuclear energy targets by 2020, but experience elsewhere suggests that nuclear energy growth may be slower than planned. Extrapolations aremore » based on econometric calibration to a utility optimization model of the impact of growth of population, gross domestic product, total energy use, and cumulative fossil carbon use. Fractions of total energy use from fluid fossil fuels, coal, water-driven electrical power production, nuclear energy, and wind and solar electric energy sources are fit to market fractions data. Where historical data is insufficient for extrapolation, plans for non-fossil energy are used as a guide. Extrapolations suggest much more U.S. nuclear energy and spent nuclear fuel generation than for the ROK and ASEAN until beyond the first half of the twenty-first century. (authors)« less
Case study of McCormick place cogeneration project
DOE Office of Scientific and Technical Information (OSTI.GOV)
Overstreet, E.L.
1994-12-31
In the authors business of providing district energy services, competition is the key to his being able to have a positive impact on the environment, business stability, and economic activity. In the district energy industry, the competitive options are for property owners to continue to self generate energy to meet their needs, purchase energy from a company that utilizes electricity during off-peak hours to produce chilled water or take advantage of a total solution of purchasing tri-generation energy from Trigen-Peoples District Energy Company. Tri-generation is an innovative technology which involves the simultaneous production of steam, chilled water, and electricity. Themore » McCormick Place cogeneration project calls for producing steam and chilled water (co-) for use by the Metropolitan Pier and Exposition Authority (MPEA). The plant will produce electricity (tri-) to run the production equipment.« less
Thermodynamic analyses of a biomass-coal co-gasification power generation system.
Yan, Linbo; Yue, Guangxi; He, Boshu
2016-04-01
A novel chemical looping power generation system is presented based on the biomass-coal co-gasification with steam. The effects of different key operation parameters including biomass mass fraction (Rb), steam to carbon mole ratio (Rsc), gasification temperature (Tg) and iron to fuel mole ratio (Rif) on the system performances like energy efficiency (ηe), total energy efficiency (ηte), exergy efficiency (ηex), total exergy efficiency (ηtex) and carbon capture rate (ηcc) are analyzed. A benchmark condition is set, under which ηte, ηtex and ηcc are found to be 39.9%, 37.6% and 96.0%, respectively. Furthermore, detailed energy Sankey diagram and exergy Grassmann diagram are drawn for the entire system operating under the benchmark condition. The energy and exergy efficiencies of the units composing the system are also predicted. Copyright © 2016 Elsevier Ltd. All rights reserved.
A 400-kWe high-efficiency steam turbine for industrial cogeneration
NASA Technical Reports Server (NTRS)
Leibowitz, H. M.
1982-01-01
An advanced state-of-the-art steam turbine-generator developed to serve as the power conversion subsystem for the Department of Energy's Sandia National Laboratories' Solar Total-Energy Project (STEP) is described. The turbine-generator, which is designed to provide 400-kW of net electrical power, represents the largest turbine-generator built specifically for commercial solar-powered cogeneration. The controls for the turbine-generator incorporate a multiple, partial-arc entry to provide efficient off-design performance, as well as an extraction control scheme to permit extraction flow regulation while maintaining 110-spsig pressure. Normal turbine operation is achieved while synchronized to a local utility and in a stand-alone mode. In both cases, the turbine-generator features automatic load control as well as remote start-up and shutdown capability. Tests totaling 200 hours were conducted to confirm the integrity of the turbine's mechanical structure and control function. Performance tests resulted in a measured inlet throttle flow of 8,450 pounds per hour, which was near design conditions.
Rooftop Solar Photovoltaic Technical Potential in the United States. A Detailed Assessment
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gagnon, Pieter; Margolis, Robert; Melius, Jennifer
2016-01-01
How much energy could be generated if PV modules were installed on all of the suitable roof area in the nation? To answer this question, we first use GIS methods to process a lidar dataset and determine the amount of roof area that is suitable for PV deployment in 128 cities nationwide, containing 23% of U.S. buildings, and provide PV-generation results for a subset of those cities. We then extend the insights from that analysis to the entire continental United States. We develop two statistical models--one for small buildings and one for medium and large buildings--and populate them with geographicmore » variables that correlate with rooftop's suitability for PV. We simulate the productivity of PV installed on the suitable roof area, and present the technical potential of PV on both small buildings and medium/large buildings for every state in the continental US. Within the 128 cities covered by lidar data, 83% of small buildings have a location suitable for a PV installation, but only 26% of the total rooftop area of small buildings is suitable for development. The sheer number of buildings in this class, however, gives small buildings the greatest technical potential. Small building rooftops could accommodate 731 GW of PV capacity and generate 926 TWh/year of PV energy, approximately 65% of rooftop PV's total technical potential. We conclude by summing the PV-generation results for all building sizes and therefore answering our original question, estimating that the total national technical potential of rooftop PV is 1,118 GW of installed capacity and 1,432 TWh of annual energy generation. This equates to 39% of total national electric-sector sales.« less
Rooftop Solar Photovoltaic Technical Potential in the United States
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gagnon, Pieter; Margolis, Robert; Melius, Jennifer
2016-01-01
How much energy could we generate if PV modules were installed on all of the suitable roof area in the nation? To answer this question, we first use GIS methods to process a lidar dataset and determine the amount of roof area that is suitable for PV deployment in 128 cities nationwide, containing 23% of U.S. buildings, and provide PV-generation results for a subset of those cities. We then extend the insights from that analysis to the entire continental United States. We develop two statistical models -- one for small buildings and one for medium and large buildings -- andmore » populate them with geographic variables that correlate with rooftop's suitability for PV. We simulate the productivity of PV installed on the suitable roof area, and present the technical potential of PV on both small buildings and medium/large buildings for every state in the continental US. Within the 128 cities covered by lidar data, 83% of small buildings have a location suitable for a PV installation, but only 26% of the total rooftop area of small buildings is suitable for development. The sheer number of buildings in this class, however, gives small buildings the greatest technical potential. Small building rooftops could accommodate 731 GW of PV capacity and generate 926 TWh/year of PV energy, approximately 65% of rooftop PV's total technical potential. We conclude by summing the PV-generation results for all building sizes and therefore answering our original question, estimating that the total national technical potential of rooftop PV is 1,118 GW of installed capacity and 1,432 TWh of annual energy generation. This equates to 39% of total national electric-sector sales.« less
Carbon-free hydrogen production from low rank coal
NASA Astrophysics Data System (ADS)
Aziz, Muhammad; Oda, Takuya; Kashiwagi, Takao
2018-02-01
Novel carbon-free integrated system of hydrogen production and storage from low rank coal is proposed and evaluated. To measure the optimum energy efficiency, two different systems employing different chemical looping technologies are modeled. The first integrated system consists of coal drying, gasification, syngas chemical looping, and hydrogenation. On the other hand, the second system combines coal drying, coal direct chemical looping, and hydrogenation. In addition, in order to cover the consumed electricity and recover the energy, combined cycle is adopted as addition module for power generation. The objective of the study is to find the best system having the highest performance in terms of total energy efficiency, including hydrogen production efficiency and power generation efficiency. To achieve a thorough energy/heat circulation throughout each module and the whole integrated system, enhanced process integration technology is employed. It basically incorporates two core basic technologies: exergy recovery and process integration. Several operating parameters including target moisture content in drying module, operating pressure in chemical looping module, are observed in terms of their influence to energy efficiency. From process modeling and calculation, two integrated systems can realize high total energy efficiency, higher than 60%. However, the system employing coal direct chemical looping represents higher energy efficiency, including hydrogen production and power generation, which is about 83%. In addition, optimum target moisture content in drying and operating pressure in chemical looping also have been defined.
Nuclear power generation and fuel cycle report 1997
DOE Office of Scientific and Technical Information (OSTI.GOV)
NONE
1997-09-01
Nuclear power is an important source of electric energy and the amount of nuclear-generated electricity continued to grow as the performance of nuclear power plants improved. In 1996, nuclear power plants supplied 23 percent of the electricity production for countries with nuclear units, and 17 percent of the total electricity generated worldwide. However, the likelihood of nuclear power assuming a much larger role or even retaining its current share of electricity generation production is uncertain. The industry faces a complex set of issues including economic competitiveness, social acceptance, and the handling of nuclear waste, all of which contribute to themore » uncertain future of nuclear power. Nevertheless, for some countries the installed nuclear generating capacity is projected to continue to grow. Insufficient indigenous energy resources and concerns over energy independence make nuclear electric generation a viable option, especially for the countries of the Far East.« less
Heat energy of various ignition sparks
NASA Technical Reports Server (NTRS)
Silsbee, F B; Loeb, L B; Fonseca, E L
1920-01-01
This report describes a method developed at the Bureau of Standards for measuring the total energy liberated as heat in a spark gap by an ignition system. Since this heat energy is obtained from the electromagnetic energy stored in the windings of the magneto or coil, it is a measure of the effectiveness of the device as an electric generator. Part 2 gives the results of measurements in absolute units of the total heat supplied to a spark gap by ignition systems of different types operating at various speeds, under conditions substantially equivalent to those in the cylinder of a high-compression aviation engine.
NASA Astrophysics Data System (ADS)
Butuzov, V. A.; Amerkhanov, R. A.; Grigorash, O. V.
2018-05-01
Solar and geothermal energy systems are shown to have received the widest use among all kinds of renewable sources of energy for heat supply purposes around the world. The power capacities and amounts of thermal energy generated by solar and geothermal heat supply systems around the world are presented by way of comparison. The thermal power capacity of solar heat supply systems installed around the world as of 2015 totaled 268.1 GW, and the thermal energy generated by them amounted to 225 TW h/year. The thermal power capacity of geothermal heat supply systems installed around the world totaled 70.3 GW, and the thermal energy generated by them amounted to 163 TW h/year. Information on the geothermal heat supply systems in the leading countries around the world based on the data reported at the World Geothermal Congress held in 2015 is presented. It is shown that China, with the installed thermal power capacities of its geothermal heat supply stations totaling 17.87 GW and the amount of thermal energy generated per annum equal to 48.435 TW h/year, is the world's leader in this respect. The structures of geothermal heat supply systems by the kinds of heat consumption used around the world are presented. The systems equipped with geothermal heat pumps accounted for 70.95% in the total installed capacity and for 55.3% in the total amount of generated heat. For systems that do not use heat pumps, those serving for pools account for the largest share amounting to 44.74% in installed capacity and to 45.43% in generated heat. A total of 2218 geothermal wells with the total length equal to 9534 km (with 38.7% of them for heat supply purposes) were drilled in 42 countries in the period from 2010 to 2014. In Russia, geothermal heat supply systems are in operation mainly in Dagestan, in Krasnodar krai, and in Kamchatka. The majority of these systems have been made without breaking the stream after the well outlet. A cyclic control arrangement is also used. The combined geothermal and solar heat supply system with an installed thermal power capacity of 5 MW that is in operation in the Rozovyi settlement, Krasnodar krai, is described. In the summer time, the solar installation with a capacity of 115 kW is used for supplying hot water to residential houses and for restoring the geothermal well pore pressure. The basic process circuit and characteristics of the geothermal heat supply system with the installed thermal power capacity of 8.7 MW operating in the Khankala settlement, the city of Groznyi, are given. The specific feature of this system is that the spent geothermal heat carrier is reinjected into a specially drilled inclined well. Advanced geothermal heat supply technologies involving reinjection of the spent geothermal heat carrier, combination with binary power units, use of heat pumps for recovering the spent heat carrier, and protection of equipment from corrosion and deposits are proposed.
Flywheel energy storage for electromechanical actuation systems
NASA Technical Reports Server (NTRS)
Hockney, Richard L.; Goldie, James H.; Kirtley, James L.
1991-01-01
The authors describe a flywheel energy storage system designed specifically to provide load-leveling for a thrust vector control (TVC) system using electromechanical actuators (EMAs). One of the major advantages of an EMA system over a hydraulic system is the significant reduction in total energy consumed during the launch profile. Realization of this energy reduction will, however, require localized energy storage capable of delivering the peak power required by the EMAs. A combined flywheel-motor/generator unit which interfaces directly to the 20-kHz power bus represents an ideal candidate for this load leveling. The overall objective is the definition of a flywheel energy storage system for this application. The authors discuss progress on four technical objectives: (1) definition of the specifications for the flywheel-motor/generator system, including system-level trade-off analysis; (2) design of the flywheel rotor; (3) design of the motor/generator; and (4) determination of the configuration for the power management system.
Flywheel energy storage for electromechanical actuation systems
NASA Astrophysics Data System (ADS)
Hockney, Richard L.; Goldie, James H.; Kirtley, James L.
The authors describe a flywheel energy storage system designed specifically to provide load-leveling for a thrust vector control (TVC) system using electromechanical actuators (EMAs). One of the major advantages of an EMA system over a hydraulic system is the significant reduction in total energy consumed during the launch profile. Realization of this energy reduction will, however, require localized energy storage capable of delivering the peak power required by the EMAs. A combined flywheel-motor/generator unit which interfaces directly to the 20-kHz power bus represents an ideal candidate for this load leveling. The overall objective is the definition of a flywheel energy storage system for this application. The authors discuss progress on four technical objectives: (1) definition of the specifications for the flywheel-motor/generator system, including system-level trade-off analysis; (2) design of the flywheel rotor; (3) design of the motor/generator; and (4) determination of the configuration for the power management system.
NASA Technical Reports Server (NTRS)
1982-01-01
The development of a commercially viable and cost-effective phospheric acid fuel cell powered on-site integrated energy system (OS/IES) is described. The fuel cell offers energy efficients in the range of 35-40% of the higher heating value of available fuels in the form of electrical energy. In addition, by utilizing the thermal energy generated for heating, ventilating and air-conditioning (HVAC), a fuel cell OS/IES could provide total energy efficiencies in the neighborhood of 80%. Also, the Engelhard fuel cell OS/IES offers the important incentive of replacing imported oil with domestically produced methanol, including coal-derived methanol.
Federal Register 2010, 2011, 2012, 2013, 2014
2011-11-22
... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Project No. 14306-000] The City of East... powerhouse; (4) a new or refurbished vertical Francis turbine/generator with total hydraulic capacity of 100...: Kimberly D. Bose, Secretary, Federal Energy Regulatory Commission, 888 First Street NE., Washington, DC...
Integration of permanent magnet synchronous generator wind turbines into power grid
NASA Astrophysics Data System (ADS)
Abedini, Asghar
The world is seeing an ever-increasing demand for electrical energy. The future growth of electrical power generation needs to be a mix of technologies including fossil fuels, hydro, nuclear, wind, and solar. The federal and state energy agencies have taken several proactive steps to increase the share of renewable energy in the total generated electrical power. In 2005, 11.1% of the total 1060 GW electricity generation capacity was from Renewable Energy Sources (RES) in the US. The power capacity portfolio included 9.2% from hydroelectric, 0.87% from wind, and 0.7% from biomass. Other renewable power capacity included 2.8 GW of geothermal, 0.4 GW of solar thermal, and 0.2 GW of solar PV. Although the share of renewable energy sources is small compared with the total power capacity, they are experiencing a high and steady growth. The US is leading the world in wind energy growth with a 27% increase in 2006 and a projected 26% increase in 2007, according to the American Wind Energy Association (AWEA). The US Department of Energy benchmarked a goal to meet 5% of the nation's energy need by launching the Wind Powering America (WPA) program. Although renewable energy sources have many benefits, their utilization in the electrical grid does not come without cost. The higher penetration of RES has introduced many technical and non-technical challenges, including power quality, reliability, safety and protection, load management, grid interconnections and control, new regulations, and grid operation economics. RES such as wind and PV are also intermittent in nature. The energy from these sources is available as long as there is wind or sunlight. However, these are energies that are abundant in the world and the power generated from these sources is pollution free. Due to high price of foundation of wind farms, employing variable speed wind turbines to maximize the extracted energy from blowing wind is more beneficial. On the other hand, since wind power is intermittent, integrating energy storage systems with wind farms has attracted a lot of attention. These two subjects are addressed in this dissertation in detail. Permanent Magnet Synchronous Generators (PMSG) are used in variable speed wind turbines. In this thesis, the dynamic of the PMSG is investigated and a power electronic converter is designed to integrate the wind turbine to the grid. The risks of PMSG wind turbines such as low voltage ride through and short circuits, are assessed and the methods of mitigating the risks are discussed. In the second section of the thesis, various methods of smoothing wind turbine output power are explained and compared. Two novel methods of output power smoothing are analyzed: Rotor inertia and Super capacitors. The advantages and disadvantages of each method are explained and the dynamic model of each method is developed. The performance of the system is evaluated by simulating the wind turbine system in each method. The concepts of the methods of smoothing wind power can be implemented in other types of wind turbines such as Doubly Fed Induction Generator (DFIG) wind turbines.
Promotion of renewable energy in some MENA region countries
NASA Astrophysics Data System (ADS)
Abdeladim, K.; Bouchakour, S.; Arab, A. Hadj; Ould Amrouche, S.; Yassaa, N.
2018-05-01
In recent years Middle East and North African (MENA) countries, are showing efforts about the integration of renewable electricity into their power markets. Indeed, installations were already achieved and renewable energy programs were launched. The Algerian program remains one of the most ambitious with its installation capacity up to 22GW of power generating to be installed by 2030. More than 60 % of the total capacity is planned to be solar photovoltaic (PV). Like Algeria, Morocco has integrated development project with a target to develop by 2020 a 2000 MW capacity of electricity production from solar energy. The Tunisian government has launched its first phase of the renewable power generation program, with an objective to install 1,000 MW of renewable power capacity over the 2017-2020 periods, where 650 MW of the total capacity is planned to be solar and 350 MW wind. One of the leading Arab country in wind energy, these recent years is Egypt, with its more than 700 megawatt of operational power generation plants and has launched significant projects development in solar energy. Regarding Jordan, the government has taken different steps in this field of energy with a Strategy plan 2007-2020, by implementing a large scale of projects on renewable energy sources, with an objective to cover 10% of the country’s energy supply, from renewable sources by the year 2020. Concerning Lebanon, the country is looking to attain an integration of 12 % by 2020.
NASA Astrophysics Data System (ADS)
Jatzeck, Bernhard Michael
2000-10-01
The application of the Luus-Jaakola direct search method to the optimization of stand-alone hybrid energy systems consisting of wind turbine generators (WTG's), photovoltaic (PV) modules, batteries, and an auxiliary generator was examined. The loads for these systems were for agricultural applications, with the optimization conducted on the basis of minimum capital, operating, and maintenance costs. Five systems were considered: two near Edmonton, Alberta, and one each near Lethbridge, Alberta, Victoria, British Columbia, and Delta, British Columbia. The optimization algorithm used hourly data for the load demand, WTG output power/area, and PV module output power. These hourly data were in two sets: seasonal (summer and winter values separated) and total (summer and winter values combined). The costs for the WTG's, PV modules, batteries, and auxiliary generator fuel were full market values. To examine the effects of price discounts or tax incentives, these values were lowered to 25% of the full costs for the energy sources and two-thirds of the full cost for agricultural fuel. Annual costs for a renewable energy system depended upon the load, location, component costs, and which data set (seasonal or total) was used. For one Edmonton load, the cost for a renewable energy system consisting of 27.01 m2 of WTG area, 14 PV modules, and 18 batteries (full price, total data set) was 6873/year. For Lethbridge, a system with 22.85 m2 of WTG area, 47 PV modules, and 5 batteries (reduced prices, seasonal data set) cost 2913/year. The performance of renewable energy systems based on the obtained results was tested in a simulation using load and weather data for selected days. Test results for one Edmonton load showed that the simulations for most of the systems examined ran for at least 17 hours per day before failing due to either an excessive load on the auxiliary generator or a battery constraint being violated. Additional testing indicated that increasing the generator capacity and reducing the maximum allowed battery charge current during the time of the day at which these failures occurred allowed the simulation to successfully operate.
Yamamoto, Takahiko; Koshiji, Kohji; Homma, Akihiko; Tatsumi, Eisuke; Taenaka, Yoshiyuki
2008-01-01
Transcutaneous energy transmission (TET) that uses electromagnetic induction between the external and internal coils of a transformer is the most promising method to supply driving energy to a totally implantable artificial heart without invasion. Induction-heating (IH) cookers generate magnetic flux, and if a cooker is operated near a transcutaneous transformer, the magnetic flux generated will link with the external and internal coils of the transcutaneous transformer. This will affect the performance of the TET and the artificial heart system. Hence, it is necessary to improve the magnetic field immunity of the TET system. During operation of the system, if the transcutaneous transformer is in close proximity to an IH cooker, the electric power generated by the cooker and coupled to the transformer can drive the artificial heart system. To prevent this coupling, the external coil was shielded with a conductive shield that had a slit in it. This reduces the coupling between the transformer and the magnetic field generated by the induction cooker. However, the temperature of the shield increased due to heating by eddy currents. The temperature of the shield can be reduced by separating the IH cooker and the shield.
Response of lightning energy and total electron content with sprites over Antarctic Peninsula
NASA Astrophysics Data System (ADS)
Suparta, W.; Yusop, N.
2017-05-01
This paper investigates the response of the lightning energy with the total electron content (TEC) derived from GPS over Antarctic Peninsula during St Patrick’s geomagnetic storm. During this event, sprite as one of the mesospheric transient luminous events (TLEs) associated with positive cloud-to-ground (+CG) lightning discharges can be generated. In this work, GPS and lightning data for the period from 14 to 20 March 2015 is analyzed. Geomagnetic activity and electric field data are also processed to relate the geomagnetic storm and lightning. Results show that during St Patrick’s geomagnetic storm, the lighting energy was produced up to ∼257 kJ. The ionospheric TEC was obtained 60 TECU, 38 TECU and 78 TECU between 18:00 and 21:00 UT for OHI3, PALV and ROTH stations, respectively. The peak of lightning energy was observed 14 hours after peaked of TEC. Sprite possibly generated through the electrical coupling process between the top cloud, middle and upper atmosphere with the DC electric field found to be ∼10 mVm-1 which leading to the sprite generation after the return strokes on 18 March 2015.
Shepertycky, Michael; Li, Qingguo
2015-01-01
Background Much research in the field of energy harvesting has sought to develop devices capable of generating electricity during daily activities with minimum user effort. No previous study has considered the metabolic cost of carrying the harvester when determining the energetic effects it has on the user. When considering device carrying costs, no energy harvester to date has demonstrated the ability to generate a substantial amount of electricity (> 5W) while maintaining a user effort at the same level or lower than conventional power generation methods (e.g. hand crank generator). Methodology/Principal Findings We developed a lower limb-driven energy harvester that is able to generate approximately 9W of electricity. To quantify the performance of the harvester, we introduced a new performance measure, total cost of harvesting (TCOH), which evaluates a harvester’s overall efficiency in generating electricity including the device carrying cost. The new harvester captured the motion from both lower limbs and operated in the generative braking mode to assist the knee flexor muscles in slowing the lower limbs. From a testing on 10 participants under different walking conditions, the harvester achieved an average TCOH of 6.1, which is comparable to the estimated TCOH for a conventional power generation method of 6.2. When generating 5.2W of electricity, the TCOH of the lower limb-driven energy harvester (4.0) is lower than that of conventional power generation methods. Conclusions/Significance These results demonstrated that the lower limb-driven energy harvester is an energetically effective option for generating electricity during daily activities. PMID:26039493
Shepertycky, Michael; Li, Qingguo
2015-01-01
Much research in the field of energy harvesting has sought to develop devices capable of generating electricity during daily activities with minimum user effort. No previous study has considered the metabolic cost of carrying the harvester when determining the energetic effects it has on the user. When considering device carrying costs, no energy harvester to date has demonstrated the ability to generate a substantial amount of electricity (> 5W) while maintaining a user effort at the same level or lower than conventional power generation methods (e.g. hand crank generator). We developed a lower limb-driven energy harvester that is able to generate approximately 9W of electricity. To quantify the performance of the harvester, we introduced a new performance measure, total cost of harvesting (TCOH), which evaluates a harvester's overall efficiency in generating electricity including the device carrying cost. The new harvester captured the motion from both lower limbs and operated in the generative braking mode to assist the knee flexor muscles in slowing the lower limbs. From a testing on 10 participants under different walking conditions, the harvester achieved an average TCOH of 6.1, which is comparable to the estimated TCOH for a conventional power generation method of 6.2. When generating 5.2W of electricity, the TCOH of the lower limb-driven energy harvester (4.0) is lower than that of conventional power generation methods. These results demonstrated that the lower limb-driven energy harvester is an energetically effective option for generating electricity during daily activities.
Relevance of Clean Coal Technology for India’s Energy Security: A Policy Perspective
NASA Astrophysics Data System (ADS)
Garg, Amit; Tiwari, Vineet; Vishwanathan, Saritha
2017-07-01
Climate change mitigation regimes are expected to impose constraints on the future use of fossil fuels in order to reduce greenhouse gas (GHG) emissions. In 2015, 41% of total final energy consumption and 64% of power generation in India came from coal. Although almost a sixth of the total coal based thermal power generation is now super critical pulverized coal technology, the average CO2 emissions from the Indian power sector are 0.82 kg-CO2/kWh, mainly driven by coal. India has large domestic coal reserves which give it adequate energy security. There is a need to find options that allow the continued use of coal while considering the need for GHG mitigation. This paper explores options of linking GHG emission mitigation and energy security from 2000 to 2050 using the AIM/Enduse model under Business-as-Usual scenario. Our simulation analysis suggests that advanced clean coal technologies options could provide promising solutions for reducing CO2 emissions by improving energy efficiencies. This paper concludes that integrating climate change security and energy security for India is possible with a large scale deployment of advanced coal combustion technologies in Indian energy systems along with other measures.
Energy transfers in internal tide generation, propagation and dissipation in the deep ocean
NASA Astrophysics Data System (ADS)
Floor, J. W.; Auclair, F.; Marsaleix, P.
The energy transfers associated with internal tide (IT) generation by a semi-diurnal surface tidal wave impinging on a supercritical meridionally uniform deep ocean ridge on the f-plane, and subsequent IT-propagation are analysed using the Boussinesq, free-surface, terrain-following ocean model Symphonie. The energy diagnostics are explicitly based on the numerical formulation of the governing equations, permitting a globally conservative, high-precision analysis of all physical and numerical/artificial energy transfers in a sub-domain with open lateral boundaries. The net primary energy balances are quantified using a moving average of length two tidal periods in a simplified control simulation using a single time-step, minimal diffusion, and a no-slip sea floor. This provides the basis for analysis of enhanced vertical and horizontal diffusion and a free-slip bottom boundary condition. After a four tidal period spin-up, the tidally averaged (net) primary energy balance in the generation region, extending ±20 km from the ridge crest, shows that the surface tidal wave loses approximately C = 720 W/m or 0.3% of the mean surface tidal energy flux (2.506 × 10 5 W/m) in traversing the ridge. This corresponds mainly to the barotropic-to-baroclinic energy conversion due to stratified flow interaction with sloping topography. Combined with a normalised net advective flux of baroclinic potential energy of 0.9 × C this causes a net local baroclinic potential energy gain of 0.72 × C and a conversion into baroclinic kinetic energy through the baroclinic buoyancy term of 1.18 × C. Tidally averaged, about 1.14 × C is radiated into the abyssal ocean through the total baroclinic flux of internal pressure associated with the IT- and background density field. This total baroclinic pressure flux is therefore not only determined by the classic linear surface-to-internal tide conversion, but also by the net advection of baroclinic (background) potential energy, indicating the importance of local processes other than linear IT-motion. In the propagation region (PR), integrated over the areas between 20 and 40 km from the ridge crest, the barotropic and baroclinic tide are decoupled. The net incoming total baroclinic pressure flux is balanced by local potential energy gain and outward baroclinic flux of potential energy associated with the total baroclinic density. The primary net energy balances are robust to changes in the vertical diffusion coefficient, whereas relatively weak horizontal diffusion significantly reduces the outward IT energy flux. Diapycnal mixing due to vertical diffusion causes an available potential energy loss of about 1% of the total domain-averaged potential energy gain, which matches {km-1}/{km}ρ0KVN2 to within 0.5%, for km linearly distributed grid-levels and constant background density ρ0, vertical diffusivity ( KV) and buoyancy frequency ( N).
Science-Driven Innovation Can Reduce Wind Energy Costs by 50% by 2030 |
-technology innovations, the unsubsidized cost of wind energy could drop to 50% of current levels, equivalent resulting innovations enabled by advances in science will impact the levelized cost of energy (defined as the total cost of installing and operating a project per kilowatt-hour of electricity generated by the
High precision measurements on fission-fragment de-excitation
NASA Astrophysics Data System (ADS)
Oberstedt, Stephan; Gatera, Angélique; Geerts, Wouter; Göök, Alf; Hambsch, Franz-Josef; Vidali, Marzio; Oberstedt, Andreas
2017-11-01
In recent years nuclear fission has gained renewed interest both from the nuclear energy community and in basic science. The first, represented by the OECD Nuclear Energy Agency, expressed the need for more accurate fission cross-section and fragment yield data for safety assessments of Generation IV reactor systems. In basic science modelling made much progress in describing the de-excitation mechanism of neutron-rich isotopes, e.g. produced in nuclear fission. Benchmarking the different models require a precise experimental data on prompt fission neutron and γ-ray emission, e.g. multiplicity, average energy per particle and total dissipated energy per fission, preferably as function of fission-fragment mass and total kinetic energy. A collaboration of scientists from JRC Geel (formerly known as JRC IRMM) and other institutes took the lead in establishing a dedicated measurement programme on prompt fission neutron and γ-ray characteristics, which has triggered even more measurement activities around the world. This contribution presents new advanced instrumentation and methodology we use to generate high-precision spectral data and will give a flavour of future data needs and opportunities.
NASA Astrophysics Data System (ADS)
Liao, Yanfen; Fang, Hailin; Zhang, Hengjin; Yu, Zhaosheng; Liu, Zhichao; Ma, Xiaoqian
2017-05-01
To meet with the demand of energy conservation and emission reduction policies, the method of life cycle assessment (LCA) was used to assess the feasibility of Hybrid Giant Napier (HGN) direct-fired power generation in this study. The entire life cycle is consisted of five stages (cultivation and harvesting, transportation, drying and comminuting, direct-fired power generation, constructing and decommissioning of biomass power plant). Analytical results revealed that to generate 10000kWh electricity, 10.925 t of customized HGN fuel (moisture content: 30 wt%) and 6659.430 MJ of energy were required. The total environmental impact potential was 0.927 PET2010 (person equivalents, targeted, in 2010) and the global warming (GW), acidification (AC), and nutrient (NE) emissions were 339.235 kg CO2-eq, 22.033 kg SO2-eq, and 25.486 kg NOx-eq respectively. The effect of AC was the most serious among all calculated category impacts. The energy requirements and environmental impacts were found to be sensitive to single yield, average transport distance, cutting frequency, and moisture content. The results indicated that HGN direct-fired power generation accorded well with Chinese energy planning; in addition, HGN proved to be a promising contribution to reducing non-renewable energy consumption and had encouraging prospects as a renewable energy plant.
Yan, Linbo; He, Boshu
2017-07-01
A clean power generation system was built based on the steam co-gasification of biomass and coal in a quadruple fluidized bed gasifier. The chemical looping with oxygen uncoupling technology was used to supply oxygen for the calciner. The solid oxide fuel cell and the steam turbine were combined to generate power. The calcium looping and mineral carbonation were used for CO 2 capture and sequestration. The aim of this work was to study the characteristics of this system. The effects of key operation parameters on the system total energy efficiency (ŋ ten ), total exergy efficiency (ŋ tex ) and carbon sequestration rate (R cs ) were detected. The energy and exergy balance calculations were implemented and the corresponding Sankey and Grassmann diagrams were drawn. It was found that the maximum energy and exergy losses occurred in the steam turbine. The system ŋ ten and ŋ tex could be ∼50% and ∼47%, and R cs could be over unit. Copyright © 2017 Elsevier Ltd. All rights reserved.
First-Principles Prediction of Densities of Amorphous Materials: The Case of Amorphous Silicon
NASA Astrophysics Data System (ADS)
Furukawa, Yoritaka; Matsushita, Yu-ichiro
2018-02-01
A novel approach to predict the atomic densities of amorphous materials is explored on the basis of Car-Parrinello molecular dynamics (CPMD) in density functional theory. Despite the determination of the atomic density of matter being crucial in understanding its physical properties, no first-principles method has ever been proposed for amorphous materials until now. We have extended the conventional method for crystalline materials in a natural manner and pointed out the importance of the canonical ensemble of the total energy in the determination of the atomic densities of amorphous materials. To take into account the canonical distribution of the total energy, we generate multiple amorphous structures with several different volumes by CPMD simulations and average the total energies at each volume. The density is then determined as the one that minimizes the averaged total energy. In this study, this approach is implemented for amorphous silicon (a-Si) to demonstrate its validity, and we have determined the density of a-Si to be 4.1% lower and its bulk modulus to be 28 GPa smaller than those of the crystal, which are in good agreement with experiments. We have also confirmed that generating samples through classical molecular dynamics simulations produces a comparable result. The findings suggest that the presented method is applicable to other amorphous systems, including those for which experimental knowledge is lacking.
Investigating the water consumption for electricity generation at Turkish power plants
NASA Astrophysics Data System (ADS)
El-Khozondar, Balkess; Aydinalp Koksal, Merih
2017-11-01
The water-energy intertwined relationship has recently gained more importance due to the high water consumption in the energy sector and to the limited availability of the water resources. The energy and electricity demand of Turkey is increasing rapidly in the last two decades. More thermal power plants are expected to be built in the near future to supply the rapidly increasing demand in Turkey which will put pressure on water availability. In this study, the water consumption for electricity generation at Turkish power plants is investigated. The main objectives of this study are to identify the amount of water consumed to generate 1 kWh of electricity for each generation technology currently used in Turkey and to investigate ways to reduce the water consumption at power plants expected to be built in the near future to supply the increasing demand. The various electricity generation technology mixture scenarios are analyzed to determine the future total and per generation water consumption, and water savings based on changes of cooling systems used for each technology. The Long-range Energy Alternatives Planning (LEAP) program is used to determine the minimum water consuming electricity generation technology mixtures using optimization approaches between 2017 and 2035.
Gamma-ray Output Spectra from 239 Pu Fission
Ullmann, John
2015-05-25
The gamma-ray multiplicities, individual gamma-ray energy spectra, and total gamma energy spectra following neutron-induced fission of 239Pu were measured using the DANCE detector at Los Alamos. Corrections for detector response were made using a forward-modeling technique based on propagating sets of gamma rays generated from a paramaterized model through a GEANT model of the DANCE array and adjusting the parameters for best fit to the measured spectra. The results for the gamma-ray spectrum and multiplicity are in general agreement with previous results, but the measured total gamma-ray energy is about 10% higher. We found that a dependence of the gamma-raymore » spectrum on the gamma-ray multplicity was also observed. Finally, global model calculations of the multiplicity and gamma energy distributions are in good agreement with the data, but predict a slightly softer total-energy distribution.« less
Code of Federal Regulations, 2013 CFR
2013-07-01
... energy output of the combustion turbine in MW. (2) For combined-cycle and combined heat and power... the heat recovery steam generator, and 100 percent of the total useful thermal energy output that is... Where: Ps = useful thermal energy of the steam, measured relative to ISO conditions, not used to...
Code of Federal Regulations, 2012 CFR
2012-07-01
... energy output of the combustion turbine in MW. (2) For combined-cycle and combined heat and power... the heat recovery steam generator, and 100 percent of the total useful thermal energy output that is... Where: Ps = useful thermal energy of the steam, measured relative to ISO conditions, not used to...
Code of Federal Regulations, 2011 CFR
2011-07-01
... energy output of the combustion turbine in MW. (2) For combined-cycle and combined heat and power... the heat recovery steam generator, and 100 percent of the total useful thermal energy output that is... Where: Ps = useful thermal energy of the steam, measured relative to ISO conditions, not used to...
Code of Federal Regulations, 2014 CFR
2014-07-01
... energy output of the combustion turbine in MW. (2) For combined-cycle and combined heat and power... the heat recovery steam generator, and 100 percent of the total useful thermal energy output that is... Where: Ps = useful thermal energy of the steam, measured relative to ISO conditions, not used to...
NASA Astrophysics Data System (ADS)
Carley, Sanya
In response to mounting concerns about climate change and an over-dependence on fossil fuels, U.S. state governments have assumed leadership roles in energy policy. State leaders across the country have constructed policies that target electricity sector operations, and aim to increase the percentage of renewable electricity generation, increase the use of distributed generation, and decrease carbon footprints. The policy literature, however, lacks compelling empirical evidence that state initiatives toward these ends are effective. This research seeks to contribute empirical insights that can help fill this void in the literature, and advance policy knowledge about the efficacy of these instruments. This three-essay dissertation focuses on the assessment of state energy policy instruments aimed at the diversification, decentralization, and decarbonization of the U.S. electricity sector. The first essay considers the effects of state efforts to diversify electricity portfolios via increases in renewable energy. This essay asks: are state-level renewable portfolio standards (RPS) effective at increasing renewable energy deployment, as well as the share of renewable energy out of the total generation mix? Empirical results demonstrate that RPS policies so far are effectively encouraging total renewable energy deployment, but not the percentage of renewable energy generation. The second essay considers state policy efforts to decentralize the U.S. electricity sector via instruments that remove barriers to distributed generation (DG) deployment. The primary question this essay addresses is whether the removal of legal barriers acts as a primary motivating factor for DG deployment. Empirical results reveal that net metering policies are positively associated with DG deployment; interconnection standards significantly increase the likelihood that end-users will adopt DG capacity; and utility DG adoption is related to standard market forces. The third essay asks: what are the potential effects of state energy policy portfolios on carbon emissions within the U.S. electricity sector? The results from an electricity modeling scenario analysis reveal that state policy portfolios have modest to minimal carbon mitigation effects in the long run if surrounding states do not adopt similar portfolios as well. The effectiveness of state-level policy portfolios can increase significantly if surrounding states adopt similar portfolios, or with the introduction of a national carbon price.
Air pollution may alter efforts to mitigate climate change
NASA Astrophysics Data System (ADS)
Yassaa, Noureddine
2016-02-01
Renewable energy, considered in the past as a mitigation option to climate change by reducing carbon emission, is now becoming a source of energy security and competing fossil fuels in many areas of the world. According to recent reports (e.g., IEA, IRENA, REN21), renewable energy has reached in 2014 a historical record of power generation capacity. With 1712 GW installed capacity in 2014, renewable energy represents 27.7% of the world's power generating capacity. Solar photovoltaic (PV) energy, conversion of solar light to electricity through solar panels, has increased to reach 177 GW mostly due to the political engagement for the deployment of renewable through targeted programs and the decrease of PV panels prize in the market (roughly 80% decrease since 2008 according to IRENA's report). Concentrated Solar Power (CSP), reaching a total capacity of 4.4 GW in 2014 (REN21 Report), is also demonstrating a clear growth and progresses have been made with regards to the efficiency, the storage capacity and the cost. In order to reduce the energy consumption and carbon emissions, water solar heaters are being installed in the rooftop of households and a total capacity of 406 GW thermal was recorded in 2014 (REN21 Report).
Increasing the percentage of renewable energy in the Southwestern United States
USDA-ARS?s Scientific Manuscript database
Combining the output of wind farms with that of Concentrating Solar Power (CSP) plants (including a heat storage system) resulted in a substantial percentage (40%) of the total utility electrical generation in the Southwestern United States being met by renewable energy. Using wind and solar resourc...
PM, carbon, and PAH emissions from a diesel generator fuelled with soy-biodiesel blends.
Tsai, Jen-Hsiung; Chen, Shui-Jen; Huang, Kuo-Lin; Lin, Yuan-Chung; Lee, Wen-Jhy; Lin, Chih-Chung; Lin, Wen-Yinn
2010-07-15
Biodiesels have received increasing attention as alternative fuels for diesel engines and generators. This study investigates the emissions of particulate matter (PM), total carbon (TC), e.g., organic/elemental carbons, and polycyclic aromatic hydrocarbons (PAHs) from a diesel generator fuelled with soy-biodiesel blends. Among the tested diesel blends (B0, B10 (10 vol% soy-biodiesel), B20, and B50), B20 exhibited the lowest PM emission concentration despite the loads (except the 5 kW case), whereas B10 displayed lower PM emission factors when operating at 0 and 10 kW than the other fuel blends. The emission concentrations or factors of EC, OC, and TC were the lowest when B10 or B20 was used regardless of the loading. Under all tested loads, the average concentrations of total-PAHs emitted from the generator using the B10 and B20 were lower (by 38% and 28%, respectively) than those using pure petroleum diesel fuel (B0), while the emission factors of total-PAHs decreased with an increasing ratio of biodiesel to premium diesel. With an increasing loading, although the brake specific fuel consumption decreased, the energy efficiency increased despite the bio/petroleum diesel ratio. Therefore, soy-biodiesel is promising for use as an alternative fuel for diesel generators to increase energy efficiency and reduce the PM, carbon, and PAH emissions. 2010 Elsevier B.V. All rights reserved.
Intelligent and robust optimization frameworks for smart grids
NASA Astrophysics Data System (ADS)
Dhansri, Naren Reddy
A smart grid implies a cyberspace real-time distributed power control system to optimally deliver electricity based on varying consumer characteristics. Although smart grids solve many of the contemporary problems, they give rise to new control and optimization problems with the growing role of renewable energy sources such as wind or solar energy. Under highly dynamic nature of distributed power generation and the varying consumer demand and cost requirements, the total power output of the grid should be controlled such that the load demand is met by giving a higher priority to renewable energy sources. Hence, the power generated from renewable energy sources should be optimized while minimizing the generation from non renewable energy sources. This research develops a demand-based automatic generation control and optimization framework for real-time smart grid operations by integrating conventional and renewable energy sources under varying consumer demand and cost requirements. Focusing on the renewable energy sources, the intelligent and robust control frameworks optimize the power generation by tracking the consumer demand in a closed-loop control framework, yielding superior economic and ecological benefits and circumvent nonlinear model complexities and handles uncertainties for superior real-time operations. The proposed intelligent system framework optimizes the smart grid power generation for maximum economical and ecological benefits under an uncertain renewable wind energy source. The numerical results demonstrate that the proposed framework is a viable approach to integrate various energy sources for real-time smart grid implementations. The robust optimization framework results demonstrate the effectiveness of the robust controllers under bounded power plant model uncertainties and exogenous wind input excitation while maximizing economical and ecological performance objectives. Therefore, the proposed framework offers a new worst-case deterministic optimization algorithm for smart grid automatic generation control.
NASA Astrophysics Data System (ADS)
Peck, Jaron Joshua
Water is used in power generation for cooling processes in thermoelectric power. plants and currently withdraws more water than any other sector in the U.S. Reducing water. use from power generation will help to alleviate water stress in at risk areas, where droughts. have the potential to strain water resources. The amount of water used for power varies. depending on many climatic aspects as well as plant operation factors. This work presents. a model that quantifies the water use for power generation for two regions representing. different generation fuel portfolios, California and Utah. The analysis of the California Independent System Operator introduces the methods. of water energy modeling by creating an overall water use factor in volume of water per. unit of energy produced based on the fuel generation mix of the area. The idea of water. monitoring based on energy used by a building or region is explored based on live fuel mix. data. This is for the purposes of increasing public awareness of the water associated with. personal energy use and helping to promote greater energy efficiency. The Utah case study explores the effects more renewable, and less water-intensive, forms of energy will have on the overall water use from power generation for the state. Using a similar model to that of the California case study, total water savings are quantified. based on power reduction scenarios involving increased use of renewable energy. The. plausibility of implementing more renewable energy into Utah’s power grid is also. discussed. Data resolution, as well as dispatch methods, economics, and solar variability, introduces some uncertainty into the analysis.
Energy Storage Opportunities and Capabilities in a Type 3 Wind Turbine Generator: Preprint
DOE Office of Scientific and Technical Information (OSTI.GOV)
Muljadi, Eduard; Gevorgian, Vahan; Hoke, Andy
Wind power plants and other renewable power plants with power electronic interfaces are capable of delivering frequency response (both governor and/or inertial response) to the grid by a control action; thus, the reduction of available online inertia as conventional power plants are retired can be compensated by designing renewable power plant controls to include frequency response. The source of energy to be delivered as inertial response is determined by the type of generation and control strategy chosen. The cost of energy storage is expected to drop over time, and global research activities on energy storage are very active, funded bothmore » by the private industry and governments. Different industry sectors (e.g., transportation, energy) are the major drivers of the recent storage research and development. This work investigates the opportunities and capabilities of deploying energy storage in renewable power plants. In particular, we focus on wind power plants with doubly-fed induction generators, or Type 3 wind turbine generator (WTGs). We find that the total output power of a system with Type 3 WTGs with energy storage can deliver a power boost during inertial response that is up to 45% higher than one without energy storage without affecting the torque limit, thus enabling an effective delivery of ancillary services to the grid.« less
Energy performance and savings potentials with skylights
DOE Office of Scientific and Technical Information (OSTI.GOV)
Arasteh, D.; Johnson, R.; Selkowitz, S.
1984-12-01
This study systematically explores the energy effects of skylight systems in a prototypical office building module and examines the savings from daylighting. For specific climates, roof/skylight characteristics are identified that minimize total energy or peak electrical demand. Simplified techniques for energy performance calculation are also presented based on a multiple regression analysis of our data base so that one may easily evaluate daylighting's effects on total and component energy loads and electrical peaks. This provides additional insights into the influence of skylight parameters on energy consumption and electrical peaks. We use the DOE-2.1B energy analysis program with newly incorporated daylightingmore » algorithms to determine hourly, monthly, and annual impacts of daylighting strategies on electrical lighting consumption, cooling, heating, fan power, peak electrical demands, and total energy use. A data base of more than 2000 parametric simulations for 14 US climates has been generated. Parameters varied include skylight-to-roof ratio, shading coefficient, visible transmittance, skylight well light loss, electric lighting power density, roof heat transfer coefficient, and electric lighting control type. 14 references, 13 figures, 4 tables.« less
Role of nuclear energy to a future society of shortage of energy resources and global warming
NASA Astrophysics Data System (ADS)
Saito, Shinzo
2010-03-01
Human society entered into the society of large energy consumption since the industrial revolution and consumes more than 10 billion tons of oil equivalent energy a year in the world in the present time, in which over 80% is provided by fossil fuels such as coal, oil and natural gas. Total energy consumption is foreseen to increase year by year from now on due to significant economical and population growth in the developing countries such as China and India. However, fossil fuel resources are limited with conventional crude oil estimated to last about 40 years, and it is said that the peak oil production time has come now. On the other hand, global warming due to green house gases (GHG) emissions, especially carbon dioxide, has become a serious issue. Nuclear energy plays an important role as means to resolve energy security and global warming issues. Four hundred twenty-nine nuclear power plants are operating world widely producing 16% of the total electric power with total plant capacity of 386 GWe without emission of CO 2 as of 2006. It is estimated that another 250 GWe nuclear power is needed to keep the same level contribution of electricity generation in 2030. On the other hand, the Japan Atomic Energy Research Institute (JAERI) developed the very high temperature gas-cooled reactor (HTGR) named high temperature gas-cooled engineering test reactor (HTTR) and carbon free hydrogen production process (IS process). Nuclear energy utilization will surely widen in, not only electricity generation, but also various industries such as steel making, chemical industries, together with hydrogen production for transportation by introduction of HTGRs. The details of development of the HTTR and IS process are also described.
High-energy, tunable, mid-infrared, picosecond optical parametric generation in CdSiP2
NASA Astrophysics Data System (ADS)
Chaitanya Kumar, S.; Jelínek, M.; Baudisch, M.; Zawilski, K. T.; Schunemann, P. G.; Kubecek, V.; Biegert, J.; Ebrahim-Zadeh, M.
2012-06-01
We report a tunable, high-energy, single-pass, optical parametric generator (OPG) based on the new nonlinear material, cadmium silicon phosphide, CdSiP2. The OPG is pumped by a laboratory designed cavity-dumped passively mode-locked, diode-pumped, Nd:YAG oscillator, providing 25 μJ pulses in 20 ps at 5 Hz. The pump energy is further boosted by a flashlamp-pumped Nd:YAG amplifier to 2.5 mJ. The OPG is temperature tunable over 1263-1286 nm (23 nm) in the signal and 6153-6731 nm (578 nm) in the idler, corresponding to a total tuning range of 601 nm. Using the single-pass OPG configuration, we have generated signal energy as high as 636 μJ at 1283 nm, together with an idler energy of 33 μJ at 6234 nm, for 2.1 mJ of input pump energy. The signal pulses generated from the OPG have a Gaussian pulse duration of 24 ps and an FWHM spectral bandwidth of 10.4 nm at central wavelength of 1276 nm. The corresponding idler spectrum has an FWHM bandwidth of 140 nm centered at 6404 nm.
NASA Astrophysics Data System (ADS)
Elefsiniotis, A.; Becker, Th.; Schmid, U.
2014-06-01
Wireless, energy-autonomous structural health-monitoring systems in aircraft have the potential of reducing total maintenance costs. Thermoelectric energy harvesting, which seems the best choice for creating truly autonomous health monitoring sensors, is the principle behind converting waste heat to useful electrical energy through the use of thermoelectric generators. To enhance the temperature difference across the two sides of a thermoelectric generator, i.e. increasing heat flux and energy production, a phase change material acting as thermal mass is attached on one side of the thermoelectric generators while the other side is placed on the aircraft structure. The application area under investigation for this paper is the pylon aft fairing, located near the engine of an aircraft, with temperatures reaching on the inside up to 350 °C. Given these harsh operational conditions, the performance of a device, containing erythritol as a phase change material, is evaluated. The harvested energy reaching values up to 81.4 J can be regulated by a power management module capable of storing the excess energy and recovering it from the medium powering a sensor node and a wireless transceiver.
Optimal Design of Wind-PV-Diesel-Battery System using Genetic Algorithm
NASA Astrophysics Data System (ADS)
Suryoatmojo, Heri; Hiyama, Takashi; Elbaset, Adel A.; Ashari, Mochamad
Application of diesel generators to supply the load demand on isolated islands in Indonesia has widely spread. With increases in oil price and the concerns about global warming, the integration of diesel generators with renewable energy systems have become an attractive energy sources for supplying the load demand. This paper performs an optimal design of integrated system involving Wind-PV-Diesel-Battery system for isolated island with CO2 emission evaluation by using genetic algorithm. The proposed system has been designed for the hybrid power generation in East Nusa Tenggara, Indonesia-latitude 09.30S, longitude 122.0E. From simulation results, the proposed system is able to minimize the total annual cost of the system under study and reduce CO2 emission generated by diesel generators.
Energy assessment of second generation (2G) ethanol production from wheat straw in Indian scenario.
Mishra, Archana; Kumar, Akash; Ghosh, Sanjoy
2018-03-01
Impact of second-generation ethanol (2G) use in transportation sector mainly depends upon energy efficiency of entire production process. The objective of present study was to determine energy efficiency of a potential lignocellulosic feedstock; wheat straw and its conversion into cellulosic ethanol in Indian scenario. Energy efficiency was determined by calculating Net energy ratio (NER), i.e. ratio of output energy obtained by ethanol and input energy used in ethanol production. Energy consumption and generation at each step is calculated briefly (11,837.35 MJ/ha during Indian dwarf irrigated variety of wheat crop production and 7.1148 MJ/kg straw during ethanol production stage). Total energy consumption is calculated as 8.2988 MJ/kg straw whereas energy generation from ethanol is 15.082 MJ/kg straw; resulting into NER > 1. Major portion of agricultural energy input is contributed by diesel and fertilisers whereas refining process of wheat straw feedstock to ethanol and by-products require mainly in the form of steam and electricity. On an average, 1671.8 kg water free ethanol, 930 kg lignin rich biomass (for combustion), and 561 kg C5-molasses (for fodder) per hectare are produced. Findings of this study, net energy ratio (1.81) and figure of merit (14.8028 MJ/nil kg carbon) proves wheat straw as highest energy efficient lignocellulosic feedstock for the country.
Solar energy: Technology and applications
NASA Technical Reports Server (NTRS)
Williams, J. R.
1974-01-01
It is pointed out that in 1970 the total energy consumed in the U.S. was equal to the energy of sunlight received by only 0.15% of the land area of the continental U.S. The utilization of solar energy might, therefore, provide an approach for solving the energy crisis produced by the consumption of irreplaceable fossil fuels at a steadily increasing rate. Questions regarding the availability of solar energy are discussed along with the design of solar energy collectors and various approaches for heating houses and buildings by utilizing solar radiation. Other subjects considered are related to the heating of water partly or entirely with solar energy, the design of air conditioning systems based on the use of solar energy, electric power generation by a solar thermal and a photovoltaic approach, solar total energy systems, industrial and agricultural applications of solar energy, solar stills, the utilization of ocean thermal power, power systems based on the use of wind, and solar-energy power systems making use of geosynchronous power plants.
NASA Astrophysics Data System (ADS)
Almansour, Faris Abdullah
The advantages of Renewable Energy Sources (RES) are much more than the disadvantages, RES such as solar, wind energy, biomass, and geothermal, which can be used for generating distributed power but cannot directly replace the existing electric energy grid technologies. The latter are far too well established to abandon, while the new RES technologies are not sufficiently developed to meet the total energy demand. Therefore, it is sensible to gradually infuse RES into existing grids and transform the system over time Saudi Arabia (SA) is a semi-developed nation with a population of over twenty nine million people. It is the largest country in western Asia with an area of 2.225MKm2. SA's largest export is oil, owning 1/5 of the world's supply, and producing twelve million barrels a day. However, SA is far behind in developing a smart grid and RES. A lot of this is to do with lack of participation by both the government and the private business sector. Currently SA spends over $13B a year on generating electricity from oil. SA is the largest consumer of petroleum in the Middle East, due to the high demand for transportation and electricity generation. According to the Saudi electrical company, the total amount of generated power in 2011 was 190.280GW. In addition, SA's electricity consumption is currently growing 8% a year. SA aims to generate 55GW of renewable energy by 2020, in order to free up fossil fuels for export. 41GW of the 55GW will be generated from solar energy. Smart grid technologies are also under consideration in SA; this will allow an efficient and reliable way to control the energy in the future. In addition, the potential for wind and geothermal energy is very high. In this thesis, there is a full exploration of RES components which are critical to manage carbon emission and the limitations of the current grid to the new RES technologies, which face barriers to full-scale deployment. A study in Dhahran, SA has been simulated on a installing a Dual-Tariff PV system using HOMER. The result of the simulation has been discussed, analyzed, and plotted. We also give evidence in the thesis how useful the small PV systems can be as oppose to the larger scale system that must deal with location issues.
Minimization of power consumption during charging of superconducting accelerating cavities
NASA Astrophysics Data System (ADS)
Bhattacharyya, Anirban Krishna; Ziemann, Volker; Ruber, Roger; Goryashko, Vitaliy
2015-11-01
The radio frequency cavities, used to accelerate charged particle beams, need to be charged to their nominal voltage after which the beam can be injected into them. The standard procedure for such cavity filling is to use a step charging profile. However, during initial stages of such a filling process a substantial amount of the total energy is wasted in reflection for superconducting cavities because of their extremely narrow bandwidth. The paper presents a novel strategy to charge cavities, which reduces total energy reflection. We use variational calculus to obtain analytical expression for the optimal charging profile. Energies, reflected and required, and generator peak power are also compared between the charging schemes and practical aspects (saturation, efficiency and gain characteristics) of power sources (tetrodes, IOTs and solid state power amplifiers) are also considered and analysed. The paper presents a methodology to successfully identify the optimal charging scheme for different power sources to minimize total energy requirement.
Energy recovery from thermal treatment of dewatered sludge in wastewater treatment plants.
Yang, Qingfeng; Dussan, Karla; Monaghan, Rory F D; Zhan, Xinmin
Sewage sludge is a by-product generated from municipal wastewater treatment (WWT) processes. This study examines the conversion of sludge via energy recovery from gasification/combustion for thermal treatment of dewatered sludge. The present analysis is based on a chemical equilibrium model of thermal conversion of previously dewatered sludge with moisture content of 60-80%. Prior to combustion/gasification, sludge is dried to a moisture content of 25-55% by two processes: (1) heat recovered from syngas/flue gas cooling and (2) heat recovered from syngas combustion. The electricity recovered from the combined heat and power process can be reused in syngas cleaning and in the WWT plant. Gas temperature, total heat and electricity recoverable are evaluated using the model. Results show that generation of electricity from dewatered sludge with low moisture content (≤ 70%) is feasible within a self-sufficient sludge treatment process. Optimal conditions for gasification correspond to an equivalence ratio of 2.3 and dried sludge moisture content of 25%. Net electricity generated from syngas combustion can account for 0.071 kWh/m(3) of wastewater treated, which is up to 25.4-28.4% of the WWT plant's total energy consumption.
Analyzing Carbohydrate-Based Regenerative Fuel Cells as a Power Source for Unmanned Aerial Vehicles
2008-03-01
conventional means of generating electrical energy, such as turbines and internal combustion engines, in that the conventional methods normally have an...have 24 hours of daylight, this means that it must be able to store enough exergy (the total amount of energy that can theoretically be converted to...useful work, differentiated from useful energy by the efficiency of converting energy to work) to function during the time when exergy consumption is
Examination of Terrestrial Nuclear Energy’s Relevance to U.S. National Security
2011-03-24
Atomic Scientists (ECAS), an organization which he co-founded, Professor Einstein made an appeal to raise money to fund a ―great educational task‖2 to...100 gigawatts of total generating capacity.11 As of 2009, these commercial reactors met 20% of U.S. electrical 3 energy demand.12 In 2008 this...allows imported energy, but only if the imported energy does not create vulnerability, such as economic, political, or military vulnerability.40
On-Shore Central Hydraulic Power Generation for Wind and Tidal Energy
NASA Technical Reports Server (NTRS)
Jones, Jack A.; Bruce, Allan; Lim, Steven; Murray, Luke; Armstrong, Richard; Kimbrall, Richard; Cook-Chenault, Kimberly; DeGennaro, Sean
2012-01-01
Tidal energy, offshore wind energy, and onshore wind energy can be converted to electricity at a central ground location by means of converting their respective energies into high-pressure hydraulic flows that are transmitted to a system of generators by high-pressure pipelines. The high-pressure flows are then efficiently converted to electricity by a central power plant, and the low-pressure outlet flow is returned. The Department of Energy (DOE) is presently supporting a project led by Sunlight Photonics to demonstrate a 15 kW tidal hydraulic power generation system in the laboratory and possibly later submerged in the ocean. All gears and submerged electronics are completely eliminated. A second portion of this DOE project involves sizing and costing a 15 MW tidal energy system for a commercial tidal energy plant. For this task, Atlantis Resources Corporation s 18-m diameter demonstrated tidal blades are rated to operate in a nominal 2.6 m/sec tidal flow to produce approximately one MW per set of tidal blades. Fifteen units would be submerged in a deep tidal area, such as in Maine s Western Passage. All would be connected to a high-pressure (20 MPa, 2900 psi) line that is 35 cm ID. The high-pressure HEPG fluid flow is transported 500-m to on-shore hydraulic generators. HEPG is an environmentally-friendly, biodegradable, watermiscible fluid. Hydraulic adaptations to ORPC s cross-flow turbines are also discussed. For 15 MW of wind energy that is onshore or offshore, a gearless, high efficiency, radial piston pump can replace each set of top-mounted gear-generators. The fluid is then pumped to a central, easily serviceable generator location. Total hydraulic/electrical efficiency is 0.81 at full rated wind or tidal velocities and increases to 0.86 at 1/3 rated velocities.
On-Shore Central Hydraulic Power Generation for Wind and Tidal Energy
NASA Technical Reports Server (NTRS)
Jones, Jack A.; Bruce, Allan; Lim, Steven; Murray, Luke; Armstrong, Richard; Kimball, Richard; Cook-Chenault, Kimberly; DeGennaro, Sean
2012-01-01
Tidal energy, offshore wind energy, and onshore wind energy can be converted to electricity at a central ground location by means of converting their respective energies into high-pressure hydraulic flows that are transmitted to a system of generators by high-pressure pipelines. The high-pressure flows are then efficiently converted to electricity by a central power plant, and the low-pressure outlet flow is returned. The Department of Energy (DOE) is presently supporting a project led by Sunlight Photonics to demonstrate a 15 kilowatt tidal hydraulic power generation system in the laboratory and possibly later submerged in the ocean. All gears and submerged electronics are completely eliminated.A second portion of this DOE project involves sizing and costing a 15 megawatt tidal energy system for a commercial tidal energy plant. For this task, Atlantis Resources Corporation's 18-m diameter demonstrated tidal blades are rated to operate in a nominal 2.6 m/sec tidal flow to produce approximately one megawatt per set of tidal blades. Fifteen units would be submerged in a deep tidal area, such as in Maine's Western Passage. All would be connected to a high-pressure (20 megapascals, 2900 pounds per square inch) line that is 35 cm ID. The high-pressure HEPG fluid flow is transported 500-m to on-shore hydraulic generators. HEPG is an environmentally-friendly, biodegradable, water-miscible fluid. Hydraulic adaptations to ORPC's cross-flow turbines are also discussed.For 15 megawatt of wind energy that is onshore or offshore, a gearless, high efficiency, radial piston pump can replace each set of top-mounted gear-generators. The fluid is then pumped to a central, easily serviceable generator location. Total hydraulic/electrical efficiency is 0.81 at full rated wind or tidal velocities and increases to 0.86 at 1/3 rated velocities.
Energy management and cooperation in microgrids
NASA Astrophysics Data System (ADS)
Rahbar, Katayoun
Microgrids are key components of future smart power grids, which integrate distributed renewable energy generators to efficiently serve the load demand locally. However, random and intermittent characteristics of renewable energy generations may hinder the reliable operation of microgrids. This thesis is thus devoted to investigating new strategies for microgrids to optimally manage their energy consumption, energy storage system (ESS) and cooperation in real time to achieve the reliable and cost-effective operation. This thesis starts with a single microgrid system. The optimal energy scheduling and ESS management policy is derived to minimize the energy cost of the microgrid resulting from drawing conventional energy from the main grid under both the off-line and online setups, where the renewable energy generation/load demand are assumed to be non-causally known and causally known at the microgrid, respectively. The proposed online algorithm is designed based on the optimal off-line solution and works under arbitrary (even unknown) realizations of future renewable energy generation/load demand. Therefore, it is more practically applicable as compared to solutions based on conventional techniques such as dynamic programming and stochastic programming that require the prior knowledge of renewable energy generation and load demand realizations/distributions. Next, for a group of microgrids that cooperate in energy management, we study efficient methods for sharing energy among them for both fully and partially cooperative scenarios, where microgrids are of common interests and self-interested, respectively. For the fully cooperative energy management, the off-line optimization problem is first formulated and optimally solved, where a distributed algorithm is proposed to minimize the total (sum) energy cost of microgrids. Inspired by the results obtained from the off-line optimization, efficient online algorithms are proposed for the real-time energy management, which are of low complexity and work given arbitrary realizations of renewable energy generation/load demand. On the other hand, for self-interested microgrids, the partially cooperative energy management is formulated and a distributed algorithm is proposed to optimize the energy cooperation such that energy costs of individual microgrids reduce simultaneously over the case without energy cooperation while limited information is shared among the microgrids and the central controller.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mohanpurkar, Manish; Luo, Yusheng; Hovsapian, Rob
Hydropower plant (HPP) generation comprises a considerable portion of bulk electricity generation and is delivered with a low-carbon footprint. In fact, HPP electricity generation provides the largest share from renewable energy resources, which include wind and solar. Increasing penetration levels of wind and solar lead to a lower inertia on the electric grid, which poses stability challenges. In recent years, breakthroughs in energy storage technologies have demonstrated the economic and technical feasibility of extensive deployments of renewable energy resources on electric grids. If integrated with scalable, multi-time-step energy storage so that the total output can be controlled, multiple run-of-the-river (ROR)more » HPPs can be deployed. Although the size of a single energy storage system is much smaller than that of a typical reservoir, the ratings of storages and multiple ROR HPPs approximately equal the rating of a large, conventional HPP. This paper proposes cohesively managing multiple sets of energy storage systems distributed in different locations. This paper also describes the challenges associated with ROR HPP system architecture and operation.« less
Design and aero-acoustic analysis of a counter-rotating wind turbine
NASA Astrophysics Data System (ADS)
Agrawal, Vineesh V.
Wind turbines have become an integral part of the energy business because they are one of the most economical and reliable sources of renewable energy. Conventional wind turbines are capable of capturing less than half of the energy present in the wind. Hence, to make the wind turbines more efficient, it is important to increase their performance. A horizontal axis wind turbine with multiple rotors is one concept that can achieve a higher power conversion rate. Also, a concern for wind energy is the noise generated by wind turbines. Hence, an investigation into the acoustic behavior of a multi-rotor horizontal axis wind turbine is required. In response to the need of a wind turbine design with higher power coefficient, a unique design of a counter-rotating horizontal axis wind turbine (CR-HAWT) is proposed. The Blade Element Momentum (BEM) theory is used to aerodynamically design the blades of the two rotors. Modifications are made to the BEM theory to accommodate the interaction of the two rotors. The tower effect on the noise generation of the downwind rotor is investigated. Predictions are made for the total noise generated by the wind turbine at its design operating conditions. A total power coefficient of 65.2% is predicted for the proposed CR-HAWT design. A low tip speed ratio is chosen to minimize the noise generation. The aeroacoustic analysis of the CR-HAWT shows that the noise generated at its design operating conditions is within an acceptable range. Thus, the CR-HAWT is predicted to be a quiet wind turbine with a high power coefficient, making it highly desirable for small wind turbine applications.
Red meat production in australia: life cycle assessment and comparison with overseas studies.
Peters, Gregory M; Rowley, Hazel V; Wiedemann, Stephen; Tucker, Robyn; Short, Michael D; Schulz, Matthias
2010-02-15
Greenhouse gas emissions from beef production are a significant part of Australia's total contribution to climate change. For the first time an environmental life cycle assessment (LCA) hybridizing detailed on-site process modeling and input-output analysis is used to describe Australian red meat production. In this paper we report the carbon footprint and total energy consumption of three supply chains in three different regions in Australia over two years. The greenhouse gas (GHG) emissions and energy use data are compared to those from international studies on red meat production, and the Australian results are either average or below average. The increasing proportion of lot-fed beef in Australia is favorable, since this production system generates lower total GHG emissions than grass-fed production; the additional effort in producing and transporting feeds is effectively offset by the increased efficiency of meat production in feedlots. In addition to these two common LCA indicators, in this paper we also quantify solid waste generation and a soil erosion indicator on a common basis.
Climate change impacts on thermoelectric-power generation in the United States
NASA Astrophysics Data System (ADS)
Liu, L.
2015-12-01
Thermoelectric-power generation accounts for more than 70% of the total electricity generation in the United States, which requires large amounts of water for cooling purposes. Water withdrawals for thermoelectric-power generation accounted for 45% of total water use in the United States in 2010. Across the country, water demand from power plants is increasing due to pressures from growing populations and other needs, and is straining existing water resources. Moreover, temperature exceedance in receiving waters has increasingly caused power plants shut downs across parts of the country. Thermoelectric power is vulnerable to climate change owing to the combined effects of lower summer river flows and higher receiving water temperatures. In addition, the efficiency of production is reduced as air temperature rises, which propagates to more unfulfilled power demand during peak seasons. Therefore, a holistic modeling framework of water-energy-climate for the contiguous U.S. is presented here to quantify thermal output from power plants and estimate water use and energy production fluctuations due to ambient climate as well as environmental regulations. The model is calibrated on a plant-by-plant basis for year 2010 and 2011 using the available power plant inventory from the Energy Information Administration (EIA). Simulations were carried out for years 2012 and 2013, and results show moderate improvements in capturing thermal output variabilities after calibration. Future power plant operations under scenarios featuring different climate and regulatory settings were investigated. Results demonstrate the interplay among water, energy and climate, and that future changes in climate and socioeconomics significantly affect power plant operations, which may provide insights to climate change mitigation considerations and energy decisions.
On sound generation by turbulent convection: A new look at old results
NASA Technical Reports Server (NTRS)
Musielak, Z. E.; Rosner, R.; Stein, R. F.; Ulmschneider, P.
1994-01-01
We have revisited the problem of acoustic wave generation by turbulent convection in stellar atmospheres. The theory of aerodynamically generated sound, originally developed by Lighthill and later modified by Stein to include the effects of stratification, has been used to estimate the acoustic wave energy flux generated in solar and stellar convection zones. We correct the earlier computations by incorporating an improved description of the spatial and temporal spectrum of the turbulent convection. We show the dependence of the resulting wave fluxes on the nature of the turbulence, and compute the wave energy spectra and wave energy fluxes generated in the Sun on the basis of a mixing-length model of the solar convection zone. In contrast to the previous results, we show that the acoustic energy generation does not depend very sensitively on the turbulent energy spectrum. However, typical total acoustic fluxes of order F(sub A) = 5 x 10(exp 7) ergs/sq cm/s with a peak of the acoustic frequency spectrum near omega = 100 mHz are found to be comparable to those previously calculated. The acoustic flux turns out to be strongly dependent on the solar model, scaling with the mixing-length parameter alpha as alpha(exp 3.8). The computed fluxes most likely constitute a lower limit on the acoustic energy produced in the solar convection zone if recent convection simulations suggesting the presence of shocks near the upper layers of the convection zone apply to the Sun.
No time machine construction in open 2+1 gravity with timelike total energy-momentum
NASA Astrophysics Data System (ADS)
Tiglio, Manuel H.
1998-09-01
It is shown that in (2+1)-dimensional gravity an open spacetime with timelike sources and total energy momentum cannot have a stable compactly generated Cauchy horizon. This constitutes a proof of a version of Kabat's conjecture and shows, in particular, that not only a Gott time machine cannot be formed from processes such as the decay of a single cosmic string as has been shown by Carroll et al., but that, in a precise sense, a time machine cannot be constructed at all.
Energy coupling between the solar wind and the magnetosphere
NASA Technical Reports Server (NTRS)
Akasofu, S.-I.
1981-01-01
A description is given of the path leading to the first approximation expression for the solar wind-magnetosphere energy coupling function (epsilon), which correlates well with the total energy consumption rate (U sub T) of the magnetosphere. It is shown that epsilon is the primary factor controlling the time development of magnetospheric substorms and storms. The finding of this particular expression epsilon indicates how the solar wind couples its energy to the magnetosphere; the solar wind and the magnetosphere make up a dynamo. In fact, the power generated by the dynamo can be identified as epsilon through the use of a dimensional analysis. In addition, the finding of epsilon suggests that the magnetosphere is closer to a directly driven system than to an unloading system which stores the generated energy before converting it to substorm and storm energies. The finding of epsilon and its implications is considered to have significantly advanced and improved the understanding of magnetospheric processes.
Pfenniger, Alois; Obrist, Dominik; Stahel, Andreas; Koch, Volker M; Vogel, Rolf
2013-07-01
As the complexity of active medical implants increases, the task of embedding a life-long power supply at the time of implantation becomes more challenging. A periodic renewal of the energy source is often required. Human energy harvesting is, therefore, seen as a possible remedy. In this paper, we present a novel idea to harvest energy from the pressure-driven deformation of an artery by the principle of magneto-hydrodynamics. The generator relies on a highly electrically conductive fluid accelerated perpendicularly to a magnetic field by means of an efficient lever arm mechanism. An artery with 10 mm inner diameter is chosen as a potential implantation site and its ability to drive the generator is established. Three analytical models are proposed to investigate the relevant design parameters and to determine the existence of an optimal configuration. The predicted output power reaches 65 μW according to the first two models and 135 μW according to the third model. It is found that the generator, designed as a circular structure encompassing the artery, should not exceed a total volume of 3 cm³.
Analysis of renewable energy projects' implementation in Russia
NASA Astrophysics Data System (ADS)
Ratner, S. V.; Nizhegorodtsev, R. M.
2017-06-01
With the enactment in 2013 of a renewable energy scheme by contracting qualified power generation facilities working on renewable energy sources (RES), the process of construction and connection of such facilities to the Federal Grid Company has intensified in Russia. In 2013-2015, 93 projects of solar, wind, and small hydropower energy were selected on the basis of competitive bidding in the country with the purpose of subsequent support. Despite some technical and organizational problems and a time delay of some RES projects, in 2014-2015 five solar generating facilities with total capacity of 50 MW were commissioned, including 30 MW in Orenburg oblast. However, the proportion of successful projects is low and amounts to approximately 30% of the total number of announced projects. The purpose of this paper is to analyze the experience of implementation of renewable energy projects that passed through a competitive selection and gained the right to get a partial compensation for the construction and commissioning costs of RES generating facilities in the electric power wholesale market zone. The informational background for the study is corporate reports of project promoters, analytical and information materials of the Association NP Market Council, and legal documents for the development of renewable energy. The methodological base of the study is a theory of learning curves that assumes that cost savings in the production of high-tech products depends on the production growth rate (economy of scale) and gaining manufacturing experience (learning by doing). The study has identified factors that have a positive and a negative impact on the implementation of RES projects. Improvement of promotion measures in the renewable energy development in Russia corresponding to the current socio-economic situation is proposed.
NASA Astrophysics Data System (ADS)
Liu, Ruo-Yu; Taylor, Andrew; Wang, Xiang-Yu; Aharonian, Felix
2017-01-01
By interacting with the cosmic background photons during their propagation through intergalactic space, ultrahigh energy cosmic rays (UHECRs) produce energetic electron/positron pairs and photons which will initiate electromagnetic cascades, contributing to the isotropic gamma-ray background (IGRB). The generated gamma-ray flux level highly depends on the redshift evolution of the UHECR sources. Recently, the Fermi-LAT collaboration reported that 86-14+16 of the total extragalactic gamma-ray flux comes from extragalactic point sources including those unresolved ones. This leaves a limited room for the diffusive gamma ray generated via UHECR propagation, and subsequently constrains their source distribution in the Universe. Normalizing the total cosmic ray energy budget with the observed UHECR flux in the energy band of (1-4)×1018 eV, we calculate the diffuse gamma-ray flux generated through UHECR propagation. We find that in order to not overshoot the new IGRB limit, these sub-ankle UHECRs should be produced mainly by nearby sources, with a possible non-negligible contribution from our Galaxy. The distance for the majority of UHECR sources can be further constrained if a given fraction of the observed IGRB at 820 GeV originates from UHECR. We note that our result should be conservative since there may be various other contributions to the IGRB that is not included here.
NASA Astrophysics Data System (ADS)
Karki, Rajesh
Renewable energy application in electric power systems is growing rapidly worldwide due to enhanced public concerns for adverse environmental impacts and escalation in energy costs associated with the use of conventional energy sources. Photovoltaics and wind energy sources are being increasingly recognized as cost effective generation sources. A comprehensive evaluation of reliability and cost is required to analyze the actual benefits of utilizing these energy sources. The reliability aspects of utilizing renewable energy sources have largely been ignored in the past due the relatively insignificant contribution of these sources in major power systems, and consequently due to the lack of appropriate techniques. Renewable energy sources have the potential to play a significant role in the electrical energy requirements of small isolated power systems which are primarily supplied by costly diesel fuel. A relatively high renewable energy penetration can significantly reduce the system fuel costs but can also have considerable impact on the system reliability. Small isolated systems routinely plan their generating facilities using deterministic adequacy methods that cannot incorporate the highly erratic behavior of renewable energy sources. The utilization of a single probabilistic risk index has not been generally accepted in small isolated system evaluation despite its utilization in most large power utilities. Deterministic and probabilistic techniques are combined in this thesis using a system well-being approach to provide useful adequacy indices for small isolated systems that include renewable energy. This thesis presents an evaluation model for small isolated systems containing renewable energy sources by integrating simulation models that generate appropriate atmospheric data, evaluate chronological renewable power outputs and combine total available energy and load to provide useful system indices. A software tool SIPSREL+ has been developed which generates risk, well-being and energy based indices to provide realistic cost/reliability measures of utilizing renewable energy. The concepts presented and the examples illustrated in this thesis will help system planners to decide on appropriate installation sites, the types and mix of different energy generating sources, the optimum operating policies, and the optimum generation expansion plans required to meet increasing load demands in small isolated power systems containing photovoltaic and wind energy sources.
Distributed Optimal Dispatch of Distributed Energy Resources Over Lossy Communication Networks
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wu, Junfeng; Yang, Tao; Wu, Di
In this paper, we consider the economic dispatch problem (EDP), where a cost function that is assumed to be strictly convex is assigned to each of distributed energy resources (DERs), over packet dropping networks. The goal of a standard EDP is to minimize the total generation cost while meeting total demand and satisfying individual generator output limit. We propose a distributed algorithm for solving the EDP over networks. The proposed algorithm is resilient against packet drops over communication links. Under the assumption that the underlying communication network is strongly connected with a positive probability and the packet drops are independentmore » and identically distributed (i.i.d.), we show that the proposed algorithm is able to solve the EDP. Numerical simulation results are used to validate and illustrate the main results of the paper.« less
Byproduct mineral commodities used for the production of photovoltaic cells
Bleiwas, Donald I.
2010-01-01
Rising fossil fuel costs, environmental concerns relating to global climate change, and Government policy to signifcantly increase our Nation's energy independence have placed greater emphasis on the generation of electricity from renewable sources, such as the Sun (light and heat), water, and wind, which for all intents and purposes are inexhaustible resources. Although the total amount of electricity generated from the direct conversion of sunlight through photovoltaic cells is relatively small compared with that from other forms of renewable energy, the rate of growth in the sector is signifcant. The total value of energy of photovoltaic cells produced worldwide increased to nearly 7 gigawatts (GW) in 2008 from 45 megawatts (MW) in 1990, a compound annual growth rate of about 30 percent. In the United States, manufacturing of photovoltaic cells has grown exponentially to about 480 MW in 2008, accounting for 6 percent of world production, from less than 10 MW of photovoltaic capacity in 1990 (Benner, 2007; U.S. Department of Energy, Energy Information Administration, 2010), a compound annual growth rate of approxi-mately 23 percent. A production capacity of 1 GW of electricity [or 8,760 gigawatthours1 (GWh)] is equivalent to the annual electricity requirements for roughly 800,000 average households in the United States (U.S. Department of Energy, Energy Information Administration, 2010). This estimate does not include losses of electricity, such as during transmission through power lines.
The welfare effects of integrating renewable energy into electricity markets
NASA Astrophysics Data System (ADS)
Lamadrid, Alberto J.
The challenges of deploying more renewable energy sources on an electric grid are caused largely by their inherent variability. In this context, energy storage can help make the electric delivery system more reliable by mitigating this variability. This thesis analyzes a series of models for procuring electricity and ancillary services for both individuals and social planners with high penetrations of stochastic wind energy. The results obtained for an individual decision maker using stochastic optimization are ambiguous, with closed form solutions dependent on technological parameters, and no consideration of the system reliability. The social planner models correctly reflect the effect of system reliability, and in the case of a Stochastic, Security Constrained Optimal Power Flow (S-SC-OPF or SuperOPF), determine reserve capacity endogenously so that system reliability is maintained. A single-period SuperOPF shows that including ramping costs in the objective function leads to more wind spilling and increased capacity requirements for reliability. However, this model does not reflect the inter temporal tradeoffs of using Energy Storage Systems (ESS) to improve reliability and mitigate wind variability. The results with the multiperiod SuperOPF determine the optimum use of storage for a typical day, and compare the effects of collocating ESS at wind sites with the same amount of storage (deferrable demand) located at demand centers. The collocated ESS has slightly lower operating costs and spills less wind generation compared to deferrable demand, but the total amount of conventional generating capacity needed for system adequacy is higher. In terms of the total system costs, that include the capital cost of conventional generating capacity, the costs with deferrable demand is substantially lower because the daily demand profile is flattened and less conventional generation capacity is then needed for reliability purposes. The analysis also demonstrates that the optimum daily pattern of dispatch and reserves is seriously distorted if the stochastic characteristics of wind generation are ignored.
NASA Astrophysics Data System (ADS)
Kholmetskii, Alexander; Missevitch, Oleg; Yarman, Tolga
2016-02-01
We address to the Poynting theorem for the bound (velocity-dependent) electromagnetic field, and demonstrate that the standard expressions for the electromagnetic energy flux and related field momentum, in general, come into the contradiction with the relativistic transformation of four-vector of total energy-momentum. We show that this inconsistency stems from the incorrect application of Poynting theorem to a system of discrete point-like charges, when the terms of self-interaction in the product {\\varvec{j}} \\cdot {\\varvec{E}} (where the current density {\\varvec{j}} and bound electric field {\\varvec{E}} are generated by the same source charge) are exogenously omitted. Implementing a transformation of the Poynting theorem to the form, where the terms of self-interaction are eliminated via Maxwell equations and vector calculus in a mathematically rigorous way (Kholmetskii et al., Phys Scr 83:055406, 2011), we obtained a novel expression for field momentum, which is fully compatible with the Lorentz transformation for total energy-momentum. The results obtained are discussed along with the novel expression for the electromagnetic energy-momentum tensor.
Johnson, Jeremiah; Chertow, Marian
2009-04-01
Pacala and Socolow developed a framework to stabilize global greenhouse gas levels for the next fifty years using wedges of constant size representing an increasing use of existing technologies and approaches for energy efficiency, carbon free generation, renewables, and carbon storage. The research presented here applies their approach to Hawaii Island, with modifications to support local scale analysis and employing a "bottom-up" methodology that allows for wedges of various sizes. A discretely bounded spatial unit offers a testing ground for a holistic approach to improving the energy sector with the identification of local options and limitations to the implementation of a comprehensive energy strategy. Nearly 80% of total primary energy demand across all sectors for Hawaii Island is currently met using petroleum-based fuels.The Sustainable Energy Plan scenario included here presents an internally consistent set of recommendations bounded by local constraints in areas such as transportation efficiency, centralized renewable generation (e.g., geothermal, wind), reduction in transmission losses, and improved building efficiency. This scenario shows thatthe demand for primary energy in 2030 could be reduced by 23% through efficiency measures while 46% could be met by renewable generation, resulting in only 31% of the projected demand being met by fossil fuels. In 2030, the annual releases of greenhouse gases would be 3.2 Mt CO2-eq/year under the Baseline scenario, while the Sustainable Energy Plan would reduce this to 1.2 Mt CO2-eq/year--an annual emissions rate 40% below 2006 levels and 10% below 1990 levels. The total for greenhouse gas emissions during the 24-year study period (2007 to 2030) is 59.9 Mt CO2-eq under the Baseline scenario and 32.5 Mt CO2-eq under the Sustainable Energy Plan scenario. Numerous combinations of efficiency and renewable energy options can be employed in a manner that stabilizes the greenhouse gas emissions of Hawaii Island.
Solar Energy Technologies Office FY 2017 Budget At-A-Glance
DOE Office of Scientific and Technical Information (OSTI.GOV)
None, None
2016-03-01
The Solar Energy Technologies Office supports the SunShot Initiative goal to make solar energy technologies cost competitive with conventional energy sources by 2020. Reducing the total installed cost for utility-scale solar electricity by approximately 75% (2010 baseline) to roughly $0.06 per kWh without subsidies will enable rapid, large-scale adoption of solar electricity across the United States. This investment will help re-establish American technological and market leadership in solar energy, reduce environmental impacts of electricity generation, and strengthen U.S. economic competitiveness.
Energy spectrum of cascade showers induced by cosmic ray muons in the range from 50 GeV to 5 TeV
NASA Technical Reports Server (NTRS)
Ashitkov, V. D.; Kirina, T. M.; Klimakov, A. P.; Kokoulin, R. P.; Petrukhin, A. A.; Yumatov, V. I.
1985-01-01
The energy spectrum of cascade showers induced by electromagnetic interactions of high energy muons of horizontal cosmic ray flux in iron absorber was measured. The total observation time exceeded 22,000 hours. Both the energy spectrum and angular distributions of cascade showers are fairly described in terms of the usual muon generation processes, with a single power index of the parent meson spectrum over the muon energy range from 150 GeV to 5 TeV.
Biomass energy: Sustainable solution for greenhouse gas emission
NASA Astrophysics Data System (ADS)
Sadrul Islam, A. K. M.; Ahiduzzaman, M.
2012-06-01
Biomass is part of the carbon cycle. Carbon dioxide is produced after combustion of biomass. Over a relatively short timescale, carbon dioxide is renewed from atmosphere during next generation of new growth of green vegetation. Contribution of renewable energy including hydropower, solar, biomass and biofuel in total primary energy consumption in world is about 19%. Traditional biomass alone contributes about 13% of total primary energy consumption in the world. The number of traditional biomass energy users expected to rise from 2.5 billion in 2004 to 2.6 billion in 2015 and to 2.7 billion in 2030 for cooking in developing countries. Residential biomass demand in developing countries is projected to rise from 771 Mtoe in 2004 to 818 Mtoe in 2030. The main sources of biomass are wood residues, bagasse, rice husk, agro-residues, animal manure, municipal and industrial waste etc. Dedicated energy crops such as short-rotation coppice, grasses, sugar crops, starch crops and oil crops are gaining importance and market share as source of biomass energy. Global trade in biomass feedstocks and processed bioenergy carriers are growing rapidly. There are some drawbacks of biomass energy utilization compared to fossil fuels viz: heterogeneous and uneven composition, lower calorific value and quality deterioration due to uncontrolled biodegradation. Loose biomass also is not viable for transportation. Pelletization, briquetting, liquefaction and gasification of biomass energy are some options to solve these problems. Wood fuel production is very much steady and little bit increase in trend, however, the forest land is decreasing, means the deforestation is progressive. There is a big challenge for sustainability of biomass resource and environment. Biomass energy can be used to reduce greenhouse emissions. Woody biomass such as briquette and pellet from un-organized biomass waste and residues could be used for alternative to wood fuel, as a result, forest will be saved and sustainable carbon sink will be developed. Clean energy production from biomass (such as ethanol, biodiesel, producer gas, bio-methane) could be viable option to reduce fossil fuel consumption. Electricity generation from biomass is increasing throughout the world. Co-firing of biomass with coal and biomass combustion in power plant and CHP would be a viable option for clean energy development. Biomass can produce less emission in the range of 14% to 90% compared to emission from fossil for electricity generation. Therefore, biomass could play a vital role for generation of clean energy by reducing fossil energy to reduce greenhouse gas emissions. The main barriers to expansion of power generation from biomass are cost, low conversion efficiency and availability of feedstock. Internationalization of external cost in power generation and effective policies to improve energy security and carbon dioxide reduction is important to boost up the bio-power. In the long run, bio-power will depend on technological development and on competition for feedstock with food production and arable land use.
Technology Performance Report: Duke Energy Notrees Wind Storage Demonstration Project
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wehner, Jeff; Mohler, David; Gibson, Stuart
2015-11-01
Duke Energy Renewables owns and operates the Notrees Wind Farm in west Texas’s Ector and Winkler counties. The wind farm, which was commissioned in April 2009, has a total capacity of 152.6 MW generated by 55 Vestas V82 turbines, one Vestas 1-V90 experimental turbine, and 40 GE 1.5-MW turbines. The Vestas V82 turbines have a generating capacity of 1.65 MW each, the Vestas V90 turbine has a generating capacity of 1.86 MW, and the GE turbines have a generating capacity of 1.5 MW each. The objective of the Notrees Wind Storage Demonstration Project is to validate that energy storage increasesmore » the value and practical application of intermittent wind generation and is commercially viable at utility scale. The project incorporates both new and existing technologies and techniques to evaluate the performance and potential of wind energy storage. In addition, it could serve as a model for others to adopt and replicate. Wind power resources are expected to play a significant part in reducing greenhouse gas emissions from electric power generation by 2030. However, the large variability and intermittent nature of wind presents a barrier to integrating it within electric markets, particularly when competing against conventional generation that is more reliable. In addition, wind power production often peaks at night or other times when demand and electricity prices are lowest. Energy storage systems can overcome those barriers and enable wind to become a valuable asset and equal competitor to conventional fossil fuel generation.« less
Renewable energy and rural development activities experience in Bangladesh
DOE Office of Scientific and Technical Information (OSTI.GOV)
Barua, D.C.
1997-12-01
The per capita per year fuel consumption in Bangladesh is only 56 kg oil equivalent. The supply of electricity by Bangladesh power development board (BPDB) and Dhaka electricity supply authority (DESA) is mainly confined to cities and towns. Rural Electrification Board (REB) distributes electricity to the rural people through cooperatives. The rural cooperatives cover only 10% of the total population. Only about 15% of the total population is directly connected to the electricity. In order to meet the increasing energy demand for development of agriculture and industry and for the generation of better employment opportunities, it will be necessary tomore » harness all the available alternative sources of energy immediately.« less
Nayal, Figen Sisman; Mammadov, Aydin; Ciliz, Nilgun
2016-12-15
While Turkey is one of the world's largest producers and exporters of agricultural goods, it is also, at the same time a net importer of energy carriers. This dichotomy offers a strong incentive to generate energy from agricultural and farming waste; something which could provide energy security for rural areas. Combined with the enhanced energy security for farming areas, the production of energy in this manner could conceivably contribute to the overall national effort to reduce the Turkey's carbon footprint. This study explores the environmental benefits and burdens of one such option, that is, biogas production from a mixture of agricultural and animal waste through anaerobic digestion (AD), and its subsequent use for electricity and heat generation. A life-cycle assessment methodology was used, to measure the potential environmental impact of this option, in terms of global warming and total weighed impact, and to contrast it with the impact of producing the same amount of energy via an integrated gasification combined cycle process and a hard coal power plant. This study concentrates on an AD and cogeneration pilot plant, built in the Kocaeli province of Turkey and attempts to evaluate its potential environmental impacts. The study uses laboratory-scale studies, as well as literature and LCI databases to derive the operational parameters, yield and emissions of the plant. The potential impacts were calculated with EDIP 2003 methodology, using GaBi 5 LCA software. The results indicate that N 2 O emissions, resulting from the application of liquid and solid portions of digestate (a by-product of AD), as an organic fertilizer, are by far the largest contributors to global warming among all the life cycle stages. They constitute 68% of the total, whereas ammonia losses from the same process are the leading cause of terrestrial eutrophication. The photochemical ozone formation potential is significantly higher for the cogeneration phase, compared to other life cycle stages of the proposed scenario, due to NO x being emitted from the gas engine during combustion. Overall, the total environmental impact of the option was determined to be ten times lower than that of a hard coal option and 50% lower than the gasification option, since the latter does not generate digestate that is able to replace mineral fertilizer, thus mitigating the environmental footprint. Finally, the sustainability of energy production from agricultural and farm waste, via AD, was further enhanced by eliminating it from conventional waste management system practiced in the region, i.e. landfilling. Copyright © 2016 Elsevier Ltd. All rights reserved.
CO2 Reduction Effect of the Utilization of Waste Heat and Solar Heat in City Gas System
NASA Astrophysics Data System (ADS)
Okamura, Tomohito; Matsuhashi, Ryuji; Yoshida, Yoshikuni; Hasegawa, Hideo; Ishitani, Hisashi
We evaluate total energy consumption and CO2 emissions in the phase of the city gas utilization system from obtaining raw materials to consuming the product. First, we develop a simulation model which calculates CO2 emissions for monthly and hourly demands of electricity, heats for air conditioning and hot-water in a typical hospital. Under the given standard capacity and operating time of CGS, energy consumption in the equipments is calculated in detail considering the partial load efficiency and the control by the temperature of exhaust heat. Then, we explored the optimal size and operation of city gas system that minimizes the life cycle CO2 emissions or total cost. The cost-effectiveness is compared between conventional co-generation, solar heat system, and hybrid co-generation utilizing solar heat. We formulate a problem of mixed integer programming that includes integral parameters that express the state of system devices such as on/off of switches. As a result of optimization, the hybrid co-generation can reduce annual CO2 emissions by forty-three percent compared with the system without co-generation. Sensitivity for the scale of CGS on CO2 reduction and cost is also analyzed.
Regulatory Approaches for Adding Capacity to Existing Hydropower Facilities
DOE Office of Scientific and Technical Information (OSTI.GOV)
Levine, Aaron L.; Curtis, Taylor L.; Kazerooni, Borna
In 2015, hydroelectric generation accounted for more than 6 percent of total net electricity generation in the United States and 46 percent of electricity generation from all renewables. The United States has considerable hydroelectric potential beyond what is already being developed. Nearly 7 GW of this potential is found by adding capacity to existing hydropower facilities. To optimize the value of hydroelectric generation, the U.S. Department of Energy's Hydropower Vision Study highlights the importance of adding capacity to existing facilities. This report provides strategic approaches and considerations for Federal Energy Regulatory Commission licensed and exempt hydropower facilities seeking to increasemore » generation capacity, which may include increases from efficiency upgrades. The regulatory approaches reviewed for this report include capacity and non-capacity amendments, adding capacity during relicensing, and adding capacity when converting a license to a 10-MW exemption.« less
High-efficency stable 213-nm generation for LASIK application
NASA Astrophysics Data System (ADS)
Wang, Zhenglin; Alameh, Kamal; Zheng, Rong
2005-01-01
213nm Solid-state laser technology provides an alternative method to replace toxic excimer laser in LASIK system. In this paper, we report a compact fifth harmonic generation system to generate high pulse energy 213nm laser from Q-switched Nd:YAG laser for LASIK application based on three stages harmonic generation procedures. A novel crystal housing was specifically designed to hold the three crystals with each crystal has independent, precise angular adjustment structure and automatic tuning control. The crystal temperature is well maintained at ~130°C to improve harmonic generation stability and crystal operation lifetime. An output pulse energy 35mJ is obtained at 213nm, corresponding to total conversion efficiency ~10% from 1064nm pump laser. In system verification tests, the 213nm output power drops less than 5% after 5 millions pulse shots and no significant damage appears in the crystals.
Biomass boiler conversion potential in the eastern United States
Charles D. Ray; Li Ma; Thomas Wilson; Daniel Wilson; Lew McCreery; Janice K. Wiedenbeck
2013-01-01
The U.S. is the world's leading consumer of primary energy. A large fraction of this energy is used in boiler installations to generate steam and hot water for heating applications. It is estimated there are total 163,000 industrial and commercial boilers in use in the United States of all sizes. This paper characterizes the commercial and industrial boilers in...
Progress in solar thermal distributed receiver technology
NASA Astrophysics Data System (ADS)
Leonard, J. A.; Otts, J. V.
A brief discussion is given on the fundamentals of parabolic dish collectors. Private and Department of Energy supported projects which employ parabolic dish collector systems are described. These projects include: the Distribution Receiver Test Facility, Shenandoah Solar Total Energy Project, Vangurd I, Solar Plant No. 1, the Dish/Stirling Solar Electric Generating System, the Organic Rankine Cycle, and the Solarized Automotive Gas Turbine.
The Andromeda galaxy in gamma-rays
NASA Technical Reports Server (NTRS)
Oezel, M. E.; Berkhuijsen, E. M.
1987-01-01
Implications of high-energy gamma-ray observations of the Andromeda galaxy with the next generation of satellites Gamma-1 and GRO are discussed in the context of the origin of cosmic rays and gamma-ray processes. The present estimate of the total gamma-ray flux of this galaxy at energies above 100 MeV is a factor of about three less than previous estimates.
Superheat recovery system shakes savings out of A/C systems
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
1985-09-01
One of the most productive and least expensive methods of recovering waste heat is a system that reclaims the excess energy or superheat generated by closed-loop-air conditioning or refrigeration cycles. Installed recently in 72 Steak N' Shakes restaurants as part of a total energy conservation package, it has helped cut gas bills by more than 70%.
Effects of tissue impedance on heat generation during RF delivery with the Thermage system
NASA Astrophysics Data System (ADS)
Tomkoria, Sara; Pope, Karl
2005-04-01
The Thermage ThermaCool TC system is a non-ablative RF device designed to promote tissue tightening and contouring. The system delivers RF energy to a target area under the skin, with volumetric tissue heating in that area. While the amount of energy delivered to a patient can be controlled by ThermaCool system settings, the distribution of energy to the treatment area and underlying layers is variable from individual to individual due to differences in body composition. The present study investigated how local tissue impedance affects the amount of discomfort experienced by patients during RF energy delivery. Discomfort results from heat generation in the treatment area. By using features of the ThermaCool TC System, local impedance (impedance of the treatment area), bulk impedance (impedance of the underlying tissue layers), and total impedance (the sum of local and bulk impedance) were measured for 35 patients. For each patient, impedance measurements were compared to discomfort levels expressed during treatment. Analysis of whole body, local, and bulk impedance values indicate that the percent of total body impedance in the local treatment area contributes to discomfort levels expressed by patients during treatment.
Development of deterministic transport methods for low energy neutrons for shielding in space
NASA Technical Reports Server (NTRS)
Ganapol, Barry
1993-01-01
Transport of low energy neutrons associated with the galactic cosmic ray cascade is analyzed in this dissertation. A benchmark quality analytical algorithm is demonstrated for use with BRYNTRN, a computer program written by the High Energy Physics Division of NASA Langley Research Center, which is used to design and analyze shielding against the radiation created by the cascade. BRYNTRN uses numerical methods to solve the integral transport equations for baryons with the straight-ahead approximation, and numerical and empirical methods to generate the interaction probabilities. The straight-ahead approximation is adequate for charged particles, but not for neutrons. As NASA Langley improves BRYNTRN to include low energy neutrons, a benchmark quality solution is needed for comparison. The neutron transport algorithm demonstrated in this dissertation uses the closed-form Green's function solution to the galactic cosmic ray cascade transport equations to generate a source of neutrons. A basis function expansion for finite heterogeneous and semi-infinite homogeneous slabs with multiple energy groups and isotropic scattering is used to generate neutron fluxes resulting from the cascade. This method, called the FN method, is used to solve the neutral particle linear Boltzmann transport equation. As a demonstration of the algorithm coded in the programs MGSLAB and MGSEMI, neutron and ion fluxes are shown for a beam of fluorine ions at 1000 MeV per nucleon incident on semi-infinite and finite aluminum slabs. Also, to demonstrate that the shielding effectiveness against the radiation from the galactic cosmic ray cascade is not directly proportional to shield thickness, a graph of transmitted total neutron scalar flux versus slab thickness is shown. A simple model based on the nuclear liquid drop assumption is used to generate cross sections for the galactic cosmic ray cascade. The ENDF/B V database is used to generate the total and scattering cross sections for neutrons in aluminum. As an external verification, the results from MGSLAB and MGSEMI were compared to ANISN/PC, a routinely used neutron transport code, showing excellent agreement. In an application to an aluminum shield, the FN method seems to generate reasonable results.
Overall review of feed-in tariff and renewable portfolio standard policy: A perspective of China
NASA Astrophysics Data System (ADS)
Yan, Q. Y.; Zhang, Q.; Yang, L.; Wang, X.
2016-08-01
A major share of China's total carbon dioxide (CO2) emissions is from the electric power sector. To solve this problem, Chinese government has implemented many renewable energy policies in the electric power sector. In China, the most popular renewable energy policies are Feed-in tariff (FIT) and renewable portfolio standard (RPS). This paper first introduces the current development of renewable electricity generation. Second the design plan and implement of FIT and RPS in China's thermal electricity generation sector are summarized in this paper. Third this paper establishes a complementary mode of FIT and RPS which can provide a stable environment to make the FIT and RPS work together. Finally, based on the above analysis, this paper proposes relative suggestions for the implementation of FIT and RPS in China making recommendation for the development of electricity generation from renewable energy.
Sharma, Suhansar Jit; Singh, Tajinder; Singh, Doordarshi; Singh, Amrit; Dhaliwal, A S
2017-12-01
Total bremsstrahlung spectral photon distribution generated in thick targets of lead compounds Pb(CH 3 COO) 2 ·3H 2 O, Pb(NO 3 ) 2 and PbCl 2 by 90 Sr beta particles has been investigated theoretically and experimentally in the photon energy region 1-10keV. The experimental results are compared with the theoretical models describing ordinary bremsstrahlung and the theoretical model which includes polarization bremsstrahlung into ordinary bremsstrahlung, in stripped approximation. It is observed that the experimental results show better agreement with the model which describes bremsstrahlung in stripped approximation in the energy range 3-10keV. However, the results show positive deviation in the photon energy region of 1-3keV. Further, it has been found that there is a continuous decrease of polarization bremsstrahlung contribution into ordinary bremsstrahlung in the formation of total bremsstrahlung spectra with increase in photon energy. The suppression of polarization bremsstrahlung has been observed due to the presence of large fraction of low Z elements in the compounds. The results clearly indicate that polarization bremsstrahlung plays an important role in the formation of total bremsstrahlung spectra in compounds in the studied energy region. Copyright © 2017 Elsevier Ltd. All rights reserved.
Solar electricity: An effective asset to supply urban loads in hot climates
NASA Astrophysics Data System (ADS)
Robert, Fabien Chidanand; Gopalan, Sundararaman
2018-04-01
While human population has been multiplied by four in the last hundred years, the world energy consumption was multiplied by ten. The common method of using fossil fuels to provide energy and electricity has dangerously disturbed nature's and climate's balance. It has become urgent and crucial to find sustainable and eco-friendly alternatives to preserve a livable environment with unpolluted air and water. Renewable energy is the unique eco-friendly opportunity known today. The main challenge of using renewable energy is to ensure the constant balance of electricity demand and generation on the electrical grid. This paper investigates whether the solar electricity generation is correlated with the urban electricity consumption in hot climates. The solar generation and total consumption have been compared for three cities in Florida. The hourly solar generation has been found to be highly correlated with the consumption that occurs 6 h later, while the monthly solar generation is correlated with the monthly energy consumption. Producing 30% of the electricity using solar energy has been found to compensate partly for the monthly variation in the urban electricity demand. In addition, if 30% of the world electricity is produced using solar, global CO2 emissions would be reduced by 11.7% (14.6% for India). Thus, generating 30% solar electricity represents a valuable asset for urban areas situated in hot climates, reducing the need for electrical operating reserve, providing local supply with minimal transmission losses, but above all reducing the need for fossil fuel electricity and reducing global CO2 emission.
Investigation on the possibility of extracting wave energy from the Texas coast
NASA Astrophysics Data System (ADS)
Haces-Fernandez, Francisco
Due to the great and growing demand of energy consumption in the Texas Coast area, the generation of electricity from ocean waves is considered very important. The combination of the wave energy with offshore wind power is explored as a way to increase power output, obtain synergies, maximize the utilization of assigned marine zones and reduce variability. Previously literature has assessed the wave energy generation, combined with wind in different geographic locations such as California, Ireland and the Azores Island. In this research project, the electric power generation from ocean waves on the Texas Coast was investigated, assessing its potential from the meteorological data provided by five buoys from National Data Buoy Center of the National Oceanic and Atmospheric Administration, considering the Pelamis 750 kW Wave Energy Converter (WEC) and the Vesta V90 3 MW Wind Turbine. The power output from wave energy was calculated for the year 2006 using Matlab, and the results in several locations were considered acceptable in terms of total power output, but with a high temporal variability. To reduce its variability, wave energy was combined with wind energy, obtaining a significant reduction on the coefficient of variation on the power output. A Matlab based interface was created to calculate power output and its variability considering data from longer periods of time.
A GRAVITATIONAL DOUBLE-SCATTERING MECHANISM FOR GENERATING HIGH-VELOCITY OBJECTS DURING HALO MERGERS
DOE Office of Scientific and Technical Information (OSTI.GOV)
Samsing, Johan; Department of Astrophysical Sciences, Princeton University, Peyton Hall, Princeton, NJ 08544
2015-02-01
We present a dynamical model that describes how halo particles can receive a significant energy kick from the merger between their own host halo and a target halo. This could provide a possible explanation for some high-velocity objects, including extended systems like globular clusters (GCs). In the model we especially introduce a double-scattering mechanism, where a halo particle receives a significant part of its total energy kick by first undergoing a gravitational deflection by the target halo and subsequently by its original host halo. This generates an energy kick that is due to the relative velocity between the halos duringmore » the deflections. We derive analytically the total kick energy of the particle, which is composed of energy from the double-scattering mechanism and tidal fields, as a function of its position in its original host halo just before merger. In the case of a 1:10 merger, we find that the presented mechanisms can easily generate particles with a velocity approximately two times the virial velocity of the target halo. This motivates us to suggest that the high velocity of the recently discovered GC HVGC-1 can be explained by a head-on halo merger. Finally, we illustrate the orbital evolution of high-velocity particles outside the virial sphere of the target halo by solving the equation of motion in an expanding universe. We find a sweet spot around a scale factor of 0.3-0.5 for ejecting particles into large orbits, which can easily reach beyond approximately five virial radii.« less
Baseline study of methane emission from anaerobic ponds of palm oil mill effluent treatment.
Yacob, Shahrakbah; Ali Hassan, Mohd; Shirai, Yoshihito; Wakisaka, Minato; Subash, Sunderaj
2006-07-31
The world currently obtains its energy from the fossil fuels such as oil, natural gas and coal. However, the international crisis in the Middle East, rapid depletion of fossil fuel reserves as well as climate change have driven the world towards renewable energy sources which are abundant, untapped and environmentally friendly. Malaysia has abundant biomass resources generated from the agricultural industry particularly the large commodity, palm oil. This paper will focus on palm oil mill effluent (POME) as the source of renewable energy from the generation of methane and establish the current methane emission from the anaerobic treatment facility. The emission was measured from two anaerobic ponds in Felda Serting Palm Oil Mill for 52 weeks. The results showed that the methane content was between 35.0% and 70.0% and biogas flow rate ranged between 0.5 and 2.4 L/min/m(2). Total methane emission per anaerobic pond was 1043.1 kg/day. The total methane emission calculated from the two equations derived from relationships between methane emission and total carbon removal and POME discharged were comparable with field measurement. This study also revealed that anaerobic pond system is more efficient than open digesting tank system for POME treatment. Two main factors affecting the methane emission were mill activities and oil palm seasonal cropping.
High Temperature Fusion Reactor Cooling Using Brayton Cycle Based Partial Energy Conversion
NASA Technical Reports Server (NTRS)
Juhasz, Albert J.; Sawicki, Jerzy T.
2003-01-01
For some future space power systems using high temperature nuclear heat sources most of the output energy will be used in other than electrical form, and only a fraction of the total thermal energy generated will need to be converted to electrical work. The paper describes the conceptual design of such a partial energy conversion system, consisting of a high temperature fusion reactor operating in series with a high temperature radiator and in parallel with dual closed cycle gas turbine (CCGT) power systems, also referred to as closed Brayton cycle (CBC) systems, which are supplied with a fraction of the reactor thermal energy for conversion to electric power. Most of the fusion reactor's output is in the form of charged plasma which is expanded through a magnetic nozzle of the interplanetary propulsion system. Reactor heat energy is ducted to the high temperature series radiator utilizing the electric power generated to drive a helium gas circulation fan. In addition to discussing the thermodynamic aspects of the system design the authors include a brief overview of the gas turbine and fan rotor-dynamics and proposed bearing support technology along with performance characteristics of the three phase AC electric power generator and fan drive motor.
High Temperature Fusion Reactor Cooling Using Brayton Cycle Based Partial Energy Conversion
NASA Astrophysics Data System (ADS)
Juhasz, Albert J.; Sawicki, Jerzy T.
2004-02-01
For some future space power systems using high temperature nuclear heat sources most of the output energy will be used in other than electrical form, and only a fraction of the total thermal energy generated will need to be converted to electrical work. The paper describes the conceptual design of such a ``partial energy conversion'' system, consisting of a high temperature fusion reactor operating in series with a high temperature radiator and in parallel with dual closed cycle gas turbine (CCGT) power systems, also referred to as closed Brayton cycle (CBC) systems, which are supplied with a fraction of the reactor thermal energy for conversion to electric power. Most of the fusion reactor's output is in the form of charged plasma which is expanded through a magnetic nozzle of the interplanetary propulsion system. Reactor heat energy is ducted to the high temperature series radiator utilizing the electric power generated to drive a helium gas circulation fan. In addition to discussing the thermodynamic aspects of the system design the authors include a brief overview of the gas turbine and fan rotor-dynamics and proposed bearing support technology along with performance characteristics of the three phase AC electric power generator and fan drive motor.
[Carbon footprint in five third-level health care centers in Peru, 2013].
Bambarén-Alatrista, Celso; Alatrista-Gutiérrez, María Del Socorro
2016-06-01
This study was performed to calculate the carbon footprint generated by third-level health care centers located in Lima, Peru, in 2013. Reports were obtained on the consumption of energy resources and water as well as on waste generation from the five centers, which contributed to climate change with an emission of 14,462 teq of CO2. A total of 46% of these emissions were associated with fuel consumption by the powerhouse, power generators, and transport vehicles; 44% was related to energy consumption; and the remaining 10% was related to the use of water and generation of solid hospital waste. CO2, N2O, and CH4 are the greenhouse gases included in the estimated carbon footprint. Our results show that hospitals have a negative environmental impact, mainly due to fossil fuel consumption.
Current redistribution and generation of kinetic energy in the stagnated Z pinch.
Ivanov, V V; Anderson, A A; Papp, D; Astanovitskiy, A L; Talbot, B R; Chittenden, J P; Niasse, N
2013-07-01
The structure of magnetic fields was investigated in stagnated wire-array Z pinches using a Faraday rotation diagnostic at the wavelength of 266 nm. The distribution of current in the pinch and trailing material was reconstructed. A significant part of current can switch from the main pinch to the trailing plasma preheated by x-ray radiation of the pinch. Secondary implosions of trailing plasma generate kinetic energy and provide enhanced heating and radiation of plasma at stagnation. Hot spots in wire-array Z pinches also provide enhanced radiation of the Z pinch. A collapse of a single hot spot radiates 1%-3% of x-ray energy of the Z pinch with a total contribution of hot spots of 10%-30%.
A feasibility study on solar utility total energy system /SUTES/
NASA Astrophysics Data System (ADS)
Bilgen, E.
1980-11-01
A fully dedicated central receiver solar utility (CRSU) designed to meet domestic energy requirements for space heating and hot water has been synthesized and assessed at the conceptual level. The solar utility total energy system (SUTES) integrates (1) a central receiver solar utility (CRSU), (2) an electrical power generating system (EPGS), (3) a hydrogen production plant (HPP), (4) a water chilling system for cooling, heat pump system (HPS), (5) necessary thermal energy storage systems (TES), (6) a district heating and cooling system (DH&CS). All subsystems are close-coupled. Using consistent costing bases, it has been found that the SUTES concept provides energy costs which are lower than those provided by a CRSU. Representative costs are $3.14/GJ versus $8.56/GJ for 10 percent recovery factor and $12.55/GJ versus $13.47/GJ for 17.5 percent recovery factor.
NASA Technical Reports Server (NTRS)
1980-01-01
Present and future relatively small (30 MW) energy systems, such as solar thermal electric, photovoltaic, wind, fuel cell, storage battery, hydro, and cogeneration can help achieve national energy goals and can be dispersed throughout the distribution portion of an electric utility system. Based on current projections, it appears that dispersed storage and generation (DSG) electrical energy will comprise only a small portion, from 4 to 10 percent, of the national total by the end of this century. In general, the growth potential for DSG seems favorable in the long term because of finite fossil energy resources and increasing fuel prices. Recent trends, especially in the institutional and regulatory fields, favor greater use of the DSGs for the future.
NASA Astrophysics Data System (ADS)
1980-10-01
Present and future relatively small (30 MW) energy systems, such as solar thermal electric, photovoltaic, wind, fuel cell, storage battery, hydro, and cogeneration can help achieve national energy goals and can be dispersed throughout the distribution portion of an electric utility system. Based on current projections, it appears that dispersed storage and generation (DSG) electrical energy will comprise only a small portion, from 4 to 10 percent, of the national total by the end of this century. In general, the growth potential for DSG seems favorable in the long term because of finite fossil energy resources and increasing fuel prices. Recent trends, especially in the institutional and regulatory fields, favor greater use of the DSGs for the future.
DOE Office of Scientific and Technical Information (OSTI.GOV)
None
2015-04-02
The Water Power Program helps industry harness this renewable, emissions-free resource to generate environmentally sustainable and cost-effective electricity. Through support for public, private, and nonprofit efforts, the Water Power Program promotes the development, demonstration, and deployment of advanced hydropower devices and pumped storage hydropower applications. These technologies help capture energy stored by diversionary structures, increase the efficiency of hydroelectric generation, and use excess grid energy to replenish storage reserves for use during periods of peak electricity demand. In addition, the Water Power Program works to assess the potential extractable energy from domestic water resources to assist industry and government inmore » planning for our nation’s energy future. From FY 2008 to FY 2014, DOE’s Water Power Program announced awards totaling approximately $62.5 million to 33 projects focused on hydropower. Table 1 provides a brief description of these projects.« less
Assessment of agricultural biomass potential to electricity generation in Riau Province
NASA Astrophysics Data System (ADS)
Papilo, P.; Kusumanto, I.; Kunaifi, K.
2017-05-01
Utilization of biomass as a source of electrical power is one potential solution that can be developed in order to increase of the electrification ratio and to Achieve the national energy security. However, now it is still difficult, to Determine the amount of potential energy that can be used as an alternative power generation. Therefore, as a preliminary step to assess the feasibility of biomass development as a power generation source, an analysis of potential resources are required, especially from some of the main commodities, both of residues of agriculture and plantation. This study aims to assessing the potential of biomass-based supply from unutilized resources that can be Obtained from the residues of agricultural and plantations sectors, such as rice straw and rice husk; Dry straw and chaff of rice; corn stalks and cobs; stalks of cassava; and fiber, shell, empty fruit Bunches, kernels and liquid wastes in the palm oil factories. More research is focused on the theoretical energy potential measurements using a statistical approach which has been developed by Biomass Energy Europe (BEE). Results of the assessment has been done and showed that the total theoretical biomass energy that can be produced is equal to 77,466,754.8 Gj year -1. Theoretically, this potential is equivalent to generate electricityof year 21,518,542.8 MWh -1.
Solar Total Energy Project (STEP) Performance Analysis of High Temperature Energy Storage Subsystem
NASA Technical Reports Server (NTRS)
Moore, D. M.
1984-01-01
The 1982 milestones and lessons learned; performance in 1983; a typical day's operation; collector field performance and thermal losses; and formal testing are highlighted. An initial test that involves characterizing the high temperature storage (hts) subsystem is emphasized. The primary element is on 11,000 gallon storage tank that provides energy to the steam generator during transient solar conditions or extends operating time. Overnight, thermal losses were analyzed. The length of time the system is operated at various levels of cogeneration using stored energy is reviewed.
Novel Anaerobic Wastewater Treatment System for Energy Generation at Forward Operating Bases
2016-08-01
AnMBR) technology with clinoptilolite ion exchange and GreenBox™ ammonia electrolysis. The system generates both methane and hydrogen fuels...experimental setup. ................................................ 21 Figure 10. Methane phase semi batch experimental setup, a total of three reactors were...set up for PS + solid, Bioc and ADS methane phase reactors. .................... 21 Figure 11. Dried PS solid for the control, Bioc blend for the
Nagy-Balo, Edina; Kiss, Alexandra; Condie, Catherine; Stewart, Mark; Edes, Istvan; Csanadi, Zoltan
2014-06-01
Pulmonary vein isolation with phased radiofrequency current and use of a pulmonary vein ablation catheter (PVAC) has recently been associated with a high incidence of clinically silent brain infarcts on diffusion-weighted magnetic resonance imaging and a high microembolic signal (MES) count detected by transcranial Doppler. The purpose of this study was to investigate the potential correlation between different biophysical parameters of energy delivery (ED) and MES generation during PVAC ablation. MES counts during consecutive PVAC ablations were recorded for each ED and time stamped for correlation with temperature, power, and impedance data from the GENius 14.4 generator. Additionally, catheter-tissue contact was characterized by the template deviation score, calculated by comparing the temperature curve with an ideal template representing good contact, and by the respiratory contact failure score, to quantify temperature variations indicative of intermittent contact due to respiration. A total of 834 EDs during 48 PVAC ablations were analyzed. A significant increase in MES count was associated with a lower average temperature, a temperature integral over 62°C, a higher average power, the total energy delivered, higher respiration and template deviation scores (P <.0001), and simultaneous ED to the most proximal and distal poles of the PVAC (P <.0001). MES generation during ablation is related to different indicators of poor electrode-tissue contact, the total power delivered, and the interaction between the most distal and the most proximal electrodes. Copyright © 2014. Published by Elsevier Inc.
Midinfrared radiation energy harvesting device
NASA Astrophysics Data System (ADS)
Lin, Hong-Ren; Wang, Wei-Chih
2017-07-01
The International Energy Agency reports a 17.6% annual growth rate in sustainable energy production. However, sustainable power generation based on environmental conditions (wind and solar) requires an infrastructure that can handle intermittent power generation. An electromagnetic thermoelectric (EMTE) device to overcome the intermittency problems of current sustainable energy technologies, providing the continuous supply unachievable by photovoltaic cells with portability impossible for traditional thermoelectric (TE) generators, is proposed. The EMTE converts environmental electromagnetic waves to a voltage output without requiring additional input. A single cell of this TE-inspired broadband EMTE can generate a 19.50 nV output within a 7.2-μm2 area, with a verified linear scalability of the output voltage through cell addition. This idea leads to a challenge: the electrical polarity of each row of cells is the same but may require additional routing to combine output from each row. An innovative layout is proposed to overcome this issue through switching the electrical polarity every other row. In this scheme, the EM wave absorption spectrum is not altered, and a simple series connection can be implemented to boost the total voltage output by 1 order within a limited area.
DOE Office of Scientific and Technical Information (OSTI.GOV)
McMillan, Colin A.; Boardman, Richard; McKellar, Michael
The industrial sector was the third-largest source of direct U.S. greenhouse gas (GHG) emissions in 2014 behind electricity generation and transportation and accounted for roughly 20% of total emissions (EPA 2016). The Energy Information Administration (EIA) projects that total U.S. energy consumption will grow to about 108 exajoules (1 EJ = 10 18 J) or 102 quads (1 quad = 10 15 British thermal units) in 2025, with nearly all of the growth coming from the industrial sector (DOE 2015b). Energy consumption in the industrial sector is forecast to increase to 39.5 EJ (37.4 quads)—a 22% increase, exceeding 36% ofmore » total energy consumption in the United States. Therefore, it is imperative that industrial GHG emissions be considered in any strategy intent on achieving deep decarbonization of the energy sector as a whole. It is important to note that unlike the transportation sector and electrical grid, energy use by industry often involves direct conversion of primary energy sources to thermal and electrical energy at the point of consumption. About 52% of U.S. industrial direct GHG emissions are the result of fuel combustion (EPA 2016) to produce hot gases and steam for process heating, process reactions, and process evaporation, concentration, and drying. The heterogeneity and variations in scale of U.S. industry and the complexity of modern industrial firms’ global supply chains are among the sector’s unique challenges to minimizing its GHG emissions. A combination of varied strategies—such as energy efficiency, material efficiency, and switching to low-carbon fuels—can help reduce absolute industrial GHG emissions. This report provides a complement to process-efficiency improvement to consider how clean energy delivery and use by industry could reduce GHG emissions. Specifically, it considers the possibility of replacing fossil-fuel combustion in industry with nuclear (specifically small modular reactors [SMRs]), solar thermal (referred to herein as solar industrial process heat [SIPH]), and geothermal energy sources. The possibility of applying electrical heating and greater use of hydrogen is also considered, although these opportunities are not discussed in as much detail.« less
NASA Astrophysics Data System (ADS)
Duke, D. L.; Tovesson, F.; Brys, T.; Geppert-Kleinrath, V.; Hambsch, F.-J.; Laptev, A.; Meharchand, R.; Manning, B.; Mayorov, D.; Meierbachtol, K.; Mosby, S.; Perdue, B.; Richman, D.; Shields, D.; Vidali, M.
2017-09-01
The average Total Kinetic Energy (TKE) release and fission-fragment yields in neutron-induced fission of 235U and 238U was measured using a Frisch-gridded ionization chamber. These observables are important nuclear data quantites that are relevant to applications and for informing the next generation of fission models. The measurements were performed a the Los Alamos Neutron Science Center and cover En = 200 keV - 30 MeV. The double-energy (2E) method was used to determine the fission-fragment yields and two methods of correcting for prompt-neutron emission were explored. The results of this study are correlated mass and TKE data.
The spectrum of high-energy cosmic rays measured with KASCADE-Grande
NASA Astrophysics Data System (ADS)
Apel, W. D.; Arteaga-Velázquez, J. C.; Bekk, K.; Bertaina, M.; Blümer, J.; Bozdog, H.; Brancus, I. M.; Buchholz, P.; Cantoni, E.; Chiavassa, A.; Cossavella, F.; Daumiller, K.; de Souza, V.; Di Pierro, F.; Doll, P.; Engel, R.; Engler, J.; Finger, M.; Fuhrmann, D.; Ghia, P. L.; Gils, H. J.; Glasstetter, R.; Grupen, C.; Haungs, A.; Heck, D.; Hörandel, J. R.; Huber, D.; Huege, T.; Kampert, K.-H.; Kang, D.; Kickelbick, D.; Klages, H. O.; Link, K.; Łuczak, P.; Ludwig, M.; Mathes, H. J.; Mayer, H. J.; Melissas, M.; Milke, J.; Mitrica, B.; Morello, C.; Navarra, G.; Oehlschläger, J.; Ostapchenko, S.; Over, S.; Palmieri, N.; Petcu, M.; Pierog, T.; Rebel, H.; Roth, M.; Schieler, H.; Schröder, F. G.; Sima, O.; Toma, G.; Trinchero, G. C.; Ulrich, H.; Weindl, A.; Wochele, J.; Wommer, M.; Zabierowski, J.
2012-08-01
The energy spectrum of cosmic rays between 1016 eV and 1018 eV, derived from measurements of the shower size (total number of charged particles) and the total muon number of extensive air showers by the KASCADE-Grande experiment, is described. The resulting all-particle energy spectrum exhibits strong hints for a hardening of the spectrum at approximately 2 · 1016 eV and a significant steepening at ≈8 · 1016 eV. These observations challenge the view that the spectrum is a single power law between knee and ankle. Possible scenarios generating such features are discussed in terms of astrophysical processes that may explain the transition region from galactic to extragalactic origin of cosmic rays.
DOE Office of Scientific and Technical Information (OSTI.GOV)
PNNL
Case study describes how the Army Reserve 9th Mission Support Command (MSC) reduced lighting energy consumption by 62% for a total savings of 125,000 kWh and more than $50,000 per year by replacing over 400 fluorescent troffers with 36 W LED troffers. This project was part of the Army Reserve Net Zero Pilot Program, initiated in 2013, to reduce energy and water consumption, waste generation, and utility costs.
Calculating electronic correlation effects from densities of transitions
NASA Astrophysics Data System (ADS)
Haydock, Roger
Adding a localized electron to a system of interacting electrons induces a density of transitions described by the time-independent Heisenberg equation. Sequences of these transitions generate interacting states whose total energy is the sum of energies of the constituent transitions. A calculation of magnetic moments for itinerant electrons with Ising interactions illustrates this method. supported by the H. V. Snyder Gift to the University of Oregon.
Federal Register 2010, 2011, 2012, 2013, 2014
2013-05-13
... Kaplan turbine and generator; and (4) appurtenant facilities. The proposed project would have a total..., Tampa, Florida 33602, phone: (403) 618-2018. FERC Contact: Corey Vezina; phone: (202) 502-8598, email...
Energy conservation through sealing technology
NASA Technical Reports Server (NTRS)
Stair, W. K.; Ludwig, L. P.
1978-01-01
Improvements in fluid film sealing resulting from a proposed research program could lead to an annual energy saving, on a national basis, equivalent to about 37 million bbl of oil or 0.3% of the total U.S. energy consumption. Further, the application of known sealing technology can result in an annual saving of an additional 10 million bbl of oil. The energy saving would be accomplished by reduction in process heat energy loss, reduction of frictional energy generated, and minimization of energy required to operate ancillary equipment associated with the seal system. In addition to energy saving, cost effectiveness is further enhanced by reduction in maintenance and in minimization of equipment for collecting leakage and for meeting environmental pollution standards.
Thermal energy harvesting and solar energy conversion utilizing carbon-based nanomaterials
NASA Astrophysics Data System (ADS)
McCarthy, Patrick T.
This dissertation provides details of carbon-based nanomaterial fabrication for applications in energy harvesting and generation. As energy demands increase, and concerns about mankind's environmental impact increase, alternative methods of generating energy will be widely researched. Carbon-based nanomaterials may be effective in such applications as their fabrication is often inexpensive and they have highly desirable electrical, mechanical, and thermal properties. Synthesis and characterization of carbon nanotube thermal interfaces on gadolinium foils is described herein. Total thermal interface resistances of carbon nanotube coated gadolinium were measured using a one-dimensional reference calorimeter technique, and the effect of hydrogen embrittlement on the magnetic properties of gadolinium foils is discussed. The samples generated in this study were consistently measured with reduced total thermal interface resistances of 55-70% compared to bare gadolinium. Characterization of gadolinium foils in a cooling device called a magneto thermoelectric generator was also performed. A gadolinium shuttle drives the device as it transitions between ferromagnetic and paramagnetic states. Reduced interface resistances from the carbon nanotube arrays led to increased shuttle frequency and effective heat transfer coefficients. Detailed theoretical derivations for electron emission during thermal and photo-excitation are provided for both three-dimensional and two-dimensional materials. The derived theories were fitted to experimental data from variable temperature photoemission studies of potassium-intercalated graphitic nanopetals. A work function reduction from approximately 4.5 eV to 2 -- 3 eV resulted from potassium intercalation and adsorption. While changes in the electron energy distribution shape and intensity were significant within 310 -- 680 K, potassium-intercalated graphitic petals demonstrate very high thermal stability after heating to nearly 1000 K. Boron nitride modification of the nanopetals was performed in an effort to minimize deintercalation of potassium from the nanopetal lattice and while multiple work functions were present within the electron energy distribution, massive reductions in emission intensity took place above 580 K. Finally, a device for measuring the current density during photoemission was also developed and photoemission induced by a solar simulator at room temperature produced currents on the order of 1 nA/cm 2 resulting in a quantum efficiency of approximately 8.0x10 --8 electrons emitted per photon of illumination.
1993-02-01
Fueled 7,634,0(X) 51 Geothermal 1,302,M(K) 9 Nuclear 2,160,(MX) 14 Total Thermal 11,096,(kM) 74 Hydroelectric 3,877,M(X) 26 Solar 0 0t Total Company...Nuclear 16,273,963 17 "Total Thermal 48,094,316 50 Hydroelectric 8,007,631 8 Solar 35 0 Total Company Generation 56,101,982 58 Helms Pumpback Energy...returnable beverage containers, prohibition of disposable diapers , and other measures to reduce the volume of the urban solid waste streams. Appeaidix 19-B
Tsai, Jen-Hsiung; Chen, Shui-Jen; Huang, Kuo-Lin; Lee, Wen-Jhy; Kuo, Wen-Chien; Lin, Wen-Yinn
2011-01-01
This study investigated the particulate matter (PM), particle-bound carbons, and polycyclic aromatic hydrocarbons (PAHs) emitted from a diesel-engine generator fuelled with blends of pure fossil diesel oil (D100) and varying percentages of waste-edible-oil biodiesel (W10, 10 vol %; W20, 20 vol %; W30, 30 vol %; and W50, 50 vol %) under generator loads of 0, 1.5, and 3 kW. On average, the PM emission factors of all blends was 30.5 % (range, 13.7-52.3 %) lower than that of D100 under the tested loads. Substituting pure fossil diesel oil with varying percentages of waste-edible-oil biodiesel reduced emissions of particle-bound total carbon (TC) and elemental carbon (EC). The W20 blend had the lowest particle-bound organic carbon (OC) emissions. Notably, W10, W20, and W30 also had lower Total-PAH emissions and lower total equivalent toxicity (Total-BaP(eq)) compared to D100. Additionally, the brake-specific fuel consumption of the generator correlated positively with the ratio of waste-edible-oil biodiesel to pure fossil diesel. However, generator energy efficiency correlated negatively with the ratio of waste-edible-oil biodiesel to pure fossil diesel.
Ryder, Robert T.; Qiang, Jin; McCabe, Peter J.; Nuccio, Vito F.; Persits, Felix
2012-01-01
This report discusses the geologic framework and petroleum geology used to assess undiscovered petroleum resources in the Bohaiwan basin province for the 2000 World Energy Assessment Project of the U.S. Geological Survey. The Bohaiwan basin in northeastern China is the largest petroleum-producing region in China. Two total petroleum systems have been identified in the basin. The first, the Shahejie&ndashShahejie/Guantao/Wumishan Total Petroleum System, involves oil and gas generated from mature pods of lacustrine source rock that are associated with six major rift-controlled subbasins. Two assessment units are defined in this total petroleum system: (1) a Tertiary lacustrine assessment unit consisting of sandstone reservoirs interbedded with lacustrine shale source rocks, and (2) a pre-Tertiary buried hills assessment unit consisting of carbonate reservoirs that are overlain unconformably by Tertiary lacustrine shale source rocks. The second total petroleum system identified in the Bohaiwan basin is the Carboniferous/Permian Coal–Paleozoic Total Petroleum System, a hypothetical total petroleum system involving natural gas generated from multiple pods of thermally mature coal beds. Low-permeability Permian sandstones and possibly Carboniferous coal beds are the reservoir rocks. Most of the natural gas is inferred to be trapped in continuous accumulations near the center of the subbasins. This total petroleum system is largely unexplored and has good potential for undiscovered gas accumulations. One assessment unit, coal-sourced gas, is defined in this total petroleum system.
Using Photovoltaic (PV) Cells on Enduring DoD Installations in the Middle East: A Feasibility Study
2013-06-01
geothermal , and biomass). In FY 2009, 3.6 percent of the DoD’s electrical consumption came from renewable electricity sources, exceeding the EP Act 2005...defined as electrical energy generated from solar, wind, biomass, landfill gas, ocean (including tidal, wave, current, and thermal), geothermal ...involving solar, wind, geothermal and biomass energy. The U.S. Navy accounts for 60 percent of DoD’s renewable energy projects—some 250 in total. The 14
Consonni, S; Giugliano, M; Grosso, M
2005-01-01
This two-part paper assesses four strategies for energy recovery from municipal solid waste (MSW) by dedicated waste-to-energy (WTE) plants generating electricity through a steam cycle. The feedstock is the residue after materials recovery (MR), assumed to be 35% by weight of the collected MSW. In strategy 1, the MR residue is fed directly to a grate combustor. In strategy 2, the MR residue is first subjected to light mechanical treatment. In strategies 3 and 4, the MR residue is converted into RDF, which is combusted in a fluidized bed combustor. To examine the relevance of scale, we considered a small waste management system (WMS) serving 200,000 people and a large WMS serving 1,200,000 people. A variation of strategy 1 shows the potential of cogeneration with district heating. The assessment is carried out by a Life Cycle Analysis where the electricity generated by the WTE plant displaces electricity generated by fossil fuel-fired steam plants. Part A focuses on mass and energy balances, while Part B focuses on emissions and costs. Results show that treating the MR residue ahead of the WTE plant reduces energy recovery. The largest energy savings are achieved by combusting the MR residue "as is" in large scale plants; with cogeneration, primary energy savings can reach 2.5% of total societal energy use.
Analysis of the economics of photovoltaic-diesel-battery energy systems for remote applications
NASA Technical Reports Server (NTRS)
Brainard, W. A.
1983-01-01
Computer simulations were conducted to analyze the performance and operating cost of a photovoltaic energy source combined with a diesel generator system and battery storage. The simulations were based on the load demand profiles used for the design of an all photovoltaic energy system installed in the remote Papago Indian Village of Schuchuli, Arizona. Twenty year simulations were run using solar insolation data from Phoenix SOLMET tapes. Total energy produced, energy consumed, operation and maintenance costs were calculated. The life cycle and levelized energy costs were determined for a variety of system configurations (i.e., varying amounts of photovoltaic array and battery storage).
Efficiency of centrifugal mechanism in producing PeV neutrinos from active galactic nuclei
NASA Astrophysics Data System (ADS)
Osmanov, Zaza; Mahajan, Swadesh; Machabeli, George; Chkheidze, Nino
2018-05-01
A several-step theoretical model is constructed to trace the origin of ultra high energy (UHE) [ 1 - 2 ] PeV neutrinos detected, recently, by the IceCube collaboration. Protons in the AGN magnetosphere, experiencing different gravitational centrifugal force, provide free energy for the parametric excitation of Langmuir waves via a generalized two-stream instability. Landau damping of these waves, outside the AGN magnetosphere, can accelerate protons to ultra high energies. The ultimate source for this mechanism, the Langmuir-Landau-Centrifugal-Drive (LLCD), is the gravitational energy of the compact object. The LLCD generated UHE protons provide the essential ingredient in the creation of UHE neutrinos via appropriate hadronic reactions; protons of energy 1017 eV can be generated in the plasmas surrounding AGN with bolometric luminosities of the order of 1043 ergs s-1. By estimating the diffusive energy flux of extragalactic neutrinos in the energy interval [ 1 - 2 ] PeV, we find that an acceptably small fraction 0.003% of the total bolometric luminosity will suffice to create the observed fluxes of extragalactic ultra-high energy neutrinos.
NASA Technical Reports Server (NTRS)
Fuelberg, H. E.; Browning, P. A.
1983-01-01
Contributions of divergent and rotational wind components to the synoptic-scale kinetic energy balance are described using rawinsonde data at 3 and 6 h intervals from NASA's fourth Atmospheric Variability experiment. Two intense thunderstorm complexes occurred during the period. Energy budgets are described for the entire computational region and for limited volumes that enclosed storm-induced, upper level wind maxima located poleward of convection. Although small in magnitude, the divergent wind component played an important role in the cross-contour generation and horizontal flux divergence of kinetic energy. The importance of V(D) appears directly related to the presence and intensity of convection. Although K(D) usually comprised less than 10 percent of the total kinetic energy content, generation of kinetic energy by V(D) was a major factor in the creation of upper-level wind maxima to the north of the storm complexes. Omission of the divergent wind apparently would lead to serious misrepresentations of the energy balance. A random error analysis is presented to assess confidence limits in the various energy parameters.
Drought Resilience of Water Supplies for Shale Gas Extraction and Related Power Generation in Texas
NASA Astrophysics Data System (ADS)
Reedy, R. C.; Scanlon, B. R.; Nicot, J. P.; Uhlman, K.
2014-12-01
There is considerable concern about water availability to support energy production in Texas, particularly considering that many of the shale plays are in semiarid areas of Texas and the state experienced the most extreme drought on record in 2011. The Eagle Ford shale play provides an excellent case study. Hydraulic fracturing water use for shale gas extraction in the play totaled ~ 12 billion gallons (bgal) in 2012, representing ~7 - 10% of total water use in the 16 county play area. The dominant source of water is groundwater which is not highly vulnerable to drought from a recharge perspective because water is primarily stored in the confined portion of aquifers that were recharged thousands of years ago. Water supply drought vulnerability results primarily from increased water use for irrigation. Irrigation water use in the Eagle Ford play was 30 billion gallons higher in the 2011 drought year relative to 2010. Recent trends toward increased use of brackish groundwater for shale gas extraction in the Eagle Ford also reduce pressure on fresh water resources. Evaluating the impacts of natural gas development on water resources should consider the use of natural gas in power generation, which now represents 50% of power generation in Texas. Water consumed in extracting the natural gas required for power generation is equivalent to ~7% of the water consumed in cooling these power plants in the state. However, natural gas production from shale plays can be overall beneficial in terms of water resources in the state because natural gas combined cycle power generation decreases water consumption by ~60% relative to traditional coal, nuclear, and natural gas plants that use steam turbine generation. This reduced water consumption enhances drought resilience of power generation in the state. In addition, natural gas combined cycle plants provide peaking capacity that complements increasing renewable wind generation which has no cooling water requirement. However, water savings related to power generation is not collocated with water used for shale gas extraction. Analysis of drought impacts on water energy interdependence should consider both water for energy extraction and power generation to assess net impacts.
NASA Astrophysics Data System (ADS)
Li, Xiayue; Curtis, Farren S.; Rose, Timothy; Schober, Christoph; Vazquez-Mayagoitia, Alvaro; Reuter, Karsten; Oberhofer, Harald; Marom, Noa
2018-06-01
We present Genarris, a Python package that performs configuration space screening for molecular crystals of rigid molecules by random sampling with physical constraints. For fast energy evaluations, Genarris employs a Harris approximation, whereby the total density of a molecular crystal is constructed via superposition of single molecule densities. Dispersion-inclusive density functional theory is then used for the Harris density without performing a self-consistency cycle. Genarris uses machine learning for clustering, based on a relative coordinate descriptor developed specifically for molecular crystals, which is shown to be robust in identifying packing motif similarity. In addition to random structure generation, Genarris offers three workflows based on different sequences of successive clustering and selection steps: the "Rigorous" workflow is an exhaustive exploration of the potential energy landscape, the "Energy" workflow produces a set of low energy structures, and the "Diverse" workflow produces a maximally diverse set of structures. The latter is recommended for generating initial populations for genetic algorithms. Here, the implementation of Genarris is reported and its application is demonstrated for three test cases.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Diakov, Victor; Brinkman, Gregory; Denholm, Paul
Using production-cost model (PLEXOS), we simulate the Western Interchange (WECC) at several levels of the yearly renewable energy (RE) generation, between 13% and 40% of the total load for the year. We look at the overall energy exchange between a region and the rest of the system (net interchange, NI), and find it useful to examine separately (i) (time-)variable and (ii) year-average components of the NI. Both contribute to inter-regional energy exchange, and are affected by wind and PV generation in the system. We find that net load variability (in relatively large portions of WECC) is the leading factor affectingmore » the variable component of inter-regional energy exchange, and the effect is quantifiable: higher regional net load correlation with the rest of the WECC lowers net interchange variability. Further, as the power mix significantly varies between WECC regions, effects of ‘flexibility import’ (regions ‘borrow’ ramping capability) are also observed.« less
Reducing US Oil Dependence Using Simulation
NASA Technical Reports Server (NTRS)
Ayoub, Fadi; Arnaout, Georges M.
2011-01-01
People across the world are addicted to oil; as a result, the instability of oil prices and the shortage of oil reserves have influenced human behaviors and global businesses. Today, the United States makes up only 5% of the global population but consumes 25% of the. world total energy. Most of this energy is generated from fossil fuels in the form of electricity. The contribution of this paper is to examine the possibilities of replacing fossil fuel with renewable energies to generate electricity as well as to examine other methods to reduce oil and gas consumption. We propose a system dynamics model in an attempt to predict the future US dependence on fossil fuels by using renewable energy resources such as, nuclear, wind, solar, and hydro powers. Based on the findings of our model, the study expects to provide insights towards promising solutions of the oil dependency problem.
Chassin, David P.; Behboodi, Sahand; Djilali, Ned
2018-01-28
This article proposes a system-wide optimal resource dispatch strategy that enables a shift from a primarily energy cost-based approach, to a strategy using simultaneous price signals for energy, power and ramping behavior. A formal method to compute the optimal sub-hourly power trajectory is derived for a system when the price of energy and ramping are both significant. Optimal control functions are obtained in both time and frequency domains, and a discrete-time solution suitable for periodic feedback control systems is presented. The method is applied to North America Western Interconnection for the planning year 2024, and it is shown that anmore » optimal dispatch strategy that simultaneously considers both the cost of energy and the cost of ramping leads to significant cost savings in systems with high levels of renewable generation: the savings exceed 25% of the total system operating cost for a 50% renewables scenario.« less
An optimization model for energy generation and distribution in a dynamic facility
NASA Technical Reports Server (NTRS)
Lansing, F. L.
1981-01-01
An analytical model is described using linear programming for the optimum generation and distribution of energy demands among competing energy resources and different economic criteria. The model, which will be used as a general engineering tool in the analysis of the Deep Space Network ground facility, considers several essential decisions for better design and operation. The decisions sought for the particular energy application include: the optimum time to build an assembly of elements, inclusion of a storage medium of some type, and the size or capacity of the elements that will minimize the total life-cycle cost over a given number of years. The model, which is structured in multiple time divisions, employ the decomposition principle for large-size matrices, the branch-and-bound method in mixed-integer programming, and the revised simplex technique for efficient and economic computer use.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chassin, David P.; Behboodi, Sahand; Djilali, Ned
This article proposes a system-wide optimal resource dispatch strategy that enables a shift from a primarily energy cost-based approach, to a strategy using simultaneous price signals for energy, power and ramping behavior. A formal method to compute the optimal sub-hourly power trajectory is derived for a system when the price of energy and ramping are both significant. Optimal control functions are obtained in both time and frequency domains, and a discrete-time solution suitable for periodic feedback control systems is presented. The method is applied to North America Western Interconnection for the planning year 2024, and it is shown that anmore » optimal dispatch strategy that simultaneously considers both the cost of energy and the cost of ramping leads to significant cost savings in systems with high levels of renewable generation: the savings exceed 25% of the total system operating cost for a 50% renewables scenario.« less
NASA Astrophysics Data System (ADS)
Ogino, Jumpei; Miyamoto, Sho; Matsuyama, Takahiro; Sueda, Keiichi; Yoshida, Hidetsugu; Tsubakimoto, Koji; Miyanaga, Noriaki
2014-12-01
We demonstrate optical parametric chirped-pulse amplification (OPCPA) based on two-beam pumping, using sub-nanosecond pulses generated by stimulated Brillouin scattering compression. Seed pulse energy, duration, and center wavelength were 5 nJ, 220 ps, and ˜1065 nm, respectively. The 532 nm pulse from a Q-switched Nd:YAG laser was compressed to ˜400 ps in heavy fluorocarbon FC-40 liquid. Stacking of two time-delayed pump pulses reduced the amplifier gain fluctuation. Using a walk-off-compensated two-stage OPCPA at a pump energy of 34 mJ, a total gain of 1.6 × 105 was obtained, yielding an output energy of 0.8 mJ. The amplified chirped pulse was compressed to 97 fs.
NASA Astrophysics Data System (ADS)
Lemos, N.; Albert, F.; Shaw, J. L.; Papp, D.; Polanek, R.; King, P.; Milder, A. L.; Marsh, K. A.; Pak, A.; Pollock, B. B.; Hegelich, B. M.; Moody, J. D.; Park, J.; Tommasini, R.; Williams, G. J.; Chen, Hui; Joshi, C.
2018-05-01
An x-ray source generated by an electron beam produced using a Self-Modulated Laser Wakefield Accelerator (SM-LWFA) is explored for use in high energy density science facilities. By colliding the electron beam, with a maximum energy of 380 MeV, total charge of >10 nC and a divergence of 64 × 100 mrad, from a SM-LWFA driven by a 1 ps 120 J laser, into a high-Z foil, an x/gamma-ray source was generated. A broadband bremsstrahlung energy spectrum with temperatures ranging from 0.8 to 2 MeV was measured with an almost 2 orders of magnitude flux increase when compared with other schemes using LWFA. GEANT4 simulations were done to calculate the source size and divergence.
Urinary extracorporeal shock wave lithotripsy: equipment, techniques, and overview.
Pfister, R C; Papanicolaou, N; Yoder, I C
1988-01-01
Second generation urinary lithotriptors are characterized by extensive technical alterations and significant equipment improvement in the functional, logistical, and medical aspects of shock wave lithotripsy (SWL). These newer devices feature a water bath-free environment, a reduced anesthesia requirement, improved imaging, functional uses in addition to lithotripsy, or combinations thereof. Shock wave generation by spark gap, electromagnetic, piezoelectric and microexplosive techniques are related to their peak energy, frequency, and total energy capabilities which impacts on both anesthesia needs and the length and number of treatment sessions required to pulverize calculi. A master table summarizes the types of SW energy, coupling, imaging systems, patient transport, functional features, cost, and treatment effectiveness of 12 worldwide lithotriptors in various stages of investigative and clinical trials as monitored by the Food and Drug Administration (FDA) of America.
Current EU-27 technical potential of organic waste streams for biogas and energy production.
Lorenz, Helge; Fischer, Peter; Schumacher, Britt; Adler, Philipp
2013-11-01
Anaerobic digestion of organic waste generated by households, businesses, agriculture, and industry is an important approach as method of waste treatment - especially with regard to its potential as an alternative energy source and its cost-effectiveness. Separate collection of biowaste from households or vegetal waste from public green spaces is already established in some EU-27 countries. The material recovery in composting plants is common for biowaste and vegetal waste. Brewery waste fractions generated by beer production are often used for animal feeding after a suitable preparation. Waste streams from paper industry generated by pulp and paper production such as black liquor or paper sludge are often highly contaminated with toxic substances. Recovery of chemicals and the use in thermal processes like incineration, pyrolysis, and gasification are typical utilization paths. The current utilization of organic waste from households and institutions (without agricultural waste) was investigated for EU-27 countries with Germany as an in-depth example. Besides of biowaste little is known about the suitability of waste streams from brewery and paper industry for anaerobic digestion. Therefore, an evaluation of the most important biogas process parameters for different substrates was carried out, in order to calculate the biogas utilization potential of these waste quantities. Furthermore, a calculation of biogas energy potentials was carried out for defined waste fractions which are most suitable for anaerobic digestion. Up to 1% of the primary energy demand can be covered by the calculated total biogas energy potential. By using a "best-practice-scenario" for separately collected biowaste, the coverage of primary energy demand may be increased above 2% for several countries. By using sector-specific waste streams, for example the German paper industry could cover up to 4.7% and the German brewery industry up to 71.2% of its total energy demand. Copyright © 2013 Elsevier Ltd. All rights reserved.
Wilburn, David R.
2011-01-01
The generation of electricity in the United States from wind-powered turbines is increasing. An understanding of the sources and abundance of raw materials required by the wind turbine industry and the many uses for these materials is necessary to assess the effect of this industry's growth on future demand for selected raw materials relative to the historical demand for these materials. The U.S. Geological Survey developed estimates of future requirements for raw (and some recycled) materials based on the assumption that wind energy will supply 20 percent of the electricity consumed in the United States by 2030. Economic, environmental, political, and technological considerations and trends reported for 2009 were used as a baseline. Estimates for the quantity of materials in typical "current generation" and "next generation" wind turbines were developed. In addition, estimates for the annual and total material requirements were developed based on the growth necessary for wind energy when converted in a wind powerplant to generate 20 percent of the U.S. supply of electricity by 2030. The results of the study suggest that achieving the market goal of 20 percent by 2030 would require an average annual consumption of about 6.8 million metric tons of concrete, 1.5 million metric tons of steel, 310,000 metric tons of cast iron, 40,000 metric tons of copper, and 380 metric tons of the rare-earth element neodymium. With the exception of neodymium, these material requirements represent less than 3 percent of the U.S. apparent consumption for 2008. Recycled material could supply about 3 percent of the total steel required for wind turbine production from 2010 through 2030, 4 percent of the aluminum required, and 3 percent of the copper required. The data suggest that, with the possible exception of rare-earth elements, there should not be a shortage of the principal materials required for electricity generation from wind energy. There may, however, be selective manufacturing shortages if the total demand for raw materials from all markets is greater than the available supply of these materials or the capacity of industry to manufacture components. Changing economic conditions could also affect the development schedule of anticipated capacity.
Multi-stage depressed collector for small orbit gyrotrons
Singh, Amarjit; Ives, R. Lawrence; Schumacher, Richard V.; Mizuhara, Yosuke M.
1998-01-01
A multi-stage depressed collector for receiving energy from a small orbit gyrating electron beam employs a plurality of electrodes at different potentials for sorting the individual electrons on the basis of their total energy level. Magnetic field generating coils, for producing magnetic fields and magnetic iron for magnetic field shaping produce adiabatic and controlled non-adiabatic transitions of the incident electron beam to further facilitate the sorting.
Multi-stage depressed collector for small orbit gyrotrons
Singh, A.; Ives, R.L.; Schumacher, R.V.; Mizuhara, Y.M.
1998-07-14
A multi-stage depressed collector for receiving energy from a small orbit gyrating electron beam employs a plurality of electrodes at different potentials for sorting the individual electrons on the basis of their total energy level. Magnetic field generating coils, for producing magnetic fields and magnetic iron for magnetic field shaping produce adiabatic and controlled non-adiabatic transitions of the incident electron beam to further facilitate the sorting. 9 figs.
Second law analysis of a conventional steam power plant
NASA Technical Reports Server (NTRS)
Liu, Geng; Turner, Robert H.; Cengel, Yunus A.
1993-01-01
A numerical investigation of exergy destroyed by operation of a conventional steam power plant is computed via an exergy cascade. An order of magnitude analysis shows that exergy destruction is dominated by combustion and heat transfer across temperature differences inside the boiler, and conversion of energy entering the turbine/generator sets from thermal to electrical. Combustion and heat transfer inside the boiler accounts for 53.83 percent of the total exergy destruction. Converting thermal energy into electrical energy is responsible for 41.34 percent of the total exergy destruction. Heat transfer across the condenser accounts for 2.89 percent of the total exergy destruction. Fluid flow with friction is responsible for 0.50 percent of the total exergy destruction. The boiler feed pump turbine accounts for 0.25 percent of the total exergy destruction. Fluid flow mixing is responsible for 0.23 percent of the total exergy destruction. Other equipment including gland steam condenser, drain cooler, deaerator and heat exchangers are, in the aggregate, responsible for less than one percent of the total exergy destruction. An energy analysis is also given for comparison of exergy cascade to energy cascade. Efficiencies based on both the first law and second law of thermodynamics are calculated for a number of components and for the plant. The results show that high first law efficiency does not mean high second law efficiency. Therefore, the second law analysis has been proven to be a more powerful tool in pinpointing real losses. The procedure used to determine total exergy destruction and second law efficiency can be used in a conceptual design and parametric study to evaluate the performance of other steam power plants and other thermal systems.
Practice of Meteorological Services in Turpan Solar Eco-City in China (Invited)
NASA Astrophysics Data System (ADS)
Shen, Y.; Chang, R.; He, X.; Jiang, Y.; Zhao, D.; Ma, J.
2013-12-01
Turpan Solar Eco-City is located in Gobi in Northwest China, which is one of the National New Energy Demonstration Urban. The city was planed and designed from October of 2008 and constructed from May of 2010, and the first phase of the project has been completed by October of 2013. Energy supply in Turpan Solar Eco-City is mainly from PV power, which is installed in all of the roof and the total capacity is 13.4MW. During the planning and designing of the city, and the running of the smart grid, meteorological services have played an important role. 1) Solar Energy Resource Assessment during Planning Phase. According to the observed data from meteorological stations in recent 30 years, solar energy resource was assessed and available PV power generation capacity was calculated. The results showed that PV power generation capacity is 1.3 times the power consumption, that is, solar energy resource in Turpan is rich. 2) Key Meteorological Parameters Determination for Architectural Design. A professional solar energy resource station was constructed and the observational items included Global Horizontal Irradiance, Inclined Total Solar Irradiance at 30 degree, Inclined Total Solar Irradiance at local latitude, and so on. According these measured data, the optical inclined angle for PV array was determined, that is, 30 degree. The results indicated that the annual irradiation on inclined plane with optimal angle is 1.4% higher than the inclined surface with latitude angle, and 23.16% higher than the horizontal plane. The diffuse ratio and annual variation of the solar elevation angle are two major factors that influence the irradiation on inclined plane. 3) Solar Energy Resource Forecast for Smart Grid. Weather Research Forecast (WRF) model was used to forecast the hourly solar radiation of future 72 hours and the measured irradiance data was used to forecast the minutely solar radiation of future 4 hours. The forecast results were submitted to smart grid and used to regulate the local grid and the city gird.
NASA Astrophysics Data System (ADS)
Briggs, C. K.; Borg, I. Y.
1982-10-01
Flow diagrams to describe the US energy situation are given. In 1981 the energy consumption was 73 quads (or 73 times 10 to the 15th power Btu). Use was down from 75 quads in 1980. Oil continues to dominate the picture as it comprises 45% of the total energy used. Net oil use (exclusive of oil purchased for the Strategic Petroleum Reserve and Exports) fell 8%; oil imports declined 14%. In contrast to oil, use of natural gas and coal remained at 1980 levels. Decreased use of residual oils, principally for electric power generating, account for much of the drop in oil use. Increased use of coal and nuclear energy for power generation almost compensated for the decrease in use of oil in that end use. Transmitted power remained at 1980 levels. The remainder of the drop in energy usage is attributed to price driven conservation, increased efficiencies in end use and the recession that prevailed during most of the year. The share of the energy drop attributable to the recession is estimated by various analysts to be on the order of 40 to 50%.
Rosa, A P; Conesa, J A; Fullana, A; Melo, G C B; Borges, J M; Chernicharo, C A L
2016-01-01
This work assessed the energy potential and alternative usages of biogas and sludge generated in upflow anaerobic sludge blanket reactors at the Laboreaux sewage treatment plant (STP), Brazil. Two scenarios were considered: (i) priority use of biogas for the thermal drying of dehydrated sludge and the use of the excess biogas for electricity generation in an ICE (internal combustion engine); and (ii) priority use of biogas for electricity generation and the use of the heat of the engine exhaust gases for the thermal drying of the sludge. Scenario 1 showed that the electricity generated is able to supply 22.2% of the STP power demand, but the thermal drying process enables a greater reduction or even elimination of the final volume of sludge to be disposed. In Scenario 2, the electricity generated is able to supply 57.6% of the STP power demand; however, the heat in the exhaust gases is not enough to dry the total amount of dehydrated sludge.
Johnson Space Center's Solar and Wind-Based Renewable Energy System
NASA Technical Reports Server (NTRS)
Vasquez, A.; Ewert, M.; Rowlands, J.; Post, K.
2009-01-01
The NASA Johnson Space Center (JSC) in Houston, Texas has a Sustainability Partnership team that seeks ways for earth-based sustainability practices to also benefit space exploration research. A renewable energy gathering system was installed in 2007 at the JSC Child Care Center (CCC) which also offers a potential test bed for space exploration power generation and remote monitoring and control concepts. The system comprises: 1) several different types of photovoltaic panels (29 kW), 2) two wind-turbines (3.6 kW total), and 3) one roof-mounted solar thermal water heater and tank. A tie to the JSC local electrical grid was provided to accommodate excess power. The total first year electrical energy production was 53 megawatt-hours. A web-based real-time metering system collects and reports system performance and weather data. Improvements in areas of the CCC that were detected during subsequent energy analyses and some concepts for future efforts are also presented.
Matching the laser generated p bunch into a crossbar-H drift tube linac
NASA Astrophysics Data System (ADS)
Almomani, A.; Droba, M.; Ratzinger, U.; Hofmann, I.
2012-05-01
Proton bunches with energies up to 30 MeV have been measured at the PHELIX laser. Because of the laser-plasma interactions at a power density of about 4×1019W/cm2, a total yield of 1.5×1013protons was produced. For the reference energy of 10 MeV, the yield within ±0.5MeV was exceeding 1010protons. The important topic for a further acceleration of the laser generated bunch is the matching into the acceptance of an rf accelerator stage. With respect to the high space charge forces and the transit energy range, only drift tube linacs seem adequate for this purpose. A crossbar H-type (CH) cavity was chosen as the linac structure. Optimum emittance values for the linac injection are compared with the available laser generated beam parameters. Options for beam matching into a CH structure by a pulsed magnetic solenoid and by using the simulation codes LASIN and LORASR are presented.
A recoil-proton spectrometer based on a p-i-n diode implementing pulse-shape discrimination.
Agosteo, S; D'Angelo, G; Fazzi, A; Foglio Para, A; Pola, A; Ventura, L; Zotto, P
2004-01-01
A recoil-proton spectrometer was created by coupling a p-i-n diode with a polyethylene converter. The maximum detectable energy, imposed by the thickness of the totally depleted layer, is approximately 6 MeV. The minimum detectable energy is limited by the contribution of secondary electrons generated by photons in the detector assembly. This limit is approximately 1.5 MeV at full-depletion voltage and was decreased using pulse-shape discrimination. The diode was set up in the 'reverse-injection' configuration (i.e. with the N+ layer adjacent to the converter). This configuration provides longer collection times for the electron-hole pairs generated by the recoil-protons. The pulse-shape discrimination was based on the zero-crossing time of bipolar signals from a (CR)2-(RC)2 filter. The detector was characterised using monoenergetic neutrons generated in the Van De Graaff CN accelerator at the INFN-Laboratori Nazionali di Legnaro. The energy limit for discrimination proved to be approximately 900 keV.
DOE Office of Scientific and Technical Information (OSTI.GOV)
ZOLOTOREV, M.; ZHOLENTS, A.; WANG, X.J.
2002-02-01
We are proposing an Atto-second electron beam generation and diagnostics experiment at the Brookhaven Accelerator Test facility (ATF) using 1 {micro}m Inverse Free Electron Laser (IFEL). The proposed experiment will be carried out by an BNL/LBNL collaboration, and it will be installed at the ATF beam line II. The proposed experiment will employ a one-meter long undulator with 1.8 cm period (VISA undulator). The electron beam energy will be 63 MeV with emittance less than 2 mm-mrad and energy spread less than 0.05%. The ATF photocathode injector driving laser will be used for energy modulation by Inverse Free Electron Lasermore » (IFEL). With 10 MW laser peak power, about 2% total energy modulation is expected. The energy modulated electron beam will be further bunched through either a drift space or a three magnet chicane into atto-second electron bunches. The attosecond electron beam bunches will be analyzed using the coherent transition radiation (CTR).« less
The CERN Large Hadron Collider as a tool to study high-energy density matter.
Tahir, N A; Kain, V; Schmidt, R; Shutov, A; Lomonosov, I V; Gryaznov, V; Piriz, A R; Temporal, M; Hoffmann, D H H; Fortov, V E
2005-04-08
The Large Hadron Collider (LHC) at CERN will generate two extremely powerful 7 TeV proton beams. Each beam will consist of 2808 bunches with an intensity per bunch of 1.15x10(11) protons so that the total number of protons in one beam will be about 3x10(14) and the total energy will be 362 MJ. Each bunch will have a duration of 0.5 ns and two successive bunches will be separated by 25 ns, while the power distribution in the radial direction will be Gaussian with a standard deviation, sigma=0.2 mm. The total duration of the beam will be about 89 mus. Using a 2D hydrodynamic code, we have carried out numerical simulations of the thermodynamic and hydrodynamic response of a solid copper target that is irradiated with one of the LHC beams. These calculations show that only the first few hundred proton bunches will deposit a high specific energy of 400 kJ/g that will induce exotic states of high energy density in matter.
Magnetic materials and devices for the 21st century: stronger, lighter, and more energy efficient.
Gutfleisch, Oliver; Willard, Matthew A; Brück, Ekkes; Chen, Christina H; Sankar, S G; Liu, J Ping
2011-02-15
A new energy paradigm, consisting of greater reliance on renewable energy sources and increased concern for energy efficiency in the total energy lifecycle, has accelerated research into energy-related technologies. Due to their ubiquity, magnetic materials play an important role in improving the efficiency and performance of devices in electric power generation, conditioning, conversion, transportation, and other energy-use sectors of the economy. This review focuses on the state-of-the-art hard and soft magnets and magnetocaloric materials, with an emphasis on their optimization for energy applications. Specifically, the impact of hard magnets on electric motor and transportation technologies, of soft magnetic materials on electricity generation and conversion technologies, and of magnetocaloric materials for refrigeration technologies, are discussed. The synthesis, characterization, and property evaluation of the materials, with an emphasis on structure-property relationships, are discussed in the context of their respective markets, as well as their potential impact on energy efficiency. Finally, considering future bottlenecks in raw materials, options for the recycling of rare-earth intermetallics for hard magnets will be discussed. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Duke, Dana Lynn
2015-11-12
This Ph.D. dissertation describes a measurement of the change in mass distributions and average total kinetic energy (TKE) release with increasing incident neutron energy for fission of 235U and 238U. Although fission was discovered over seventy-five years ago, open questions remain about the physics of the fission process. The energy of the incident neutron, En, changes the division of energy release in the resulting fission fragments, however, the details of energy partitioning remain ambiguous because the nucleus is a many-body quantum system. Creating a full theoretical model is difficult and experimental data to validate existing models are lacking. Additional fissionmore » measurements will lead to higher-quality models of the fission process, therefore improving applications such as the development of next-generation nuclear reactors and defense. This work also paves the way for precision experiments such as the Time Projection Chamber (TPC) for fission cross section measurements and the Spectrometer for Ion Determination in Fission (SPIDER) for precision mass yields.« less
Generation of dark hollow beam by use of phase-only filtering
NASA Astrophysics Data System (ADS)
Liu, Zhengjun; Dai, Jingmin; Zhao, Xiaoyi; Sun, Xiaogang; Liu, Shutian; Ashfaq Ahmad, Muhammad
2009-11-01
A simple but effective scheme to generate dark hollow beams is proposed by use of phase-only filtering and optical Fourier transform. A Gaussian beam of fundamental mode is modulated by a pre-designed phase mask, which is a piecewise modification of an axicon lens, and followed by a Fourier transform to generate an ideal dark hollow beam at the focal plane. This method has an advantage that the total energy of the beam is conserved under paraxial approximation. Numerical calculations are provided to show the validity of the proposed scheme.
NREL Triples Previous Estimates of U.S. Wind Power Potential (Fact Sheet)
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
The National Renewable Energy Laboratory (NREL) recently released new estimates of the U.S. potential for wind-generated electricity, using advanced wind mapping and validation techniques to triple previous estimates of the size of the nation's wind resources. The new study, conducted by NREL and AWS TruePower, finds that the contiguous 48 states have the potential to generate up to 37 million gigawatt-hours annually. In comparison, the total U.S. electricity generation from all sources was roughly 4 million gigawatt-hours in 2009.
Petersen, Abdul M; Haigh, Kate; Görgens, Johann F
2014-01-01
Flow sheet options for integrating ethanol production from spent sulfite liquor (SSL) into the acid-based sulfite pulping process at the Sappi Saiccor mill (Umkomaas, South Africa) were investigated, including options for generation of thermal and electrical energy from onsite bio-wastes, such as bark. Processes were simulated with Aspen Plus® for mass- and energy-balances, followed by an estimation of the economic viability and environmental impacts. Various concentration levels of the total dissolved solids in magnesium oxide-based SSL, which currently fuels a recovery boiler, prior to fermentation was considered, together with return of the fermentation residues (distillation bottoms) to the recovery boiler after ethanol separation. The generation of renewable thermal and electrical energy from onsite bio-wastes were also included in the energy balance of the combined pulping-ethanol process, in order to partially replace coal consumption. The bio-energy supplementations included the combustion of bark for heat and electricity generation and the bio-digestion of the calcium oxide SSL to produce methane as additional energy source. Ethanol production from SSL at the highest substrate concentration was the most economically feasible when coal was used for process energy. However this solution did not provide any savings in greenhouse gas (GHG) emissions for the concentration-fermentation-distillation process. Maximizing the use of renewable energy sources to partially replace coal consumption yielded a satisfactory economic performance, with a minimum ethanol selling price of 0.83 US$/l , and a drastic reduction in the overall greenhouse gas emissions for the entire facility. High substrate concentrations and conventional distillation should be used when considering integrating ethanol production at sulfite pulping mills. Bio-wastes generated onsite should be utilized at their maximum potential for energy generation in order to maximize the GHG emissions reduction.
Analysis and Application of Microgrids
NASA Astrophysics Data System (ADS)
Yue, Lu
New trends of generating electricity locally and utilizing non-conventional or renewable energy sources have attracted increasing interests due to the gradual depletion of conventional fossil fuel energy sources. The new type of power generation is called Distributed Generation (DG) and the energy sources utilized by Distributed Generation are termed Distributed Energy Sources (DERs). With DGs embedded in the distribution networks, they evolve from passive distribution networks to active distribution networks enabling bidirectional power flows in the networks. Further incorporating flexible and intelligent controllers and employing future technologies, active distribution networks will turn to a Microgrid. A Microgrid is a small-scale, low voltage Combined with Heat and Power (CHP) supply network designed to supply electrical and heat loads for a small community. To further implement Microgrids, a sophisticated Microgrid Management System must be integrated. However, due to the fact that a Microgrid has multiple DERs integrated and is likely to be deregulated, the ability to perform real-time OPF and economic dispatch with fast speed advanced communication network is necessary. In this thesis, first, problems such as, power system modelling, power flow solving and power system optimization, are studied. Then, Distributed Generation and Microgrid are studied and reviewed, including a comprehensive review over current distributed generation technologies and Microgrid Management Systems, etc. Finally, a computer-based AC optimization method which minimizes the total transmission loss and generation cost of a Microgrid is proposed and a wireless communication scheme based on synchronized Code Division Multiple Access (sCDMA) is proposed. The algorithm is tested with a 6-bus power system and a 9-bus power system.
enoLOGOS: a versatile web tool for energy normalized sequence logos
Workman, Christopher T.; Yin, Yutong; Corcoran, David L.; Ideker, Trey; Stormo, Gary D.; Benos, Panayiotis V.
2005-01-01
enoLOGOS is a web-based tool that generates sequence logos from various input sources. Sequence logos have become a popular way to graphically represent DNA and amino acid sequence patterns from a set of aligned sequences. Each position of the alignment is represented by a column of stacked symbols with its total height reflecting the information content in this position. Currently, the available web servers are able to create logo images from a set of aligned sequences, but none of them generates weighted sequence logos directly from energy measurements or other sources. With the advent of high-throughput technologies for estimating the contact energy of different DNA sequences, tools that can create logos directly from binding affinity data are useful to researchers. enoLOGOS generates sequence logos from a variety of input data, including energy measurements, probability matrices, alignment matrices, count matrices and aligned sequences. Furthermore, enoLOGOS can represent the mutual information of different positions of the consensus sequence, a unique feature of this tool. Another web interface for our software, C2H2-enoLOGOS, generates logos for the DNA-binding preferences of the C2H2 zinc-finger transcription factor family members. enoLOGOS and C2H2-enoLOGOS are accessible over the web at . PMID:15980495
Holloran-Schwartz, M Brigid; Gavard, Jeffrey A; Martin, Jared C; Blaskiewicz, Robert J; Yeung, Patrick P
2016-01-01
To compare the intraoperative direct costs of a single-use energy device with reusable energy devices during laparoscopic hysterectomy. A randomized controlled trial (Canadian Task Force Classification I). An academic hospital. Forty-six women who underwent laparoscopic hysterectomy from March 2013 to September 2013. Each patient served as her own control. One side of the uterine attachments was desiccated and transected with the single-use device (Ligasure 5-mm Blunt Tip LF1537 with the Force Triad generator). The other side was desiccated and transected with reusable bipolar forceps (RoBi 5 mm), and transected with monopolar scissors using the same Covidien Force Triad generator. The instrument approach used was randomized to the attending physician who was always on the patient's left side. Resident physicians always operated on the patient's right side and used the converse instruments of the attending physician. Start time was recorded at the utero-ovarian pedicle and end time was recorded after transection of the uterine artery on the same side. Costs included the single-use device; amortized costs of the generator, reusable instruments, and cords; cleaning and packaging of reusable instruments; and disposal of the single-use device. Operating room time was $94.14/min. We estimated that our single use-device cost $630.14 and had a total time savings of 6.7 min per case, or 3.35 min per side, which could justify the expense of the device. The single-use energy device had significant median time savings (-4.7 min per side, p < .001) and total intraoperative direct cost savings ($254.16 per case). A single-use energy device that both desiccates and cuts significantly reduced operating room time to justify its own cost, and it also reduced total intraoperative direct costs during laparoscopic hysterectomy in our institution. Operating room cost per minute varies between institutions and must be considered before generalizing our results. Copyright © 2016 AAGL. Published by Elsevier Inc. All rights reserved.
Park, Beomguk; Cho, Eunju; Son, Younggyu; Khim, Jeehyeong
2014-11-01
Sonophotolytic degradation of THMs mixture with different electrical energy ratio was carried out for efficient design of process. The total consumed electrical energy was fixed around 50W, and five different energy conditions were applied. The maximum degradation rate showed in conditions of US:UV=1:3 and US:UV=0:4. This is because the photolytic degradation of bromate compounds is dominant degradation mechanism for THMs removal. However, the fastest degradation of total organic carbon was observed in a condition of US:UV=1:3. Because hydrogen peroxide generated by sonication was effectively dissociated to hydroxyl radicals by ultraviolet, the concentration of hydroxyl radical was maintained high. This mechanism provided additional degradation of organics. This result was supported by comparison between the concentration of hydrogen peroxide sole and combined process. Consequently, the optimal energy ratio was US:UV=1:3 for degradation of THMs in sonophotolytic process. Copyright © 2014 Elsevier Ltd. All rights reserved.
NASA Technical Reports Server (NTRS)
Tschunko, H. F. A.
1983-01-01
Reference is made to a study by Tschunko (1979) in which it was discussed how apodization modifies the modulation transfer function for various central obstruction ratios. It is shown here how apodization, together with the central obstruction ratio, modifies the point spread function, which is the basic element for the comparison of imaging performance and for the derivation of energy integrals and other functions. At high apodization levels and lower central obstruction (less than 0.1), new extended radial zones are formed in the outer part of the central ring groups. These transmutation of the image functions are of more than theoretical interest, especially if the irradiance levels in the outer ring zones are to be compared to the background irradiance levels. Attention is then given to the energy distribution in point images generated by annular apertures apodized by various transmission functions. The total energy functions are derived; partial energy integrals are determined; and background irradiance functions are discussed.
Boosting CSP Production with Thermal Energy Storage
DOE Office of Scientific and Technical Information (OSTI.GOV)
Denholm, P.; Mehos, M.
2012-06-01
Combining concentrating solar power (CSP) with thermal energy storage shows promise for increasing grid flexibility by providing firm system capacity with a high ramp rate and acceptable part-load operation. When backed by energy storage capability, CSP can supplement photovoltaics by adding generation from solar resources during periods of low solar insolation. The falling cost of solar photovoltaic (PV) - generated electricity has led to a rapid increase in the deployment of PV and projections that PV could play a significant role in the future U.S. electric sector. The solar resource itself is virtually unlimited; however, the actual contribution of PVmore » electricity is limited by several factors related to the current grid. The first is the limited coincidence between the solar resource and normal electricity demand patterns. The second is the limited flexibility of conventional generators to accommodate this highly variable generation resource. At high penetration of solar generation, increased grid flexibility will be needed to fully utilize the variable and uncertain output from PV generation and to shift energy production to periods of high demand or reduced solar output. Energy storage is one way to increase grid flexibility, and many storage options are available or under development. In this article, however, we consider a technology already beginning to be used at scale - thermal energy storage (TES) deployed with concentrating solar power (CSP). PV and CSP are both deployable in areas of high direct normal irradiance such as the U.S. Southwest. The role of these two technologies is dependent on their costs and relative value, including how their value to the grid changes as a function of what percentage of total generation they contribute to the grid, and how they may actually work together to increase overall usefulness of the solar resource. Both PV and CSP use solar energy to generate electricity. A key difference is the ability of CSP to utilize high-efficiency TES, which turns CSP into a partially dispatchable resource. The addition of TES produces additional value by shifting the delivery of solar energy to periods of peak demand, providing firm capacity and ancillary services, and reducing integration challenges. Given the dispatchability of CSP enabled by TES, it is possible that PV and CSP are at least partially complementary. The dispatchability of CSP with TES can enable higher overall penetration of the grid by solar energy by providing solar-generated electricity during periods of cloudy weather or at night, when PV-generated power is unavailable. Such systems also have the potential to improve grid flexibility, thereby enabling greater penetration of PV energy (and other variable generation sources such as wind) than if PV were deployed without CSP.« less
NASA Astrophysics Data System (ADS)
Baksht, E. Kh; Panchenko, Aleksei N.; Tarasenko, Viktor F.
2000-06-01
An efficient electric-discharge XeCl laser is developed, which is pumped by a self-sustained discharge with a prepulse formed by a generator with an inductive energy storage device and a semiconductor current interrupter on a basis of semiconductor opening switch (SOS) diodes. An output energy up to 800 mJ, a pulse length up to 450 ns, and a total laser efficiency of 2.2% were attained by using spark UV preionisation.
NASA Astrophysics Data System (ADS)
Yin, Libao; Liao, Yanfen; Zhou, Lianjie; Wang, Zhao; Ma, Xiaoqian
2017-05-01
The life cycle assessment and environmental impacts of a 1000MW coal-fired power plant were carried out in this paper. The results showed that the operation energy consumption and pollutant emission of the power plant are the highest in all sub-process, which accounts for 93.93% of the total energy consumption and 92.20% of the total emission. Compared to other pollutant emissions from the coal-fired power plant, CO2 reached up to 99.28%. Therefore, the control of CO2 emission from the coal-fired power plants was very important. Based on the BP neural network, the amount of CO2 emission from the generation side of coal-fired power plants was calculated via carbon balance method. The results showed that unit capacity, coal quality and unit operation load had great influence on the CO2 emission from coal-fired power plants in Guangdong Province. The use of high volatile and high heat value of coal also can reduce the CO2 emissions. What’s more, under higher operation load condition, the CO2 emissions of 1 kWh electric energy was less.
Method for Evaluating Energy Use of Dishwashers, Clothes Washers, and Clothes Dryers: Preprint
DOE Office of Scientific and Technical Information (OSTI.GOV)
Eastment, M.; Hendron, R.
Building America teams are researching opportunities to improve energy efficiency for some of the more challenging end-uses, such as lighting (both fixed and occupant-provided), appliances (clothes washer, dishwasher, clothes dryer, refrigerator, and range), and miscellaneous electric loads, which are all heavily dependent on occupant behavior and product choices. These end-uses have grown to be a much more significant fraction of total household energy use (as much as 50% for very efficient homes) as energy efficient homes have become more commonplace through programs such as ENERGY STAR and Building America. As modern appliances become more sophisticated the residential energy analyst ismore » faced with a daunting task in trying to calculate the energy savings of high efficiency appliances. Unfortunately, most whole-building simulation tools do not allow the input of detailed appliance specifications. Using DOE test procedures the method outlined in this paper presents a reasonable way to generate inputs for whole-building energy-simulation tools. The information necessary to generate these inputs is available on Energy-Guide labels, the ENERGY-STAR website, California Energy Commission's Appliance website and manufacturer's literature. Building America has developed a standard method for analyzing the effect of high efficiency appliances on whole-building energy consumption when compared to the Building America's Research Benchmark building.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
NONE
Nuclear power has safely, reliably, and economically contributed almost 20% of electrical generation in the United States over the past two decades. It remains the single largest contributor (more than 60%) of non-greenhouse-gas-emitting electric power generation in the United States. Domestic demand for electrical energy is expected to grow by about 24% from 2013 to 2040 . At the same time, most of the currently operating nuclear power plants will begin reaching the end of their initial 20-year extension to their original 40-year operating license, for a total of 60 years of operation (the oldest commercial plants in the Unitedmore » States reached their 40th anniversary in 2009). Figure E-1 shows projected nuclear energy contribution to the domestic generating capacity for 40- and 60-year license periods. If current operating nuclear power plants do not operate beyond 60 years (and new nuclear plants are not built quickly enough to replace them), the total fraction of generated electrical energy from nuclear power will rapidly decline. That decline will be accelerated if plants are shut down before 60 years of operation. Decisions on extended operation ultimately rely on economic factors; however, economics can often be improved through technical advancements. The U.S. Department of Energy Office of Nuclear Energy's 2010 Research and Development Roadmap (2010 Nuclear Energy Roadmap) organizes its activities around four objectives that ensure nuclear energy remains a compelling and viable energy option for the United States. The four objectives are as follows: 1. Develop technologies and other solutions that can improve the reliability, sustain the safety, and extend the life of the current reactors; 2. Develop improvements in the affordability of new reactors to enable nuclear energy to help meet the Administration's energy security and climate change goals; 3. Develop sustainable nuclear fuel cycles; and 4. Understand and minimize the risks of nuclear proliferation and terrorism. The Light Water Reactor Sustainability (LWRS) Program is the primary programmatic activity that addresses Objective 1. This document summarizes the LWRS Program's plans. For the LWRS Program, sustainability is defined as the ability to maintain safe and economic operation of the existing fleet of nuclear power plants for a longer-than-initially-licensed lifetime. It has two facets with respect to long-term operations: (1) manage the aging of plant systems, structures, and components so that nuclear power plant lifetimes can be extended and the plants can continue to operate safely, efficiently, and economically; and (2) provide science-based solutions to the industry to implement technology to exceed the performance of the current labor-intensive business model.« less
Chondrocytes treated with different shock wave devices.
Notarnicola, Angela; Iannone, Florenzo; Maccagnano, Giuseppe; Lacarpia, Nuniza; Bizzoca, Dorotea; Moretti, Biagio
2017-01-01
Shock wave treatment is used for several orthopedic diseases and there are different devices available. Until now, there have been no experimental studies on the effects of these different generators. We carried out an experimental study to compare the effects of three focused generators (electro-magnetic, piezoelectric and electro-hydraulic) as well as a radial generator on healthy and osteoarthritis chondrocytes. By the analysis of our results, we may exclude significant differences between the different generators, even though there is a greater action specificity for electro-magnetic and piezoelectric generators. The smaller size of the focus of the latter two generators guarantees a greater concentration of energy in the target. The biological effect of the increase of IL-10 and reduction of both N-Cadherin and B-Catenin in chondrocytes in healthy subjects and those affected by osteoarthritis confirms the therapeutic potential of ESWT in cartilage diseases, such as osteoarthritis. In clinical practice it is important to introduce the parameter of total energy. This allows us to standardize the treatment and to manage the variability related to the different types of device and size of the focus. IIb.
Traveling-wave induction launchers
NASA Technical Reports Server (NTRS)
Elliott, David G.
1989-01-01
An analysis of traveling-wave induction launchers shows that induction is a feasible method of producing armature current and that efficient accelerators can be built without sliding contacts or arcs. In a traveling-wave induction launcher the armature current is induced by a slip speed between the armature and a traveling magnetic field. At 9 m/s slip speed a 9 kg projectile with an aluminum armature weighing 25 percent of the total mass can be accelerated to 3000 m/s in a 5 m-long barrel with a total ohmic loss in the barrel coils and armature of 4 percent of the launch kinetic energy and with an average armature temperature rise of 220 deg C, but a peak excitation frequency of 8600 Hz is required. With a 2 kg launch mass the ohmic loss is 7 percent. A launcher system optimized for rotating generators would have a peak frequency of 4850 Hz; with an aluminum armature weighing 33 percent of the launch mass and a slip speed of 30 m/s the total ohmic loss in the generators, cables, and accelerator would be 43 percent of the launch kinetic energy, and the average armature temperature rise would be 510 deg C.
Measurements of the total cross section of natBe with thermal neutrons from a photo-neutron source
NASA Astrophysics Data System (ADS)
Liu, L. X.; Wang, H. W.; Ma, Y. G.; Cao, X. G.; Cai, X. Z.; Chen, J. G.; Zhang, G. L.; Han, J. L.; Zhang, G. Q.; Hu, J. F.; Wang, X. H.; Li, W. J.; Yan, Z.; Fu, H. J.
2017-11-01
The total neutron cross sections of natural beryllium in the neutron energy region of 0.007 to 0.1 eV were measured by using a time-of-flight (TOF) technique at the Shanghai Institute of Applied Physics (SINAP). The low energy neutrons were obtained by moderating the high energy neutrons from a pulsed photo-neutron source generated from a 16 MeV electron linac. The time dependent neutron background component was determined by employing the 12.8 cm boron-loaded polyethylene (PEB) (5% w.t.) to block neutron TOF path and using the Monte Carlo simulation methods. The present data was compared with the fold Harvey data with the response function of the photo-neutron source (PNS, phase-1). The present measurement of total cross section of natBe for thermal neutrons based on PNS has been developed for the acquisition of nuclear data needed for the Thorium Molten Salt Reactor (TMSR).
Integrally geared and integrated turbine generator energy recovery for high pressure natural gas
DOE Office of Scientific and Technical Information (OSTI.GOV)
Agahi, R.R.; Ershaghi, B.; Moser, H.
1995-12-31
Recovery of pressure let-down energy dates back to the early 1980`s. Several installations have proven the feasibility and attractive pay back of using turbine generator system in lieu of throttling valves. These installations, on average, are saving up to 200,000 barrels of fuel oil per year. Since the first installation, many improvements have been implemented in turboexpander packages and the associated control systems. Based on site requirements, two alternate designs may be introduced. One is a totally encapsulated integral turboexpander generator unit. The other is an integrally geared turboexpander. Both alternatives have the flexibility necessary to cope with a widemore » range of inlet gas conditions while maintaining required outlet gas conditions. These installations are environmentally friendly (no hazardous gas leakage) and operate within an acceptable noise level.« less
Relativistic differential-difference momentum operators and noncommutative differential calculus
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mir-Kasimov, R. M., E-mail: mirkr@theor.jinr.ru
2013-09-15
The relativistic kinetic momentum operators are introduced in the framework of the Quantum Mechanics (QM) in the Relativistic Configuration Space (RCS). These operators correspond to the half of the non-Euclidean distance in the Lobachevsky momentum space. In terms of kinetic momentum operators the relativistic kinetic energy is separated as the independent term of the total Hamiltonian. This relativistic kinetic energy term is not distinguishing in form from its nonrelativistic counterpart. The role of the plane wave (wave function of the motion with definite value of momentum and energy) plays the generating function for the matrix elements of the unitary irrepsmore » of Lorentz group (generalized Jacobi polynomials). The kinetic momentum operators are the interior derivatives in the framework of the noncommutative differential calculus over the commutative algebra generated by the coordinate functions over the RCS.« less
The Energy Spectra of Heavy Nuclei Measured by the ATIC Experiment
NASA Technical Reports Server (NTRS)
Panov, A. D.; Adams, J. H.; Ahn, H. S.; Bashindzhagyan, G. L.; Batkov, K. E.; Chang, J.; Christl, M.; Fazley, A. R.; Ganel, O.; Gunasingha, R. M.
2004-01-01
ATIC (Advanced Thin Ionization Calorimeter) is a balloon-borne experiment to measure the spectra and composition of primary cosmic rays in the region of total energy from 100 GeV to near 100 TeV for Z from 1 to 26. ATIC consists of a pixelated silicon matrix detector to measure charge plus a fully active BGO calorimeter, to measure energy, located below a carbon target interleaved with three layers of scintillator hodoscope. The ATIC instrument had a second (scientific) flight from McMurdo, Antarctica from 12/29/02 to 1/18/03, yielding 20 days of good data. The GEANT 3.21 Monte Carlo code with the QGSM event generator and the FLUKA code with the DPMJET-II event generator were used to convert energy deposition measurements to primary energy. We present the preliminary energy spectra for the abundant elements C, O, Ne, Mg, Si and Fe and compare them with the results of the first (test) flight of ATIC in 2000-01 and with results from the HEAO-3 and CRN experiments.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chen, Yixing; Hong, Tianzhen; Piette, Mary Ann
Buildings in cities consume 30–70% of total primary energy, and improving building energy efficiency is one of the key strategies towards sustainable urbanization. Urban building energy models (UBEM) can support city managers to evaluate and prioritize energy conservation measures (ECMs) for investment and the design of incentive and rebate programs. This paper presents the retrofit analysis feature of City Building Energy Saver (CityBES) to automatically generate and simulate UBEM using EnergyPlus based on cities’ building datasets and user-selected ECMs. CityBES is a new open web-based tool to support city-scale building energy efficiency strategic plans and programs. The technical details ofmore » using CityBES for UBEM generation and simulation are introduced, including the workflow, key assumptions, and major databases. Also presented is a case study that analyzes the potential retrofit energy use and energy cost savings of five individual ECMs and two measure packages for 940 office and retail buildings in six city districts in northeast San Francisco, United States. The results show that: (1) all five measures together can save 23–38% of site energy per building; (2) replacing lighting with light-emitting diode lamps and adding air economizers to existing heating, ventilation and air-conditioning (HVAC) systems are most cost-effective with an average payback of 2.0 and 4.3 years, respectively; and (3) it is not economical to upgrade HVAC systems or replace windows in San Francisco due to the city's mild climate and minimal cooling and heating loads. Furthermore, the CityBES retrofit analysis feature does not require users to have deep knowledge of building systems or technologies for the generation and simulation of building energy models, which helps overcome major technical barriers for city managers and their consultants to adopt UBEM.« less
Chen, Yixing; Hong, Tianzhen; Piette, Mary Ann
2017-08-07
Buildings in cities consume 30–70% of total primary energy, and improving building energy efficiency is one of the key strategies towards sustainable urbanization. Urban building energy models (UBEM) can support city managers to evaluate and prioritize energy conservation measures (ECMs) for investment and the design of incentive and rebate programs. This paper presents the retrofit analysis feature of City Building Energy Saver (CityBES) to automatically generate and simulate UBEM using EnergyPlus based on cities’ building datasets and user-selected ECMs. CityBES is a new open web-based tool to support city-scale building energy efficiency strategic plans and programs. The technical details ofmore » using CityBES for UBEM generation and simulation are introduced, including the workflow, key assumptions, and major databases. Also presented is a case study that analyzes the potential retrofit energy use and energy cost savings of five individual ECMs and two measure packages for 940 office and retail buildings in six city districts in northeast San Francisco, United States. The results show that: (1) all five measures together can save 23–38% of site energy per building; (2) replacing lighting with light-emitting diode lamps and adding air economizers to existing heating, ventilation and air-conditioning (HVAC) systems are most cost-effective with an average payback of 2.0 and 4.3 years, respectively; and (3) it is not economical to upgrade HVAC systems or replace windows in San Francisco due to the city's mild climate and minimal cooling and heating loads. Furthermore, the CityBES retrofit analysis feature does not require users to have deep knowledge of building systems or technologies for the generation and simulation of building energy models, which helps overcome major technical barriers for city managers and their consultants to adopt UBEM.« less
Implementation of optimum solar electricity generating system
DOE Office of Scientific and Technical Information (OSTI.GOV)
Singh, Balbir Singh Mahinder, E-mail: balbir@petronas.com.my; Karim, Samsul Ariffin A., E-mail: samsul-ariffin@petronas.com.my; Sivapalan, Subarna, E-mail: subarna-sivapalan@petronas.com.my
2014-10-24
Under the 10{sup th} Malaysian Plan, the government is expecting the renewable energy to contribute approximately 5.5% to the total electricity generation by the year 2015, which amounts to 98MW. One of the initiatives to ensure that the target is achievable was to establish the Sustainable Energy Development Authority of Malaysia. SEDA is given the authority to administer and manage the implementation of the feed-in tariff (FiT) mechanism which is mandated under the Renewable Energy Act 2011. The move to establish SEDA is commendable and the FiT seems to be attractive but there is a need to create awareness onmore » the implementation of the solar electricity generating system (SEGS). In Malaysia, harnessing technologies related to solar energy resources have great potential for implementation. However, the main issue that plagues the implementation of SEGS is the intermittent nature of this source of energy. The availability of sunlight is during the day time, and there is a need for electrical energy storage system, so that there is electricity available during the night time as well. The meteorological condition such as clouds, haze and pollution affects the SEGS as well. The PV based SEGS is seems to be promising electricity generating system that can contribute towards achieving the 5.5% target and will be able to minimize the negative effects of utilizing fossil fuels for electricity generation on the environment. Malaysia is committed to Kyoto Protocol, which emphasizes on fighting global warming by achieving stabilization of greenhouse gas concentrations in the atmosphere at a level that would prevent dangerous anthropogenic interference with the climate system. In this paper, the technical aspects of the implementation of optimum SEGS is discussed, especially pertaining to the positioning of the PV panels.« less
Implementation of optimum solar electricity generating system
NASA Astrophysics Data System (ADS)
Singh, Balbir Singh Mahinder; Sivapalan, Subarna; Najib, Nurul Syafiqah Mohd; Menon, Pradeep; Karim, Samsul Ariffin A.
2014-10-01
Under the 10th Malaysian Plan, the government is expecting the renewable energy to contribute approximately 5.5% to the total electricity generation by the year 2015, which amounts to 98MW. One of the initiatives to ensure that the target is achievable was to establish the Sustainable Energy Development Authority of Malaysia. SEDA is given the authority to administer and manage the implementation of the feed-in tariff (FiT) mechanism which is mandated under the Renewable Energy Act 2011. The move to establish SEDA is commendable and the FiT seems to be attractive but there is a need to create awareness on the implementation of the solar electricity generating system (SEGS). In Malaysia, harnessing technologies related to solar energy resources have great potential for implementation. However, the main issue that plagues the implementation of SEGS is the intermittent nature of this source of energy. The availability of sunlight is during the day time, and there is a need for electrical energy storage system, so that there is electricity available during the night time as well. The meteorological condition such as clouds, haze and pollution affects the SEGS as well. The PV based SEGS is seems to be promising electricity generating system that can contribute towards achieving the 5.5% target and will be able to minimize the negative effects of utilizing fossil fuels for electricity generation on the environment. Malaysia is committed to Kyoto Protocol, which emphasizes on fighting global warming by achieving stabilization of greenhouse gas concentrations in the atmosphere at a level that would prevent dangerous anthropogenic interference with the climate system. In this paper, the technical aspects of the implementation of optimum SEGS is discussed, especially pertaining to the positioning of the PV panels.
NASA Astrophysics Data System (ADS)
Zainudin, W. N. R. A.; Ishak, W. W. M.
2017-09-01
In 2009, government of Malaysia has announced a National Renewable Energy Policy and Action Plan as part of their commitment to accelerate the growth in renewable energies (RE). However, an adoption of RE as a main source of energy is still at an early stage due to lack of public awareness and acceptance on RE. Up to date, there are insufficient studies done on the reasons behind this lack of awareness and acceptance. Therefore, this paper is interested to investigate the public acceptance towards development of RE by measuring their willingness to pay slightly more for energy generated from RE sources, denote as willingness level and whether the importance for the electricity to be supplied at absolute lowest possible cost regardless of source and environmental impact, denote as importance level and other socio-economic factors could improve their willingness level. Both qualitative and quantitative research methods are used to achieve the research objectives. A total of 164 respondents from local universities in Malaysia participated in a survey to collect this relevant information. Using Ordered Probit model, the study shows that among the relevant socio-economic factors, age seems to be an important factor to influence the willingness level of the respondents. This paper concludes that younger generation are more willing to pay slightly more for energy generated from RE sources as compared to older generation. One of the possible reason may due to better information access by the younger generation on the RE issues and its positive implication to the world. Finding from this paper is useful to help policy maker in designing RE advocacy programs that would be able to secure public participation. These efforts are important to ensure future success of the RE policy.
NASA Astrophysics Data System (ADS)
Romanova, Vanya; Hense, Andreas
2017-08-01
In our study we use the anomaly transform, a special case of ensemble transform method, in which a selected set of initial oceanic anomalies in space, time and variables are defined and orthogonalized. The resulting orthogonal perturbation patterns are designed such that they pick up typical balanced anomaly structures in space and time and between variables. The metric used to set up the eigen problem is taken either as the weighted total energy with its zonal, meridional kinetic and available potential energy terms having equal contributions, or the weighted ocean heat content in which a disturbance is applied only to the initial temperature fields. The choices of a reference state for defining the initial anomalies are such that either perturbations on seasonal timescales and or on interannual timescales are constructed. These project a-priori only the slow modes of the ocean physical processes, such that the disturbances grow mainly in the Western Boundary Currents, in the Antarctic Circumpolar Current and the El Nino Southern Oscillation regions. An additional set of initial conditions is designed to fit in a least square sense data from global ocean reanalysis. Applying the AT produced sets of disturbances to oceanic initial conditions initialized by observations of the MPIOM-ESM coupled model on T63L47/GR15 resolution, four ensemble and one hind-cast experiments were performed. The weighted total energy norm is used to monitor the amplitudes and rates of the fastest growing error modes. The results showed minor dependence of the instabilities or error growth on the selected metric but considerable change due to the magnitude of the scaling amplitudes of the perturbation patterns. In contrast to similar atmospheric applications, we find an energy conversion from kinetic to available potential energy, which suggests a different source of uncertainty generation in the ocean than in the atmosphere mainly associated with changes in the density field.
Constraining the Energetics of Explosive Lava-Water Interactions
NASA Astrophysics Data System (ADS)
Fitch, E. P.; Fagents, S. A.
2017-12-01
During volcanic eruptions, water, such as groundwater or melted ice or snow, may interact with magma within the conduit during eruption, generating explosions when the heat of the magma causes the water to rapidly turn to steam and expand, resulting in what we call a "phreatomagmatic" eruption. In 2010, the eruption of Eyjafjallajökull volcano in Iceland produced a plume of fine ash, through the interaction between magma and glacial melt water, which resulted in the closure of substantial airspace, ultimately costing a total of almost 5 billion dollars. Although an important area of study, it is difficult to quantify the effect of eternal water on eruption intensity when the gas inside of magma is also expanding and fragmenting the magma. In an attempt to understand the energetics of magma-water interactions, small-scale laboratory experiments have been performed. Explosion energy is found to depend mostly on kinetic energy, which is proportional to dispersal distance, and fragmentation energy, which is proportional to the mean grain size of the ejecta, and the mass percent of ash-sized grains. It is thought that in order to generate heat transfer rates sufficiently rapid to cause explosive detonation, the source melt must be finely fragmented, producing ash-sized grains. Those grains undergo brittle fragmentation due to rapid cooling and weak shock waves generated by the vaporization of superheated water. We take the novel approach of studying explosive interactions between lava and water to obtain additional explosion energy constraints. We identified and analyzed numerous beds of lava-water explosion ejecta of varying explosion energy, and we analyzed the ash-sized grains of these beds in detail. We verified that the mass of ash-sized grains increases with increasing explosion energy, and can form at the interface between lava and water. We found that brittle fragmentation occurs to a greater degree as grain size decreases and that the ash of highly-energetic explosions undergoes the most brittle fragmentation. Therefore, our next steps will be to use these results to constrain the fragmentation and kinetic energy, in order to calculate the total energy and heat-transfer rate of lava-water explosions as important analogs for phreatomagmatic eruptions.
ELECTRICITY GENERATION FROM ANAEROBIC WASTEWATER TREATMENT IN MICROBIAL FUEL CELLS (MFCS) - PHASE I
Municipal wastewater treatment plants represent a huge energy ‘sink’ in the United States. Estimates are that these plants consume up to 3 percent of the total amount of power consumed annually. Ironically, the wastewater is concentrated with materials (carbohydrates) which ...
DOE Office of Scientific and Technical Information (OSTI.GOV)
Yeh, G.P.; /Fermilab
Studies of requirements and specifications of crystals are necessary to develop a new generation of crystals for dual readout crystal hadron or total absorption calorimeter. This is a short and basic study of the characteristics and hadron energy measurement of PbWO4 and BGO crystals for scintillation and Cerenkov Dual Readout hadron calorimeter.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mohanpurkar, Manish; Luo, Yusheng; Hovsapian, Rob
Electricity generated by Hydropower Plants (HPPs) contributes a considerable portion of bulk electricity generation and delivers it with a low carbon footprint. In fact, HPP electricity generation provides the largest share from renewable energy resources, which includes solar and wind energy. The increasing penetration of wind and solar penetration leads to a lowered inertia in the grid and hence poses stability challenges. In recent years, breakthrough in energy storage technologies have demonstrated the economic and technical feasibility of extensive deployments in power grids. Multiple ROR HPPs if integrated with scalable, multi time-step energy storage so that the total output canmore » be controlled. Although, the size of a single energy storage is far smaller than that of a typical reservoir, cohesively managing multiple sets of energy storage distributed in different locations is proposed. The ratings of storages and multiple ROR HPPs approximately equals the rating of a large, conventional HPP. The challenges associated with the system architecture and operation are described. Energy storage technologies such as supercapacitors, flywheels, batteries etc. can function as a dispatchable synthetic reservoir with a scalable size of energy storage will be integrated. Supercapacitors, flywheels, and battery are chosen to provide fast, medium, and slow responses to support grid requirements. Various dynamic and transient power grid conditions are simulated and performances of integrated ROR HPPs with energy storage is provided. The end goal of this research is to investigate the inertial equivalence of a large, conventional HPP with a unique set of multiple ROR HPPs and optimally rated energy storage systems.« less
NASA Astrophysics Data System (ADS)
Sundaramoorthy, Kumaravel
2017-02-01
The hybrid energy systems (HESs) based electricity generation system has become a more attractive solution for rural electrification nowadays. Economically feasible and technically reliable HESs are solidly based on an optimisation stage. This article discusses about the optimal unit sizing model with the objective function to minimise the total cost of the HES. Three typical rural sites from southern part of India have been selected for the application of the developed optimisation methodology. Feasibility studies and sensitivity analysis on the optimal HES are discussed elaborately in this article. A comparison has been carried out with the Hybrid Optimization Model for Electric Renewable optimisation model for three sites. The optimal HES is found with less total net present rate and rate of energy compared with the existing method
The effect of low velocity impact in the strength characteristics of composite materials laminates
NASA Technical Reports Server (NTRS)
Liebowitz, H.
1983-01-01
The nonlinear vibration response of a double cantilevered beam subjected to pulse loading over a central sector is studied. The initial response is generated in detail to ascertain the energetics of the response. The total energy is used as a gauge of the stability and accuracy of the solution. It is shown that to obtain accurate and stable initial solutions an extremely high spatial and time resolution is required. This requirement was only evident through an examination of the energy of the system. It is proposed, therefore, to use the total energy of the system as a necessary stability and accuracy criterion for the nonlinear response of conservative systems. The results also demonstrate that even for moderate nonlinearities, the effects of membrane forces have a significant influence on the system.
DFTB3: Extension of the self-consistent-charge density-functional tight-binding method (SCC-DFTB).
Gaus, Michael; Cui, Qiang; Elstner, Marcus
2012-04-10
The self-consistent-charge density-functional tight-binding method (SCC-DFTB) is an approximate quantum chemical method derived from density functional theory (DFT) based on a second-order expansion of the DFT total energy around a reference density. In the present study we combine earlier extensions and improve them consistently with, first, an improved Coulomb interaction between atomic partial charges, and second, the complete third-order expansion of the DFT total energy. These modifications lead us to the next generation of the DFTB methodology called DFTB3, which substantially improves the description of charged systems containing elements C, H, N, O, and P, especially regarding hydrogen binding energies and proton affinities. As a result, DFTB3 is particularly applicable to biomolecular systems. Remaining challenges and possible solutions are also briefly discussed.
Consequences of the cultivation of energy crops for the global nitrogen cycle.
Bouwman, A F; Van Grinsven, J J M; Eickhout, B
2010-01-01
In this paper, we assess the global consequences of implementing first- and second-generation bioenergy in the coming five decades, focusing on the nitrogen cycle. We use a climate mitigation scenario from the Organization for Economic Cooperation and Development's (OECD) Environmental Outlook, in which a carbon tax is introduced to stimulate production of biofuels from energy crops. In this scenario, the area of energy crops will increase from 8 Mha in the year 2000 to 270 Mha (14% of total cropland) and producing 5.6 Pg dry matter per year (12% of energy use) in 2050. This production requires an additional annual 19 Tg of N fertilizer in 2050 (15% of total), and this causes a global emission of 0.7 Tg of N2O-N (8% of agricultural emissions), 0.2 Tg NO-N (6%), and 2.2 Tg of NH3-N (5%). In addition, we project that 2.6 Tg of NO3(-)-N will leach from fields under energy crops. The emissions of N2O may be an important term in the greenhouse gas balance of biofuels produced from energy crops.
Roof-top solar energy potential under performance-based building energy codes: The case of Spain
DOE Office of Scientific and Technical Information (OSTI.GOV)
Izquierdo, Salvador; Montanes, Carlos; Dopazo, Cesar
2011-01-15
The quantification at regional level of the amount of energy (for thermal uses and for electricity) that can be generated by using solar systems in buildings is hindered by the availability of data for roof area estimation. In this note, we build on an existing geo-referenced method for determining available roof area for solar facilities in Spain to produce a quantitative picture of the likely limits of roof-top solar energy. The installation of solar hot water systems (SHWS) and photovoltaic systems (PV) is considered. After satisfying up to 70% (if possible) of the service hot water demand in every municipality,more » PV systems are installed in the remaining roof area. Results show that, applying this performance-based criterion, SHWS would contribute up to 1662 ktoe/y of primary energy (or 68.5% of the total thermal-energy demand for service hot water), while PV systems would provide 10 T W h/y of electricity (or 4.0% of the total electricity demand). (author)« less
Reasonable use of artificial lighting in building energy saving
NASA Astrophysics Data System (ADS)
Hou, Yuhan
2018-06-01
The architectural light environment is a crucial part of the built environment. Appropriate lighting can not only meet the needs of people's production and life, but also have a positive impact on people's mental state and feelings. Architectural lighting occupies a vital part of building energy consumption. At present, China's lighting electricity consumption has accounted for 12% of the total electricity generated in the country. Promoting lighting energy conservation can play an important role in alleviating energy shortages. This article mainly discusses how to make reasonable use of artificial lighting and choose suitable light sources to reduce the energy consumed by lighting under the condition of satisfying a good architectural light environment.
Final report - Magma Energy Research Project
DOE Office of Scientific and Technical Information (OSTI.GOV)
Colp, J.L.
1982-10-01
Scientific feasibility was demonstrated for the concept of magma energy extraction. The US magma resource is estimated at 50,000 to 500,000 quads of energy - a 700- to 7000-yr supply at the current US total energy use rate of 75 quads per year. Existing geophysical exploration systems are believed capable of locating and defining magma bodies and were demonstrated over a known shallow buried molten-rock body. Drilling rigs that can drill to the depths required to tap magma are currently available and experimental boreholes were drilled well into buried molten rock at temperatures up to 1100/sup 0/C. Engineering materials compatiblemore » with the buried magma environment are available and their performances were demonstrated in analog laboratory experiments. Studies show that energy can be extracted at attractive rates from magma resources in all petrologic compositions and physical configurations. Downhole heat extraction equipment was designed, built, and demonstrated successfully in buried molten rock and in the very hot margins surrounding it. Two methods of generating gaseous fuels in the high-temperature magmatic environment - generation of H/sub 2/ by the interaction of water with the ferrous iron and H/sub 2/, CH/sub 4/, and CO generation by the conversion of water-biomass mixtures - have been investigated and show promise.« less
Pilli, Sridhar; More, Tanaji; Yan, Song; Tyagi, Rajeshwar Dayal; Surampalli, Rao Y
2015-07-01
The effect of thermal pre-treatment on sludge anaerobic digestion (AD) efficiency was studied at different total solids (TS) concentrations (20.0, 30.0 and 40.0 g TS/L) and digestion times (0, 5, 10, 15, 20 and 30 days) for primary, secondary and mixed wastewater sludge. Moreover, sludge pre-treatment, AD and disposal processes were evaluated based on a mass-energy balance and corresponding greenhouse gas (GHG) emissions. Mass balance revealed that the least quantity of digestate was generated by thermal pre-treated secondary sludge at 30.0 g TS/L. The net energy (energy output-energy input) and energy ratio (energy output/energy input) for thermal pre-treated sludge was greater than control in all cases. The reduced GHG emissions of 73.8 × 10(-3) g CO2/g of total dry solids were observed for the thermal pre-treated secondary sludge at 30.0 g TS/L. Thermal pre-treatment of sludge is energetically beneficial and required less retention time compared to control. Copyright © 2015 Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Kawama, D.; Fujii, Y.; Gogami, T.; Hashimoto, O.; Kanda, H.; Maruta, T.; Matsumura, A.; Nakamura, S. N.; Shichijo, A.; Taniya, N.; Yamamoto, T.; Yokota, K.; Kato, S.; Tang, L.; Chen, C.; Ye, Z.; Yuan, L.; Reinhold, J.
2010-10-01
We are now preparing for the third generation (e, e'K+) Λ hypernuclear spectroscopic experiment at Hall C, Jefferson Lab (USA). The goal of the experiment is the precise spectroscopy of hypernuclei in wide mass region. We have constructed a new high resolution electron spectrometer "HES" dedicated to (e, e'K+) hypernuclear study. We can expect the total energy resolution of the experiment is about 350 keV(FWHM).
From discrete auroral arcs to the magnetospheric generator: numerical model and case study
NASA Astrophysics Data System (ADS)
Lamy, H.; Echim, M.; Cessateur, G.; Simon Wedlund, C.; Gustavsson, B.; Maggiolo, R.; Gunell, H.; Darrouzet, F.; De Keyser, J.
2017-12-01
We discuss an analysis method developed to estimate some of the properties of auroral generators (electron density, ne and temperature, Te), from ionospheric observations of the energy flux of precipitating electrons, e, measured across an auroral arc. The method makes use of a quasi-static magnetosphere-ionosphere coupling model. Assuming that the generator is a magnetospheric plasma interface, one obtains a parametric description of the generator electric field as a function of the kinetic and MHD properties of the interface. This description of the generator is introduced in a stationary M-I coupling model based on the current continuity in the topside ionosphere (Echim et al, 2007). The model is run iteratively for typical values of the magnetospheric ne and Te that are adjusted until the precipitating energy flux ɛ provided by the model at ionospheric altitudes fits the observations. The latter can be provided either in-situ by spacecraft measurements or remotely from optical ground-based observations. The method is illustrated by using the precipitating energy flux observed in-situ by DMSP on April 28, 2001, above a discrete auroral arc. For this particular date we have been able to compare the generator properties determined with our method with actual magnetospheric in-situ data provided by Cluster. The results compare very well and hence validate the method. The methodology is then applied on the energy flux of precipitating electrons estimated from optical images of a discrete auroral arc obtained simultaneously with the CCD cameras of the ALIS (Auroral Large Imaging System) network located in Scandinavia on 5 March 2008 (Simon Wedlund et al, 2013). Tomography-like techniques are used to retrieve the three-dimensional volume emission rates at 4278 Å from which the energy spectra of precipitating magnetospheric electrons can be further derived. These spectra are obtained along and across the arc, with a spatial resolution of approximately 3 km and provide E0, the characteristic energy and ɛ, the total flux energy of precipitating electrons. The generator properties are then estimated using the iterative technique validated with data from the DMSP-Cluster conjunction.
Plasma characterization for application in ballistics
DOE Office of Scientific and Technical Information (OSTI.GOV)
Katulka, G.; Nusca, M.; White, K.
1996-12-31
There is currently a strong motivation for improving the existing performance of fielded military gun systems. For that objective, research over the past several years has been carried out in an effort to enhance performance by addition of energy into the gun chamber by way of a plasma generator. This energy addition, referred to as Electro-thermal Chemical (ETC) propulsion, can be readily controlled electrically where it can be used to ignite the chamber`s energetic material, enhance the total energy, and control the interior process through control of the propellant combustion. To realize the potential advantages of this system it ismore » important to characterize the plasma generator in terms of (a) the impedance characteristics and its relationship to the pulse forming network used to generate the plasma, (b) the plasma output energy components such as radiation and convection in both time and space, (c) the details of the hydrodynamic interactions of the plasma with the propelling charge bed in the gun chamber and, (d) the direct effect of the plasma on the propellant reactions. Experimental studies have been carried out to study the effect of the plasma radiation on the propellant characteristics related to combustion.« less
Boemi, Sn; Papadopoulos, Am; Karagiannidis, A; Kontogianni, S
2010-11-01
Renewable energy sources (RES), excluding large hydroelectric plants, currently produce 4.21% of total electricity production in Greece. Even when considering the additional production from large hydroelectric plants, which accounts for some 7.8%, the distance to be covered towards the objective of 20% electricity produced from RES by 2010 and respectively towards 20% of total energy production by 2020 is discouraging. The potential, however, does exist; unfortunately so do serious barriers. On the other hand, solid waste management (SWM) is an issue that generates continuously increasing interest due to the extra amounts of solid waste generated; the lack of existing disposal facilities with adequate infrastructure and integrated management plans, also often accompanied by legislative and institutional gaps. However, socio-economic and public awareness problems are still met in the planning and implementation of RES and SWM projects, together with the lack of a complete national cadastre and a spatial development master plan, specifying areas eligible for RES and SWM development. Specific barriers occur for individual RES and the on-going inclusion of waste-derived renewable energy in the examined palette further increases the complexity of the entire issue. The consolidated study of this broad set of barriers was a main task of the present study which was carried out within the frame of a Hellenic-Canadian research project; the main results will be discussed herein.
NASA Astrophysics Data System (ADS)
Fajingbesi, F. E.; Midi, N. S.; Khan, S.
2017-06-01
Green energy sources or renewable energy system generally utilize modular approach in their design. This sort of power sources are generally in DC form or in single cases AC. Due to high fluctuation in the natural origin of this energy (wind & solar) source they are stored as DC. DC power however are difficult to transfer over long distances hence DC to AC converters and storage system are very important in green energy system design. In this work we have designed a novel multilevel DC to AC converter that takes into account the modular design of green energy systems. A power conversion efficiency of 99% with reduced total harmonic distortion (THD) was recorded from our simulated system design.
Assessment of On-Site Power Opportunities in the Industrial Sector
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bryson, T.
2001-10-08
The purpose of this report is to identify the potential for on-site power generation in the U.S. industrial sector with emphasis on nine industrial groups called the ''Industries of the Future'' (IOFs) by the U.S. Department of Energy (DOE). Through its Office of Industrial Technologies (OIT), the DOE has teamed with the IOFs to develop collaborative strategies for improving productivity, global competitiveness, energy usage and environmental performance. Total purchases for electricity and steam for the IOFs are in excess of $27 billion annually. Energy-related costs are very significant for these industries. The nine industrial groups are (1) Agriculture (SIC 1);more » (2) Forest products; (3) Lumber and wood products (SIC 24); (4) Paper and allied products (SIC 26); (5) Mining (SIC 11, 12, 14); (6) Glass (SIC 32); (7) Petroleum (SIC 29); (8) Chemicals (SIC 28); and (9) Metals (SIC 33): Steel, Aluminum, and Metal casting. Although not currently part of the IOF program, the food industry is included in this report because of its close relationship to the agricultural industry and its success with on-site power generation. On-site generation provides an alternative means to reduce energy costs, comply with environmental regulations, and ensure a reliable power supply. On-site generation can ease congestion in the local utility's electric grid. Electric market restructuring is exacerbating the price premium for peak electricity use and for reliability, creating considerable market interest in on-site generation.« less
Tidal Turbine Array Optimization Based on the Discrete Particle Swarm Algorithm
NASA Astrophysics Data System (ADS)
Wu, Guo-wei; Wu, He; Wang, Xiao-yong; Zhou, Qing-wei; Liu, Xiao-man
2018-06-01
In consideration of the resource wasted by unreasonable layout scheme of tidal current turbines, which would influence the ratio of cost and power output, particle swarm optimization algorithm is introduced and improved in the paper. In order to solve the problem of optimal array of tidal turbines, the discrete particle swarm optimization (DPSO) algorithm has been performed by re-defining the updating strategies of particles' velocity and position. This paper analyzes the optimization problem of micrositing of tidal current turbines by adjusting each turbine's position, where the maximum value of total electric power is obtained at the maximum speed in the flood tide and ebb tide. Firstly, the best installed turbine number is generated by maximizing the output energy in the given tidal farm by the Farm/Flux and empirical method. Secondly, considering the wake effect, the reasonable distance between turbines, and the tidal velocities influencing factors in the tidal farm, Jensen wake model and elliptic distribution model are selected for the turbines' total generating capacity calculation at the maximum speed in the flood tide and ebb tide. Finally, the total generating capacity, regarded as objective function, is calculated in the final simulation, thus the DPSO could guide the individuals to the feasible area and optimal position. The results have been concluded that the optimization algorithm, which increased 6.19% more recourse output than experience method, can be thought as a good tool for engineering design of tidal energy demonstration.
Applications of the Renewable Energy Network Optimization Tool
NASA Astrophysics Data System (ADS)
Alliss, R.; Link, R.; Apling, D.; Kiley, H.; Mason, M.; Darmenova, K.
2010-12-01
As the renewable energy industry continues to grow so does the requirement for atmospheric modeling and analysis tools to maximize both wind and solar power. Renewable energy generation is variable however; presenting challenges for electrical grid operation and requires a variety of measures to adequately firm power. These measures include the production of non-renewable generation during times when renewables are not available. One strategy for minimizing the variability of renewable energy production is site diversity. Assuming that a network of renewable energy systems feed a common electrical grid, site diversity ensures that when one system on the network has a reduction in generation others on the same grid make up the difference. The site-diversity strategy can be used to mitigate the intermittency in alternative energy production systems while still maximizing saleable energy. The Renewable Energy Network Optimization Tool (ReNOT) has recently been developed to study the merits of site optimization for wind farms. The modeling system has a plug-in architecture that allows us to accommodate a wide variety of renewable energy system designs and performance metrics. The Weather Research and Forecasting (WRF) mesoscale model is applied to generate high-resolution wind databases to support the site selection of wind farms. These databases are generated on High Performance Computing systems such as the Rocky Mountain Supercomputing Center (RMSC). The databases are then accessed by ReNOT and an optimized site selection is developed. We can accommodate numerous constraints (e.g., number of sites, the geographic extent of the optimization, proximity to high-voltage transport lines, etc.). As part of our collaboration with RMSC and the State of Montana a study was performed to estimate the optimal locations of a network of wind farms. Comparisons were made to four existing wind farm locations in Montana including Glacier with a 210 MW name plate capacity, Horseshoe Bend with a total capacity of 9 MW, Diamond Willow with a capacity of 20MW and Judith Gap with a total capacity of 135 MW. The goal of this study was to see if ReNOT could find a four site network that made more effective use of the existing four site network of wind farms' 374 MW nameplate capacity. We developed three different metrics in which to pick sites. Metric 3 (M3) picks sites based on the previous day's mean power, and accounts for short-term variability (i.e., 1 hour). M3 attempts to approximate usable power by minimizing ramping events which are so important to industry. In addition we investigated several performance metrics including Mean Power, Usable Power, and ramping event frequency. A ramping event is defined as an increase or decrease in power production over the course of one hour. Of interest was the frequency of ramping events that exceeded 10% of total capacity for the network. Networks with few ramping events are markedly superior to networks producing otherwise identical aggregate power. The optimization was run over the 15-year period of hub-height wind data (40 meters AGL). The ReNOT derived network produces 58% more usable power than the four existing and operating wind farms. In addition, the optimized four site network produces three times fewer significant ramping events.
Hahn, Henning; Hartmann, Kilian; Bühle, Lutz; Wachendorf, Michael
2015-03-01
The environmental performance of biogas plant configurations for a demand - oriented biogas supply for flexible power generation is comparatively assessed in this study. Those configurations indicate an increased energy demand to operate the operational enhancements compared to conventional biogas plants supplying biogas for baseload power generation. However, findings show that in contrast to an alternative supply of power generators with natural gas, biogas supplied on demand by adapted biogas plant configurations saves greenhouse gas emissions by 54-65 g CO(2-eq) MJ(-1) and primary energy by about 1.17 MJ MJ(-1). In this regard, configurations with flexible biogas production profit from reduced biogas storage requirements and achieve higher savings compared to configurations with continuous biogas production. Using thicker biogas storage sheeting material reduces the methane permeability of up to 6m(3) d(-1) which equals a reduction of 8% of the configuration's total methane emissions. Copyright © 2014 Elsevier Ltd. All rights reserved.
Choi, Sanghun; Choi, Jiwoong; Lin, Ching-Long
2018-01-01
The aim of this study was to investigate and quantify contributions of kinetic energy and viscous dissipation to airway resistance during inspiration and expiration at various flow rates in airway models of different bifurcation angles. We employed symmetric airway models up to the 20th generation with the following five different bifurcation angles at a tracheal flow rate of 20 L/min: 15 deg, 25 deg, 35 deg, 45 deg, and 55 deg. Thus, a total of ten computational fluid dynamics (CFD) simulations for both inspiration and expiration were conducted. Furthermore, we performed additional four simulations with tracheal flow rate values of 10 and 40 L/min for a bifurcation angle of 35 deg to study the effect of flow rate on inspiration and expiration. Using an energy balance equation, we quantified contributions of the pressure drop associated with kinetic energy and viscous dissipation. Kinetic energy was found to be a key variable that explained the differences in airway resistance on inspiration and expiration. The total pressure drop and airway resistance were larger during expiration than inspiration, whereas wall shear stress and viscous dissipation were larger during inspiration than expiration. The dimensional analysis demonstrated that the coefficients of kinetic energy and viscous dissipation were strongly correlated with generation number. In addition, the viscous dissipation coefficient was significantly correlated with bifurcation angle and tracheal flow rate. We performed multiple linear regressions to determine the coefficients of kinetic energy and viscous dissipation, which could be utilized to better estimate the pressure drop in broader ranges of successive bifurcation structures.
Total Energy Concepts as Applied to Universities.
ERIC Educational Resources Information Center
Gudgeon, R.L.
A comprehensive discussion of single fuel source generation of power and heating requirements is presented. Definition and explanation of system concepts includes--(1) heat pumps, (2) steam turbines, (3) gas turbines, and (4) gas and diesel engines. Concept cost evaluation factors described are--(1) load pattern, (2) campus configuration, (3) fuel…
Fossil fuel burning is considered a major contributor to global climate change. The outlook for production and consumption of fossil fuels int he US indicates continued growth to support growing energy demands. For example, coal-generated electricity is projected ot increase from...
Pryor, S. C.; Barthelmie, R. J.
2011-01-01
The energy sector comprises approximately two-thirds of global total greenhouse gas emissions. For this and other reasons, renewable energy resources including wind power are being increasingly harnessed to provide electricity generation potential with negligible emissions of carbon dioxide. The wind energy resource is naturally a function of the climate system because the “fuel” is the incident wind speed and thus is determined by the atmospheric circulation. Some recent articles have reported historical declines in measured near-surface wind speeds, leading some to question the continued viability of the wind energy industry. Here we briefly articulate the challenges inherent in accurately quantifying and attributing historical tendencies and making robust projections of likely future wind resources. We then analyze simulations from the current generation of regional climate models and show, at least for the next 50 years, the wind resource in the regions of greatest wind energy penetration will not move beyond the historical envelope of variability. Thus this work suggests that the wind energy industry can, and will, continue to make a contribution to electricity provision in these regions for at least the next several decades. PMID:21536905
Pryor, S C; Barthelmie, R J
2011-05-17
The energy sector comprises approximately two-thirds of global total greenhouse gas emissions. For this and other reasons, renewable energy resources including wind power are being increasingly harnessed to provide electricity generation potential with negligible emissions of carbon dioxide. The wind energy resource is naturally a function of the climate system because the "fuel" is the incident wind speed and thus is determined by the atmospheric circulation. Some recent articles have reported historical declines in measured near-surface wind speeds, leading some to question the continued viability of the wind energy industry. Here we briefly articulate the challenges inherent in accurately quantifying and attributing historical tendencies and making robust projections of likely future wind resources. We then analyze simulations from the current generation of regional climate models and show, at least for the next 50 years, the wind resource in the regions of greatest wind energy penetration will not move beyond the historical envelope of variability. Thus this work suggests that the wind energy industry can, and will, continue to make a contribution to electricity provision in these regions for at least the next several decades.
An energy harvesting converter to power sensorized total human knee prosthesis
NASA Astrophysics Data System (ADS)
Luciano, V.; Sardini, E.; Serpelloni, M.; Baronio, G.
2014-02-01
Monitoring the internal loads acting in a total knee prosthesis (TKP) is fundamental aspect to improve their design. One of the main benefits of this improvement is the longer duration of the tibial inserts. In this work, an electromagnetic energy harvesting system, which is implantable in a TKP, is presented. This is conceived for powering a future implantable system that is able to monitor the loads (and, possibly, other parameters) that could influence the working conditions of a TKP in real-time. The energy harvesting system (EHS) is composed of two series of NdFeB magnets, positioned into each condyle, and a coil that is placed in a pin of the tibial insert and connected to an implantable power management circuit. The magnetic flux variation and the induced voltage are generated by the knee's motion. A TKP prototype has been realized in order to reproduce the knee mechanics and to test the EHS performance. In the present work, the experimental results are obtained by adopting a resistive load of 2.2 kΩ, in order to simulate a real implanted autonomous system with a current consumption of 850 µA and voltage of 2 V. The tests showed that, after 7 to 30 s of walking with a gait cycle frequency of about 1.0 Hz, the EHS can generate an energy of about 70 μJ, guaranteeing a voltage between 2 and 1.4 V every 7.6 s. With this prototype we can verify that it is possible to power for 16 ms a circuit having a power consumption of 1.7 mW every 7.6 s. The proposed generator is a viable solution to power an implanted electronic system that is conceived for measuring and transmitting the TKP load parameters.
Optimising the selection of food items for FFQs using Mixed Integer Linear Programming.
Gerdessen, Johanna C; Souverein, Olga W; van 't Veer, Pieter; de Vries, Jeanne Hm
2015-01-01
To support the selection of food items for FFQs in such a way that the amount of information on all relevant nutrients is maximised while the food list is as short as possible. Selection of the most informative food items to be included in FFQs was modelled as a Mixed Integer Linear Programming (MILP) model. The methodology was demonstrated for an FFQ with interest in energy, total protein, total fat, saturated fat, monounsaturated fat, polyunsaturated fat, total carbohydrates, mono- and disaccharides, dietary fibre and potassium. The food lists generated by the MILP model have good performance in terms of length, coverage and R 2 (explained variance) of all nutrients. MILP-generated food lists were 32-40 % shorter than a benchmark food list, whereas their quality in terms of R 2 was similar to that of the benchmark. The results suggest that the MILP model makes the selection process faster, more standardised and transparent, and is especially helpful in coping with multiple nutrients. The complexity of the method does not increase with increasing number of nutrients. The generated food lists appear either shorter or provide more information than a food list generated without the MILP model.
A sensor-less LED dimming system based on daylight harvesting with BIPV systems.
Yoo, Seunghwan; Kim, Jonghun; Jang, Cheol-Yong; Jeong, Hakgeun
2014-01-13
Artificial lighting in office buildings typically requires 30% of the total energy consumption of the building, providing a substantial opportunity for energy savings. To reduce the energy consumed by indoor lighting, we propose a sensor-less light-emitting diode (LED) dimming system using daylight harvesting. In this study, we used light simulation software to quantify and visualize daylight, and analyzed the correlation between photovoltaic (PV) power generation and indoor illumination in an office with an integrated PV system. In addition, we calculated the distribution of daylight illumination into the office and dimming ratios for the individual control of LED lights. Also, we were able directly to use the electric power generated by PV system. As a result, power consumption for electric lighting was reduced by 40 - 70% depending on the season and the weather conditions. Thus, the dimming system proposed in this study can be used to control electric lighting to reduce energy use cost-effectively and simply.
Internal Waves in the East Australian Current
NASA Astrophysics Data System (ADS)
Alford, Matthew H.; Sloyan, Bernadette M.; Simmons, Harper L.
2017-12-01
Internal waves, which drive most ocean turbulence and add "noise" to lower-frequency records, interact with low-frequency current systems and topography in yet poorly known ways. Taking advantage of a heavily instrumented, 14 month mooring array, internal waves in the East Australian Current (EAC) are examined for the first time. Internal wave horizontal kinetic energy (HKE) is within a factor of 2 of the Garrett-Munk (1976) spectrum. Continuum internal waves, near-inertial waves, and internal tides together constitute a significant percentage of the total velocity variance. Mode-1 internal tide energy fluxes are southward and much smaller than energy times group velocity, consistent with reflection at the continental slope of incident waves generated from near New Caledonia and the Solomon Islands. Internal tide HKE is highly phase variable, consistent with refraction by the variable EAC. Mode-1 near-inertial wave energy fluxes are of comparable magnitude and are equatorward and episodic, consistent with generation by storms farther poleward. These processes are considered together in the complex environment of the EAC.
AC power generation from microbial fuel cells
NASA Astrophysics Data System (ADS)
Lobo, Fernanda Leite; Wang, Heming; Forrestal, Casey; Ren, Zhiyong Jason
2015-11-01
Microbial fuel cells (MFCs) directly convert biodegradable substrates to electricity and carry good potential for energy-positive wastewater treatment. However, the low and direct current (DC) output from MFC is not usable for general electronics except small sensors, yet commercial DC-AC converters or inverters used in solar systems cannot be directly applied to MFCs. This study presents a new DC-AC converter system for MFCs that can generate alternating voltage in any desired frequency. Results show that AC power can be easily achieved in three different frequencies tested (1, 10, 60 Hz), and no energy storage layer such as capacitors was needed. The DC-AC converter efficiency was higher than 95% when powered by either individual MFCs or simple MFC stacks. Total harmonic distortion (THD) was used to investigate the quality of the energy, and it showed that the energy could be directly usable for linear electronic loads. This study shows that through electrical conversion MFCs can be potentially used in household electronics for decentralized off-grid communities.
NASA Astrophysics Data System (ADS)
Lee, Keun
Renewable energy in different forms has been used in various applications for survival since the beginning of human existence. However, there is a new dire need to reevaluate and recalibrate the overall energy issue both nationally and globally. This includes, but is not limited to, the finite availability of fossil fuel, energy sustainability with an increasing demand, escalating energy costs, environmental impact such as global warming and green-house gases, to name a few. This dissertation is primarily focused and related to the production and usage of electricity from non-hydro renewable sources. Among non-hydro renewable energy sources, electricity generation from wind and solar energy are the fastest-growing technologies in the United States and in the world. However, due to the intermittent nature of such renewable sources, energy storage devices are required to maintain proper operation of the grid system and in order to increase reliability. A hybrid system, as the name suggests, is a combination of different forms of non-renewable and renewable energy generation, with or without storage devices. Hybrid systems, when applied properly, are able to improve reliability and enhance stability, reduce emissions and noise pollution, provide continuous power, increase operation life, reduce cost, and efficiently use all available energy. In the United States (U.S.), buildings consume approximately 40% of the total primary energy and 74% of the total electricity. Therefore, reduction of energy consumption and improved energy efficiency in U.S. buildings will play a vital role in the overall energy picture. Electrical energy usage for any such building varies widely depending on age (construction technique), electricity and natural gas usage, appearance, location and climate. In this research, a hybrid system including non-renewable and renewable energy generation with storage devices specifically for building applications, is studied in detail. This research deals with the optimization of the hybrid system design (which consists of PV panels and/or wind turbines and/or storage devices for building applications) by developing an algorithm designed to make the system cost effective and energy efficient. Input data includes electrical load demand profile of the buildings, buildings' structural and geographical characteristics, real time pricing of electricity, and the costs of hybrid systems and storage devices. When the electrical load demand profile of a building that is being studied is available, a measured demand profile is directly used as input data. However, if that information is not available, a building's electric load demand is estimated using a developed algorithm based on three large data sources from a public domain, and used as input data. Using the acquired input data, the algorithm of this research is designed and programmed in order to determine the size of renewable components and to minimize the total yearly net cost. This dissertation also addresses the parametric sensitivity analysis to determine which factors are more significant and are expected to produce useful guidelines in the decision making process. An engineered and more practical, simplified solution has been provided for the optimized design process.
NASA Astrophysics Data System (ADS)
Ghenai, C.; Bettayeb, M.
2017-11-01
Modelling, simulation, optimization and control strategies are used in this study to design a stand-alone solar PV/Fuel Cell/Battery/Generator hybrid power system to serve the electrical load of a commercial building. The main objective is to design an off grid energy system to meet the desired electric load of the commercial building with high renewable fraction, low emissions and low cost of energy. The goal is to manage the energy consumption of the building, reduce the associate cost and to switch from grid-tied fossil fuel power system to an off grid renewable and cleaner power system. Energy audit was performed in this study to determine the energy consumption of the building. Hourly simulations, modelling and optimization were performed to determine the performance and cost of the hybrid power configurations using different control strategies. The results show that the hybrid off grid solar PV/Fuel Cell/Generator/Battery/Inverter power system offers the best performance for the tested system architectures. From the total energy generated from the off grid hybrid power system, 73% is produced from the solar PV, 24% from the fuel cell and 3% from the backup Diesel generator. The produced power is used to meet all the AC load of the building without power shortage (<0.1%). The hybrid power system produces 18.2% excess power that can be used to serve the thermal load of the building. The proposed hybrid power system is sustainable, economically viable and environmentally friendly: High renewable fraction (66.1%), low levelized cost of energy (92 /MWh), and low carbon dioxide emissions (24 kg CO2/MWh) are achieved.
NASA Astrophysics Data System (ADS)
Oda, Takuya; Akisawa, Atushi; Kashiwagi, Takao
If the economic activity in the commercial and residential sector continues to grow, improvement in energy conversion efficiencies of energy supply systems is necessary for CO2 mitigation. In recent years, the electricity driven hot water heat pump (EDHP) and the solar photo voltaic (PV) are commercialized. The fuel cell (FC) of co-generation system (CGS) for the commercial and residential sector will be commercialized in the future. The aim is to indicate the ideal energy supply system of the users sector, which both manages the economical cost and CO2 mitigation, considering the grid power system. In the paper, cooperative Japanese energy supply systems are modeled by linear-programming. It includes the grid power system and energy systems of five commercial sectors and a residential sector. The demands of sectors are given by the objective term for 2005 to 2025. 24 hours load for each 3 annual seasons are considered. The energy systems are simulated to be minimize the total cost of energy supply, and to be mitigate the CO2 discharge. As result, the ideal energy system at 2025 is shown. The CGS capacity grows to 30% (62GW) of total power system, and the EDHP capacity is 26GW, in commercial and residential sectors.
NASA Astrophysics Data System (ADS)
Yayathi, Sandeep; Walker, William; Doughty, Daniel; Ardebili, Haleh
2016-10-01
Lithium ion (Li-ion) batteries provide low mass and energy dense solutions necessary for space exploration, but thermal related safety concerns impede the utilization of Li-ion technology for human applications. Experimental characterization of thermal runaway energy release with accelerated rate calorimetry supports safer thermal management systems. 'Standard' accelerated rate calorimetry setup provides means to measure the addition of energy exhibited through the body of a Li-ion cell. This study considers the total energy generated during thermal runaway as distributions between cell body and hot gases via inclusion of a unique secondary enclosure inside the calorimeter; this closed system not only contains the cell body and gaseous species, but also captures energy release associated with rapid heat transfer to the system unobserved by measurements taken on the cell body. Experiments include Boston Power Swing 5300, Samsung 18650-26F and MoliCel 18650-J Li-ion cells at varied states-of-charge. An inverse relationship between state-of-charge and onset temperature is observed. Energy contained in the cell body and gaseous species are successfully characterized; gaseous energy is minimal. Significant additional energy is measured with the heating of the secondary enclosure. Improved calorimeter apparatus including a secondary enclosure provides essential capability to measuring total energy release distributions during thermal runaway.
Medical aspects of power generation, present and future.
Linnemann, R E
1979-01-01
It can be seen that the radiation emissions of nuclear power plants are small indeed, compared to natural background radiation and other man-made sources of radiation. For example, the poulation is exposed to 100 times more radiation from television sets than from nuclear power reactors. The assumed risks to the people in this country from nuclear power reactors are also small compared to the normal risks which are tolerated in this society. The complete elimination of all hazards is a most difficult if not impossible task. If we need and desire a certain level of electrical energy, if we must choose between alternative sourves of the energy, then it is apparent that the total impact on our health from nuclear power generation of electricity, under normal operations and in consideration of catastrophic accident probabilities, is significantly less than that of continuing or increasing use of fossil fuels to generate electricity.
NASA Technical Reports Server (NTRS)
Wilreker, V. F.; Stiller, P. H.; Scott, G. W.; Kruse, V. J.; Smith, R. F.
1984-01-01
Assessing the performance of a MOD-OA horizontal axis wind turbine connected to an isolated diesel utility, a comprehensive data measurement program was conducted on the Block Island Power Company installation on Block Island, Rhode Island. The detailed results of that program focusing on three principal areas of (1) fuel displacement (savings), (2) dynamic interaction between the diesel utility and the wind turbine, (3) effects of three models of wind turbine reactive power control are presented. The approximate two month duration of the data acquisition program conducted in the winter months (February into April 1982) revealed performance during periods of highest wind energy penetration and hence severity of operation. Even under such conditions fuel savings were significant resulting in a fuel reduction of 6.7% while the MOD-OA was generating 10.7% of the total electrical energy. Also, electrical disturbance and interactive effects were of an acceptable level.
Regimes of enhanced electromagnetic emission in beam-plasma interactions
NASA Astrophysics Data System (ADS)
Timofeev, I. V.; Annenkov, V. V.; Arzhannikov, A. V.
2015-11-01
The ways to improve the efficiency of electromagnetic waves generation in laboratory experiments with high-current relativistic electron beams injected into a magnetized plasma are discussed. It is known that such a beam can lose, in a plasma, a significant part of its energy by exciting a high level of turbulence and heating plasma electrons. Beam-excited plasma oscillations may simultaneously participate in nonlinear processes resulting in a fundamental and second harmonic emissions. It is obvious, however, that in the developed plasma turbulence the role of these emissions in the total energy balance is always negligible. In this paper, we investigate whether electromagnetic radiation generated in the beam-plasma system can be sufficiently enhanced by the direct linear conversion of resonant beam-driven modes into electromagnetic ones on preformed regular inhomogeneities of plasma density. Due to the high power of relativistic electron beams, the mechanism discussed may become the basis for the generator of powerful sub-terahertz radiation.
Materials and energy flow in the life cycle of leather: a case study of Bangladesh
NASA Astrophysics Data System (ADS)
Chowdhury, Zia Uddin Md.; Ahmed, Tanvir; Hashem, Md. Abul
2018-05-01
This article presents the results of the materials and energy flow analysis for leather produced in Bangladesh and establishes an inventory for the life cycle assessment. Also, a comparison is made with the material and energy flow of the Indian leather. A cradle to gate analysis is performed for full-chrome leather (FCL), a representative leather article from an export-oriented industry in Bangladesh, taking into consideration the main processes associated with leather production and the corresponding materials and energy input. Data was collected on annual wet-salted rawhide consumption, water, and steam consumption, chemicals requirement, tannery solid waste generation, electricity, fuel oil use for the generator and steam boiler. Moreover, an analysis of the physical and chemical properties of wastewater emissions of the different leather unit processes was performed. The input and output profiles of the FCL were compared to those of an Indian leather. It was seen that FCL consumed water 2 times higher than the Indian leather while the electricity consumption of Indian leather was almost 2 times higher than its Bangladeshi counterpart. The Indian leather had significantly higher carbon footprint (in terms of CO2 equivalent emission) mainly because of the consumption of grid electricity that comes from coal-based power generation. Wastewater parameters such as chloride, Total Dissolved Solids (TDS) and Total Solids (TS) for the Indian leather are more than 4.5, 3 and 3 times higher respectively than that of corresponding emissions for the Bangladeshi FCL, which can be attributed to the higher use of inorganic salts in the process. Despite similar input of chromium compounds for both the leathers, the emission of total chromium was slightly higher in the case of Indian leather probably due to lower uptake of chromium by the substrate. Bangladeshi FCL used twice in the amount of (NH4)2SO4 than India, which may be responsible for the higher BOD load in the wastewater. It can also be seen that a significant amount of rawhide input is not converted into the usable leather as demonstrated by the high proportion of solid waste generation (70% and 55% for Bangladeshi FCL and Indian leather respectively). This study highlights that wide variations exist in the materials and energy flows from different tanneries. Understanding these variations is essential to pinpoint areas where resources can be used more efficiently and optimally in the leather manufacturing process.
Geothermal energy program overview
NASA Astrophysics Data System (ADS)
1991-12-01
The mission of the Geothermal Energy Program is to develop the science and technology necessary for tapping our nation's tremendous heat energy sources contained within the Earth. Geothermal energy is a domestic energy source that can produce clean, reliable, cost-effective heat and electricity for our nation's energy needs. Geothermal energy - the heat of the Earth - is one of our nation's most abundant energy resources. In fact, geothermal energy represents nearly 40 percent of the total U.S. energy resource base and already provides an important contribution to our nation's energy needs. Geothermal energy systems can provide clean, reliable, cost-effective energy for our nation's industries, businesses, and homes in the form of heat and electricity. The U.S. Department of Energy's (DOE) Geothermal Energy Program sponsors research aimed at developing the science and technology necessary for utilizing this resource more fully. Geothermal energy originates from the Earth's interior. The hottest fluids and rocks at accessible depths are associated with recent volcanic activity in the western states. In some places, heat comes to the surface as natural hot water or steam, which have been used since prehistoric times for cooking and bathing. Today, wells convey the heat from deep in the Earth to electric generators, factories, farms, and homes. The competitiveness of power generation with lower quality hydrothermal fluids, geopressured brines, hot dry rock, and magma (the four types of geothermal energy), still depends on the technical advancements sought by DOE's Geothermal Energy Program.
Alternative Energy Development and China's Energy Future
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zheng, Nina; Fridley, David
2011-06-15
In addition to promoting energy efficiency, China has actively pursued alternative energy development as a strategy to reduce its energy demand and carbon emissions. One area of particular focus has been to raise the share of alternative energy in China’s rapidly growing electricity generation with a 2020 target of 15% share of total primary energy. Over the last ten years, China has established several major renewable energy regulations along with programs and subsidies to encourage the growth of non-fossil alternative energy including solar, wind, nuclear, hydro, geothermal and biomass power as well as biofuels and coal alternatives. This study thusmore » seeks to examine China’s alternative energy in terms of what has and will continue to drive alternative energy development in China as well as analyze in depth the growth potential and challenges facing each specific technology. This study found that despite recent policies enabling extraordinary capacity and investment growth, alternative energy technologies face constraints and barriers to growth. For relatively new technologies that have not achieved commercialization such as concentrated solar thermal, geothermal and biomass power, China faces technological limitations to expanding the scale of installed capacity. While some alternative technologies such as hydropower and coal alternatives have been slowed by uneven and often changing market and policy support, others such as wind and solar PV have encountered physical and institutional barriers to grid integration. Lastly, all alternative energy technologies face constraints in human resources and raw material resources including land and water, with some facing supply limitations in critical elements such as uranium for nuclear, neodymium for wind and rare earth metals for advanced solar PV. In light of China’s potential for and barriers to growth, the resource and energy requirement for alternative energy technologies were modeled and scenario analysis used to evaluate the energy and emission impact of two pathways of alternative energy development. The results show that China can only meets its 2015 and 2020 targets for non-fossil penetration if it successfully achieves all of its capacity targets for 2020 with continued expansion through 2030. To achieve this level of alternative generation, significant amounts of raw materials including 235 Mt of concrete, 54 Mt of steel, 5 Mt of copper along with 3 billion tons of water and 64 thousand square kilometers of land are needed. China’s alternative energy supply will likely have relatively high average energy output to fossil fuel input ratio of 42 declining to 26 over time, but this ratio is largely skewed by nuclear and hydropower capacity. With successful alternative energy development, 32% of China’s electricity and 21% of its total primary energy will be supplied by alternative energy by 2030. Compared to the counterfactual baseline in which alternative energy development stumbles and China does not meet its capacity targets until 2030, alternative energy development can displace 175 Mtce of coal inputs per year and 2080 Mtce cumulatively from power generation by 2030. In carbon terms, this translates into 5520 Mt of displaced CO 2 emissions over the twenty year period, with more than half coming from expanded nuclear and wind power generation. These results illustrate the critical role that alternative energy development can play alongside energy efficiency in reducing China’s energy-related carbon emissions.« less
NASA Astrophysics Data System (ADS)
Jelínek, M.; Kubeček, V.; Čech, M.; Hiršl, P.
2011-03-01
A quasi-continuously pumped picosecond oscillator-amplifier laser system based on two identical 2.4% Nd:YAG slabs in a single bounce geometry was developed and investigated. The oscillator was passively mode locked by the multiple quantum well saturable absorber inserted into the resonator in transmission mode. Output train containing 7 pulses with total energy of 900 μJ was generated directly from the oscillator. Single pulse with energy of 75 μJ, duration of 113 ps and Gaussian spatial profile was cavity dumped from the resonator and amplified by the single pass amplifier to the energy of 830 μJ. Comparison with our previously reported data obtained with similar system based on Nd:GdVO4 shows advantage of using highly doped Nd:YAG for generation of sub-millijoule pulses in one hundred picoseconds range, which might be interesting in many applications.
Results of investigation of muon fluxes of superhigh energy cosmic rays with X-ray emulsion chambers
NASA Technical Reports Server (NTRS)
Ivanenko, I. P.; Ivanova, M. A.; Kuzmichev, L. A.; Ilyina, N. P.; Mandritskaya, K. V.; Osipova, E. A.; Rakobolskaya, I. V.; Zatsepin, G. T.
1985-01-01
The overall data from the investigation of the cosmic ray muon flux in the range of zenith angles (0-90) deg within the energy range (3.5 to 5.0) TeV is presented. The exposure of large X-ray emulsion chambers underground was 1200 tons. year. The data were processe using the method which was applied in the experiment Pamir and differred from the earlier applied one. The obtained value of a slope power index of the differential energy spectrum of the global muon flux is =3.7 that corresponds to the slope of the pion generation differential spectrum, gamma sub PI = 2.75 + or - .04. The analysis of the muon zenith-angular distribution showed that the contribution of rapid generation muons in the total muon flux agree the best with the value .2% and less with .7% at a 90% reliability level.
Energy conversion approaches and materials for high-efficiency photovoltaics.
Green, Martin A; Bremner, Stephen P
2016-12-20
The past five years have seen significant cost reductions in photovoltaics and a correspondingly strong increase in uptake, with photovoltaics now positioned to provide one of the lowest-cost options for future electricity generation. What is becoming clear as the industry develops is that area-related costs, such as costs of encapsulation and field-installation, are increasingly important components of the total costs of photovoltaic electricity generation, with this trend expected to continue. Improved energy-conversion efficiency directly reduces such costs, with increased manufacturing volume likely to drive down the additional costs associated with implementing higher efficiencies. This suggests the industry will evolve beyond the standard single-junction solar cells that currently dominate commercial production, where energy-conversion efficiencies are fundamentally constrained by Shockley-Queisser limits to practical values below 30%. This Review assesses the overall prospects for a range of approaches that can potentially exceed these limits, based on ultimate efficiency prospects, material requirements and developmental outlook.
Renewable energy projects in the Dominican Republic
DOE Office of Scientific and Technical Information (OSTI.GOV)
Viani, B.
1997-12-01
This paper describes a US/Dominican Republic program to develop renewable energy projects in the country. The objective is to demonstrate the commercial viability of renewable energy generation projects, primarily small-scale wind and hydropower. Preliminary studies are completed for three micro-hydro projects with a total capacity of 262 kWe, and two small wind power projects for water pumping. In addition wind resource assessment is ongoing, and professional training and technical assistance to potential investors is ongoing. Projects goals include not less than ten small firms actively involved in installation of such systems by September 1998.
Geothermal pump down-hole energy regeneration system
Matthews, Hugh B.
1982-01-01
Geothermal deep well energy extraction apparatus is provided of the general kind in which solute-bearing hot water is pumped to the earth's surface from a subterranean location by utilizing thermal energy extracted from the hot water for operating a turbine motor for driving an electrical power generator at the earth 3 s surface, the solute bearing water being returned into the earth by a reinjection well. Efficiency of operation of the total system is increased by an arrangement of coaxial conduits for greatly reducing the flow of heat from the rising brine into the rising exhaust of the down-well turbine motor.
Enhanced laser-energy coupling to dense plasmas driven by recirculating electron currents
NASA Astrophysics Data System (ADS)
Gray, R. J.; Wilson, R.; King, M.; Williamson, S. D. R.; Dance, R. J.; Armstrong, C.; Brabetz, C.; Wagner, F.; Zielbauer, B.; Bagnoud, V.; Neely, D.; McKenna, P.
2018-03-01
The absorption of laser energy and dynamics of energetic electrons in dense plasma is fundamental to a range of intense laser-driven particle and radiation generation mechanisms. We measure the total reflected and scattered laser energy as a function of intensity, distinguishing between the influence of pulse energy and focal spot size on total energy absorption, in the interaction with thin foils. We confirm a previously published scaling of absorption with intensity by variation of laser pulse energy, but find a slower scaling when changing the focal spot size. 2D particle-in-cell simulations show that the measured differences arise due to energetic electrons recirculating within the target and undergoing multiple interactions with the laser pulse, which enhances absorption in the case of large focal spots. This effect is also shown to be dependent on the laser pulse duration, the target thickness and the electron beam divergence. The parameter space over which this absorption enhancement occurs is explored via an analytical model. The results impact our understanding of the fundamental physics of laser energy absorption in solids and thus the development of particle and radiation sources driven by intense laser–solid interactions.
Neutron Capture Energies for Flux Normalization and Approximate Model for Gamma-Smeared Power
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kim, Kang Seog; Clarno, Kevin T.; Liu, Yuxuan
The Consortium for Advanced Simulation of Light Water Reactors (CASL) Virtual Environment for Reactor Applications (VERA) neutronics simulator MPACT has used a single recoverable fission energy for each fissionable nuclide assuming that all recoverable energies come only from fission reaction, for which capture energy is merged with fission energy. This approach includes approximations and requires improvement by separating capture energy from the merged effective recoverable energy. This report documents the procedure to generate recoverable neutron capture energies and the development of a program called CapKappa to generate capture energies. Recoverable neutron capture energies have been generated by using CapKappa withmore » the evaluated nuclear data file (ENDF)/B-7.0 and 7.1 cross section and decay libraries. The new capture kappas were compared to the current SCALE-6.2 and the CASMO-5 capture kappas. These new capture kappas have been incorporated into the Simplified AMPX 51- and 252-group libraries, and they can be used for the AMPX multigroup (MG) libraries and the SCALE code package. The CASL VERA neutronics simulator MPACT does not include a gamma transport capability, which limits it to explicitly estimating local energy deposition from fission, neutron, and gamma slowing down and capture. Since the mean free path of gamma rays is typically much longer than that for the neutron, and the total gamma energy is about 10% to the total energy, the gamma-smeared power distribution is different from the fission power distribution. Explicit local energy deposition through neutron and gamma transport calculation is significantly important in multi-physics whole core simulation with thermal-hydraulic feedback. Therefore, the gamma transport capability should be incorporated into the CASL neutronics simulator MPACT. However, this task will be timeconsuming in developing the neutron induced gamma production and gamma cross section libraries. This study is to investigate an approximate model to estimate gammasmeared power distribution without performing any gamma transport calculation. A simple approximate gamma smearing model has been investigated based on the facts that pinwise gamma energy depositions are almost flat over a fuel assembly, and assembly-wise gamma energy deposition is proportional to kappa-fission energy deposition. The approximate gamma smearing model works well for single assembly cases, and can partly improve the gamma smeared power distribution for the whole core model. Although the power distributions can be improved by the approximate gamma smearing model, still there is an issue to explicitly obtain local energy deposition. A new simple approach or gamma transport/diffusion capability may need to be incorporated into MPACT to estimate local energy deposition for more robust multi-physics simulation.« less
NASA Astrophysics Data System (ADS)
Jidin, Razali; Othman, Bahari
2013-06-01
The lower Sg. Piah hydro-electric station is a river run-off hydro scheme with generators capable of generating 55MW of electricity. It is located 30km away from Sg. Siput, a small town in the state of Perak, Malaysia. The station has two turbines (Pelton) to harness energy from water that flow through a 7km tunnel from a small intake dam. The trait of a run-off river hydro station is small-reservoir that cannot store water for a long duration; therefore potential energy carried by the spillage will be wasted if the dam level is not appropriately regulated. To improve the station annual energy output, a new controller based on the computed river flow has been installed. The controller regulates the dam level with an algorithm based on the river flow derived indirectly from the intake-dam water level and other plant parameters. The controller has been able to maintain the dam at optimum water level and regulate the turbines to maximize the total generation output.
NASA Astrophysics Data System (ADS)
Clack, C.; MacDonald, A. E.; Wilczak, J. M.; Alexander, A.; Dunbar, A. D.; Xie, Y.; Picciano, P.; Paine, J.; Terry, L.; Marquis, M.
2015-12-01
The importance of weather-driven renewable energies for the United States energy portfolio is growing. The main perceived problems with weather-driven renewable energies are their intermittent nature, low power density, and high costs. The Cooperative Institute for the Research in Environmental Sciences at the University of Colorado collaborated with the Earth Systems Research Laboratory of the National Oceanic and Atmospheric Administration to construct a mathematical optimization of a reduced form of the US electric sector. Care was taken to retain salient features of the electric sector, while allowing for detailed weather and power data to be incorporated for wind and solar energies. The National Energy with Weather System (NEWS) simulator was created. With the NEWS simulator tests can be performed that are unique and insightful. The simulator can maintain the status quo and build out a system following costs or imposed targets for carbon dioxide emission reductions. It can find the least cost electric sector for each state, or find a national power system that incorporates vast amounts of variable generation. In the current presentation, we will focus on one of the most unique aspects of the NEWS simulator; the ability to specify a specific amount of wind and/or solar each hour for a three-year historical period for the least total cost. The simulator can find where to place wind and solar to reduce variability (ramping requirements for back-up generators). The amount of variable generation each hour is very different to an RPS type standard because the generators need to work in concert for long periods of time. The results indicate that for very similar costs the amount of back-up generation (natural gas or storage) can be reduced significantly.
Power enhancement of a μl-scale microbial fuel cells by surface roughness
NASA Astrophysics Data System (ADS)
Kim, Jihoon; Hwan Ko, Jin; Lee, Jaehyun; Jun Kim, Min; Byun, Doyoung
2014-06-01
In recent years, microbial fuel cells (MFCs) have gained much attention due to their potential to generate energy in a sustainable manner from living microorganisms. Research has shown that electrode design is a critical factor for MFCs power enhancement. In this study, we designed and fabricated MFCs energy-harvesting devices with living bacteria, and we investigated the effect of the surface roughness of the electrodes on power generation. In batch experiments of our MFCs, we found that the total power delivered could be enhanced using electrodes having rough surfaces with protruded micro-structures relative to that of electrodes with a flat surface. This was due to the delayed acidification resulting from the changes in bio-film formation between them.
NASA Astrophysics Data System (ADS)
Boulet, L.
Consideration is given to the possibility of generating sufficient energy at acceptable costs on earth to offset the need to build solar power satellite systems (SPS). Electricity usage, one of the basic driving forces of developed nations, grows with the population. Currently comprising 33 pct of the total world energy used, electricity is projected to grow to a 50-55 pct share in the 21st century. Future terrestrial electrical energy sources include carbon-based fuels, nuclear (fusion or fission), and the renewable solar technologies. Carbon-based fuel supplies can last until 2030 AD, about the same as fission plants with recycled fuel. Breeder reactors would stretch the nuclear fuels to the year 3000. Solar technologies offer more immediate solutions than fusion reactors and can produce 50 pct of the power available from the construction of the maximum number of nuclear power plants. The addition of SPS would further augment the total. Combinations of all the technologies are recommended, with local research for the most appropriate technology for each nation.
Numerical study of a permanent magnet linear generator for ship motion energy conversion
NASA Astrophysics Data System (ADS)
Mahmuddin, Faisal; Gunadin, Indar Chaerah; Akhir, Anshar Yaumil
2017-02-01
In order to harvest kinetic energy of a ship moving in waves, a permanent magnet linear generator is designed and simulated in the present study. For the sake of simplicity, only heave motion which will be considered in this preliminary study. The dimension of the generator is designed based on the dimension of the ship. Moreover, in order to designed an optimal design of rotor and stator, the average vertical displacement of heave motion is needed. For this purpose, a numerical method called New Strip Method (NSM) is employed to compute the motions of the ship. With NSM, the ship hull is divided into several strips and the hydrodynamics forces are computed on each strip. Moreover, because the ship is assumed to be slender, the total forces are obtained by integrating the force on each strip. After the motions can be determined, the optimal design of the generator is designed and simulated. The performance of the generator in terms of force, magnetic flux, losses, current and induced voltage which are the primary parameters of the linear generator performance, are evaluated using a finite element analysis software named Maxwell. From the study, a linear generator for converting heave motions is designed so that the produced power from the designed generator can be determined.
Partitioning of Electromagnetic Energy Inputs to the Thermosphere during Geomagnetic Disturbances
2012-06-01
boundary of a local flux tube volume is an equipotential . Figure 4 contains maps of Poynting flux normal to a 500 km altitude surface and maps of height...as a cell quantity throughout its computational volume, we are able to generate maps of the Poynting flux, ⃗ ⃗⃗⃗⃗⃗⃗ , on altitude surfaces at...the top of the thermosphere. We used separate modules to integrate the Poynting flux over this surface to compute the total electromagnetic energy
Microengineering Laser Plasma Interactions at Relativistic Intensities.
Jiang, S; Ji, L L; Audesirk, H; George, K M; Snyder, J; Krygier, A; Poole, P; Willis, C; Daskalova, R; Chowdhury, E; Lewis, N S; Schumacher, D W; Pukhov, A; Freeman, R R; Akli, K U
2016-02-26
We report on the first successful proof-of-principle experiment to manipulate laser-matter interactions on microscales using highly ordered Si microwire arrays. The interaction of a high-contrast short-pulse laser with a flat target via periodic Si microwires yields a substantial enhancement in both the total and cutoff energies of the produced electron beam. The self-generated electric and magnetic fields behave as an electromagnetic lens that confines and guides electrons between the microwires as they acquire relativistic energies via direct laser acceleration.
Microengineering Laser Plasma Interactions at Relativistic Intensities
NASA Astrophysics Data System (ADS)
Jiang, S.; Ji, L. L.; Audesirk, H.; George, K. M.; Snyder, J.; Krygier, A.; Poole, P.; Willis, C.; Daskalova, R.; Chowdhury, E.; Lewis, N. S.; Schumacher, D. W.; Pukhov, A.; Freeman, R. R.; Akli, K. U.
2016-02-01
We report on the first successful proof-of-principle experiment to manipulate laser-matter interactions on microscales using highly ordered Si microwire arrays. The interaction of a high-contrast short-pulse laser with a flat target via periodic Si microwires yields a substantial enhancement in both the total and cutoff energies of the produced electron beam. The self-generated electric and magnetic fields behave as an electromagnetic lens that confines and guides electrons between the microwires as they acquire relativistic energies via direct laser acceleration.
Silicon solar photovoltaic power stations
NASA Technical Reports Server (NTRS)
Chowaniec, C. R.; Ferber, R. R.; Pittman, P. F.; Marshall, B. W.
1977-01-01
Modular design of components and arrays, cost estimates for modules and support structures, and cost/performance analysis of a central solar photovoltaic power plant are discussed. Costs of collector/reflector arrays are judged the dominant element in the total capital investment. High-concentration solar tracking arrays are recommended as the most economic means for producing solar photovoltaic energy when solar cells costs are high ($500 per kW generated). Capital costs for power conditioning subsystem components are itemized and system busbar energy costs are discussed at length.
An Investigation of the Influence of Waves on Sediment Processes in Skagit Bay
2011-09-30
source term parameterizations common to most surface wave models, including wave generation by wind , energy dissipation from whitecapping, and...I. Total energy and peak frequency. Coastal Engineering (29), 47-78. Zijlema, M. Computation of wind -wave spectra in coastal waters with SWAN on unstructured grids Coastal Engineering, 2010, 57, 267-277 ...supply and wind on tidal flat sediment transport. It will be used to evaluate the capabilities of state-of-the-art open source sediment models and to
NASA Astrophysics Data System (ADS)
Cahyari, K.; Sarto; Syamsiah, S.; Prasetya, A.
2016-11-01
This research was meant to investigate performance of continuous stirred tank reactor (CSTR) as bioreactor for producing biohydrogen from melon waste through dark fermentation method. Melon waste are commonly generated from agricultural processing stages i.e. cultivation, post-harvesting, industrial processing, and transportation. It accounted for more than 50% of total harvested fruit. Feedstock of melon waste was fed regularly to CSTR according to organic loading rate at value 1.2 - 3.6 g VS/ (l.d). Optimum condition was achieved at OLR 2.4 g VS/ (l.d) with the highest total gas volume 196 ml STP. Implication of higher OLR value is reduction of total gas volume due to accumulation of acids (pH 4.0), and lower substrate volatile solid removal. In summary, application of this method might valorize melon waste and generates renewable energy sources.
ELECTRICAL LOAD ANTICIPATOR AND RECORDER
Werme, J.E.
1961-09-01
A system is described in which an indication of the prevailing energy consumption in an electrical power metering system and a projected power demand for one demand in terval is provided at selected increments of time within the demand interval. Each watt-hour meter in the system is provided with an impulse generator that generates two impulses for each revolution of the meter disc. In each demand interval, for example, one half-hour, of the metering system, the total impulses received from all of the meters are continuously totaled for each 5-minute interval and multiplied by a number from 6 to 1 depending upon which 5- minute interval the impulses were received. This value is added to the total pulses received in the intervals preceding the current 5-minute interval within the half-hour demand interval tc thereby provide an indication of the projected power demand every 5 minutes in the demand interval.
NASA Astrophysics Data System (ADS)
Dar, Zamiyad
The amount of wind energy in power systems is increasing at a significant rate. With this increased penetration, there are certain problems associated with the operation of windfarms which need careful attention. In the operations side, the wake effects of upstream wind turbines on downstream wind turbines can cause a reduction in the total generated power of a windfarm. On the market side, the fluctuation of real-time prices can make the operation of windfarms less profitable. Similarly, the intermittent nature of wind power prevents the windfarms from participating in the day-ahead and forward markets. On the system side, the volatile nature of wind speeds is also an obstacle for windfarms to provide frequency regulation to the system. In this thesis, we address these issues and optimize the operation of windfarms in power systems and deregulated electricity markets. First, the total power generation in a windfarm is maximized by using yaw angle of wind turbines as a control variable. We extend the existing wake models to include the effects of yaw misalignment and wake deflection of wind turbines. A numerical study is performed to find the optimal values of induction factor and yaw misalignment angle of wind turbines in a single row of a windfarm for achieving the maximum total power with wake effects. The numerical study shows that the maximum power is achieved by keeping the induction factor close to 1/3 and only changing the yaw angle to deflect the wake. We then propose a Dynamic Programming Framework (DPF) to maximize the total power production of a windfarm using yaw angle as the control variable. We compare the windfarm efficiency achieved with our DPF with the efficiency values obtained through greedy control strategy and induction factor optimization. We also extend our expressions to a windfarm with multiple rows and columns of turbines and perform simulations on the 3x3 and 4x4 grid topologies. Our results show that the optimal induction factor for most turbines is quite close to 1/3 and yaw angle acts as the dominant optimization variable. In the next part of this dissertation, a system comprising of a windfarm and energy storage operating in real-time electricity markets is studied. An Energy-balancing Threshold Price (ETP) policy is proposed to maximize the revenue of a windfarm with on-site storage. We propose and analyze a scheme for a windfarm to store or sell energy based on a threshold price. The threshold price is calculated based on long-term distributions of the electricity price and wind power generation processes, and is chosen so as to balance the energy flows in and out of the storage-equipped windfarm. It is also shown mathematically that the proposed policy is optimal in terms of the long-term revenue generated. Comparing it with the optimal policy that has knowledge of the future, we observe that the revenue obtained by the proposed ETP policy is approximately 90% of the maximum attainable revenue at a storage capacity of 10-15 times the power rating of the windfarm. The intermittent nature of wind power is a hindrance to the efficient participation of windfarms in the day-ahead and forward electricity markets. In this regard, a flexible forward contract is proposed in this dissertation which allows the windfarms to enter into a forward contract with flexible load with an option to deviate from the contracted amount of power. Using such a flexible contract would allow the windfarms to supply more or less than the contracted amount of power in case of unexpected wind conditions or real-time prices. We also propose models for forecasting wind power and real-time electricity prices. The comparison between the proposed contracting framework and a simple fixed contract (currently existing in the market) for different levels of flexibility and load shows that there is a net gain in windfarm revenues, if the transaction price of the two contracts are set equal. Lastly, we present and analyze distributed control schemes for frequency regulation in a smart grid using energy storage, wind generators, demand response and conventional generators while having no communication or data sharing between them. We also propose a novel control scheme for frequency support by energy storage in which the power output of energy storage changes proportionally with the reduction in its available energy. The application of the proposed control schemes indicates an improvement in system frequency characteristics, when there is a sudden net loss of generation.
Rooftop solar photovoltaic potential in cities: how scalable are assessment approaches?
NASA Astrophysics Data System (ADS)
Castellanos, Sergio; Sunter, Deborah A.; Kammen, Daniel M.
2017-12-01
Distributed photovoltaics (PV) have played a critical role in the deployment of solar energy, currently making up roughly half of the global PV installed capacity. However, there remains significant unused economically beneficial potential. Estimates of the total technical potential for rooftop PV systems in the United States calculate a generation comparable to approximately 40% of the 2016 total national electric-sector sales. To best take advantage of the rooftop PV potential, effective analytic tools that support deployment strategies and aggressive local, state, and national policies to reduce the soft cost of solar energy are vital. A key step is the low-cost automation of data analysis and business case presentation for structure-integrated solar energy. In this paper, the scalability and resolution of various methods to assess the urban rooftop PV potential are compared, concluding with suggestions for future work in bridging methodologies to better assist policy makers.
A new response matrix for a 6LiI scintillator BSS system
NASA Astrophysics Data System (ADS)
Lacerda, M. A. S.; Méndez-Villafañe, R.; Lorente, A.; Ibañez, S.; Gallego, E.; Vega-Carrillo, H. R.
2017-10-01
A new response matrix was calculated for a Bonner Sphere Spectrometer (BSS) with a 6 LiI(Eu) scintillator, using the Monte Carlo N-Particle radiation transport code MCNPX. Responses were calculated for 6 spheres and the bare detector, for energies varying from 1.059E(-9) MeV to 105.9 MeV, with 20 equal-log(E)-width bins per energy decade, totalizing 221 energy groups. A comparison was done among the responses obtained in this work and other published elsewhere, for the same detector model. The calculated response functions were inserted in the response input file of the MAXED code and used to unfold the total and direct neutron spectra generated by the 241Am-Be source of the Universidad Politécnica de Madrid (UPM). These spectra were compared with those obtained using the same unfolding code with the Mares and Schraube matrix response.
Microscopic Phase-Space Exploration Modeling of ^{258}Fm Spontaneous Fission.
Tanimura, Yusuke; Lacroix, Denis; Ayik, Sakir
2017-04-14
We show that the total kinetic energy (TKE) of nuclei after the spontaneous fission of ^{258}Fm can be well reproduced using simple assumptions on the quantum collective phase space explored by the nucleus after passing the fission barrier. Assuming energy conservation and phase-space exploration according to the stochastic mean-field approach, a set of initial densities is generated. Each density is then evolved in time using the nuclear time-dependent density-functional theory with pairing. This approach goes beyond the mean-field theory by allowing spontaneous symmetry breaking as well as a wider dynamical phase-space exploration leading to larger fluctuations in collective space. The total kinetic energy and mass distributions are calculated. New information on the fission process: fluctuations in scission time, strong correlation between TKE and collective deformation, as well as prescission particle emission, are obtained. We conclude that fluctuations of the TKE and mass are triggered by quantum fluctuations.
Impact of the 2017 Solar Eclipse on the Smart Grid
DOE Office of Scientific and Technical Information (OSTI.GOV)
Habte, Aron M; Reda, Ibrahim M; Andreas, Afshin M
With the increasing interest in using solar energy as a major contributor to the use of renewable generation, and with the focus on using smart grids to optimize the use of electrical energy based on demand and resources from different locations, the need arises to know the moons position in the sky with respect to the sun. When a solar eclipse occurs, the moon disk might totally or partially shade the sun disk, which can affect the irradiance level from the sun disk, consequently affecting a resource on the electric grid. The moons position can then provide smart grid usersmore » with information about how potential total or partial solar eclipses might affect different locations on the grid so that other resources on the grid can be directed to where they might be needed when such phenomena occurs. At least five solar eclipses occur yearly at different locations on Earth, they can last 3 hours or more depending on the location, and they can affect smart grid users. On August 21, 2017, a partial and full solar eclipse occurred in many locations in the United States, including at the National Renewable Energy Laboratory in Golden, Colorado. Solar irradiance measurements during the eclipse were compared to the data generated by a model for validation at eight locations.« less
Nair, Ramkumar B; Kabir, Maryam M; Lennartsson, Patrik R; Taherzadeh, Mohammad J; Horváth, Ilona Sárvári
2018-01-01
Integration of wheat straw for a biorefinery-based energy generation process by producing ethanol and biogas together with the production of high-protein fungal biomass (suitable for feed application) was the main focus of the present study. An edible ascomycete fungal strain Neurospora intermedia was used for the ethanol fermentation and subsequent biomass production from dilute phosphoric acid (0.7 to 1.2% w/v) pretreated wheat straw. At optimum pretreatment conditions, an ethanol yield of 84 to 90% of the theoretical maximum, based on glucan content of substrate straw, was observed from fungal fermentation post the enzymatic hydrolysis process. The biogas production from the pretreated straw slurry showed an improved methane yield potential up to 162% increase, as compared to that of the untreated straw. Additional biogas production, using the syrup, a waste stream obtained post the ethanol fermentation, resulted in a combined total energy output of 15.8 MJ/kg wheat straw. Moreover, using thin stillage (a waste stream from the first-generation wheat-based ethanol process) as a co-substrate to the biogas process resulted in an additional increase by about 14 to 27% in the total energy output as compared to using only wheat straw-based substrates. ᅟ.
Future Market Share of Space Solar Electric Power Under Open Competition
NASA Astrophysics Data System (ADS)
Smith, S. J.; Mahasenan, N.; Clarke, J. F.; Edmonds, J. A.
2002-01-01
This paper assesses the value of Space Solar Power deployed under market competition with a full suite of alternative energy technologies over the 21st century. Our approach is to analyze the future energy system under a number of different scenarios that span a wide range of possible future demographic, socio-economic, and technological developments. Scenarios both with, and without, carbon dioxide concentration stabilization policies are considered. We use the comprehensive set of scenarios created for the Intergovernmental Panel on Climate Change Special Report on Emissions Scenarios (Nakicenovic and Swart 2000). The focus of our analysis will be the cost of electric generation. Cost is particularly important when considering electric generation since the type of generation is, from a practical point of view, largely irrelevant to the end-user. This means that different electricity generation technologies must compete on the basis of price. It is important to note, however, that even a technology that is more expensive than average can contribute to the overall generation mix due to geographical and economic heterogeneity (Clarke and Edmonds 1993). This type of competition is a central assumption of the modeling approach used here. Our analysis suggests that, under conditions of full competition of all available technologies, Space Solar Power at 7 cents per kW-hr could comprise 5-10% of global electric generation by the end of the century, with a global total generation of 10,000 TW-hr. The generation share of Space Solar Power is limited due to competition with lower-cost nuclear, biomass, and terrestrial solar PV and wind. The imposition of a carbon constraint does not significantly increase the total amount of power generated by Space Solar Power in cases where a full range of advanced electric generation technologies are also available. Potential constraints on the availability of these other electric generation options can increase the amount of electricity generated by Space Solar Power. In agreement with previous work on this subject, we note that launch costs are a significant impediment for the widespread implementation of Space Solar Power. KEY WORDS: space satellite power, advanced electric generation, electricity price, climate change
NASA Technical Reports Server (NTRS)
Ho, D.; Sobon, L. E.
1979-01-01
A conceptual design is presented for fiberglass production systems in both lunar and space environments. The raw material, of lunar origin, will be plagioclase concentrate, high silica content slag, and calcium oxide. Glass will be melted by solar energy. The multifurnace in the lunar plant and the spinning cylinder in the space plant are unique design features. Furnace design appears to be the most critical element in optimizing system performance. A conservative estimate of the total power generated by solar concentrators is 1880 kW; the mass of both plants is 120 tons. The systems will reproduce about 90 times their total mass in fiberglass in 1 year. A new design concept would be necessary if glass rods were produced in space.
Skylight energy performance and design optimization
DOE Office of Scientific and Technical Information (OSTI.GOV)
Arasteh, D.; Johnson, R.; Selkowitz, S.
1984-02-01
Proper skylight utilization can significantly lower energy requirements and peak electrical loads for space conditioning and lighting in commercial buildings. In this study we systematically explore the energy effects of skylight systems in a prototypical office building and examine the savings from daylighting. The DOE-2.1B energy analysis computer program with its newly incorporated daylighting algorithms was used to generate more than 2000 parametric simulations for seven US climates. The parameters varied include skylight-to-roof ratio, shading coefficient, visible transmittance, skylight well light loss, electric lighting power density, roof heat transfer coefficient, and type of electric lighting control. For specific climates wemore » identify roof/skylight characteristics that minimize total energy or peak electrical load requirements.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Shen, Bo; Lu, Hongyou; Price, Lynn K.
In the U.S., energy consumption by steam and process heat combined accounts for over 50% of the total energy use from industrial systems (see Figure 1). The use of boilers, process heaters, and furnaces for generating steam and heat in industrial facilities, commercial settings, and institutions consumes significant amounts of energy and is one of major sources of hazardous air pollutants, which contribute significantly to local pollution and global climate change. To address the energy and environmental challenges caused by boiler systems in the U.S., the country has taken a series of actions to reduce emissions from industrial, commercial andmore » institutional boilers, improve the efficiency of steam systems, replace coal with cleaner energy resources, and promote the wider use of combined heat and power (CHP).« less
Nucleon and deuteron scattering cross sections from 25 MV/Nucleon to 22.5 GeV/Nucleon
NASA Technical Reports Server (NTRS)
Townsend, L. W.; Wilson, J. W.; Bidasaria, H. B.
1983-01-01
Within the context of a double-folding optical potential approximation to the exact nucleus-nucleus multiple-scattering series, eikonal scattering theory is used to generate tables of nucleon and deuteron total and absorption cross sections at kinetic energies between 25 MeV/nucleon and 22.5 GeV/nucleon for use in cosmic-ray transport and shielding studies. Comparisons of predictions for nucleon-nucleus and deuteron-nucleus absorption and total cross sections with experimental data are also made.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
1994-09-01
The Department of Energy`s (DOE`s) planning for the disposal of greater-than-Class C low-level radioactive waste (GTCC LLW) requires characterization of the waste. This report estimates volumes, radionuclide activities, and waste forms of GTCC LLW to the year 2035. It groups the waste into four categories, representative of the type of generator or holder of the waste: Nuclear Utilities, Sealed Sources, DOE-Held, and Other Generator. GTCC LLW includes activated metals (activation hardware from reactor operation and decommissioning), process wastes (i.e., resins, filters, etc.), sealed sources, and other wastes routinely generated by users of radioactive material. Estimates reflect the possible effect thatmore » packaging and concentration averaging may have on the total volume of GTCC LLW. Possible GTCC mixed LLW is also addressed. Nuclear utilities will probably generate the largest future volume of GTCC LLW with 65--83% of the total volume. The other generators will generate 17--23% of the waste volume, while GTCC sealed sources are expected to contribute 1--12%. A legal review of DOE`s obligations indicates that the current DOE-Held wastes described in this report will not require management as GTCC LLW because of the contractual circumstances under which they were accepted for storage. This report concludes that the volume of GTCC LLW should not pose a significant management problem from a scientific or technical standpoint. The projected volume is small enough to indicate that a dedicated GTCC LLW disposal facility may not be justified. Instead, co-disposal with other waste types is being considered as an option.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kelley, Christopher Lee; Maniaci, David Charles; Resor, Brian R.
2015-10-01
The total energy produced by a wind farm depends on the complex interaction of many wind turbines operating in proximity with the turbulent atmosphere. Sometimes, the unsteady forces associated with wind negatively influence power production, causing damage and increasing the cost of producing energy associated with wind power. Wakes and the motion of air generated by rotating blades need to be better understood. Predicting wakes and other wind forces could lead to more effective wind turbine designs and farm layouts, thereby reducing the cost of energy, allowing the United States to increase the installed capacity of wind energy. The Windmore » Energy Technologies Department at Sandia has collaborated with the University of Minnesota to simulate the interaction of multiple wind turbines. By combining the validated, large-eddy simulation code with Sandia’s HPC capability, this consortium has improved its ability to predict unsteady forces and the electrical power generated by an array of wind turbines. The array of wind turbines simulated were specifically those at the Sandia Scaled Wind Farm Testbed (SWiFT) site which aided the design of new wind turbine blades being manufactured as part of the National Rotor Testbed project with the Department of Energy.« less
Increasing the percentage of renewable energy in the Southwestern United States
USDA-ARS?s Scientific Manuscript database
An analysis was performed on the states in the Southwestern United States to determine methods to increase the proportion of wind and solar generated electricity in those states to levels as high as 40% of total electricity used. This analysis was performed by comparing the monthly and diurnal elect...
Radio wave heating of the corona and electron precipitation during flares
NASA Technical Reports Server (NTRS)
Melrose, D. B.; Dulk, G. A.
1982-01-01
Electron-cyclotron masers, excited while energy release is occurring in a flaring magnetic loop, are likely to generate extremely intense radiation at decimeter wavelengths. The energy in the radiation can be comparable with that in the electrons associated with hard X-ray bursts, i.e., a significant fraction of the total energy in the flare. Essentially all of the radio energy is likely to be reabsorbed by gyroresonance absorption, either near the emitting region or at some distance away in neighboring loops. Enhanced diffusion of fast electrons caused by the maser can lead to precipitation at the maximum possible rate, and hence account for hard X-ray emission from the footpoints of the magnetic loops.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Slauch, Ian M.; Deceglie, Michael G.; Silverman, Timothy J.
Waste heat generated during daytime operation of a solar module will raise its temperature and reduce cell efficiency. In addition to thermalization and carrier recombination, one major source of excess heat in modules is the parasitic absorption of light with sub-bandgap energy. Parasitic absorption can be prevented if sub-bandgap radiation is reflected away from the module. We report on the design considerations and projected changes to module energy yield for photonic reflectors capable of reflecting a portion of sub-bandgap radiation while maintaining or improving transmission of light with energy greater than the semiconductor bandgap. Using a previously developed, self-consistent opto-electro-thermalmore » finite-element simulation, we calculate the total additional energy generated by a module, including various photonic reflectors, and decompose these benefits into thermal and optical effects. We show that the greatest total energy yield improvement comes from photonic mirrors designed for the outside of the glass, but that mirrors placed between the glass and the encapsulant can have significant thermal benefit. We then show that optimal photonic mirror design requires consideration of all angles of incidence, despite unequal amounts of radiation arriving at each angle. We find that optimized photonic mirrors will be omnidirectional in the sense that they have beneficial performance, regardless of the angle of incidence of radiation. By fulfilling these criteria, photonic mirrors can be used at different geographic locations or different tilt angles than their original optimization conditions with only marginal changes in performance. We show designs that improve energy output in Golden, Colorado by 3.7% over a full year. This work demonstrates the importance of considering real-world irradiance and weather conditions when designing optical structures for solar applications.« less
Slauch, Ian M.; Deceglie, Michael G.; Silverman, Timothy J.; ...
2018-03-02
Waste heat generated during daytime operation of a solar module will raise its temperature and reduce cell efficiency. In addition to thermalization and carrier recombination, one major source of excess heat in modules is the parasitic absorption of light with sub-bandgap energy. Parasitic absorption can be prevented if sub-bandgap radiation is reflected away from the module. We report on the design considerations and projected changes to module energy yield for photonic reflectors capable of reflecting a portion of sub-bandgap radiation while maintaining or improving transmission of light with energy greater than the semiconductor bandgap. Using a previously developed, self-consistent opto-electro-thermalmore » finite-element simulation, we calculate the total additional energy generated by a module, including various photonic reflectors, and decompose these benefits into thermal and optical effects. We show that the greatest total energy yield improvement comes from photonic mirrors designed for the outside of the glass, but that mirrors placed between the glass and the encapsulant can have significant thermal benefit. We then show that optimal photonic mirror design requires consideration of all angles of incidence, despite unequal amounts of radiation arriving at each angle. We find that optimized photonic mirrors will be omnidirectional in the sense that they have beneficial performance, regardless of the angle of incidence of radiation. By fulfilling these criteria, photonic mirrors can be used at different geographic locations or different tilt angles than their original optimization conditions with only marginal changes in performance. We show designs that improve energy output in Golden, Colorado by 3.7% over a full year. This work demonstrates the importance of considering real-world irradiance and weather conditions when designing optical structures for solar applications.« less
The contribution of low-energy protons to the total on-orbit SEU rate
Dodds, Nathaniel Anson; Martinez, Marino J.; Dodd, Paul E.; ...
2015-11-10
Low- and high-energy proton experimental data and error rate predictions are presented for many bulk Si and SOI circuits from the 20-90 nm technology nodes to quantify how much low-energy protons (LEPs) can contribute to the total on-orbit single-event upset (SEU) rate. Every effort was made to predict LEP error rates that are conservatively high; even secondary protons generated in the spacecraft shielding have been included in the analysis. Across all the environments and circuits investigated, and when operating within 10% of the nominal operating voltage, LEPs were found to increase the total SEU rate to up to 4.3 timesmore » as high as it would have been in the absence of LEPs. Therefore, the best approach to account for LEP effects may be to calculate the total error rate from high-energy protons and heavy ions, and then multiply it by a safety margin of 5. If that error rate can be tolerated then our findings suggest that it is justified to waive LEP tests in certain situations. Trends were observed in the LEP angular responses of the circuits tested. As a result, grazing angles were the worst case for the SOI circuits, whereas the worst-case angle was at or near normal incidence for the bulk circuits.« less
Kneifel, Joshua; O'Rear, Eric; Webb, David; O'Fallon, Cheyney
2018-02-01
To conduct a more complete analysis of low-energy and net-zero energy buildings that considers both the operating and embodied energy/emissions, members of the building community look to life-cycle assessment (LCA) methods. This paper examines differences in the relative impacts of cost-optimal energy efficiency measure combinations depicting residential buildings up to and beyond net-zero energy consumption on operating and embodied flows using data from the Building Industry Reporting and Design for Sustainability (BIRDS) Low-Energy Residential Database. Results indicate that net-zero performance leads to a large increase in embodied flows (over 40%) that offsets some of the reductions in operational flows, but overall life-cycle flows are still reduced by over 60% relative to the state energy code. Overall, building designs beyond net-zero performance can partially offset embodied flows with negative operational flows by replacing traditional electricity generation with solar production, but would require an additional 8.34 kW (18.54 kW in total) of due south facing solar PV to reach net-zero total life-cycle flows. Such a system would meet over 239% of operational consumption of the most energy efficient design considered in this study and over 116% of a state code-compliant building design in its initial year of operation.
NASA Astrophysics Data System (ADS)
Klir, D.; Shishlov, A. V.; Kokshenev, V. A.; Kubes, P.; Labetsky, A. Yu; Rezac, K.; Cherdizov, R. K.; Cikhardt, J.; Cikhardtova, B.; Dudkin, G. N.; Fursov, F. I.; Garapatsky, A. A.; Kovalchuk, B. M.; Kravarik, J.; Kurmaev, N. E.; Orcikova, H.; Padalko, V. N.; Ratakhin, N. A.; Sila, O.; Turek, K.; Varlachev, V. A.
2015-04-01
Z-pinch experiments with deuterium gas puffs have been carried out on the GIT-12 generator at 3 MA currents. Recently, a novel configuration of a deuterium gas-puff z-pinch was used to accelerate deuterons and to generate fast neutrons. In order to form a homogeneous, uniformly conducting layer at a large initial radius, an inner deuterium gas puff was surrounded by an outer hollow cylindrical plasma shell. The plasma shell consisting of hydrogen and carbon ions was formed at the diameter of 350 mm by 48 plasma guns. A linear mass of the plasma shell was about 5 µg cm-1 whereas a total linear mass of deuterium gas in single or double shell gas puffs was about 100 µg cm-1. The implosion lasted 700 ns and seemed to be stable up to a 5 mm radius. During stagnation, m = 0 instabilities became more pronounced. When a disruption of necks occurred, the plasma impedance reached 0.4 Ω and high energy (>2 MeV) bremsstrahlung radiation together with high energy deuterons were produced. Maximum neutron energies of 33 MeV were observed by axial time-of-flight detectors. The observed neutron spectra could be explained by a suprathermal distribution of deuterons with a high energy tail f≤ft({{E}\\text{d}}\\right)\\propto E\\text{d}-(1.8+/- 0.2) . Neutron yields reached 3.6 × 1012 at a 2.7 MA current. A high neutron production efficiency of 6 × 107 neutrons per one joule of plasma energy resulted from the generation of high energy deuterons and from their magnetization inside plasmas.
Development and Evaluation of Control System for Microgrid Supplying Heat and Electricity
NASA Astrophysics Data System (ADS)
Kojima, Yasuhiro; Koshio, Masanobu; Nakamura, Shizuka
Photovoltaic (PV) and Wind Turbine (WT) generation systems are expected to offer solutions to reduce green house gases and become more widely used in the future. However, the chief technical drawback of using these kinds of weather-dependent generators is the difficulty of forecasting their output, which can have negative impacts on commercial grids if a large number of them are introduced. Thus, this problem may hinder the wider application of PV and WT generation systems. The Regional Power Grid with Renewable Energy Resources Project was launched to seek a solution to this problem. The scope of the project is to develop, operate, and evaluate a Dispersed Renewable Energy Supply System with the ability to adapt the total energy output in response to changes in weather and demand. Such a system would reduce the impact that PV and WT generation systems have on commercial grids and allow the interconnection of more Dispersed Energy Resources (DER). In other words, the main objective of this project is to demonstrate an integrated energy management system, or a type of microgrid [1], as a new way of introducing DERs. The system has been in operation since October 2005 and will continue operation until March 2008. Through the project period, the data on power quality, system efficiency, operation cost, and environmental burden will be gathered and a cost-benefit analysis of the system will be undertaken. In this paper, firstly we introduce the concept of microgrid for reducing negative impact of natural energy, and secondly illustrate the structure of electric and thermal supply control system for Microgrid, especially for the Hachinohe demonstration project. The control system consists of four stages; weekly operation planning, economic dispatching control, tie-line control and local frequency control. And finally demonstration results and evaluation results are shown.
Reductions in greenhouse gas (GHG) generation and energy consumption in wastewater treatment plants.
Yerushalmi, L; Ashrafi, O; Haghighat, F
2013-01-01
Greenhouse gas (GHG) emission and energy consumption by on-site and off-site sources were estimated in two different wastewater treatment plants that used physical-chemical or biological processes for the removal of contaminants, and an anaerobic digester for sludge treatment. Physical-chemical treatment processes were used in the treatment plant of a locomotive repair factory that processed wastewater at 842 kg chemical oxygen demand per day. Approximately 80% of the total GHG emission was related to fossil fuel consumption for energy production. The emission of GHG was reduced by 14.5% with the recovery of biogas that was generated in the anaerobic digester and its further use as an energy source, replacing fossil fuels. The examined biological treatment system used three alternative process designs for the treatment of effluents from pulp and paper mills that processed wastewater at 2,000 kg biochemical oxygen demand per day. The three designs used aerobic, anaerobic, or hybrid aerobic/anaerobic biological processes for the removal of carbonaceous contaminants, and nitrification/denitrification processes for nitrogen removal. Without the recovery and use of biogas, the aerobic, anaerobic, and hybrid treatment systems generated 3,346, 6,554 and 7,056 kg CO(2)-equivalent/day, respectively, while the generated GHG was reduced to 3,152, 6,051, and 6,541 kg CO(2)-equivalent/day with biogas recovery. The recovery and use of biogas was shown to satisfy and exceed the energy needs of the three examined treatment plants. The reduction of operating temperature of the anaerobic digester and anaerobic reactor by 10°C reduced energy demands of the treatment plants by 35.1, 70.6 and 62.9% in the three examined treatment systems, respectively.
Simplified modeling of blast waves from metalized heterogeneous explosives
NASA Astrophysics Data System (ADS)
Zarei, Z.; Frost, D. L.
2011-09-01
The detonation of a metalized explosive generates a complex multiphase flow field. Modeling the subsequent propagation of the blast front requires a detailed knowledge of the metal particle dynamics and reaction rate. Given the uncertainties in modeling these phenomena, a much simpler, 1D compressible flow model is used to illustrate the general effects of secondary energy release due to particle reaction on the blast front properties. If the total energy release is held constant, the blast pressure and impulse are primarily dependent on the following parameters: the proportion of secondary energy released due to afterburning, the rate of energy release, the location the secondary energy release begins, and the range over which it occurs. Releasing the total energy over a longer time period in general reduces the peak blast overpressure at a given distance. However, secondary energy release reduces the rate of decay of the shock pressure, increases the local gas temperature and hence increases the velocity of the secondary shock front. As a result, for certain values of the above parameters, the peak blast impulse may be increased by a factor of about two in a region near the charge. The largest augmentation to the near-field peak impulse results when the secondary energy is released immediately behind the shock front rather than uniformly within the combustion products.
Warm Body Temperature Facilitates Energy Efficient Cortical Action Potentials
Yu, Yuguo; Hill, Adam P.; McCormick, David A.
2012-01-01
The energy efficiency of neural signal transmission is important not only as a limiting factor in brain architecture, but it also influences the interpretation of functional brain imaging signals. Action potential generation in mammalian, versus invertebrate, axons is remarkably energy efficient. Here we demonstrate that this increase in energy efficiency is due largely to a warmer body temperature. Increases in temperature result in an exponential increase in energy efficiency for single action potentials by increasing the rate of Na+ channel inactivation, resulting in a marked reduction in overlap of the inward Na+, and outward K+, currents and a shortening of action potential duration. This increase in single spike efficiency is, however, counterbalanced by a temperature-dependent decrease in the amplitude and duration of the spike afterhyperpolarization, resulting in a nonlinear increase in the spike firing rate, particularly at temperatures above approximately 35°C. Interestingly, the total energy cost, as measured by the multiplication of total Na+ entry per spike and average firing rate in response to a constant input, reaches a global minimum between 37–42°C. Our results indicate that increases in temperature result in an unexpected increase in energy efficiency, especially near normal body temperature, thus allowing the brain to utilize an energy efficient neural code. PMID:22511855
Conflicting hydropower development and aquatic ecosystem conservation in Bhutan
NASA Astrophysics Data System (ADS)
Wi, S.; Yang, Y. C. E.
2017-12-01
Hydropower is one of the clean energy sources that many Himalayan countries are eager to develop to solve their domestic energy deficit issue such as India, Nepal and Pakistan. Like other Himalayan countries, Bhutan also has a great potential for hydropower development. However, Bhutan is one of few countries that has a domestic energy surplus and export its hydropower generation to neighboring countries (mainly to India). Exporting hydropower is one of the major economic sources in Bhutan. However, constructions of dams and reservoirs for hydropower development inevitably involve habitat fragmentation, causing a conflict of interest with the pursuit of value in aquatic ecosystem conservation. The objectives of this study is to 1) develop a distributed hydrologic model with snow and glacier module to simulate the hydrologic regimes of seven major watersheds in Bhutan; 2) apply the hydrologic model to compute hydropower generation for all existing and potential dams; 3) evaluate cascade impacts of each individual dam on downstream regions by employing three hydro-ecological indicators: the River Connectivity Index (RCI), Dendritic Connectivity Index (DCI), total affected river stretch (ARS), and 4) analyze the tradeoffs between hydropower generation and river connectivity at the national scale by means of a multiple objective genetic algorithm. Modeling results of three Pareto Fronts between ecological indicators and hydropower generation accompany with future energy export targets from the government can inform dam selections that maximizing hydropower generation while minimizing the impact on the aquatic ecosystem (Figure 1a). The impacts of climate change on these Pareto front are also explored to identify robust dam selection under changing temperature and precipitation (Figure 1b).
Smart Energy Management of Multiple Full Cell Powered Applications
DOE Office of Scientific and Technical Information (OSTI.GOV)
MOhammad S. Alam
2007-04-23
In this research project the University of South Alabama research team has been investigating smart energy management and control of multiple fuel cell power sources when subjected to varying demands of electrical and thermal loads together with demands of hydrogen production. This research has focused on finding the optimal schedule of the multiple fuel cell power plants in terms of electric, thermal and hydrogen energy. The optimal schedule is expected to yield the lowest operating cost. Our team is also investigating the possibility of generating hydrogen using photoelectrochemical (PEC) solar cells through finding materials for efficient light harvesting photoanodes. Themore » goal is to develop an efficient and cost effective PEC solar cell system for direct electrolysis of water. In addition, models for hydrogen production, purification, and storage will be developed. The results obtained and the data collected will be then used to develop a smart energy management algorithm whose function is to maximize energy conservation within a managed set of appliances, thereby lowering O/M costs of the Fuel Cell power plant (FCPP), and allowing more hydrogen generation opportunities. The Smart Energy Management and Control (SEMaC) software, developed earlier, controls electrical loads in an individual home to achieve load management objectives such that the total power consumption of a typical residential home remains below the available power generated from a fuel cell. In this project, the research team will leverage the SEMaC algorithm developed earlier to create a neighborhood level control system.« less
NASA Astrophysics Data System (ADS)
Pizzolato, R.
2017-12-01
Can skyscrapers become carbon neutral using wind that flows around them to power wind turbines? I say YES! To test this idea, I constructed a venturi to capture wind flowing around a skyscraper by applying Bernoulli's Principle and the Venturi Effect to power vertical axis wind turbines (VAWT) to generate electricity. The model was constructed from polycarbonate. Turbine blades (45°&60°) carved from balsa wood with square edges, airfoils, and trailing edge tubercles (Humpback whales-biomimicry) were tested in a wind tunnel. Output was measured using Vernier's Logger Pro 3.12 software, energy and wind sensors. Voltage (mV), current (mA), power (mW) and total energy (mJ) produced at winds speeds of 3.9, 5, 7.5 and 10 m/s were recorded. 10 trials were performed for each blade angle and each blade design for a total of 240 trials. Trials were 100 seconds long and recorded at a rate of 10 measurements/second. The blades that showed the largest %Δ in total average energy output (mJ) were the 60° airfoil blades w/ tubercles on the trailing edge (20,490 mJ) when compared to 60° square edged blades (7,021 mJ). The trend of the data showed that the airfoils w/tubercles (45° & 60°) outperformed all the other blade designs at wind speeds of 7.5 m/s and 10 m/s. Also, the 45° airfoil w/tubercles produced the highest output of 25,136 mJ! This was possibly due to the improved aerodynamics of the tubercle blades which led to improvements in lift and a reduction in drag. The data shows that turbine blades that incorporate biomimicry in their design result in more efficient power output. Through biomimicry, it is possible to efficiently generate electricity with a skyscraper and reduce our dependence upon fossil fuels!
NASA Astrophysics Data System (ADS)
Heredia, Cristian Alonso
The National Academy of Engineers named affordable solar energy as one of the grand challenges for the twenty-first century. Even in sunniest U.S. locations, without subsidies, home generation is still cost prohibitive. To address the cost of solar energy, we investigated intrinsic silicon as a low emissivity selective absorber. We wanted to determine the emissivity of intrinsic silicon at elevated temperatures. At elevated temperatures, a selective absorber coupled to a heat engine could efficiently generate electrical power. Photothermal efficiency depends on the absorber's emissivity. I analyzed total hemispherical emissivity for graphite and intrinsic silicon using a thermal decay method inside a thermal isolation chamber. The results show low emissivity values for intrinsic silicon. Consequently, for temperatures less than 300 °C, intrinsic silicon has a small emissivity (0.16). This small value is in agreement with doped silicon experiments. However, unlike doped silicon, at elevated temperatures of 600 °C, intrinsic silicon emissivity values remain low (0.33). Our analysis suggests intrinsic silicon could convert more solar power into heat than an ideal blackbody. Specifically, the harvested heat could drive a heat engine for efficient power generation. Thus, a cost-effective electrical generating system can operate with a small land footprint using earth abundant silicon.
Product reliability and thin-film photovoltaics
NASA Astrophysics Data System (ADS)
Gaston, Ryan; Feist, Rebekah; Yeung, Simon; Hus, Mike; Bernius, Mark; Langlois, Marc; Bury, Scott; Granata, Jennifer; Quintana, Michael; Carlson, Carl; Sarakakis, Georgios; Ogden, Douglas; Mettas, Adamantios
2009-08-01
Despite significant growth in photovoltaics (PV) over the last few years, only approximately 1.07 billion kWhr of electricity is estimated to have been generated from PV in the US during 2008, or 0.27% of total electrical generation. PV market penetration is set for a paradigm shift, as fluctuating hydrocarbon prices and an acknowledgement of the environmental impacts associated with their use, combined with breakthrough new PV technologies, such as thin-film and BIPV, are driving the cost of energy generated with PV to parity or cost advantage versus more traditional forms of energy generation. In addition to reaching cost parity with grid supplied power, a key to the long-term success of PV as a viable energy alternative is the reliability of systems in the field. New technologies may or may not have the same failure modes as previous technologies. Reliability testing and product lifetime issues continue to be one of the key bottlenecks in the rapid commercialization of PV technologies today. In this paper, we highlight the critical need for moving away from relying on traditional qualification and safety tests as a measure of reliability and focus instead on designing for reliability and its integration into the product development process. A drive towards quantitative predictive accelerated testing is emphasized and an industrial collaboration model addressing reliability challenges is proposed.
Laser Induced Hydrogen Generation from Coal in Water
NASA Astrophysics Data System (ADS)
Seyitliyev, Dovletgeldi; Kholikov, Khomidkhodzha; Er, Ali
We report an alternative way of obtaining hydrogen using nanosecond laser pulses and various ranks of coal and coke. SEM-EDS analysis shows the atomic concentrations of elements on each of the powders which also is in good agreement with calorimeter analysis. Coal and coke powders were irradiated with 1064nm IR and 532 nm green Nd:YAG pulsed laser beam for 45 minutes. The volume of the total gas generated after irradiation of each rank was measured using the water displacement method. The amount of gas generated increased when using 532 nm compared to 1064 nm. Post-irradiation SEM images show structural differences with samples before irradiation. The amount of gas generation with respect to laser energy density shows nonlinear correlation. Generated gas concentrations were then analyzed using gas chromatography (GC). Hydrogen and carbon monoxide were the two most highly generated gases, and the efficiency of each rank of coal was determined by analyzing the hydrogen to carbon monoxide ratio. The highest efficiency rank was anthracite, with hydrogen to carbon monoxide ratio of 1.4. GC analysis also showed that the maximum hydrogen generation occurs at 100 mJ/pulse laser energy. The efficiency of each rank of coal was observed to correlate with carbon content. American Chemical Society Petroleum Research Fund.
Energy scavenging strain absorber: application to kinetic dielectric elastomer generator
NASA Astrophysics Data System (ADS)
Jean-Mistral, C.; Beaune, M.; Vu-Cong, T.; Sylvestre, A.
2014-03-01
Dielectric elastomer generators (DEGs) are light, compliant, silent energy scavengers. They can easily be incorporated into clothing where they could scavenge energy from the human kinetic movements for biomedical applications. Nevertheless, scavengers based on dielectric elastomers are soft electrostatic generators requiring a high voltage source to polarize them and high external strain, which constitutes the two major disadvantages of these transducers. We propose here a complete structure made up of a strain absorber, a DEG and a simple electronic power circuit. This new structure looks like a patch, can be attached on human's wear and located on the chest, knee, elbow… Our original strain absorber, inspired from a sailing boat winch, is able to heighten the external available strain with a minimal factor of 2. The DEG is made of silicone Danfoss Polypower and it has a total area of 6cm per 2.5cm sustaining a maximal strain of 50% at 1Hz. A complete electromechanical analytical model was developed for the DEG associated to this strain absorber. With a poling voltage of 800V, a scavenged energy of 0.57mJ per cycle is achieved with our complete structure. The performance of the DEG can further be improved by enhancing the imposed strain, by designing a stack structure, by using a dielectric elastomer with high dielectric permittivity.
Yodkhum, Sanwasan; Sampattagul, Sate; Gheewala, Shabbir H
2018-04-17
Rice cultivation and energy use for rice production can produce the environmental impacts, especially related to greenhouse gas (GHG) emissions. Also, rice straw open burning by farmers generally practiced after harvesting stage in Thailand for removing the residues in the rice field is associated with emissions of air pollutants, especially particulate matter formation that affects human health and global climate. This study assessed the environmental burdens, consisting of GHG emissions, energy use, and particulate matter formation (PM10), from rice cultivation in Thailand by life cycle assessment (LCA) and compared the environmental burdens of rice straw management scenarios: open burning, incorporation into soil, and direct combustion for electricity generation. The data were collected from the rice production cooperative in Chiang Mai province, northern Thailand, via onsite records and face-to-face questionnaires in 2016. The environmental impacts were evaluated from cradle-to-farm gate. The results showed that the total GHG emissions were 0.64 kg CO 2 -eq per kilogram of paddy rice, the total energy use was 1.80 MJ per kilogram of paddy rice and the PM10 emissions were 0.42 g PM10-eq per kilogram of paddy rice. The results of rice straw management scenarios showed that rice straw open burning had the highest GHG and PM10 emissions. However, rice straw utilization by incorporation into soil and direct combustion for electricity generation could reduce these impacts substantially.
Comparison of two U.S. power-plant carbon dioxide emissions data sets
Ackerman, K.V.; Sundquist, E.T.
2008-01-01
Estimates of fossil-fuel CO2 emissions are needed to address a variety of climate-change mitigation concerns over a broad range of spatial and temporal scales. We compared two data sets that report power-plant CO 2 emissions in the conterminous U.S. for 2004, the most recent year reported in both data sets. The data sets were obtained from the Department of Energy's Energy Information Administration (EIA) and the Environmental Protection Agency's eGRID database. Conterminous U.S. total emissions computed from the data sets differed by 3.5% for total plant emissions (electricity plus useful thermal output) and 2.3% for electricity generation only. These differences are well within previous estimates of uncertainty in annual U.S. fossil-fuel emissions. However, the corresponding average absolute differences between estimates of emissions from individual power plants were much larger, 16.9% and 25.3%, respectively. By statistical analysis, we identified several potential sources of differences between EIA and eGRID estimates for individual plants. Estimates that are based partly or entirely on monitoring of stack gases (reported by eGRID only) differed significantly from estimates based on fuel consumption (as reported by EIA). Differences in accounting methods appear to explain differences in estimates for emissions from electricity generation from combined heat and power plants, and for total and electricity generation emissions from plants that burn nonconventional fuels (e.g., biomass). Our analysis suggests the need for care in utilizing emissions data from individual power plants, and the need for transparency in documenting the accounting and monitoring methods used to estimate emissions.
Prediction equation for estimating total daily energy requirements of special operations personnel.
Barringer, N D; Pasiakos, S M; McClung, H L; Crombie, A P; Margolis, L M
2018-01-01
Special Operations Forces (SOF) engage in a variety of military tasks with many producing high energy expenditures, leading to undesired energy deficits and loss of body mass. Therefore, the ability to accurately estimate daily energy requirements would be useful for accurate logistical planning. Generate a predictive equation estimating energy requirements of SOF. Retrospective analysis of data collected from SOF personnel engaged in 12 different SOF training scenarios. Energy expenditure and total body water were determined using the doubly-labeled water technique. Physical activity level was determined as daily energy expenditure divided by resting metabolic rate. Physical activity level was broken into quartiles (0 = mission prep, 1 = common warrior tasks, 2 = battle drills, 3 = specialized intense activity) to generate a physical activity factor (PAF). Regression analysis was used to construct two predictive equations (Model A; body mass and PAF, Model B; fat-free mass and PAF) estimating daily energy expenditures. Average measured energy expenditure during SOF training was 4468 (range: 3700 to 6300) Kcal·d- 1 . Regression analysis revealed that physical activity level ( r = 0.91; P < 0.05) and body mass ( r = 0.28; P < 0.05; Model A), or fat-free mass (FFM; r = 0.32; P < 0.05; Model B) were the factors that most highly predicted energy expenditures. Predictive equations coupling PAF with body mass (Model A) and FFM (Model B), were correlated ( r = 0.74 and r = 0.76, respectively) and did not differ [mean ± SEM: Model A; 4463 ± 65 Kcal·d - 1 , Model B; 4462 ± 61 Kcal·d - 1 ] from DLW measured energy expenditures. By quantifying and grouping SOF training exercises into activity factors, SOF energy requirements can be predicted with reasonable accuracy and these equations used by dietetic/logistical personnel to plan appropriate feeding regimens to meet SOF nutritional requirements across their mission profile.
Light Water Reactor Sustainability Program: Integrated Program Plan
DOE Office of Scientific and Technical Information (OSTI.GOV)
None, None
Nuclear power has safely, reliably, and economically contributed almost 20% of electrical generation in the United States over the past two decades. It remains the single largest contributor (more than 60%) of non-greenhouse-gas-emitting electric power generation in the United States. Domestic demand for electrical energy is expected to grow by about 24% from 2013 to 2040 . At the same time, most of the currently operating nuclear power plants will begin reaching the end of their initial 20-year extension to their original 40-year operating license, for a total of 60 years of operation (the oldest commercial plants in the Unitedmore » States reached their 40th anniversary in 2009). Figure E-1 shows projected nuclear energy contribution to the domestic generating capacity for 40- and 60-year license periods. If current operating nuclear power plants do not operate beyond 60 years (and new nuclear plants are not built quickly enough to replace them), the total fraction of generated electrical energy from nuclear power will rapidly decline. That decline will be accelerated if plants are shut down before 60 years of operation. Decisions on extended operation ultimately rely on economic factors; however, economics can often be improved through technical advancements. The U.S. Department of Energy Office of Nuclear Energy’s 2010 Research and Development Roadmap (2010 Nuclear Energy Roadmap) organizes its activities around four objectives that ensure nuclear energy remains a compelling and viable energy option for the United States. The four objectives are as follows: 1. Develop technologies and other solutions that can improve the reliability, sustain the safety, and extend the life of the current reactors; 2. Develop improvements in the affordability of new reactors to enable nuclear energy to help meet the Administration’s energy security and climate change goals; 3. Develop sustainable nuclear fuel cycles; and 4. Understand and minimize the risks of nuclear proliferation and terrorism. The Light Water Reactor Sustainability (LWRS) Program is the primary programmatic activity that addresses Objective 1. This document summarizes the LWRS Program’s plans. For the LWRS Program, sustainability is defined as the ability to maintain safe and economic operation of the existing fleet of nuclear power plants for a longer-than-initially-licensed lifetime. It has two facets with respect to long-term operations: (1) manage the aging of plant systems, structures, and components so that nuclear power plant lifetimes can be extended and the plants can continue to operate safely, efficiently, and economically; and (2) provide science-based solutions to the industry to implement technology to exceed the performance of the current labor-intensive business model.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Yang, Zhaoqing; Wang, Taiping
A three-dimensional coastal ocean model with a tidal turbine module was used in this paper to study the effects of tidal energy extraction on temperature and salinity stratification and density driven two-layer estuarine circulation. Numerical experiments with various turbine array configurations were carried out to investigate the changes in tidally mean temperature, salinity and velocity profiles in an idealized stratified estuary that connects to coastal water through a narrow tidal channel. The model was driven by tides, river inflow and sea surface heat flux. To represent the realistic size of commercial tidal farms, model simulations were conducted based on amore » small percentage of the total number of turbines that would generate the maximum extractable energy in the system. Model results indicated that extraction of tidal energy will increase the vertical mixing and decrease the stratification in the estuary. Extraction of tidal energy has stronger impact on the tidally-averaged salinity, temperature and velocity in the surface layer than the bottom. Energy extraction also weakens the two-layer estuarine circulation, especially during neap tides when tidal mixing the weakest and energy extraction is the smallest. Model results also show that energy generation can be much more efficient with higher hub height with relatively small changes in stratification and two-layer estuarine circulation.« less
Relationship between wave energy and free energy from pickup ions in the Comet Halley environment
NASA Technical Reports Server (NTRS)
Huddleston, D. E.; Johnstone, A. D.
1992-01-01
The free energy available from the implanted heavy ion population at Comet Halley is calculated by assuming that the initial unstable velocity space ring distribution of the ions evolves toward a bispherical shell. Ultimately this free energy adds to the turbulence in the solar wind. Upstream and downstream free energies are obtained separately for the conditions observed along the Giotto spacecraft trajectory. The results indicate that the waves are mostly upstream propagating in the solar wind frame. The total free energy density always exceeds the measured wave energy density because, as expected in the nonlinear process of ion scattering, the available energy is not all immediately released. An estimate of the amount which has been released can be obtained from the measured oxygen ion distributions and again it exceeds that observed. The theoretical analysis is extended to calculate the k spectrum of the cometary-ion-generated turbulence.
Earth's changing global atmospheric energy cycle in response to climate change
Pan, Yefeng; Li, Liming; Jiang, Xun; Li, Gan; Zhang, Wentao; Wang, Xinyue; Ingersoll, Andrew P.
2017-01-01
The Lorenz energy cycle is widely used to investigate atmospheres and climates on planets. However, the long-term temporal variations of such an energy cycle have not yet been explored. Here we use three independent meteorological data sets from the modern satellite era, to examine the temporal characteristics of the Lorenz energy cycle of Earth's global atmosphere in response to climate change. The total mechanical energy of the global atmosphere basically remains constant with time, but the global-average eddy energies show significant positive trends. The spatial investigations suggest that these positive trends are concentrated in the Southern Hemisphere. Significant positive trends are also found in the conversion, generation and dissipation rates of energies. The positive trends in the dissipation rates of kinetic energies suggest that the efficiency of the global atmosphere as a heat engine increased during the modern satellite era. PMID:28117324
DOE Office of Scientific and Technical Information (OSTI.GOV)
Steinberg, Daniel; Bielen, Dave; Eichman, Josh
Electrification of end-use services in the transportation, buildings, and industrial sectors coupled with decarbonization of electricity generation has been identified as one of the key pathways to achieving a low-carbon future in the United States. By lowering the carbon intensity of the electricity generation and substituting electricity for higher-emissions fossil fuels in end-use sectors, significant reductions in carbon dioxide emissions can be achieved. This report describes a preliminary analysis that examines the potential impacts of widespread electrification on the U.S. energy sector. We develop a set of exploratory scenarios under which electrification is aggressively pursued across all end-use sectors andmore » examine the impacts of achieving these electrification levels on electricity load patterns, total fossil energy consumption, carbon dioxide emissions, and the evolution of the U.S. power system.« less
Heestand, G M; Haynam, C A; Wegner, P J; Bowers, M W; Dixit, S N; Erbert, G V; Henesian, M A; Hermann, M R; Jancaitis, K S; Knittel, K; Kohut, T; Lindl, J D; Manes, K R; Marshall, C D; Mehta, N C; Menapace, J; Moses, E; Murray, J R; Nostrand, M C; Orth, C D; Patterson, R; Sacks, R A; Saunders, R; Shaw, M J; Spaeth, M; Sutton, S B; Williams, W H; Widmayer, C C; White, R K; Whitman, P K; Yang, S T; Van Wonterghem, B M
2008-07-01
A single beamline of the National Ignition Facility (NIF) has been operated at a wavelength of 526.5 nm (2 omega) by frequency converting the fundamental 1053 nm (1 omega) wavelength with an 18.2 mm thick type-I potassium dihydrogen phosphate (KDP) second-harmonic generator (SHG) crystal. Second-harmonic energies of up to 17.9 kJ were measured at the final optics focal plane with a conversion efficiency of 82%. For a similarly configured 192-beam NIF, this scales to a total 2 omega energy of 3.4 MJ full NIF equivalent (FNE).
Thermal Analysis of the Mound One Kilowatt Package
DOE Office of Scientific and Technical Information (OSTI.GOV)
Or, Chuen T.
The Mound One Kilowatt (1 KW) package was designed for the shipment of plutonium (Pu-238) with not more than 1 kW total heat dissipation. To comply with regulations, the Mound 1 kW package has to pass all the requirements under Normal Conditions of Transport (NCT; 38 degrees C ambient temperature) and Hypothetical Accident Conditions (HAC; package engulfed in fire for 30 minutes). Analytical and test results were presented in the Safety Analysis Report for Packaging (SARP) for the Mound 1 kW package, revision 1, April 1991. Some issues remained unresolved in that revision. In March 1992, Fairchild Space and Defensemore » Corporation was commissioned by the Department of Energy to perform the thermal analyses. 3-D thermal models were created to perform the NCT and HAC analyses. Four shipping configurations in the SARP revision 3 were analyzed. They were: (1) The GPHS graphite impact shell (GIS) in the threaded product can (1000 W total heat generation); (2) The fueled clads in the welded product can (1000 W total heat generation); (3) The General Purpose Heat Source (GPHS) module (750 W total heat generation); and (4) The Multi-Hundred Watt (MHW) spheres (810 W total heat generation). Results from the four cases show that the GIS or fuel clad in the product can is the worse case. The temperatures predicted under NCT and HAC in all four cases are within the design limits. The use of helium instead of argon as cover gas provides a bigger safety margin. There is a duplicate copy.« less
Selenide isotope generator for the Galileo mission. Reliability program plan
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
1978-10-01
The reliability program plan for the Selenide Isotope Generator (SIG) program is presented. It delineates the specific tasks that will be accomplished by Teledyne Energy Systems and its suppliers during design, development, fabrication and test of deliverable Radioisotopic Thermoelectric Generators (RTG), Electrical Heated Thermoelectric Generators (ETG) and associated Ground Support Equipment (GSE). The Plan is formulated in general accordance with procedures specified in DOE Reliability Engineering Program Requirements Publication No. SNS-2, dated June 17, 1974. The Reliability Program Plan presented herein defines the total reliability effort without further reference to Government Specifications. The reliability tasks to be accomplished are delineatedmore » herein and become the basis for contract compliance to the extent specified in the SIG contract Statement of Work.« less
Why do Electrons with "Anomalous Energies" appear in High-Pressure Gas Discharges?
NASA Astrophysics Data System (ADS)
Kozyrev, Andrey; Kozhevnikov, Vasily; Semeniuk, Natalia
2018-01-01
Experimental studies connected with runaway electron beams generation convincingly shows the existence of electrons with energies above the maximum voltage applied to the discharge gap. Such electrons are also known as electrons with "anomalous energies". We explain the presence of runaway electrons having so-called "anomalous energies" according to physical kinetics principles, namely, we describe the total ensemble of electrons with the distribution function. Its evolution obeys Boltzmann kinetic equation. The dynamics of self-consistent electromagnetic field is taken into the account by adding complete Maxwell's equation set to the resulting system of equations. The electrodynamic mechanism of the interaction of electrons with a travelling-wave electric field is analyzed in details. It is responsible for the appearance of electrons with high energies in real discharges.
DOD fuel cell demonstration program
DOE Office of Scientific and Technical Information (OSTI.GOV)
Holcomb, F.H.; Binder, M.J.; Taylor, W.R.
The supply of reliable, cost-effective electric power with minimal environmental impact is a constant concern of Department of Defense (DOD) installation energy personnel. Electricity purchased from the local utility is expensive and represents only about 30% of the original energy input at the generating station due to generation and distribution inefficiencies. Because of master metering and large air conditioning loads, the demand portion of the installation`s electric bill can be in excess of 50% of the total bill. While the electric utilities in the United States have a very good record of reliability, there is significant potential for improving themore » security of electrical power supplied by using on-site power generation. On-site, dispersed power generation can reduce power outages due to weather, terrorist activities, or lack of utility generating capacity. In addition, as increased emphasis is placed on global warming, acid rain, and air pollution in general, the development of clean, highly efficient power producing technologies is not only desirable, but mandatory. Since the majority of central heat plants on U.S. military installations are nearing the end of their useful life, there is an opportunity to replace outdated existing equipment with modem technologies.« less
Federal Register 2010, 2011, 2012, 2013, 2014
2010-08-30
... and Fairmont) and two existing, 36- and 54- inch diameter steel pipelines; (2) three proposed powerhouses, each to contain a 0.37-megawatt-(MW) turbine-generating unit, with a total capacity of 1.11 MW...-in point of a local power company grid system. The project would produce an estimated average annual...
Energy and operation management of a microgrid using particle swarm optimization
NASA Astrophysics Data System (ADS)
Radosavljević, Jordan; Jevtić, Miroljub; Klimenta, Dardan
2016-05-01
This article presents an efficient algorithm based on particle swarm optimization (PSO) for energy and operation management (EOM) of a microgrid including different distributed generation units and energy storage devices. The proposed approach employs PSO to minimize the total energy and operating cost of the microgrid via optimal adjustment of the control variables of the EOM, while satisfying various operating constraints. Owing to the stochastic nature of energy produced from renewable sources, i.e. wind turbines and photovoltaic systems, as well as load uncertainties and market prices, a probabilistic approach in the EOM is introduced. The proposed method is examined and tested on a typical grid-connected microgrid including fuel cell, gas-fired microturbine, wind turbine, photovoltaic and energy storage devices. The obtained results prove the efficiency of the proposed approach to solve the EOM of the microgrids.
Electric Power Quarterly, July-September 1984
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
1985-01-01
The Electric Power Quarterly (EPQ) provides electric utilities' plant-level information about the cost, quantity, and quality of fossil fuel receipts, net generation, fuel consumption, and fuel stocks. The EPQ contains monthly data and quarterly totals for the reporting quarter. In this report, data collected on Form EIA-759 regarding electric utilities' net generation, fuel consumption, and fuel stocks are presented on a plant-by-plant basis. In addition, quantity, cost, and quality of fossil fuel receipts collected on the Federal Energy Regulatory Commission (FERC) Form 423 are presented on a plant-by-plant basis.
Electric Power Quarterly, October-December 1984
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
1985-04-01
The Electric Power Quarterly (EPQ) provides electric utilities' plant-level information about the cost, quantity, and quality of fossil fuel receipts, net generation, fuel consumption, and fuel stocks. The EPQ contains monthly data and quarterly totals for the reporting quarter. In this report, data collected on Form EIA-759 regarding electric utilities' net generation, fuel consumption, and fuel stocks are presented on a plant-by-plant basis. In addition, quantity, cost, and quality of fossil fuel receipts collected on the Federal Energy Regulatory Commission (FERC) Form 423 are presented on a plant-by-plant basis.
Dynamic management of integrated residential energy systems
NASA Astrophysics Data System (ADS)
Muratori, Matteo
This study combines principles of energy systems engineering and statistics to develop integrated models of residential energy use in the United States, to include residential recharging of electric vehicles. These models can be used by government, policymakers, and the utility industry to provide answers and guidance regarding the future of the U.S. energy system. Currently, electric power generation must match the total demand at each instant, following seasonal patterns and instantaneous fluctuations. Thus, one of the biggest drivers of costs and capacity requirement is the electricity demand that occurs during peak periods. These peak periods require utility companies to maintain operational capacity that often is underutilized, outdated, expensive, and inefficient. In light of this, flattening the demand curve has long been recognized as an effective way of cutting the cost of producing electricity and increasing overall efficiency. The problem is exacerbated by expected widespread adoption of non-dispatchable renewable power generation. The intermittent nature of renewable resources and their non-dispatchability substantially limit the ability of electric power generation of adapting to the fluctuating demand. Smart grid technologies and demand response programs are proposed as a technical solution to make the electric power demand more flexible and able to adapt to power generation. Residential demand response programs offer different incentives and benefits to consumers in response to their flexibility in the timing of their electricity consumption. Understanding interactions between new and existing energy technologies, and policy impacts therein, is key to driving sustainable energy use and economic growth. Comprehensive and accurate models of the next-generation power system allow for understanding the effects of new energy technologies on the power system infrastructure, and can be used to guide policy, technology, and economic decisions. This dissertation presents a bottom-up highly resolved model of a generic residential energy eco-system in the United States. The model is able to capture the entire energy footprint of an individual household, to include all appliances, space conditioning systems, in-home charging of plug-in electric vehicles, and any other energy needs, viewing residential and transportation energy needs as an integrated continuum. The residential energy eco-system model is based on a novel bottom-up approach that quantifies consumer energy use behavior. The incorporation of stochastic consumer behaviors allows capturing the electricity consumption of each residential specific end-use, providing an accurate estimation of the actual amount of available controllable resources, and for a better understanding of the potential of residential demand response programs. A dynamic energy management framework is then proposed to manage electricity consumption inside each residential energy eco-system. Objective of the dynamic energy management framework is to optimize the scheduling of all the controllable appliances and in-home charging of plug-in electric vehicles to minimize cost. Such an automated energy management framework is used to simulate residential demand response programs, and evaluate their impact on the electric power infrastructure. For instance, time-varying electricity pricing might lead to synchronization of the individual residential demands, creating pronounced rebound peaks in the aggregate demand that are higher and steeper than the original demand peaks that the time-varying electricity pricing structure intended to eliminate. The modeling tools developed in this study can serve as a virtual laboratory for investigating fundamental economic and policy-related questions regarding the interplay of individual consumers with energy use. The models developed allow for evaluating the impact of different energy policies, technology adoption, and electricity price structures on the total residential electricity demand. In particular, two case studies are reported in this dissertation to illustrate application of the tools developed. The first considers the impact of market penetration of plug-in electric vehicles on the electric power infrastructure. The second provides a quantitative comparison of the impact of different electricity price structures on residential demand response. Simulation results and an electricity price structure, called Multi-TOU, aimed at solving the rebound peak issue, are presented.
A new approach to wind energy: Opportunities and challenges
NASA Astrophysics Data System (ADS)
Dabiri, John O.; Greer, Julia R.; Koseff, Jeffrey R.; Moin, Parviz; Peng, Jifeng
2015-03-01
Despite common characterizations of modern wind energy technology as mature, there remains a persistent disconnect between the vast global wind energy resource—which is 20 times greater than total global power consumption—and the limited penetration of existing wind energy technologies as a means for electricity generation worldwide. We describe an approach to wind energy harvesting that has the potential to resolve this disconnect by geographically distributing wind power generators in a manner that more closely mirrors the physical resource itself. To this end, technology development is focused on large arrays of small wind turbines that can harvest wind energy at low altitudes by using new concepts of biology-inspired engineering. This approach dramatically extends the reach of wind energy, as smaller wind turbines can be installed in many places that larger systems cannot, especially in built environments. Moreover, they have lower visual, acoustic, and radar signatures, and they may pose significantly less risk to birds and bats. These features can be leveraged to attain cultural acceptance and rapid adoption of this new technology, thereby enabling significantly faster achievement of state and national renewable energy targets than with existing technology alone. Favorable economics stem from an orders-of-magnitude reduction in the number of components in a new generation of simple, mass-manufacturable (even 3D-printable), vertical-axis wind turbines. However, this vision can only be achieved by overcoming significant scientific challenges that have limited progress over the past three decades. The following essay summarizes our approach as well as the opportunities and challenges associated with it, with the aim of motivating a concerted effort in basic and applied research in this area.
NASA Astrophysics Data System (ADS)
Stoffel, Thomas L.; Myers, Daryl R.
2010-08-01
Measurement stations for solar radiation resource assessment data are expensive and labor intensive. For this reason, long-term solar radiation measurements are not widely available. Growing interest in solar renewable energy systems has generated a great number of questions about the quality of data obtained from inexpensive silicon photodiode radiometers versus costly thermopile radiometers. We analyze a year of daily total and monthly mean global horizontal irradiance measurements derived from 1-minute averages of 3-second samples of pyranometer signals. The data were collected simultaneously from both types of radiometers at the Solar Radiation Research Laboratory (SRRL) operated by the National Renewable Energy Laboratory in Golden, Colorado. All broadband radiometers in service at SRRL are calibrated annually using an outdoor method with reference radiometers traceable to the World Radiometric Reference. We summarized the data by daily total and monthly mean daily total amounts of solar radiation. Our results show that systematic and random errors (identified in our outdoor calibration process) in each type of radiometer cancel out over periods of one day or more. Daily total and mean monthly daily total solar energy measured by the two pyranometer types compare within 1% to 2%. The individual daily variations among different models of thermopile radiometers may be up to twice as large, up to +/-5%, being highest in the winter (higher average solar zenith angle conditions) and lowest in summer, consistent with the lower solar zenith angle conditions.
Riva, C; Schievano, A; D'Imporzano, G; Adani, F
2014-08-01
The purpose of this study was to observe the economic sustainability of three different biogas full scale plants, fed with different organic matrices: energy crops (EC), manure, agro-industrial (Plants B and C) and organic fraction of municipal solid waste (OFMSW) (Plant A). The plants were observed for one year and total annual biomass feeding, biomass composition and biomass cost (€ Mg(-1)), initial investment cost and plant electric power production were registered. The unit costs of biogas and electric energy (€ Sm(-3)biogas, € kWh(-1)EE) were differently distributed, depending on the type of feed and plant. Plant A showed high management/maintenance cost for OFMSW treatment (0.155 € Sm(-3)biogas, 45% of total cost), Plant B suffered high cost for EC supply (0.130 € Sm(-3)biogas, 49% of total cost) and Plant C showed higher impact on the total costs because of the depreciation charge (0.146 € Sm(-3)biogas, 41% of total costs). The breakeven point for the tariff of electric energy, calculated for the different cases, resulted in the range 120-170 € MWh(-1)EE, depending on fed materials and plant scale. EC had great impact on biomass supply costs and should be reduced, in favor of organic waste and residues; plant scale still heavily influences the production costs. The EU States should drive incentives in dependence of these factors, to further develop this still promising sector. Copyright © 2014 Elsevier Ltd. All rights reserved.
Energy deposition calculated by PHITS code in Pb spallation target
NASA Astrophysics Data System (ADS)
Yu, Quanzhi
2016-01-01
Energy deposition in a Pb spallation target irradiated by high energetic protons was calculated by PHITS2.52 code. The validation of the energy deposition and neutron production calculated by PHITS code was performed. Results show good agreements between the simulation results and the experimental data. Detailed comparison shows that for the total energy deposition, PHITS simulation result was about 15% overestimation than that of the experimental data. For the energy deposition along the length of the Pb target, the discrepancy mainly presented at the front part of the Pb target. Calculation indicates that most of the energy deposition comes from the ionizations of the primary protons and the produced secondary particles. With the event generator mode of PHITS, the deposit energy distribution for the particles and the light nulclei is presented for the first time. It indicates that the primary protons with energy more than 100 MeV are the most contributors to the total energy deposition. The energy depositions peaking at 10 MeV and 0.1 MeV, are mainly caused by the electrons, pions, d, t, 3He and also α particles during the cascade process and the evaporation process, respectively. The energy deposition density caused by different proton beam profiles are also calculated and compared. Such calculation and analyses are much helpful for better understanding the physical mechanism of energy deposition in the spallation target, and greatly useful for the thermal hydraulic design of the spallation target.
NASA Astrophysics Data System (ADS)
Devita, W. H.; Fauzi, A. M.; Purwanto, Y. A.
2018-05-01
Indonesia has the big potency of biomass. The source of biomass energy is scattered all over the country. The big potential in concentrated scale is on the island of Sumatera. Jambi province which is located in Sumatra Island has the potency of biomass energy due to a huge area for estate crop and agriculture. The Indonesian government had issued several policies which put a higher priority on the utilization of renewable energy. This study aimed to identify the conditions and distribution of biomass waste potential in Jambi province. The potential biomass waste in Jambi province was 27,407,183 tons per year which dominated of oil palm residue (46.16%), rice husk and straw (3.52%), replanting rubberwood (50.32%). The total power generated from biomass waste was 129 GWhth per year which is consisted of palm oil residue (56 GWhth per year), rice husk and straw (3.22 GWhth per year), rubberwood (70.56 GWhth per year). Based on the potential of biomass waste, then the province of Jambi could obtain supplies of renewable energy from waste biomass with electricity generated amount to 32.34 GWhe per year.
Quantitative Imaging of Energy Expenditure in Human Brain
Zhu, Xiao-Hong; Qiao, Hongyan; Du, Fei; Xiong, Qiang; Liu, Xiao; Zhang, Xiaoliang; Ugurbil, Kamil; Chen, Wei
2012-01-01
Despite the essential role of the brain energy generated from ATP hydrolysis in supporting cortical neuronal activity and brain function, it is challenging to noninvasively image and directly quantify the energy expenditure in the human brain. In this study, we applied an advanced in vivo 31P MRS imaging approach to obtain regional cerebral metabolic rates of high-energy phosphate reactions catalyzed by ATPase (CMRATPase) and creatine kinase (CMRCK), and to determine CMRATPase and CMRCK in pure grey mater (GM) and white mater (WM), respectively. It was found that both ATPase and CK rates are three times higher in GM than WM; and CMRCK is seven times higher than CMRATPase in GM and WM. Among the total brain ATP consumption in the human cortical GM and WM, 77% of them are used by GM in which approximately 96% is by neurons. A single cortical neuron utilizes approximately 4.7 billion ATPs per second in a resting human brain. This study demonstrates the unique utility of in vivo 31P MRS imaging modality for direct imaging of brain energy generated from ATP hydrolysis, and provides new insights into the human brain energetics and its role in supporting neuronal activity and brain function. PMID:22487547
Electric urban delivery trucks: energy use, greenhouse gas emissions, and cost-effectiveness.
Lee, Dong-Yeon; Thomas, Valerie M; Brown, Marilyn A
2013-07-16
We compare electric and diesel urban delivery trucks in terms of life-cycle energy consumption, greenhouse gas (GHG) emissions, and total cost of ownership (TCO). The relative benefits of electric trucks depend heavily on vehicle efficiency associated with drive cycle, diesel fuel price, travel demand, electric drive battery replacement and price, electricity generation and transmission efficiency, electric truck recharging infrastructure, and purchase price. For a drive cycle with frequent stops and low average speed such as the New York City Cycle (NYCC), electric trucks emit 42-61% less GHGs and consume 32-54% less energy than diesel trucks, depending upon vehicle efficiency cases. Over an array of possible conditions, the median TCO of electric trucks is 22% less than that of diesel trucks on the NYCC. For a drive cycle with less frequent stops and high average speed such as the City-Suburban Heavy Vehicle Cycle (CSHVC), electric trucks emit 19-43% less GHGs and consume 5-34% less energy, but cost 1% more than diesel counterparts. Considering current and projected U.S. regional electricity generation mixes, for the baseline case, the energy use and GHG emissions ratios of electric to diesel trucks range from 48 to 82% and 25 to 89%, respectively.
NASA Astrophysics Data System (ADS)
Solodov, A. A.; Rosenberg, M. J.; Myatt, J. F.; Epstein, R.; Seka, W.; Hohenberger, M.; Short, R. W.; Shaw, J. G.; Regan, S. P.; Froula, D. H.; Radha, P. B.; Bates, J. W.; Schmitt, A. J.; Michel, P.; Moody, J. D.; Ralph, J. E.; Turnbull, D. P.; Barrios, M. A.
2016-10-01
Laser-plasma interaction instabilities, such as two-plasmon decay (TPD) and stimulated Raman scattering (SRS), can be detrimental for direct-drive inertial confinement fusion because of target preheat by generated high-energy electrons. The radiation-hydrodynamics code DRACO has been used to design planar-target experiments that generate plasma and interaction conditions relevant to direct-drive-ignition designs (IL 1015 W / cm 2 , Te > 3 KeV density gradient scale lengths of Ln 600 μm) . The hot-electron temperature of 40to50keV and the fraction of laser energy converted to hot electrons of 0.5to were inferred based on comparing the simulated and experimentally observed x-ray emission when the laser intensity at the quarter-critical surface increased from 6 to 15 ×1014 W / cm 2 . The measured SRS energy was sufficient to explain the observed total energy in hot electrons. Implications for ignition-scale direct-drive experiments and hot-electron preheat mitigation using mid- Z ablators will be discussed. This material is based upon work supported by the Department of Energy National Nuclear Security Administration under Award Number DE-NA0001944.
Electric Power Quarterly, July-September 1985
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
1986-01-29
The Electric Power Quarterly (EPQ) provides electric utilities' plant-level information about the cost, quantity, and quality of fossil fuel receipts, net generation, fuel consumption, and fuel stocks. The EPQ contains monthly data and quarterly totals for the reporting quarter. The data presented in this report were collected and published by the Energy Information Administration (EIA), to fulfill its responsibilities as specified in the Federal Energy Administration Act of 1974 (P.L. 93-275) as amended. This edition of the EPQ contains monthly data for the third quarter of 1985.
NASA Astrophysics Data System (ADS)
Iwayama, H.; Sugishima, A.; Nagaya, K.; Yao, M.; Fukuzawa, H.; Motomura, K.; Liu, X.-J.; Yamada, A.; Wang, C.; Ueda, K.; Saito, N.; Nagasono, M.; Tono, K.; Yabashi, M.; Ishikawa, T.; Ohashi, H.; Kimura, H.; Togashi, T.
2010-08-01
The emission of highly charged ions from Xe clusters exposed to intense extreme ultraviolet laser pulses (λ ~ 52 nm) from the free electron laser in Japan was investigated using ion momentum spectroscopy. With increasing average cluster size, we observed multiply charged ions Xez + up to z = 3. From kinetic energy distributions, we found that multiply charged ions were generated near the cluster surface. Our results suggest that charges are inhomogeneously redistributed in the cluster to lower the total energy stored in the clusters.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Cochran, Jaquelin; Palchak, David
The Greening the Grid: Pathways to Integrate 175 Gigawatts of Renewable Energy into India's Electric Grid study uses advanced weather and power system modeling to explore the operational impacts of meeting India's 2022 renewable energy targets and identify actions that may be favorable for integrating high levels of renewable energy into the Indian grid. The study relies primarily on a production cost model that simulates optimal scheduling and dispatch of available generation in a future year (2022) by minimizing total production costs subject to physical, operational, and market constraints. This fact sheet provides a detailed look at each of thesemore » models, including their common assumptions and the insights provided by each.« less
Renewable Energy Power Generation Estimation Using Consensus Algorithm
NASA Astrophysics Data System (ADS)
Ahmad, Jehanzeb; Najm-ul-Islam, M.; Ahmed, Salman
2017-08-01
At the small consumer level, Photo Voltaic (PV) panel based grid tied systems are the most common form of Distributed Energy Resources (DER). Unlike wind which is suitable for only selected locations, PV panels can generate electricity almost anywhere. Pakistan is currently one of the most energy deficient countries in the world. In order to mitigate this shortage the Government has recently announced a policy of net-metering for residential consumers. After wide spread adoption of DERs, one of the issues that will be faced by load management centers would be accurate estimate of the amount of electricity being injected in the grid at any given time through these DERs. This becomes a critical issue once the penetration of DER increases beyond a certain limit. Grid stability and management of harmonics becomes an important consideration where electricity is being injected at the distribution level and through solid state controllers instead of rotating machinery. This paper presents a solution using graph theoretic methods for the estimation of total electricity being injected in the grid in a wide spread geographical area. An agent based consensus approach for distributed computation is being used to provide an estimate under varying generation conditions.
NASA Astrophysics Data System (ADS)
Zhang, Xinhua; Zhou, Zhongkang; Chen, Xiaochun; Song, Jishuang; Shi, Maolin
2017-05-01
system is proposed based on NaS battery and lithium ion battery, that the former is the main large scale energy storage technology world-widely used and developed and the latter is a flexible way to have both power and energy capacities. The hybrid energy storage system, which takes advantage of the two complementary technologies to provide large power and energy capacities, is chosen to do an evaluation of econom ical-environmental based on critical excess electricity production (CEEP), CO2 emission, annual total costs calculated on the specific given condition using Energy PLAN software. The result shows that hybrid storage system has strengths in environmental benefits and also can absorb more discarded wind power than single storage system and is a potential way to push forward the application of wind power and even other types of renewable energy resources.
Regimes of enhanced electromagnetic emission in beam-plasma interactions
DOE Office of Scientific and Technical Information (OSTI.GOV)
Timofeev, I. V.; Annenkov, V. V.; Arzhannikov, A. V.
2015-11-15
The ways to improve the efficiency of electromagnetic waves generation in laboratory experiments with high-current relativistic electron beams injected into a magnetized plasma are discussed. It is known that such a beam can lose, in a plasma, a significant part of its energy by exciting a high level of turbulence and heating plasma electrons. Beam-excited plasma oscillations may simultaneously participate in nonlinear processes resulting in a fundamental and second harmonic emissions. It is obvious, however, that in the developed plasma turbulence the role of these emissions in the total energy balance is always negligible. In this paper, we investigate whethermore » electromagnetic radiation generated in the beam-plasma system can be sufficiently enhanced by the direct linear conversion of resonant beam-driven modes into electromagnetic ones on preformed regular inhomogeneities of plasma density. Due to the high power of relativistic electron beams, the mechanism discussed may become the basis for the generator of powerful sub-terahertz radiation.« less
Electrolytic treatment of Standard Malaysian Rubber process wastewater.
Vijayaraghavan, Krishnan; Ahmad, Desa; Yazid, Ahmad Yuzri Ahmad
2008-01-31
A new method of Standard Malaysian Rubber (SMR) process wastewater treatment was developed based on in situ hypochlorous acid generation. The hypochlorous acid was generated in an undivided electrolytic cell consisting of two sets of graphite as anode and stainless sheets as cathode. The generated hypochlorous acid served as an oxidizing agent to destroy the organic matter present in the SMR wastewater. For an influent COD concentration of 2960 mg/L at an initial pH 4.5+/-0.1, current density 74.5 mA/cm(2), sodium chloride content 3% and electrolysis period of 75 min, resulted in the following residual values pH 7.5, COD 87 mg/L, BOD(5) 60 mg/L, TOC 65 mg/L, total chlorine 146 mg/L, turbidity 7 NTU and temperature 48 degrees C, respectively. In the case of 2% sodium chloride as an electrolyte for the above said operating condition resulted in the following values namely: pH 7.2, COD 165 mg/L, BOD(5) 105 mg/L, TOC 120 mg/L, total chlorine 120 mg/L, turbidity 27 NTU and temperature 53 degrees C, respectively. The energy requirement were found to be 30 and 46 Wh/L, while treating 24 L of SMR wastewater at 2 and 3% sodium chloride concentration at a current density 74.5 mA/cm(2). The observed energy difference was due to the improved conductivity at high sodium chloride content.
Magnetic Field Generation, Particle Energization and Radiation at Relativistic Shear Boundary Layers
NASA Astrophysics Data System (ADS)
Liang, Edison; Fu, Wen; Spisak, Jake; Boettcher, Markus
2015-11-01
Recent large scale Particle-in-Cell (PIC) simulations have demonstrated that in unmagnetized relativistic shear flows, strong transverse d.c. magnetic fields are generated and sustained by ion-dominated currents on the opposite sides of the shear interface. Instead of dissipating the shear flow free energy via turbulence formation and mixing as it is usually found in MHD simulations, the kinetic results show that the relativistic boundary layer stabilizes itself via the formation of a robust vacuum gap supported by a strong magnetic field, which effectively separates the opposing shear flows, as in a maglev train. Our new PIC simulations have extended the runs to many tens of light crossing times of the simulation box. Both the vacuum gap and supporting magnetic field remain intact. The electrons are energized to reach energy equipartition with the ions, with 10% of the total energy in electromagnetic fields. The dominant radiation mechanism is similar to that of a wiggler, due to oscillating electron orbits around the boundary layer.
Strong electromagnetic pulses generated in high-intensity laser-matter interactions
NASA Astrophysics Data System (ADS)
Rączka, P.; Dubois, J.-L.; Hulin, S.; Rosiński, M.; Zaraś-Szydłowska, A.; Badziak, J.
2018-01-01
Results are reported of an experiment performed at the Eclipse laser facility in CELIA, Bordeaux, on the generation of strong electromagnetic pulses. Measurements were performed of the target neutralization current, the total target charge and the tangential component of the magnetic field for the laser energies ranging from 45 mJ to 92 mJ with the pulse duration approximately 40 fs, and for the pulse durations ranging from 39 fs to 1000 fs, with the laser energy approximately 90 mJ. It was found that the values obtained for thick (mm scale) Cu targets are visibly higher than values reported in previous experiments, which is argued to be a manifestation of a strong dependence of the target electric polarization process on the laser contrast and hence on the amount of preplasma. It was also found that values obtained for thin (μm scale) Al foils were visibly higher than values for thick Cu targets, especially for pulse durations longer than 100 fs. The correlations between the total target charge versus the maximum value of the target neutralization current, and the maximum value of the tangential component of the magnetic field versus the total target charge were analysed. They were found to be in very good agreement with correlations seen in data from previous experiments, which provides a good consistency check on our experimental procedures.
Decomposition analysis of the waste generation and management in 30 European countries.
Korica, Predrag; Cirman, Andreja; Žgajnar Gotvajn, Andreja
2016-11-01
An often suggested method for waste prevention is substitution of currently-used materials with materials which are less bulky, contain less hazardous components or are easier to recycle. For policy makers it is important to have tools available that provide information on the impact of this substitution on the changes in total amounts of waste generated and managed. The purpose of this paper is to see how much changes in the mix of 15 waste streams generated in eight economic sectors from 30 European countries have influenced the amounts of waste generated and managed in the period 2004-2012. In order to determine these impacts, two variations of the logarithmic mean Divisia index (LMDI) analysis model were developed and applied. The results show that the changes in the mix of waste streams in most cases did not have a considerable influence on the changes in the amounts of generated waste. In the analyses of waste sent for landfill, incineration without energy recovery, incineration with energy recovery and recovery other than energy recovery, the results also show that the changes in the mix of waste streams in most cases did not have the expected/desired influence on the changes in the amounts of managed waste. This paper provides an example on the possibilities of applying the LMDI analysis as a tool for quantifying the potential of effects which implemented or planned measures could have on the changes in waste management systems. © The Author(s) 2016.
Quantifying Co-benefits of Renewable Energy through Integrated Electricity and Air Quality Modeling
NASA Astrophysics Data System (ADS)
Abel, D.
2016-12-01
This work focuses on the coordination of electricity sector changes with air quality and health improvement strategies through the integration of electricity and air quality models. Two energy models are used to calculate emission perturbations associated with changes in generation technology (20% generation from solar photovoltaics) and demand (future electricity use under a warmer climate). Impacts from increased solar PV penetration are simulated with the electricity model GridView, in collaboration with the National Renewable Energy Laboratory (NREL). Generation results are used to scale power plant emissions from an inventory developed by the Lake Michigan Air Directors Consortium (LADCO). Perturbed emissions and are used to calculate secondary particulate matter with the Community Multiscale Air Quality (CMAQ) model. We find that electricity NOx and SO2 emissions decrease at a rate similar to the total fraction of electricity supplied by solar. Across the Eastern U.S. region, average PM2.5 is reduced 5% over the summer, with highest reduction in regions and on days of greater PM2.5. A similar approach evaluates the air quality impacts of elevated electricity demand under a warmer climate. Meteorology is selected from the North American Regional Climate Change Assessment Program (NARCCAP) and input to a building energy model, eQUEST, to assess electricity demand as a function of ambient temperature. The associated generation and emissions are calculated on a plant-by-plant basis by the MyPower power sector model. These emissions are referenced to the 2011 National Emissions Inventory to be modeled in CMAQ for the Eastern U.S. and extended to health impact evaluation with the Environmental Benefits Mapping and Analysis Program (BenMAP). All results focus on the air quality and health consequences of energy system changes, considering grid-level changes to meet climate and air quality goals.
Track structure in radiation biology: theory and applications.
Nikjoo, H; Uehara, S; Wilson, W E; Hoshi, M; Goodhead, D T
1998-04-01
A brief review is presented of the basic concepts in track structure and the relative merit of various theoretical approaches adopted in Monte-Carlo track-structure codes are examined. In the second part of the paper, a formal cluster analysis is introduced to calculate cluster-distance distributions. Total experimental ionization cross-sections were least-square fitted and compared with the calculation by various theoretical methods. Monte-Carlo track-structure code Kurbuc was used to examine and compare the spectrum of the secondary electrons generated by using functions given by Born-Bethe, Jain-Khare, Gryzinsky, Kim-Rudd, Mott and Vriens' theories. The cluster analysis in track structure was carried out using the k-means method and Hartigan algorithm. Data are presented on experimental and calculated total ionization cross-sections: inverse mean free path (IMFP) as a function of electron energy used in Monte-Carlo track-structure codes; the spectrum of secondary electrons generated by different functions for 500 eV primary electrons; cluster analysis for 4 MeV and 20 MeV alpha-particles in terms of the frequency of total cluster energy to the root-mean-square (rms) radius of the cluster and differential distance distributions for a pair of clusters; and finally relative frequency distribution for energy deposited in DNA, single-strand break and double-strand breaks for 10MeV/u protons, alpha-particles and carbon ions. There are a number of Monte-Carlo track-structure codes that have been developed independently and the bench-marking presented in this paper allows a better choice of the theoretical method adopted in a track-structure code to be made. A systematic bench-marking of cross-sections and spectra of the secondary electrons shows differences between the codes at atomic level, but such differences are not significant in biophysical modelling at the macromolecular level. Clustered-damage evaluation shows: that a substantial proportion of dose ( 30%) is deposited by low-energy electrons; the majority of DNA damage lesions are of simple type; the complexity of damage increases with increased LET, while the total yield of strand breaks remains constant; and at high LET values nearly 70% of all double-strand breaks are of complex type.
Maximally reliable Markov chains under energy constraints.
Escola, Sean; Eisele, Michael; Miller, Kenneth; Paninski, Liam
2009-07-01
Signal-to-noise ratios in physical systems can be significantly degraded if the outputs of the systems are highly variable. Biological processes for which highly stereotyped signal generations are necessary features appear to have reduced their signal variabilities by employing multiple processing steps. To better understand why this multistep cascade structure might be desirable, we prove that the reliability of a signal generated by a multistate system with no memory (i.e., a Markov chain) is maximal if and only if the system topology is such that the process steps irreversibly through each state, with transition rates chosen such that an equal fraction of the total signal is generated in each state. Furthermore, our result indicates that by increasing the number of states, it is possible to arbitrarily increase the reliability of the system. In a physical system, however, an energy cost is associated with maintaining irreversible transitions, and this cost increases with the number of such transitions (i.e., the number of states). Thus, an infinite-length chain, which would be perfectly reliable, is infeasible. To model the effects of energy demands on the maximally reliable solution, we numerically optimize the topology under two distinct energy functions that penalize either irreversible transitions or incommunicability between states, respectively. In both cases, the solutions are essentially irreversible linear chains, but with upper bounds on the number of states set by the amount of available energy. We therefore conclude that a physical system for which signal reliability is important should employ a linear architecture, with the number of states (and thus the reliability) determined by the intrinsic energy constraints of the system.
Lin, Hongjian; Wu, Xiao; Nelson, Chad; Miller, Curtis; Zhu, Jun
2016-01-01
Air-cathode microbial fuel cells (MFCs) are widely tested to recover electrical energy from waste streams containing organic matter. When high-strength wastewater, such as liquid animal manure, is used as a medium, inhibition on anode and cathode catalysts potentially impairs the effectiveness of MFC performance in power generation and pollutant removal. This study evaluated possible inhibitive effects of liquid swine manure components on MFC power generation, improved liquid manure-fed MFCs performance by pretreatment (dilution and selective adsorption), and modeled the kinetics of organic matter and nutrients removal kinetics. Parameters monitored included pH, conductivity, chemical oxygen demand (COD), volatile fatty acids (VFAs), total ammoniacal nitrogen (TAN), nitrite, nitrate, and phosphate concentrations. The removals of VFA and TAN were efficient, indicated by the short half-life times of 4.99 and 7.84 d, respectively. The mechanism for phosphate decrease was principally the salt precipitation on cathode, but the removal was incomplete after 42-d operation. MFC with an external resistor of 2.2 kΩ and fed with swine wastewater generated relatively small power (28.2 μW), energy efficiency (0.37%) and Coulombic efficiency (1.5%). Dilution of swine wastewater dramatically improved the power generation as the inhibitory effect was decreased. Zeolite and granular activated carbon were effective in the selective adsorption of ammonia or organic matter in swine wastewater, and so substantially improved the power generation, energy efficiency, and Coulombic efficiency. A smaller external resistor in the circuit was also observed to promote the organic matter degradation and thus to shorten the treatment time. Overall, air-cathode MFCs are promising for generating electrical power from livestock wastewater and meanwhile reducing the level of organic matter and nutrients.
Cosmic archaeology with gravitational waves from cosmic strings
NASA Astrophysics Data System (ADS)
Cui, Yanou; Lewicki, Marek; Morrissey, David E.; Wells, James D.
2018-06-01
Cosmic strings are generic cosmological predictions of many extensions of the standard model of particle physics, such as a U (1 )' symmetry-breaking phase transition in the early Universe or remnants of superstring theory. Unlike other topological defects, cosmic strings can reach a scaling regime that maintains a small fixed fraction of the total energy density of the Universe from a very early epoch until today. If present, they will oscillate and generate gravitational waves with a frequency spectrum that imprints the dominant sources of total cosmic energy density throughout the history of the Universe. We demonstrate that current and future gravitational wave detectors, such as LIGO and LISA, could be capable of measuring the frequency spectrum of gravitational waves from cosmic strings and discerning the energy composition of the Universe at times well before primordial nucleosynthesis and the cosmic microwave background where standard cosmology has yet to be tested. This work establishes a benchmark case that gravitational waves may provide an unprecedented, powerful tool for probing the evolutionary history of the very early Universe.
A tale of two timescales: Mixing, mass generation, and phase transitions in the early universe
NASA Astrophysics Data System (ADS)
Dienes, Keith R.; Kost, Jeff; Thomas, Brooks
2016-02-01
Light scalar fields such as axions and string moduli can play an important role in early-universe cosmology. However, many factors can significantly impact their late-time cosmological abundances. For example, in cases where the potentials for these fields are generated dynamically—such as during cosmological mass-generating phase transitions—the duration of the time interval required for these potentials to fully develop can have significant repercussions. Likewise, in scenarios with multiple scalars, mixing amongst the fields can also give rise to an effective timescale that modifies the resulting late-time abundances. Previous studies have focused on the effects of either the first or the second timescale in isolation. In this paper, by contrast, we examine the new features that arise from the interplay between these two timescales when both mixing and time-dependent phase transitions are introduced together. First, we find that the effects of these timescales can conspire to alter not only the total late-time abundance of the system—often by many orders of magnitude—but also its distribution across the different fields. Second, we find that these effects can produce large parametric resonances which render the energy densities of the fields highly sensitive to the degree of mixing as well as the duration of the time interval over which the phase transition unfolds. Finally, we find that these effects can even give rise to a "reoverdamping" phenomenon which causes the total energy density of the system to behave in novel ways that differ from those exhibited by pure dark matter or vacuum energy. All of these features therefore give rise to new possibilities for early-universe phenomenology and cosmological evolution. They also highlight the importance of taking into account the time dependence associated with phase transitions in cosmological settings.
NASA Astrophysics Data System (ADS)
Medvedeva, E. A.; Zhenikhov, Yu. N.; Urvantsev, I. V.; Tsyba, V. E.
2017-06-01
This article presents a detailed analysis of the economic efficiency of peat utilization for generating electricity and heat in Russian rural areas and decentralized power consumption areas on the basis of the comparison of power tariffs (prices) and full costs of peat-based electricity and heat production. The research was performed using the model-information complex detailed with respect to municipal areas and major peat deposits that was developed at the Energy Institute, National Research University Higher School of Economics. It is shown that the firing of lignin helium fuel (LHF) granules that are made from peat extracted by the excavating method according to the new, patented technology is considered most efficient. In nongasified areas, the total cost of heat power that is generated in new boiler houses on the basis of LHF granules is often lower than the total heat cost for the gasification of the area and construction of gas boiler houses. In some cases, the heat cost in gasified areas is lower when using a boiler house based on LHF granules than that provided by the conversion of a boiler house to gas fuel. It is also shown that the construction of peat-based heat sources with the overall power of up to 27600 GJ/h that generate a heat power of up to 167.5 million GJ/year will be economically efficient in the coming years, provided that the tariffs for energy sources remain the same. Taking into account the supportive measures that were accepted on a legislative basis in July 2016, sources with the total power of up to 70 GW may be effective for peat-based plants with combined heat-andpower generation. To stimulate the utilization of peat in decentralized power consumption areas and rural areas located in the vicinity of deposits of this fuel type, it is also suggested to make amendments in the normative legal base.
Biodiesel production potential from fat fraction of municipal waste in Makkah
2017-01-01
In the Kingdom of Saudi Arabia (KSA), millions of Muslims come to perform Pilgrimage every year. Around one million ton of municipal solid waste (MSW) is generated in Makkah city annually. The collected MSW is disposed of in the landfills without any treatment or energy recovery. As a result, greenhouse gas (GHG) emissions and contamination of the soil and water bodies along with leachate and odors are occurring in waste disposal vicinities. The composition of MSW shows that food waste is the largest waste stream (up to 51%) of the total generated MSW. About 13% of the food waste consists of fat content that is equivalent to about 64 thousand tons per year. This study aims to estimate the production potential of biodiesel first time in Makkah city from fat/oil fractions of MSW and highlight its economic and environmental benefits. It has been estimated that 62.53, 117.15 and 6.38 thousand tons of biodiesel, meat and bone meal (MBM) and glycerol respectively could be produced in 2014. A total electricity potential of 852 Gigawatt hour (GWh) from all three sources based on their energy contents, Higher Heating Value (HHV) of 40.17, 18.33 and 19 MJ/kg, was estimated for 2014 that will increase up to 1777 GWh in 2050. The cumulative net savings from landfill waste diversion (256 to 533 million Saudi Riyal (SAR)), carbon credits (46 to 96 million SAR), fuel savings (146 to 303 million SAR) and electricity generation (273 to 569 million SAR) have a potential to add a total net revenue of 611 to 1274 million SAR every year to the Saudi economy, from 2014 to 2050 respectively. However, further studies including real-time data about annual slaughtering activities and the amount of waste generation and its management are critical to decide optimum waste management practices based on life cycle assessment (LCA) and life cycle costing (LCC) methodologies. PMID:28207856
Introduction to Voigt's wind power plant. [energy conversion efficiency
NASA Technical Reports Server (NTRS)
Tompkin, J.
1973-01-01
The design and operation of a 100 kilowatt wind driven generator are reported. Its high speed three-bladed turbine operates at a height of 50 meters. Blades are rigidly connected to the hub and turbine revolutions change linearly with wind velocity, maintaining a constant speed ratio of blade tip velocity to wind velocity over the full predetermined wind range. Three generators installed in the gondola generate either dc or ac current. Based on local wind conditions, the device has a maximum output of 720 kilowatts at a wind velocity of 16 meters per second. Total electrical capacity is 750 kilowatts, and power output per year is 2,135,000 kilowatt/hours.
The generation of pollution-free electrical power from solar energy.
NASA Technical Reports Server (NTRS)
Cherry, W. R.
1971-01-01
Projections of the U.S. electrical power demands over the next 30 years indicate that the U.S. could be in grave danger from power shortages, undesirable effluence, and thermal pollution. An appraisal of nonconventional methods of producing electrical power is conducted, giving particular attention to the conversion of solar energy into commercial quantities of electrical power by solar cells. It is found that 1% of the land area of the 48 states could provide the total electrical power requirements of the U.S. in the year 1990. The ultimate method of generating vast quantities of electrical power would be from a series of synchronous satellites which beam microwave power back to earth to be used wherever needed. Present high manufacturing costs of solar cells could be substantially reduced by using massive automated techniques employing abundant low cost materials.
NASA Astrophysics Data System (ADS)
Bhattacharjee, Subhadeep; Mohanta, Subhajit
2018-06-01
Biomass energy is one of the potential renewable energy sources which occupy 77% of the available natural resources of the world. In India, agro residues constitute a major part of the total annual production of the biomass resource. Rice is the major crop in India that leaves substantial quantity of straw in the field. 34% of rice straw residue produced in the country is surplus and is either left in the field as uncollected or to a large extent open-field burnt. Thus, the unutilized rice straw is found promising for heat and power generation either through incineration (direct combustion) or thermo chemical conversion. This present work envisages the comprehensive performative evaluation of a rice straw supported biomass incineration power plant mainly through plant performance characterization, plant economics, and co-firing issues with emission analysis.
NASA Astrophysics Data System (ADS)
Bhattacharjee, Subhadeep; Mohanta, Subhajit
2018-03-01
Biomass energy is one of the potential renewable energy sources which occupy 77% of the available natural resources of the world. In India, agro residues constitute a major part of the total annual production of the biomass resource. Rice is the major crop in India that leaves substantial quantity of straw in the field. 34% of rice straw residue produced in the country is surplus and is either left in the field as uncollected or to a large extent open-field burnt. Thus, the unutilized rice straw is found promising for heat and power generation either through incineration (direct combustion) or thermo chemical conversion. This present work envisages the comprehensive performative evaluation of a rice straw supported biomass incineration power plant mainly through plant performance characterization, plant economics, and co-firing issues with emission analysis.
High pulse rate high resolution optical radar system
NASA Technical Reports Server (NTRS)
Goss, W. C.; Burns, R. H.; Chi, K. (Inventor)
1973-01-01
The system is composed of an optical cavity with a laser and a mode locking means to build up an optical pulse. An optical switch is also provided within the cavity to convert the polarization of the optical pulse generated within the cavity. The optical switch comprises an electro-optical crystal driven by a time delayed driver circuit which is triggered by a coincident signal made from an optical pulse signal and a gating pulse signal. The converted optical pulse strikes a polarization sensitive prism and is deflected out of the cavity toward the pending target in the form of a pulse containing most of the optical energy generated by the laser in the pulse build-up period. After striking the target, the reflected energy is picked up by a transceiver with the total travel time of the pulse being recorded.
Biochemical production of bioenergy from agricultural crops and residue in Iran.
Karimi Alavijeh, Masih; Yaghmaei, Soheila
2016-06-01
The present study assessed the potential for biochemical conversion of energy stored in agricultural waste and residue in Iran. The current status of agricultural residue as a source of bioenergy globally and in Iran was investigated. The total number of publications in this field from 2000 to 2014 was about 4294. Iran ranked 21st with approximately 54 published studies. A total of 87 projects have been devised globally to produce second-generation biofuel through biochemical pathways. There are currently no second-generation biorefineries in Iran and agricultural residue has no significant application. The present study determined the amount and types of sustainable agricultural residue and oil-rich crops and their provincial distribution. Wheat, barley, rice, corn, potatoes, alfalfa, sugarcane, sugar beets, apples, grapes, dates, cotton, soybeans, rapeseed, sesame seeds, olives, sunflowers, safflowers, almonds, walnuts and hazelnuts have the greatest potential as agronomic and horticultural crops to produce bioenergy in Iran. A total of 11.33million tonnes (Mt) of agricultural biomass could be collected for production of bioethanol (3.84gigaliters (Gl)), biobutanol (1.07Gl), biogas (3.15billion cubic meters (BCM)), and biohydrogen (0.90BCM). Additionally, about 0.35Gl of biodiesel could be obtained using only 35% of total Iranian oilseed. The potential production capacity of conventional biofuel blends in Iran, environmental and socio-economic impacts including well-to-wheel greenhouse gas (GHG) emissions, and the social cost of carbon dioxide reduction are discussed. The cost of emissions could decrease up to 55.83% by utilizing E85 instead of gasoline. The possible application of gaseous biofuel in Iran to produce valuable chemicals and provide required energy for crop cultivation is also studied. The energy recovered from biogas produced by wheat residue could provide energy input for 115.62 and 393.12 thousand hectares of irrigated and rain-fed wheat cultivation in Iran, respectively. The nitrogen requirement for 33.6% of the total wheat cultivation area could be supplied by the ammonia acquired from biohydrogen. A discussion of the logistics of collection and transportation of the biomass and sensitivity analysis are carried out to evaluate the effect of field cover factor, crop yield, and well-to-wheel GHG emission on collectable residue, biofuel production, and GHG emissions. Copyright © 2016 Elsevier Ltd. All rights reserved.
Essays on restructured electricity markets
NASA Astrophysics Data System (ADS)
Nicholson, Emma Leah
This dissertation focuses on the performance of restructured electricity markets in the United States. In chapter 1, I study bidder-specific offer caps ("BSOCs") which are used to mitigate market power in three wholesale electricity markets. The price of electricity is determined through multi-unit uniform price auctions and BSOCs impose an upper limit, which is increasing in marginal cost, on each generator's bid. I apply BSOCs in both the uniform and discriminatory price auctions and characterize the equilibria in a two firm model with stochastic demand. BSOCs unambiguously increase expected production efficiency in the uniform price auction and they can increase the expected profit of the generator with the lower cap. Chapter 2, coauthored with Ramteen Sioshansi, Ph.D., compares two types of uniform price auction formats used in wholesale electricity markets, centrally committed markets and self committed markets. In centrally committed markets, generators submit two-part bids consisting of a fixed startup cost and a variable (per MWh) energy cost, and the auctioneer ensures that no generator operates at a loss. Generators in self committed markets must incorporate their startup costs into their one part energy bids. We derive Nash equilibria for both the centrally and self committed electricity markets in a model with two symmetric generators with nonconvex costs and deterministic demand. Using a numerical example, we demonstrate that if the caps on the bid elements are chosen appropriately, the two market designs are equivalent in terms of generator revenues and settlement costs. Regulators and prominent academic experts believe that electric restructuring polices have stifled investment in new generation capacity. In chapter 3 I seek to determine whether these fears are supported by empirical evidence. I examine both total investment in megawatts and the number of new investments across regions that adopted different electric restructuring policies to determine whether electric restructuring is associated with lower levels of investment in new generation capacity. The estimation results do not prove that total investment levels are lower in regions with restructured electric systems, but I cannot rule the possibility out.
Managing total corporate electricity/energy market risks
DOE Office of Scientific and Technical Information (OSTI.GOV)
Henney, A.; Keers, G.
1998-10-01
The banking industry has developed a tool kit of very useful value at risk techniques for hedging risk, but these techniques must be adapted to the special complexities of the electricity market. This paper starts with a short history of the use of value-at-risk (VAR) techniques in banking risk management and then examines the specific and, in many instances, complex risk management challenges faced by electric companies from the behavior of prices in electricity markets and from the character of generation and electric retailing risks. The third section describes the main methods for making VAR calculations along with an analysismore » of their suitability for analyzing the risks of electricity portfolios and the case for using profit at risk and downside risk as measures of risk. The final section draws the threads together and explains how to look at managing total corporate electricity market risk, which is a big step toward managing total corporate energy market risk.« less
Sensitivity of Regional Hydropower Generation to the Projected Changes in Future Watershed Hydrology
NASA Astrophysics Data System (ADS)
Kao, S. C.; Naz, B. S.; Gangrade, S.
2015-12-01
Hydropower is a key contributor to the renewable energy portfolio due to its established development history and the diverse benefits it provides to the electric power systems. With the projected change in the future watershed hydrology, including shift of snowmelt timing, increasing occurrence of extreme precipitation, and change in drought frequencies, there is a need to investigate how the regional hydropower generation may change correspondingly. To evaluate the sensitivity of watershed storage and hydropower generation to future climate change, a lumped Watershed Runoff-Energy Storage (WRES) model is developed to simulate the annual and seasonal hydropower generation at various hydropower areas in the United States. For each hydropower study area, the WRES model use the monthly precipitation and naturalized (unregulated) runoff as inputs to perform a runoff mass balance calculation for the total monthly runoff storage in all reservoirs and retention facilities in the watershed, and simulate the monthly regulated runoff release and hydropower generation through the system. The WRES model is developed and calibrated using the historic (1980-2009) monthly precipitation, runoff, and generation data, and then driven by a large set of dynamically- and statistically-downscaled Coupled Model Intercomparison Project Phase 5 climate projections to simulate the change of watershed storage and hydropower generation under different future climate scenarios. The results among different hydropower regions, storage capacities, emission scenarios, and timescales are compared and discussed in this study.
NASA Astrophysics Data System (ADS)
Amme, J.; Pleßmann, G.; Bühler, J.; Hülk, L.; Kötter, E.; Schwaegerl, P.
2018-02-01
The increasing integration of renewable energy into the electricity supply system creates new challenges for distribution grids. The planning and operation of distribution systems requires appropriate grid models that consider the heterogeneity of existing grids. In this paper, we describe a novel method to generate synthetic medium-voltage (MV) grids, which we applied in our DIstribution Network GeneratOr (DINGO). DINGO is open-source software and uses freely available data. Medium-voltage grid topologies are synthesized based on location and electricity demand in defined demand areas. For this purpose, we use GIS data containing demand areas with high-resolution spatial data on physical properties, land use, energy, and demography. The grid topology is treated as a capacitated vehicle routing problem (CVRP) combined with a local search metaheuristics. We also consider the current planning principles for MV distribution networks, paying special attention to line congestion and voltage limit violations. In the modelling process, we included power flow calculations for validation. The resulting grid model datasets contain 3608 synthetic MV grids in high resolution, covering all of Germany and taking local characteristics into account. We compared the modelled networks with real network data. In terms of number of transformers and total cable length, we conclude that the method presented in this paper generates realistic grids that could be used to implement a cost-optimised electrical energy system.
Thermal storage technologies for solar industrial process heat applications
NASA Technical Reports Server (NTRS)
Gordon, L. H.
1979-01-01
The state-of-the-art of thermal storage subsystems for the intermediate and high temperature (100 C to 600 C) solar industrial process heat generation is presented. Primary emphasis is focused on buffering and diurnal storage as well as total energy transport. In addition, advanced thermal storage concepts which appear promising for future solar industrial process heat applications are discussed.
Measuring Stability and Security in Iraq
2010-03-01
development, generating 27 signed investment licenses totaling $2 billion for the tourism and hospitality industries, with 13 projects under...continue to plan and execute the responsible drawdown of U.S. military forces from Iraq. By August 31, 2010, U.S. forces will have transitioned... planning and budgeting, procurement, and information technology. In summary, political, rule-of-law, economic and energy, and security trends in Iraq
NASA Astrophysics Data System (ADS)
Chaianong, A.; Bangviwat, A.; Menke, C.
2017-07-01
Driven by decreasing PV and energy storage prices, increasing electricity costs and policy supports from Thai government (self-consumption era), rooftop PV and energy storage systems are going to be deployed in the country rapidly that may disrupt existing business models structure of Thai distribution utilities due to revenue erosion and lost earnings opportunities. The retail rates that directly affect ratepayers (non-solar customers) are expected to increase. This paper focuses on a framework for evaluating impacts of PV with and without energy storage systems on Thai distribution utilities and ratepayers by using cost-benefit analysis (CBA). Prior to calculation of cost/benefit components, changes in energy sales need to be addressed. Government policies for the support of PV generation will also help in accelerating the rooftop PV installation. Benefit components include avoided costs due to transmission losses and deferring distribution capacity with appropriate PV penetration level, while cost components consist of losses in revenue, program costs, integration costs and unrecovered fixed costs. It is necessary for Thailand to compare total costs and total benefits of rooftop PV and energy storage systems in order to adopt policy supports and mitigation approaches, such as business model innovation and regulatory reform, effectively.
Lattice Truss Structural Response Using Energy Methods
NASA Technical Reports Server (NTRS)
Kenner, Winfred Scottson
1996-01-01
A deterministic methodology is presented for developing closed-form deflection equations for two-dimensional and three-dimensional lattice structures. Four types of lattice structures are studied: beams, plates, shells and soft lattices. Castigliano's second theorem, which entails the total strain energy of a structure, is utilized to generate highly accurate results. Derived deflection equations provide new insight into the bending and shear behavior of the four types of lattices, in contrast to classic solutions of similar structures. Lattice derivations utilizing kinetic energy are also presented, and used to examine the free vibration response of simple lattice structures. Derivations utilizing finite element theory for unique lattice behavior are also presented and validated using the finite element analysis code EAL.
The drivers to adopt renewable energy among residential users.
NASA Astrophysics Data System (ADS)
Rahman, Zahari Abdul; Elinda, Esa
2016-03-01
This study aims to examine the drivers to adopt renewable energy (RE) among residential users in Malaysia. Based on the theoretical framework of a consumer’s decision making process, an empirical study of the adoption of RE was conducted. A total of 501 residential users were used in this study. This study proved that perceived utility of new technology, perceived utility of new service, and perceived benefit of new technology are the drivers to adopt RE among residential users. These factors are knowing crucial to RE suppliers and producers because it will generates more demand from the residential users and the percentage of energy mix from RE sources can be increase.
Vigeolas, Helene; Hühn, Daniela; Geigenberger, Peter
2011-01-01
Nonsymbiotic hemoglobins are ubiquitously expressed in plants and divided into two different classes based on gene expression pattern and oxygen-binding properties. Most of the published research has been on the function of class 1 hemoglobins. To investigate the role of class 2 hemoglobins, transgenic Arabidopsis (Arabidopsis thaliana) plants were generated overexpressing Arabidopsis hemoglobin-2 (AHb2) under the control of a seed-specific promoter. Overexpression of AHb2 led to a 40% increase in the total fatty acid content of developing and mature seeds in three subsequent generations. This was mainly due to an increase in the polyunsaturated C18:2 (ω-6) linoleic and C18:3 (ω-3) α-linolenic acids. Moreover, AHb2 overexpression led to an increase in the C18:2/C18:1 and C18:3/C18:2 ratios as well as in the C18:3 content in mol % of total fatty acids and in the unsaturation/saturation index of total seed lipids. The increase in fatty acid content was mainly due to a stimulation of the rate of triacylglycerol synthesis, which was attributable to a 3-fold higher energy state and a 2-fold higher sucrose content of the seeds. Under low external oxygen, AHb2 overexpression maintained an up to 5-fold higher energy state and prevented fermentation. This is consistent with AHb2 overexpression results in improved oxygen availability within developing seeds. In contrast to this, overexpression of class 1 hemoglobin did not lead to any significant increase in the metabolic performance of the seeds. These results provide evidence for a specific function of class 2 hemoglobin in seed oil production and in promoting the accumulation of polyunsaturated fatty acids by facilitating oxygen supply in developing seeds. PMID:21205621
Stability of boundary layer flow based on energy gradient theory
NASA Astrophysics Data System (ADS)
Dou, Hua-Shu; Xu, Wenqian; Khoo, Boo Cheong
2018-05-01
The flow of the laminar boundary layer on a flat plate is studied with the simulation of Navier-Stokes equations. The mechanisms of flow instability at external edge of the boundary layer and near the wall are analyzed using the energy gradient theory. The simulation results show that there is an overshoot on the velocity profile at the external edge of the boundary layer. At this overshoot, the energy gradient function is very large which results in instability according to the energy gradient theory. It is found that the transverse gradient of the total mechanical energy is responsible for the instability at the external edge of the boundary layer, which induces the entrainment of external flow into the boundary layer. Within the boundary layer, there is a maximum of the energy gradient function near the wall, which leads to intensive flow instability near the wall and contributes to the generation of turbulence.
Lessons that non-scientists can teach us about the concept of energy: a human-centred approach
NASA Astrophysics Data System (ADS)
Leggett, Monica
2003-03-01
Energy is not only a core concept in physics but also a major issue in our post-Kyoto world. When using a constructivist approach to teaching, we need to be aware of students' preconceptions. A palette of alternative frameworks, which includes those used by adults within the community, can facilitate this. An exploration of energy issues with non-scientists within the community has generated some relevant insights. Participants' concepts of energy were multifaceted. Most had a strong personal component, but also social, technical and cosmic dimensions. Although many participants were uncomfortable with the terms `renewable' and `sustainable', they clearly articulated the social and technical requirements for a shift away from current fossil fuel dependency. However, the law of conservation of energy, a core belief of physicists, appeared to be totally absent from their concept of energy.
Data feature: 1996 world nuclear electricity production
DOE Office of Scientific and Technical Information (OSTI.GOV)
NONE
1997-12-01
Detailed data on electricity supplied by nuclear power reactors in 1996 are provided. Figures from the International Atomic Energy Agency indicate that a total of 32 countries worldwide were operating 441 nuclear power plants with an installed capacity of 350,411 GWe, and that 36 commercial nuclear power plant units in 14 different countries with an aggregate installed capacity of 27,928 GWe were under construction. Worldwide nuclear generated electricity increased by 3.6% from 1995 to 1996, providing 17.3% of the world`s electricity production. Data for individual countries and regional totals, including generation and consumption data by source, are provided for Westernmore » Europe, Eastern Europe, the Commonwealth of Independent States, the Far East, Canada, and the United States. Other information provided includes 1996 commercial startups, decommissioning, reactor load factors, imports and exports, and gross electricity production.« less
Federal Register 2010, 2011, 2012, 2013, 2014
2012-09-14
... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Project No. 2280-015] FirstEnergy Generation Corporation, FirstEnergy Generation, LLC; Notice of Application for Transfer of License, and Soliciting Comments and Motions To Intervene On July 6, 2012, FirstEnergy Generation Corporation (transferor...
A multilayered approach to superconducting tunnel junction x ray detectors
NASA Technical Reports Server (NTRS)
Rippert, E. D.; Song, S. N.; Ketterson, J. B.; Maglic, S. R.; Lomatch, S.; Thomas, C.; Cheida, M. A.; Ulmer, M. P.
1992-01-01
'First generation' superconducting tunnel junction X-ray detectors (characterized by a single tunnel junction in direct contact with its substrate, with totally external amplification) remain more than an order of magnitude away from their theoretical energy resolutions which are in the order of eV's. The difficulties that first generation devices are encountering are being attacked by a 'second generation' of superconducting X-ray detector designs including quasiparticle trapping configurations and Josephson junction arrays. A second generation design concept, the multilayered superconducting tunnel junction X-ray detector, consisting of tens to hundreds of tunnel junctions stacked on top of one another (a superlattice), is presented. Some of the possibilities of this engineered materials approach include the tuning of phonon transmission characteristics of the material, suppression of parasitic quasiparticle trapping and intrinsic amplification.
Aburto, Tania C; Pedraza, Lilia S; Sánchez-Pimienta, Tania G; Batis, Carolina; Rivera, Juan A
2016-09-01
Overweight and obesity prevalences in Mexico are among the highest in the world, with dietary factors being the third-leading category of risk contributing to the burden of disease. Consequently, studying the compliance of the Mexican population to food-based dietary recommendations is essential for informing nutritional policies. We described the energy contribution of food groups to total dietary energy intake of the Mexican population and by sociodemographic subgroups and compared these results with Mexican dietary recommendations. Twenty-four-hour dietary recalls for participants aged ≥5 y (n = 7983) from the 2012 Mexican National Health and Nutrition Survey were used. Foods and beverages were classified into 8 groups (the first 6 were called "basic foods" and the last 2 "discretionary foods"), as follows: 1) cereals, 2) legumes, 3) milk and dairy, 4) meat and animal products, 5) fruit and vegetables, 6) fats and oils, 7) sugar-sweetened beverages (SSBs), and 8) products high in saturated fat and/or added sugar (HSFAS). Recommendations were based on the Mexican Dietary Guidelines (MDG). Energy contributions from the food groups by age, sex, region, residence (rural or urban), and socioeconomic status (SES) were estimated. The highest contribution to total energy intake came from cereals (33%) followed by HSFAS (16%), meat and animal products (14%), and SSBs (9.8%). Fruit and vegetables (5.7%) and legumes (3.8%) had the lowest contribution. Energy contribution of several food groups differed significantly between population subgroups. Overall, discretionary foods contributed more than one-quarter of total energy intake (26%) and were 13 percentage points above the maximum allowed by the recommendations, whereas the intakes of legumes and fruit and vegetables were much lower than recommended. Our results show the need to generate a food environment conducive to a healthier diet in the Mexican population. © 2016 American Society for Nutrition.
Particulate Emission Abatement for Krakow Boilerhouses
DOE Office of Scientific and Technical Information (OSTI.GOV)
NONE
1998-09-14
Environmental cleanup and pollution control are considered the foremost national priorities in Poland. The target of this cleanup is the Polish coal industry, which supplies the fuel to generate over 78% of Poland`s primary energy production. This project addresses the problem of airborne dust and uncontrolled particulate emissions from boilerhouses, which represent a large fraction of the total in Poland. In Krakow alone, there are numerous uncontrolled boilers accounting for about half the total fuel use. The large number of low-capacity boilers poses both technical and economic challenges, since the cost of control equipment is a significant factor in themore » reduction of emissions. A new concept in dust collection, called a Core Separator, is proposed for this important application. The Core Separator is an advanced technology developed through research sponsored by the Department of Energy.« less
Search for X rays from the planet Jupiter.
NASA Technical Reports Server (NTRS)
Hurley, K. C.
1972-01-01
Actively collimated balloon-borne scintillation counters employing a special phoswich anticoincidence technique were flown a total of 5 times from Palestine, Texas. Jupiter was observed for a total of 133 min, and an upper limit to the flux of X rays present at the observation time is .016 X rays/sq cm sec in the energy range 30-100 keV. Three separate calculations are made to estimate the flux of Jovian X rays at the earth. These estimates range from .000000001 to .1 X rays/sq cm sec in the energy range 30-100 keV. It is concluded that, since there was no decametric emission at the time of the flight and there had been no significant solar activity for several days prior to the flight, no X rays were being generated at the time of the observation.
NASA Astrophysics Data System (ADS)
Shrestha, Ishor Kumar
The studies of hard x-ray (HXR) emission and electron beam generation in Z-pinch plasmas are very important for Inertial Confinement Fusion (ICF) research and HXR emission application for sources of K-shell and L-shell radiation. Energetic electron beams from Z-pinch plasmas are potentially a problem in the development of ICF. The electron beams and the accompanying HXR emission can preheat the fuel of a thermonuclear target, thereby preventing the fuel compression from reaching densities required for the ignition of a fusion reaction. The photons above 3-4 keV radiated from a Z pinch can provide detailed information about the high energy density plasmas produced at stagnation. Hence, the investigation of characteristics of hard x-rays and electron beams produced during implosions of wire array loads on university scale-generators may provide important data for future ICF, sources of K-shell and L-shell radiations and basic plasma research. This dissertation presents the results of experimental studies of HXR and electron beam generation in wire-array and X-pinch on the 1.7 MA, 100-ns current rise time Zebra generator at University of Nevada, Reno and 1-MA 100-ns current rise-time Cornell Beam Research Accelerator (COBRA) at Cornell University. The experimental study of characteristics of HXR produced by multi-planar wire arrays, compact cylindrical wire array (CCWA) and nested cylindrical wire array (NCWA) made from Al, Cu, Mo, Ag, W and Au were analyzed. The dependence of the HXR yield and power on geometry of the load, the wire material, and load mass was observed. The presence of aluminum wires in the load with the main material such as stainless steel, Cu, Mo, Ag, W or Au in combined wire array decreases HXR yield. The comparison of emission characteristics of HXR and generation of electron beams in CCWA and NCWA on both the high impedance Zebra generator and low impedance COBRA generator were investigated. Some of the "cold" K- shell spectral lines (0.7-2.3Á) and cold L-shell spectral lines (1-1.54Á) in the HXR region were observed only during the interaction of electron beam with load material and anode surface. These observations suggest that the mechanism of HXR emission should be associated with non-thermal mechanisms such as the interaction of the electron beam with the load material. In order to estimate the characteristics of the high-energetic electron beam in Z-pinch plasmas, a hard x-ray polarimeter (HXP) has been developed and used in experiments on the Zebra generator. The electron beams (energy more than 30keV) have been investigated with measurements of the polarization state of the emitted bremsstrahlung radiation from plasma. We also analyzed characteristics of energetic electron beams produced by implosions of multi-planar wire arrays, compact cylindrical and nested wire arrays as well as X-pinches. Direct indications of electron beams (electron cutoff energy EB from 42-250 keV) were obtained by using the measured current of a Faraday cup placed above the anode or mechanical damage observed in the anode surface. A comparison of total electron beam energy and the spatial and spectral analysis of the parameters of plasmas were investigated for different wire materials. The dependences of the total electron beam energy (E b) on the wire material and the geometry of the wire array load were studied.
Xin, Mei-Ling; Yang, Jia-Wen; Li, Yu
2017-07-11
The reaction pathways of PCB-77 in the atmosphere with ·OH, O 2 , NO x , and 1 O 2 were inferred based on density functional theory calculations with the 6-31G* basis set. The structures the reactants, transition states, intermediates, and products were optimized. The energy barriers and reaction heats were obtained to determine the energetically favorable reaction pathways. To study the solvation effect, the energy barriers and reaction rates for PCB-77 with different polar and nonpolar solvents (cyclohexane, benzene, carbon tetrachloride, chloroform, acetone, dichloromethane, ethanol, methanol, acetonitrile, dimethylsulfoxide, and water) were calculated. The results showed that ·OH preferentially added to the C5 atom of PCB-77, which has no Cl atom substituent, to generate the intermediate IM5. This intermediate subsequently reacted with O 2 via pathway A to generate IM5a, with an energy barrier of 7.27 kcal/mol and total reaction rate of 8.45 × 10 -8 cm 3 /molecule s. Pathway B involved direct dehydrogenation of IM5 to produce the OH-PCBs intermediate IM5b, with an energy barrier of 28.49 kcal/mol and total reaction rate of 1.15 × 10 -5 cm 3 /molecule s. The most likely degradation pathway of PCB-77 in the atmosphere is pathway A to produce IM5a. The solvation effect results showed that cyclohexane, carbon tetrachloride, and benzene could reduce the reaction energy barrier of pathway A. Among these solvents, the solvation effect of benzene was the largest, and could reduce the total reaction energy barrier by 25%. Cyclohexane, carbon tetrachloride, benzene, dichloromethane, acetone, and ethanol could increase the total reaction rate of pathway A. The increase in the reaction rate of pathway A with benzene was 8%. The effect of solvents on oxidative degradation of PCB-77 in the atmosphere is important. Graphical abstract The reaction pathways of PCB-77 in the atmosphere with •OH, O2, NOx, and 1O2 were inferred based on density functional theory calculations with the 6-31G* basis set. Different polar and nonpolar solvents: cyclohexane, benzene, carbon tetrachloride, chloroform, acetone, dichloromethane, ethanol, methanol, acetonitrile, dimethylsulfoxide, and water were selected to study the solvation effect on the favorable reaction pathways. The investigated results showed what kind of pathway was most likely to occur and the solvent effect on the reaction pathway.
Manufacturing and testing of a magnetically suspended composite flywheel energy storage system
NASA Technical Reports Server (NTRS)
Wells, Stephen; Pang, Da-Chen
1994-01-01
This paper presents the work performed to develop a multiring composite material flywheel and improvements of a magnetically suspended energy storage system. The flywheel is constructed of filament would graphite/epoxy and is interference assembled for better stress distribution to obtain higher speeds. The stationary stack in the center of the disk supports the flywheel with two magnetic bearings and provides power transfer to the flywheel with a motor/generator. The system operates under a 10(exp -4) torr environment and has been demonstrated to 20,000 rpm with a total stored energy of 15.9 Wh. When this flywheel cycles between its design speeds (45,000 to 90,000 rpm), it will deliver 242 Wh and have a usable specific energy density of 42.6 Wh/kg.
Potential of Solar Energy in Kota Kinabalu, Sabah: An Estimate Using a Photovoltaic System Model
NASA Astrophysics Data System (ADS)
Markos, F. M.; Sentian, J.
2016-04-01
Solar energy is becoming popular as an alternative renewable energy to conventional energy source, particularly in the tropics, where duration and intensity of solar radiation are longer. This study is to assess the potential of solar energy generated from solar for Kota Kinabalu, a rapidly developing city in the State of Sabah, Malaysia. A year data of solar radiation was obtained using pyranometer, which was located at Universiti Malaysia Sabah (6.0367° N, 116.1186° E). It was concluded that the annual average solar radiation received in Kota Kinabalu was 182 W/m2. In estimating the potential energy generated from solar for Kota Kinabalu city area, a photovoltaic (PV) system model was used. The results showed that, Kota Kinabalu is estimated to produce 29,794 kWh/m2 of electricity from the solar radiation received in a year. This is equivalent to 0.014 MW of electricity produced just by using one solar panel. Considering the power demand in Sabah by 2020 is 1,331 MW, this model showed that the solar energy can contribute around 4% of energy for power demand, with 1 MW capacity of the PV system. 1 MW of PV system installation will require about 0.0328% from total area of the city. This assessment could suggest that, exploration for solar power energy as an alternative source of renewable energy in the city can be optimised and designed to attain significant higher percentage of contribution to the energy demand in the state.
Albert, J-D; Meadeb, J; Guggenbuhl, P; Marin, F; Benkalfate, T; Thomazeau, H; Chalès, G
2007-03-01
In a prospective randomised trial of calcifying tendinitis of the rotator cuff, we compared the efficacy of dual treatment sessions delivering 2500 extracorporeal shock waves at either high- or low-energy, via an electromagnetic generator under fluoroscopic guidance. Patients were eligible for the study if they had more than a three-month history of calcifying tendinitis of the rotator cuff, with calcification measuring 10 mm or more in maximum dimension. The primary outcome measure was the change in the Constant and Murley Score. A total of 80 patients were enrolled (40 in each group), and were re-evaluated at a mean of 110 (41 to 255) days after treatment when the increase in Constant and Murley score was significantly greater (t-test, p = 0.026) in the high-energy treatment group than in the low-energy group. The improvement from the baseline level was significant in the high-energy group, with a mean gain of 12.5 (-20.7 to 47.5) points (p < 0.0001). The improvement was not significant in the low-energy group. Total or subtotal resorption of the calcification occurred in six patients (15%) in the high-energy group and in two patients (5%) in the low-energy group. High-energy shock-wave therapy significantly improves symptoms in refractory calcifying tendinitis of the shoulder after three months of follow-up, but the calcific deposit remains unchanged in size in the majority of patients.
NASA Astrophysics Data System (ADS)
Adhikari, L.; Zank, G. P.; Hunana, P.; Hu, Q.
2016-12-01
Shocks are thought to be responsible for the amplification of turbulence as well as for generating turbulence throughout the heliosphere. We study the interaction of turbulence with parallel and perpendicular shock waves using the six-coupled-equation turbulence transport model of Zank et al. We model a 1D stationary shock wave using a hyperbolic tangent function and the Rankine-Hugoniot conditions for both a reduced model with four coupled equations and the full model. Eight quasi-parallel and five quasi-perpendicular events in the WIND spacecraft data sets are identified, and we compute the fluctuating magnetic and kinetic energy, the energy in forward and backward propagating modes, the total turbulent energy, the normalized residual energy, and the normalized cross helicity upstream and downstream of the observed shocks. We compare the observed fitted values upstream and downstream of the shock with numerical solutions to our model equations. The comparison shows that our theoretical results are in reasonable agreement with observations for both quasi-parallel and perpendicular shocks. We find that (1) the total turbulent energy, the energy in forward and backward propagating modes, and the normalized residual energy increase across the shock, (2) the normalized cross helicity increases or decreases across the shock, and (3) the correlation length increases upstream and downstream of the shock, and slightly flattens or decreases across the shock.
Biomass resources in California
DOE Office of Scientific and Technical Information (OSTI.GOV)
Tiangco, V.M.; Sethi, P.S.
1993-12-31
The biomass resources in California which have potential for energy conversion were assessed and characterized through the project funded by the California Energy Commission and the US Department of Energy`s Western Regional Biomass Energy Program (WRBEP). The results indicate that there is an abundance of biomass resources as yet untouched by the industry due to technical, economic, and environmental problems, and other barriers. These biomass resources include residues from field and seed crops, fruit and nut crops, vegetable crops, and nursery crops; food processing wastes; forest slash; energy crops; lumber mill waste; urban wood waste; urban yard waste; livestock manure;more » and chaparral. The estimated total potential of these biomass resource is approximately 47 million bone dry tons (BDT), which is equivalent to 780 billion MJ (740 trillion Btu). About 7 million BDT (132 billion MJ or 124 trillion Btu) of biomass residue was used for generating electricity by 66 direct combustion facilities with gross capacity of about 800 MW. This tonnage accounts for only about 15% of the total biomass resource potential identified in this study. The barriers interfering with the biomass utilization both in the on-site harvesting, collection, storage, handling, transportation, and conversion to energy are identified. The question whether these barriers present significant impact to biomass {open_quotes}availability{close_quotes} and {open_quotes}sustainability{close_quotes} remains to be answered.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Adhikari, L.; Zank, G. P.; Hunana, P.
Shocks are thought to be responsible for the amplification of turbulence as well as for generating turbulence throughout the heliosphere. We study the interaction of turbulence with parallel and perpendicular shock waves using the six-coupled-equation turbulence transport model of Zank et al. We model a 1D stationary shock wave using a hyperbolic tangent function and the Rankine–Hugoniot conditions for both a reduced model with four coupled equations and the full model. Eight quasi-parallel and five quasi-perpendicular events in the WIND spacecraft data sets are identified, and we compute the fluctuating magnetic and kinetic energy, the energy in forward and backwardmore » propagating modes, the total turbulent energy, the normalized residual energy, and the normalized cross helicity upstream and downstream of the observed shocks. We compare the observed fitted values upstream and downstream of the shock with numerical solutions to our model equations. The comparison shows that our theoretical results are in reasonable agreement with observations for both quasi-parallel and perpendicular shocks. We find that (1) the total turbulent energy, the energy in forward and backward propagating modes, and the normalized residual energy increase across the shock, (2) the normalized cross helicity increases or decreases across the shock, and (3) the correlation length increases upstream and downstream of the shock, and slightly flattens or decreases across the shock.« less
Electric Power Quarterly, October-December 1985. [Glossary
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
1986-05-05
The Electric Power Quarterly (EPQ) provides information on electric utilities at the plant level. The information concerns the following: cost, quantity, and quality of fossil fuel receipts; net generation; fuel consumption; and fuel stocks. The EPQ contains monthly data and quarterly totals for the reporting quarter. Data collected on Form EIA-759 regarding electric utilities' net generation, fuel consumption, and fuel stocks are presented on a plant-by-plant basis. In addition, quantity, cost, and quality of fossil fuel receipts collected on the Federal Energy Regulatory Commission (FERC) Form 423 are presented on a plant-by-plant basis.
Electric Power Quarterly, January-March 1986
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
1986-07-21
The ''Electric Power Quarterly (EPQ)'' provides information on electric utilities at the plant level. The information concerns the following: cost, quantity, and quality of fossil fuel receipts; net generation; fuel consumption; and fuel stocks. The ''EPQ'' contains monthly data and quarterly totals for the reporting quarter. In this report, data collected on Form EIA-759 regarding electric utilities' net generation, fuel consumption, and fuel stocks are presented on a plant-by-plant basis. In addition, quantity, cost, and quality of fossil fuel receipts collected on the Federal Energy Regulatory Commission (FERC) Form 423 are presented on a plant-by-plant basis.
Okeniyi, Joshua O; Atayero, Aderemi A; Popoola, Segun I; Okeniyi, Elizabeth T; Alalade, Gbenga M
2018-04-01
This data article presents comparisons of energy generation costs from gas-fired turbine and diesel-powered systems of distributed generation type of electrical energy in Covenant University, Ota, Nigeria, a smart university campus driven by Information and Communication Technologies (ICT). Cumulative monthly data of the energy generation costs, for consumption in the institution, from the two modes electric power, which was produced at locations closed to the community consuming the energy, were recorded for the period spanning January to December 2017. By these, energy generation costs from the turbine system proceed from the gas-firing whereas the generation cost data from the diesel-powered generator also include data on maintenance cost for this mode of electrical power generation. These energy generation cost data that were presented in tables and graphs employ descriptive probability distribution and goodness-of-fit tests of statistical significance as the methods for the data detailing and comparisons. Information details from this data of energy generation costs are useful for furthering research developments and aiding energy stakeholders and decision-makers in the formulation of policies on energy generation modes, economic valuation in terms of costing and management for attaining energy-efficient/smart educational environment.
U.S. Geological Survey—Energy and wildlife research annual report for 2017
Khalil, Mona
2017-09-08
IntroductionTerrestrial and aquatic ecosystems provide valuable services to humans and are a source of clean water, energy, raw materials, and productive soils. The Nation’s food supply is more secure because of wildlife. For example, native pollinators enhance agricultural crops, and insect-eating bats provide pest control services worth billions of dollars to farmers annually. Fish and wildlife are also vital to a vibrant outdoor recreation and tourism industry. Recreational activities, such as hunting, shooting, boating, and angling, generated \\$1.1 billion in excise taxes paid to State wildlife agencies in 2017. National parks, wildlife refuges, and monuments accounted for $35 billion in economic output and 318,000 jobs nationwide in 2016. Additional economic benefits are generated from the use and enjoyment of wildlife in State-owned lands and waters.Although the United States is rich in natural resources, human activity continues to place new pressures on fish and wildlife and the habitats they rely on. The United States became the world’s top producer of petroleum and natural gas products in 2012, surpassing Russia’s natural gas production levels in 2009 and Saudi Arabia’s petroleum production in 2013. The U.S. Energy Information Administration projects that the demand for liquid fuel, natural gas, and renewable energy will show strong growth in the next 20 years. Wind energy has demonstrated consistent growth since 2007 with now more than 53,000 wind turbines contributing to power grids in 41 States, Guam, and Puerto Rico. Solar energy has seen rapid growth since 2013 and made up nearly one-third of the total electricity generation additions in 2016. Yet as our Nation works to advance energy security and sustain wildlife, some conflicts have surfaced. Impacts of an expanding energy infrastructure include fragmentation and loss of habitat as well as mortality of birds, bats, fish, and other animals from interactions with energy generation facilities. Because energy development can often occur in wildlife habitats, ecological science can help guide project siting and operational decisions to areas that present the lowest risk to wildlife and energy developers.To address these challenges and make the most of new opportunities, the U.S. Geological Survey is producing innovative science to develop workable solutions that can help sustain wildlife and the habitat they rely upon, while allowing informed development.
Linked gas chromatograph-thermal energy analyzer/ion trap mass spectrometer
DOE Office of Scientific and Technical Information (OSTI.GOV)
Alcaraz, A.; Martin, W.H.; Andresen, B.D.
1991-05-01
The capability of comparing a nitrogen chromatogram generated from a gas chromatograph (GC, Varian model 3400) linked to a thermal energy analyzer (TEA, Thermedics Inc. Model 610) with a total ion chromatogram (from a Finnigan-MAT Ion Trap Mass Spectrometer, ITMS) has provided a new means to screen and identifying trace levels of nitrogen-containing compounds in complex mixtures. Prior to the work described here, it has not been possible to simultaneously acquire TEA and MS data. What was needed was a viable GC-TEA/ITMS interface to combine the capabilities of both instruments. 4 figs.
Analysis and design of an ultrahigh temperature hydrogen-fueled MHD generator
NASA Technical Reports Server (NTRS)
Moder, Jeffrey P.; Myrabo, Leik N.; Kaminski, Deborah A.
1993-01-01
A coupled gas dynamics/radiative heat transfer analysis of partially ionized hydrogen, in local thermodynamic equilibrium, flowing through an ultrahigh temperature (10,000-20,000 K) magnetohydrodynamic (MHD) generator is performed. Gas dynamics are modeled by a set of quasi-one-dimensional, nonlinear differential equations which account for friction, convective and radiative heat transfer, and the interaction between the ionized gas and applied magnetic field. Radiative heat transfer is modeled using nongray, absorbing-emitting 2D and 3D P-1 approximations which permit an arbitrary variation of the spectral absorption coefficient with frequency. Gas dynamics and radiative heat transfer are coupled through the energy equation and through the temperature- and density-dependent absorption coefficient. The resulting nonlinear elliptic problem is solved by iterative methods. Design of such MHD generators as onboard, open-cycle, electric power supplies for a particular advanced airbreathing propulsion concept produced an efficient and compact 128-MWe generator characterized by an extraction ratio of 35.5 percent, a power density of 10,500 MWe/cu m, and a specific (extracted) energy of 324 MJe/kg of hydrogen. The maximum wall heat flux and total wall heat load were 453 MW/sq m and 62 MW, respectively.
Design and process integration of organic Rankine cycle utilizing biomass for power generation
NASA Astrophysics Data System (ADS)
Ependi, S.; Nur, T. B.
2018-02-01
Indonesia has high potential biomass energy sources from palm oil mill industry activities. The growing interest on Organic Rankine Cycle (ORC) application to produce electricity by utilizing biomass energy sources are increasingly due to its successfully used for generating electricity from rejected waste heat to the environment in industrial processes. In this study, the potential of the palm oil empty fruit bunch, and wood chip have been used as fuel for biomass to generate electricity based ORC with combustion processes. The heat from combustion burner was transfer by thermal oil heater to evaporate ORC working fluid in the evaporator unit. The Syltherm-XLT thermal oil was used as the heat carrier from combustion burner, while R245fa was used as the working fluid for ORC unit. Appropriate designs integration from biomass combustion unit to ORC unit have been analyzed and proposed to generate expander shaft-work. Moreover, the effect of recuperator on the total system efficiency has also been investigated. It was observed that the fuel consumption was increased when the ORC unit equipped recuperator operated until certain pressure and decreased when operated at high pressure.
Maximizing photovoltaic power generation of a space-dart configured satellite
NASA Astrophysics Data System (ADS)
Lee, Dae Young; Cutler, James W.; Mancewicz, Joe; Ridley, Aaron J.
2015-06-01
Many small satellites are power constrained due to their minimal solar panel area and the eclipse environment of low-Earth orbit. As with larger satellites, these small satellites, including CubeSats, use deployable power arrays to increase power production. This presents a design opportunity to develop various objective functions related to energy management and methods for optimizing these functions over a satellite design. A novel power generation model was created, and a simulation system was developed to evaluate various objective functions describing energy management for complex satellite designs. The model uses a spacecraft-body-fixed spherical coordinate system to analyze the complex geometry of a satellite's self-induced shadowing with computation provided by the Open Graphics Library. As an example design problem, a CubeSat configured as a space-dart with four deployable panels is optimized. Due to the fast computation speed of the solution, an exhaustive search over the design space is used to find the solar panel deployment angles which maximize total power generation. Simulation results are presented for a variety of orbit scenarios. The method is extendable to a variety of complex satellite geometries and power generation systems.
NASA Astrophysics Data System (ADS)
Linden, H. R.; Singer, S. F.
2001-12-01
It is generally agreed that hydrogen is an ideal energy source, both for transportation and for the generation of electric power. Through the use of fuel cells, hydrogen becomes a high-efficiency carbon-free power source for electromotive transport; with the help of regenerative braking, cars should be able to reach triple the current mileage. Many have visualized a distributed electric supply network with decentralized generation based on fuel cells. Fuel cells can provide high generation efficiencies by overcoming the fundamental thermodynamic limitation imposed by the Carnot cycle. Further, by using the heat energy of the high-temperature fuel cell in co-generation, one can achieve total thermal efficiencies approaching 100 percent, as compared to present-day average power-plant efficiencies of around 35 percent. In addition to reducing CO2 emissions, distributed generation based on fuel cells also eliminates the tremendous release of waste heat into the environment, the need for cooling water, and related limitations on siting. Manufacture of hydrogen remains a key problem, but there are many technical solutions that come into play whenever the cost equations permit . One can visualize both central and local hydrogen production. Initially, reforming of abundant natural gas into mixtures of 80% H2 and 20% CO2 provides a relatively low-emission source of hydrogen. Conventional fossil-fuel plants and nuclear plants can become hydrogen factories using both high-temperature topping cycles and electrolysis of water. Hydro-electric plants can manufacture hydrogen by electrolysis. Later, photovoltaic and wind farms could be set up at favorable locations around the world as hydrogen factories. If perfected, photovoltaic hydrogen production through catalysis would use solar photons most efficiently . For both wind and PV, hydrogen production solves some crucial problems: intermittency of wind and of solar radiation, storage of energy, and use of locations that are not desirable for other economic uses. A hydrogen-based energy future is inevitable as low-cost sources of petroleum and natural gas become depleted with time. However, such fundamental changes in energy systems will take time to accomplish. Coal may survive for a longer time but may not be able to compete as the century draws to a close.
Implications of Outside-the-Box Technologies on Future Space Exploration and Colonization
NASA Astrophysics Data System (ADS)
Loder, Theodore C.
2003-01-01
In general, planning for future manned space exploration either to the moon, Mars, or an asteroid has depended on a somewhat linear extrapolation of our present technologies. Two major prohibitive cost issues regarding such planning are payload lift and in-flight energy generation. The costs of these in both engineering and actual flight costs, coupled with the planning necessary to carry out such exploration have prevented us from actively moving forward. Although, it will be worthwhile to continue to plan for such exploration using ``present'' technologies, I recommend that planning be concerned mainly with mission strategies and goals utilizing both present technology and totally new energy breakthroughs. There are presently in research and development an entire suite of relevant outside-the-box technologies which will include both zero point energy generation and antigravity technologies that will replace our present solar/nuclear/fuel cell energy technologies and liquid/solid fuel rockets. This paper describes some of these technologies, the physics behind them and their potential use for manned space exploration. The companies and countries that first incorporate these technologies into their space programs will lead the way in exploring and colonizing space.
NASA Astrophysics Data System (ADS)
Crespillo, M. L.; Agulló-López, F.; Zucchiatti, A.
2017-03-01
An extensive survey for the formation energies of Frenkel pairs, as representative candidates for radiation-induced point defects, is presented and discussed in relation to the cumulative mechanisms (CM) of track formation in dielectric materials under swift heavy ion (SHI) irradiation. These mechanisms rely on the generation and accumulation of point defects during irradiation followed by collapse of the lattice once a threshold defect concentration is reached. The physical basis of those approaches has been discussed by Fecht as a defect-assisted transition to an amorphous phase. Although a first quantitative analysis of the CM model was previously performed for LiNbO3 crystals, we have, here, adopted a broader phenomenological approach. It explores the correlation between track formation thresholds and the energies for Frenkel pair formation for a broad range of materials. It is concluded that the threshold stopping powers can be roughly scaled with the energies required to generate a critical Frenkel pair concentration in the order of a few percent of the total atomic content. Finally, a comparison with the predictions of the thermal spike model is discussed within the analytical Szenes approximation.
Electric motorcycle charging station powered by solar energy
NASA Astrophysics Data System (ADS)
Siriwattanapong, Akarawat; Chantharasenawong, Chawin
2018-01-01
This research proposes a design and verification of an off-grid photovoltaic system (PVS) for electric motorcycle charging station to be located in King’s Mongkut’s University of Technology Thonburi, Bangkok, Thailand. The system is designed to work independently (off-grid) and it must be able to fully charge the batteries of a typical passenger electric motorcycle every evening. A 1,000W Toyotron electric motorcycle is chosen for this study. It carries five units of 12.8V 20Ah batteries in series; hence its maximum energy requirement per day is 1,200Wh. An assessment of solar irradiation data and the Generation Factor in Bangkok, Thailand suggests that the charging system consists of one 500W PV panel, an MPPT charge controller, 48V 150Ah battery, a 1,000W DC to AC inverter and other safety devices such as fuses and breakers. An experiment is conducted to verify the viability of the off-grid PVS charging station by collecting the total daily energy generation data in the raining season and winter. The data suggests that the designed off-grid solar power charging station for electric motorcycle is able to supply sufficient energy for daily charging requirements.
Developing a Hybrid Solar/Wind Powered Drip Irrigation System for Dragon Fruit Yield
NASA Astrophysics Data System (ADS)
Widiastuti, I.; Wijayanto, D. S.
2017-03-01
Irrigation operations take a large amount of water and energy which impact to total costs of crop production. Development of an efficient irrigation supplying precise amount of water and conserving the use of energy can have benefits not only by reducing the operating costs but also by enhancing the farmland productivity. This article presents an irrigation method that promotes sustainable use of water and energy appropriate for a developing tropical country. It proposes a drip irrigation system supported by a combined solar-wind electric power generation system for efficient use of water in dragon fruit cultivation. The electric power generated is used to drive a water pump filling a storage tank for irrigating a 3000 m2 dragon fruit yield in Nguntoronadi, Wonogiri, Indonesia. In designing the irrigation system, the plant’s water requirement was identified based on the value of reference evapotranspiration of the area. A cost/benefit analysis was performed to evaluate the economic feasibility of the proposed scheme. The installation of this solar and wind drip irrigation helps provide sufficient quantity of water to each plant using renewable energy sources which reduce dependence on fossil fuel.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mac Dougall, James
2016-02-05
Many U.S. manufacturing facilities generate unrecovered, low-grade waste heat, and also generate or are located near organic-content waste effluents. Bioelectrochemical systems, such as microbial fuel cells and microbial electrolysis cells, provide a means to convert organic-content effluents into electric power and useful chemical products. A novel biochemical electrical system for industrial manufacturing processes uniquely integrates both waste heat recovery and waste effluent conversion, thereby significantly reducing manufacturing energy requirements. This project will enable the further development of this technology so that it can be applied across a wide variety of US manufacturing segments, including the chemical, food, pharmaceutical, refinery, andmore » pulp and paper industries. It is conservatively estimated that adoption of this technology could provide nearly 40 TBtu/yr of energy, or more than 1% of the U.S. total industrial electricity use, while reducing CO 2 emissions by more than 6 million tons per year. Commercialization of this technology will make a significant contribution to DOE’s Industrial Technology Program goals for doubling energy efficiency and providing a more robust and competitive domestic manufacturing base.« less
Electric power quarterly, January-March 1984
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
1984-07-01
The Electric Power Quarterly (EPQ) provides electric utilities' plant-level information about the cost, quantity, and quality of fossil fuel receipts, net generation, fuel consumption, and fuel stocks. The EPQ contains monthly data and quarterly totals for the reporting quarter. These data are published to provide meaningful, timely, objective, and accurate energy information for a wide audience including Congress, Federal and State agencies, industry, and the general public.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Uryupin, S A; Frolov, A A
We have developed a theory of generation of low-frequency radiation and surface waves under the pondermotive action of a femtosecond laser pulse irradiating a conductor along the normal and focused by a cylindrical lens. It is shown that for the chosen focusing method and specified values of laser pulse duration and flux density it is possible to significantly increase the total energy of both surface waves and low-frequency radiation. (terahertz radiation)
Electron-Impact Total Ionization Cross Sections of CH and C2H2
Kim, Yong-Ki; Ali, M. Asgar; Rudd, M. Eugene
1997-01-01
Electron-impact total ionization cross sections for the CH radical and C2H2 (acetylene) have been calculated using the Binary-Encounter-Bethe (BEB) model. The BEB model combines the Mott cross section and the asymptotic form of the Bethe theory, and has been shown to generate reliable ionization cross sections for a large variety of molecules. The BEB cross sections for CH and C2H2 are in good agreement with the available experimental data from ionization thresholds to hundreds of eV in incident energies. PMID:27805116
NASA Astrophysics Data System (ADS)
Wang, Jianzong; Chen, Yanjun; Hua, Rui; Wang, Peng; Fu, Jia
2012-02-01
Photovoltaic is a method of generating electrical power by converting solar radiation into direct current electricity using semiconductors that exhibit the photovoltaic effect. Photovoltaic power generation employs solar panels composed of a number of solar cells containing a photovoltaic material. Due to the growing demand for renewable energy sources, the manufacturing of solar cells and photovoltaic arrays has advanced considerably in recent years. Solar photovoltaics are growing rapidly, albeit from a small base, to a total global capacity of 40,000 MW at the end of 2010. More than 100 countries use solar photovoltaics. Driven by advances in technology and increases in manufacturing scale and sophistication, the cost of photovoltaic has declined steadily since the first solar cells were manufactured. Net metering and financial incentives, such as preferential feed-in tariffs for solar-generated electricity; have supported solar photovoltaics installations in many countries. However, the power that generated by solar photovoltaics is affected by the weather and other natural factors dramatically. To predict the photovoltaic energy accurately is of importance for the entire power intelligent dispatch in order to reduce the energy dissipation and maintain the security of power grid. In this paper, we have proposed a big data system--the Solar Photovoltaic Power Forecasting System, called SPPFS to calculate and predict the power according the real-time conditions. In this system, we utilized the distributed mixed database to speed up the rate of collecting, storing and analysis the meteorological data. In order to improve the accuracy of power prediction, the given neural network algorithm has been imported into SPPFS.By adopting abundant experiments, we shows that the framework can provide higher forecast accuracy-error rate less than 15% and obtain low latency of computing by deploying the mixed distributed database architecture for solar-generated electricity.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Komiyama, Ryoichi; Marnay, Chris; Stadler, Michael
In this analysis, the authors projected Japan's energy demand/supply and energy-related CO{sub 2} emissions to 2050. Their analysis of various scenarios indicated that Japan's CO{sub 2} emissions in 2050 could be potentially reduced by 26-58% from the current level (FY 2005). These results suggest that Japan could set a CO{sub 2} emission reduction target for 2050 at between 30% and 60%. In order to reduce CO{sub 2} emissions by 60% in 2050 from the present level, Japan will have to strongly promote energy conservation at the same pace as an annual rate of 1.9% after the oil crises (to cutmore » primary energy demand per GDP (TPES/GDP) in 2050 by 60% from 2005) and expand the share of non-fossil energy sources in total primary energy supply in 2050 to 50% (to reduce CO{sub 2} emissions per primary energy demand (CO{sub 2}/TPES) in 2050 by 40% from 2005). Concerning power generation mix in 2050, nuclear power will account for 60%, solar and other renewable energy sources for 20%, hydro power for 10% and fossil-fired generation for 10%, indicating substantial shift away from fossil fuel in electric power supply. Among the mitigation measures in the case of reducing CO{sub 2} emissions by 60% in 2050, energy conservation will make the greatest contribution to the emission reduction, being followed by solar power, nuclear power and other renewable energy sources. In order to realize this massive CO{sub 2} abatement, however, Japan will have to overcome technological and economic challenges including the large-scale deployment of nuclear power and renewable technologies.« less
[Efficiency of oxidant gas generator cells powered by electric or solar energy].
Brust Carmona, H; Benitez, A; Zarco, J; Sánchez, E; Mascher, I
1998-02-01
Diseases caused by microbial contaminants in drinking water continue to be a serious problem in countries like Mexico. Chlorination, using chlorine gas or chlorine compounds, is one of the best ways to treat drinking water. However, difficulties in handling chlorine gas and the inefficiency of hypochlorite solution dosing systems--due to sociopolitical, economic, and cultural factors--have reduced the utility of these chlorination procedures, especially in far-flung and inaccessible rural communities. These problems led to the development of appropriate technologies for the disinfection of water by means of the on-site generation of mixed oxidant gases (chlorine and ozone). This system, called MOGGOD, operates through the electrolysis of a common salt solution. Simulated system evaluation using a hydraulic model allowed partial and total costs to be calculated. When powered by electrical energy from the community power grid, the system had an efficiency of 90%, and in 10 hours it was able to generate enough gases to disinfect about 200 m3 of water at a cost of approximately N$8 (US $1.30). When the electrolytic cell was run on energy supplied through a photoelectric cell, the investment costs were higher. A system fed by photovoltaic cells could be justified in isolated communities that lack electricity but have a gravity-fed water distribution system.
Rhenium-188 Production in Hospitals, by W-188/Re-188 Generator, for Easy Use in Radionuclide Therapy
Argyrou, Maria; Valassi, Alexia; Andreou, Maria; Lyra, Maria
2013-01-01
Rhenium-188 (Re-188) is a high energy β-emitting radioisotope obtained from the tungsten-188/rhenium-188 (W-188/Re-188) generator, which has shown utility for a variety of therapeutic applications in nuclear medicine, oncology, and interventional radiology/cardiology. Re-188 decay is accompanied by a 155 keV predominant energy γ-emission, which could be detected by γ-cameras, for imaging, biodistribution, or absorbed radiation dose studies. Its attractive physical properties and its potential low cost associated with a long-lived parent make it an interesting option for clinical use. The setup and daily use of W-188/Re-188 generator in hospital nuclear medicine departments are discussed in detail. The clinical efficacy, for several therapeutic applications, of a variety of Re-188-labeled agents is demonstrated. The high energy of the β-emission of Re-188 is particularly well suited for effective penetration in solid tumours. Its total radiation dose delivered to tissues is comparable to other radionuclides used in therapy. Furthermore, radiation safety and shielding requirements are an important subject of matter. In the case of bone metastases treatment, therapeutic ratios are presented in order to describe the efficacy of Re-188 usage. PMID:23653859
Argyrou, Maria; Valassi, Alexia; Andreou, Maria; Lyra, Maria
2013-01-01
Rhenium-188 (Re-188) is a high energy β-emitting radioisotope obtained from the tungsten-188/rhenium-188 (W-188/Re-188) generator, which has shown utility for a variety of therapeutic applications in nuclear medicine, oncology, and interventional radiology/cardiology. Re-188 decay is accompanied by a 155 keV predominant energy γ-emission, which could be detected by γ-cameras, for imaging, biodistribution, or absorbed radiation dose studies. Its attractive physical properties and its potential low cost associated with a long-lived parent make it an interesting option for clinical use. The setup and daily use of W-188/Re-188 generator in hospital nuclear medicine departments are discussed in detail. The clinical efficacy, for several therapeutic applications, of a variety of Re-188-labeled agents is demonstrated. The high energy of the β-emission of Re-188 is particularly well suited for effective penetration in solid tumours. Its total radiation dose delivered to tissues is comparable to other radionuclides used in therapy. Furthermore, radiation safety and shielding requirements are an important subject of matter. In the case of bone metastases treatment, therapeutic ratios are presented in order to describe the efficacy of Re-188 usage.
Electric Power Quarterly, January-March 1983
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
1983-07-01
The Electric Power Quarterly (EPQ), a new series in the EIA statistical publications, provides electric utilities' plant-level information about the cost, quantity, and quality of fossil fuel receipts, net generation, fuel consumption and fuel stocks. The EPQ contains monthly data and quarterly totals for the reporting quarter. The data presented in this report were collected and published by the EIA to fulfill its responsibilities as specified in the Federal Energy Administration Act of 1974 (P.L. 93-275). This edition of the EPQ contains monthly data for the first quarter of 1983. In this report, data collected on Form EIA-759 regarding electricmore » utilities' net generation, fuel consumption, and fuel stocks are presented for the first time on a plant-by-plant basis. In addition, quantity, cost, and quality of fossil fuel receipts collected on the Federal Energy Regulatory Commission (FERC) Form 423 are presented on a plant-by-plant basis.« less
NASA Astrophysics Data System (ADS)
Averyt, K.; Macknick, J.; Rogers, J.; Madden, N.; Fisher, J.; Meldrum, J.; Newmark, R.
2013-03-01
Water use by the electricity sector represents a significant portion of the United States water budget (41% of total freshwater withdrawals; 3% consumed). Sustainable management of water resources necessitates an accurate accounting of all water demands, including water use for generation of electricity. Since 1985, the Department of Energy (DOE) Energy Information Administration (EIA) has collected self-reported data on water consumption and withdrawals from individual power generators. These data represent the only annual collection of water consumption and withdrawals by the electricity sector. Here, we compile publically available information into a comprehensive database and then calculate water withdrawals and consumptive use for power plants in the US. In effect, we evaluate the quality of water use data reported by EIA for the year 2008. Significant differences between reported and calculated water data are evident, yet no consistent reason for the discrepancies emerges.
NASA Astrophysics Data System (ADS)
Cherdizov, R. K.; Fursov, F. I.; Kokshenev, V. A.; Kurmaev, N. E.; Labetsky, A. Yu; Ratakhin, N. A.; Shishlov, A. V.; Cikhardt, J.; Cikhardtova, B.; Klir, D.; Kravarik, J.; Kubes, P.; Rezac, K.; Dudkin, G. N.; Garapatsky, A. A.; Padalko, V. N.; Varlachev, V. A.
2017-05-01
The Z-pinch experiments with deuterium gas-puff surrounded by an outer plasma shell were carried out on the GIT-12 generator (Tomsk, Russia) at currents of 2 MA. The plasma shell consisting of hydrogen and carbon ions was formed by 48 plasma guns. The deuterium gas-puff was created by a fast electromagnetic valve. This configuration provides an efficient mode of the neutron production in DD reaction, and the neutron yield reaches a value above 1012 neutrons per shot. Neutron diagnostics included scintillation TOF detectors for determination of the neutron energy spectrum, bubble detectors BD-PND, a silver activation detector, and several activation samples for determination of the neutron yield analysed by a Sodium Iodide (NaI) and a high-purity Germanium (HPGe) detectors. Using this neutron diagnostic complex, we measured the total neutron yield and amount of high-energy neutrons.
Transportation Sector Model of the National Energy Modeling System. Volume 1
DOE Office of Scientific and Technical Information (OSTI.GOV)
NONE
1998-01-01
This report documents the objectives, analytical approach and development of the National Energy Modeling System (NEMS) Transportation Model (TRAN). The report catalogues and describes the model assumptions, computational methodology, parameter estimation techniques, model source code, and forecast results generated by the model. The NEMS Transportation Model comprises a series of semi-independent models which address different aspects of the transportation sector. The primary purpose of this model is to provide mid-term forecasts of transportation energy demand by fuel type including, but not limited to, motor gasoline, distillate, jet fuel, and alternative fuels (such as CNG) not commonly associated with transportation. Themore » current NEMS forecast horizon extends to the year 2010 and uses 1990 as the base year. Forecasts are generated through the separate consideration of energy consumption within the various modes of transport, including: private and fleet light-duty vehicles; aircraft; marine, rail, and truck freight; and various modes with minor overall impacts, such as mass transit and recreational boating. This approach is useful in assessing the impacts of policy initiatives, legislative mandates which affect individual modes of travel, and technological developments. The model also provides forecasts of selected intermediate values which are generated in order to determine energy consumption. These elements include estimates of passenger travel demand by automobile, air, or mass transit; estimates of the efficiency with which that demand is met; projections of vehicle stocks and the penetration of new technologies; and estimates of the demand for freight transport which are linked to forecasts of industrial output. Following the estimation of energy demand, TRAN produces forecasts of vehicular emissions of the following pollutants by source: oxides of sulfur, oxides of nitrogen, total carbon, carbon dioxide, carbon monoxide, and volatile organic compounds.« less
Managing risks of market price uncertainty for a microgrid operation
NASA Astrophysics Data System (ADS)
Raghavan, Sriram
After deregulation of electricity in the United States, the day-ahead and real-time markets allow load serving entities and generation companies to bid and purchase/sell energy under the supervision of the independent system operator (ISO). The electricity market prices are inherently uncertain, and can be highly volatile. The main objective of this thesis is to hedge against the risk from the uncertainty of the market prices when purchasing/selling energy from/to the market. The energy manager can also schedule distributed generators (DGs) and storage of the microgrid to meet the demand, in addition to energy transactions from the market. The risk measure used in this work is the variance of the uncertain market purchase/sale cost/revenue, assuming the price following a Gaussian distribution. Using Markowitz optimization, the risk is minimized to find the optimal mix of purchase from the markets. The problem is formulated as a mixed integer quadratic program. The microgrid at Illinois Institute of Technology (IIT) in Chicago, IL was used as a case study. The result of this work reveals the tradeoff faced by the microgrid energy manager between minimizing the risk and minimizing the mean of the total operating cost (TOC) of the microgrid. With this information, the microgrid energy manager can make decisions in the day-ahead and real-time markets according to their risk aversion preference. The assumption of market prices following Gaussian distribution is also verified to be reasonable for the purpose of hedging against their risks. This is done by comparing the result of the proposed formulation with that obtained from the sample market prices randomly generated using the distribution of actual historic market price data.
Liberian energy consumption and sectoral distribution for 1981
DOE Office of Scientific and Technical Information (OSTI.GOV)
Samuels, G.
1985-02-01
This report is one of a series of project papers providing background information for an assessment of energy options for Liberia, West Africa; it summarizes 1981 Liberian energy consumption data collected during 1982. Total Liberian primary energy consumption in 1981 was equivalent to 11,400,000 barrels of crude oil (BCOE) - 64% from wood, 31% from petroleum, and 5% from hydro. About 71% (8,100,000 BCOE) entered the domestic market. The difference represents exports (400,000 BCOE), refining losses (200,000 BCOE), and losses in converting wood to charcoal (2,600,000 BCOE). Of the 8,100,000 BCOE entering the domestic market, 58% was in the formmore » of wood and charcoal, 35% petroleum products, and 7% hydro. Excluding wood and charcoal, electricity generation consumed 59% of the energy entering the domestic market. The three iron ore mining companies accounted for 60% of all electricity production; the Liberia Electricity Corporation for 35%, and private organizations and individuals for 5%. The mining operations (including electricity generation and transportation uses) consumed about 60% of all petroleum products. The transportation sector consumed 30% of all petroleum of which 85% was for road transport, 12% for the railroads owned and operated by the mining companies, and 3% for sea and air transport. Nontransportation energy use in the industrial, commercial, government, and agriculture and forestry sectors is small. Together, these sectors account for less than 10% of the petroleum products consumed. Wood and charcoal were used almost entirely by the residential sector, which also consumed an additional 530,000 BCOE of other fuels. Over 90% of the 530,000 BCOE was for electricity and 290,000 (56%) was from petroleum. Over half of the petroleum (150,000 BCOE) was for generation at the mines for their associated communities. 8 references, 10 tables.« less
A novel microgrid demand-side management system for manufacturing facilities
NASA Astrophysics Data System (ADS)
Harper, Terance J.
Thirty-one percent of annual energy consumption in the United States occurs within the industrial sector, where manufacturing processes account for the largest amount of energy consumption and carbon emissions. For this reason, energy efficiency in manufacturing facilities is increasingly important for reducing operating costs and improving profits. Using microgrids to generate local sustainable power should reduce energy consumption from the main utility grid along with energy costs and carbon emissions. Also, microgrids have the potential to serve as reliable energy generators in international locations where the utility grid is often unstable. For this research, a manufacturing process that had approximately 20 kW of peak demand was matched with a solar photovoltaic array that had a peak output of approximately 3 KW. An innovative Demand-Side Management (DSM) strategy was developed to manage the process loads as part of this smart microgrid system. The DSM algorithm managed the intermittent nature of the microgrid and the instantaneous demand of the manufacturing process. The control algorithm required three input signals; one from the microgrid indicating the availability of renewable energy, another from the manufacturing process indicating energy use as a percent of peak production, and historical data for renewable sources and facility demand. Based on these inputs the algorithm had three modes of operation: normal (business as usual), curtailment (shutting off non-critical loads), and energy storage. The results show that a real-time management of a manufacturing process with a microgrid will reduce electrical consumption and peak demand. The renewable energy system for this research was rated to provide up to 13% of the total manufacturing capacity. With actively managing the process loads with the DSM program alone, electrical consumption from the utility grid was reduced by 17% on average. An additional 24% reduction was accomplished when the microgrid and DSM program was enabled together, resulting in a total reduction of 37%. On average, peak demand was reduced by 6%, but due to the intermittency of the renewable source and the billing structure for peak demand, only a 1% reduction was obtained. During a billing period, it only takes one day when solar irradiance is poor to affect the demand reduction capabilities. To achieve further demand reduction, energy storage should be introduced and integrated.
Barbosa, Larissa de Souza Noel Simas; Bogdanov, Dmitrii; Vainikka, Pasi; Breyer, Christian
2017-01-01
Power systems for South and Central America based on 100% renewable energy (RE) in the year 2030 were calculated for the first time using an hourly resolved energy model. The region was subdivided into 15 sub-regions. Four different scenarios were considered: three according to different high voltage direct current (HVDC) transmission grid development levels (region, country, area-wide) and one integrated scenario that considers water desalination and industrial gas demand supplied by synthetic natural gas via power-to-gas (PtG). RE is not only able to cover 1813 TWh of estimated electricity demand of the area in 2030 but also able to generate the electricity needed to fulfil 3.9 billion m3 of water desalination and 640 TWhLHV of synthetic natural gas demand. Existing hydro dams can be used as virtual batteries for solar and wind electricity storage, diminishing the role of storage technologies. The results for total levelized cost of electricity (LCOE) are decreased from 62 €/MWh for a highly decentralized to 56 €/MWh for a highly centralized grid scenario (currency value of the year 2015). For the integrated scenario, the levelized cost of gas (LCOG) and the levelized cost of water (LCOW) are 95 €/MWhLHV and 0.91 €/m3, respectively. A reduction of 8% in total cost and 5% in electricity generation was achieved when integrating desalination and power-to-gas into the system.
Barbosa, Larissa de Souza Noel Simas; Bogdanov, Dmitrii; Vainikka, Pasi; Breyer, Christian
2017-01-01
Power systems for South and Central America based on 100% renewable energy (RE) in the year 2030 were calculated for the first time using an hourly resolved energy model. The region was subdivided into 15 sub-regions. Four different scenarios were considered: three according to different high voltage direct current (HVDC) transmission grid development levels (region, country, area-wide) and one integrated scenario that considers water desalination and industrial gas demand supplied by synthetic natural gas via power-to-gas (PtG). RE is not only able to cover 1813 TWh of estimated electricity demand of the area in 2030 but also able to generate the electricity needed to fulfil 3.9 billion m3 of water desalination and 640 TWhLHV of synthetic natural gas demand. Existing hydro dams can be used as virtual batteries for solar and wind electricity storage, diminishing the role of storage technologies. The results for total levelized cost of electricity (LCOE) are decreased from 62 €/MWh for a highly decentralized to 56 €/MWh for a highly centralized grid scenario (currency value of the year 2015). For the integrated scenario, the levelized cost of gas (LCOG) and the levelized cost of water (LCOW) are 95 €/MWhLHV and 0.91 €/m3, respectively. A reduction of 8% in total cost and 5% in electricity generation was achieved when integrating desalination and power-to-gas into the system. PMID:28329023
Investigation of applications for high-power, self-critical fissioning uranium plasma reactors
NASA Technical Reports Server (NTRS)
Rodgers, R. J.; Latham, T. S.; Krascella, N. L.
1976-01-01
Analytical studies were conducted to investigate potentially attractive applications for gaseous nuclear cavity reactors fueled by uranium hexafluoride and its decomposition products at temperatures of 2000 to 6000 K and total pressures of a few hundred atmospheres. Approximate operating conditions and performance levels for a class of nuclear reactors in which fission energy removal is accomplished principally by radiant heat transfer from the high temperature gaseous nuclear fuel to surrounding absorbing media were determined. The results show the radiant energy deposited in the absorbing media may be efficiently utilized in energy conversion system applications which include (1) a primary energy source for high thrust, high specific impulse space propulsion, (2) an energy source for highly efficient generation of electricity, and (3) a source of high intensity photon flux for heating working fluid gases for hydrogen production or MHD power extraction.
Influence of eccentric actions on the metabolic cost of resistance exercise
NASA Technical Reports Server (NTRS)
Dudley, Gary A.; Golden, Catherine L.; Tesch, Per A.; Harris, Robert T.; Buchanan, Paul
1991-01-01
The contributions of concentric (con) and eccentric (ecc) muscle actions are evaluated with respect to increasing the metabolic cost of resistance exercise. Male subjects perform leg exercise with either con and ecc actions or only con actions while the net energy cost of the exercise is measured by oxygen consumption data. In both groups, the con actions require 290 J/kg body weight of total work, with an energy cost of 0.003 cal/J. The energy costs for the con/ecc actions of the second group is increased by 14 percent. The metabolic cost of leg exercise is concluded to be primarily generated by the con leg actions, and ecc leg actions increase the resistance with only a slight increase in required energy. The findings are significant for practical applications that emphasize the conservation of energy expenditure during exercise in spacecraft environments.
Bubbler: A Novel Ultra-High Power Density Energy Harvesting Method Based on Reverse Electrowetting
Hsu, Tsung-Hsing; Manakasettharn, Supone; Taylor, J. Ashley; Krupenkin, Tom
2015-01-01
We have proposed and successfully demonstrated a novel approach to direct conversion of mechanical energy into electrical energy using microfluidics. The method combines previously demonstrated reverse electrowetting on dielectric (REWOD) phenomenon with the fast self-oscillating process of bubble growth and collapse. Fast bubble dynamics, used in conjunction with REWOD, provides a possibility to increase the generated power density by over an order of magnitude, as compared to the REWOD alone. This energy conversion approach is particularly well suited for energy harvesting applications and can enable effective coupling to a broad array of mechanical systems including such ubiquitous but difficult to utilize low-frequency energy sources as human and machine motion. The method can be scaled from a single micro cell with 10−6 W output to power cell arrays with a total power output in excess of 10 W. This makes the fabrication of small light-weight energy harvesting devices capable of producing a wide range of power outputs feasible. PMID:26567850
Bubbler: A Novel Ultra-High Power Density Energy Harvesting Method Based on Reverse Electrowetting.
Hsu, Tsung-Hsing; Manakasettharn, Supone; Taylor, J Ashley; Krupenkin, Tom
2015-11-16
We have proposed and successfully demonstrated a novel approach to direct conversion of mechanical energy into electrical energy using microfluidics. The method combines previously demonstrated reverse electrowetting on dielectric (REWOD) phenomenon with the fast self-oscillating process of bubble growth and collapse. Fast bubble dynamics, used in conjunction with REWOD, provides a possibility to increase the generated power density by over an order of magnitude, as compared to the REWOD alone. This energy conversion approach is particularly well suited for energy harvesting applications and can enable effective coupling to a broad array of mechanical systems including such ubiquitous but difficult to utilize low-frequency energy sources as human and machine motion. The method can be scaled from a single micro cell with 10(-6) W output to power cell arrays with a total power output in excess of 10 W. This makes the fabrication of small light-weight energy harvesting devices capable of producing a wide range of power outputs feasible.
Solar-powered unmanned aerial vehicles
DOE Office of Scientific and Technical Information (OSTI.GOV)
Reinhardt, K.C.; Lamp, T.R.; Geis, J.W.
1996-12-31
An analysis was performed to determine the impact of various power system components and mission requirements on the size of solar-powered high altitude long endurance (HALE)-type aircraft. The HALE unmanned aerial vehicle (UAV) has good potential for use in many military and civil applications. The primary power system components considered in this study were photovoltaic (PV) modules for power generation and regenerative fuel cells for energy storage. The impact of relevant component performance on UAV size and capability were considered; including PV module efficiency and mass, power electronics efficiency, and fuel cell specific energy. Mission parameters such as time ofmore » year, flight altitude, flight latitude, and payload mass and power were also varied to determine impact on UAV size. The aircraft analysis method used determines the required aircraft wing aspect ratio, wing area, and total mass based on maximum endurance or minimum required power calculations. The results indicate that the capacity of the energy storage system employed, fuel cells in this analysis, greatly impacts aircraft size, whereas the impact of PV module efficiency and mass is much less important. It was concluded that an energy storage specific energy (total system) of 250--500 Whr/kg is required to enable most useful missions, and that PV cells with efficiencies greater than {approximately} 12% are suitable for use.« less
Impact of the 2017 Solar Eclipse on Smart Grid
NASA Astrophysics Data System (ADS)
Reda, I.; Andreas, A.; Sengupta, M.; Habte, A.
2017-12-01
With the increasing interest in using solar energy as a major contributor to renewable energy utilization, and with the focus on using smart grids to optimize the use of electrical energy based on demand and resources from different locations, arises the need to know the Moon position in the sky with respect to the Sun. When a solar eclipse occurs, the Moon disk might totally or partially shade the Sun disk, which can affect the irradiance level from the sun disk, consequently, a resource on the grid is affected. The Moon position can then provide the smart grid users with information about potential total or partial solar eclipse at different locations in the grid, so that other resources on the grid can be directed where this might be needed when such phenomena occurs. At least five solar eclipses occur yearly at different locations on earth, they can last three hours or more depending on the location, which can have devastating effects on the smart grid users. On August 21, 2017 a partial solar eclipse will occur at the National Renewable Energy Laboratory in Golden, Colorado, USA. The solar irradiance will be measured during the eclipse and compared to the data generated by a model for validation.
Solar Energy Systems for Lunar Oxygen Generation
NASA Technical Reports Server (NTRS)
Colozza, Anthony J.; Heller, Richard S.; Wong, Wayne A.; Hepp, Aloysius F.
2010-01-01
An evaluation of several solar concentrator-based systems for producing oxygen from lunar regolith was performed. The systems utilize a solar concentrator mirror to provide thermal energy for the oxygen production process. Thermal energy to power a Stirling heat engine and photovoltaics are compared for the production of electricity. The electricity produced is utilized to operate the equipment needed in the oxygen production process. The initial oxygen production method utilized in the analysis is hydrogen reduction of ilmenite. Utilizing this method of oxygen production a baseline system design was produced. This baseline system had an oxygen production rate of 0.6 kg/hr with a concentrator mirror size of 5 m. Variations were performed on the baseline design to show how changes in the system size and process (rate) affected the oxygen production rate. An evaluation of the power requirements for a carbothermal lunar regolith reduction reactor has also been conducted. The reactor had a total power requirement between 8,320 to 9,961 W when producing 1000 kg/year of oxygen. The solar concentrator used to provide the thermal power (over 82 percent of the total energy requirement) would have a diameter of less than 4 m.
Electricity generation from food wastes and microbial community structure in microbial fuel cells.
Jia, Jianna; Tang, Yu; Liu, Bingfeng; Wu, Di; Ren, Nanqi; Xing, Defeng
2013-09-01
Microbial fuel cell (MFC) was studied as an alternate and a novel way to dispose food wastes (FWs) in a waste-to-energy form. Different organic loading rate obviously affected the performance of MFCs fed with FWs. The maximum power density of ~18 W/m(3) (~556 mW/m(2)) was obtained at COD of 3200±400 mg/L and the maximum coulombic efficiency (CE) was ~27.0% at COD of 4900±350 mg/L. The maximum removals of COD, total carbohydrate (TC) and total nitrogen (TN) were ~86.4%, ~95.9% and ~16.1%, respectively. Microbial community analysis using 454 pyrosequencing of 16S rRNA gene demonstrated the combination of the dominant genera of the exoelectrogenic Geobacter and fermentative Bacteroides effectively drove highly efficient and reliable MFC systems with functions of organic matters degradation and electricity generation. Copyright © 2013 Elsevier Ltd. All rights reserved.
Status of national CO{sub 2}-mitigation projects and initiatives in the Philippine energy sector
DOE Office of Scientific and Technical Information (OSTI.GOV)
Tupas, C.T.
1996-12-31
The Philippines has a huge energy requirement for the next 30 years in order to achieve its economic growth target. Based on an expected annual GDP growth rate of 6.9 percent, the Philippines total energy requirement is estimated to increase at an average of 6.6 percent annually from 1996 to 2025. Gross energy demand shall increase from 219.0 million barrels of fuel oil equivalent (MMBFOE) in 1996 to 552.4 MMBFOE in 2010 and 1,392.6 MMBFOE by 2025. These energy demand levels shall be driven primarily by the substantial increase in fuel requirements for power generation whose share of total energymore » requirement is 28.3 percent in 1996, 48.0 percent in 2010 and 55.0 percent in 2025. With the expected increase in energy demand, there will necessarily be adverse impacts on the environment. Energy projects and their supporting systems - from fuel extraction and storage to distribution - can and will be major contributors not only to local but also to regional and global environmental pollution and degradation. International experiences and trends in greenhouse gas (GHG) emissions inventory have shown that the energy sector has always been the dominant source of carbon dioxide (CO{sub 2}) - the principal contributor to global climate change. The energy sector`s CO{sub 2} emissions come primarily from fossil fuels combustion. Since energy use is the dominant source of CO{sub 2} emissions, efforts should therefore be concentrated on designing a mitigation strategy in this sector.« less
Greater-than-Class C low-level waste characterization
DOE Office of Scientific and Technical Information (OSTI.GOV)
Piscitella, R.R.
1991-12-31
In 1985, Public Law 99-240 (Low-Level Radioactive Waste Policy Amendments Act of 1985) made the Department of Energy (DOE) responsible for the disposal of greater-than-Class C low-level radioactive waste (GTCC LLW). DOE strategies for storage and disposal of GTCC LLW required characterization of volumes, radionuclide activities, and waste forms. Data from existing literature, disposal records, and original research were used to estimate characteristics, project volumes, and determine radionuclide activities to the years 2035 and 2055. Twenty-year life extensions for 70% of the operating nuclear reactors were assumed to calculate the GTCC LLW available in 2055. The following categories of GTCCmore » LLW were addressed: Nuclear Utilities Waste; Potential Sealed Sources GTCC LLW; DOE-Held Potential GTCC LLW; and Other Generator Waste. It was determined that the largest volume of these wastes, approximately 57%, is generated by nuclear utilities. The Other Generator Waste category contributes approximately 10% of the total GTCC LLW volume projected to the year 2035. DOE-Held Potential GTCC LLW accounts for nearly 33% of all waste projected to the year 2035. Potential Sealed Sources GTCC LLW is less than 0.2% of the total projected volume. The base case total projected volume of GTCC LLW for all categories was 3,250 cubic meters. This was substantially less than previous estimates.« less
Kim, Young-Chan; Hong, Won-Hwa; Zhang, Yuan-Long; Son, Byeung-Hun; Seo, Youn-Kyu; Choi, Jun-Ho
2016-01-01
When asbestos containing materials (ACM) must be removed from the building before demolition, additional greenhouse gas (GHG) emissions are generated. However, precedent studies have not considered the removal of ACM from the building. The present study aimed to develop a model for estimating GHG emissions created by the ACM removal processes, specifically the removal of asbestos cement slates (ACS). The second objective was to use the new model to predict the total GHG emission produced by ACM removal in the entire country of Korea. First, an input-equipment inventory was established for each step of the ACS removal process. Second, an energy consumption database for each equipment type was established. Third, the total GHG emission contributed by each step of the process was calculated. The GHG emissions generated from the 1,142,688 ACS-containing buildings in Korea was estimated to total 23,778 tonCO2eq to 132,141 tonCO2eq. This study was meaningful in that the emissions generated by ACS removal have not been studied before. Furthermore, the study deals with additional problems that can be triggered by the presence of asbestos in building materials. The method provided in this study is expected to contribute greatly to the calculation of GHG emissions caused by ACM worldwide. PMID:27626433
NASA Astrophysics Data System (ADS)
Liu, Zhaosen; Ian, Hou
2016-04-01
We employed a quantum simulation approach to investigate the magnetic properties of monolayer square nanodisks with Dzyaloshinsky-Moriya (DM) interaction. The computational program converged very quickly, and generated chiral spin structures on the disk planes with good symmetry. When the DM interaction is sufficiently strong, multi-domain structures appears, their sizes or average distance between each pair of domains can be approximately described by a modified grid theory. We further found that the external magnetic field and uniaxial magnetic anisotropy both normal to the disk plane lead to reductions of the total free energy and total energy of the nanosystems, thus are able to stabilize and/or induce the vortical structures, however, the chirality of the vortex is still determined by the sign of the DM interaction parameter. Moreover, the geometric shape of the nanodisk affects the spin configuration on the disk plane as well.
Diagnostics of ion beam generated from a Mather type plasma focus device
NASA Astrophysics Data System (ADS)
Lim, L. K.; Ngoi, S. K.; Wong, C. S.; Yap, S. L.
2014-03-01
Diagnostics of ion beam emission from a 3 kJ Mather-type plasma focus device have been performed for deuterium discharge at low pressure regime. Deuterium plasma focus was found to be optimum at pressure of 0.2 mbar. The energy spectrum and total number of ions per shot from the pulsed ion beam are determined by using biased ion collectors, Faraday cup, and solid state nuclear track detector CR-39. Average energy of the ion beam obtained is about 60 keV. Total number of the ions has been determined to be in the order of 1011 per shot. Solid state nuclear track detectors (SSNTD) CR39 are employed to measure the particles at all angular direction from end on (0°) to side on (90°). Particle tracks are registered by SSNTD at 30° to 90°, except the one at the end-on 0°.
NASA Astrophysics Data System (ADS)
Myatt, J. F.; Shaw, J. G.; Solodov, A. A.; Maximov, A. V.; Short, R. W.; Seka, W.; Follett, R. K.; Edgell, D. H.; Froula, D. H.; Goncharov, V. N.
2015-11-01
Hot-electron preheat, caused by laser-plasma instabilities, can impair the performance of inertial confinement fusion implosions. It is therefore imperative to understand processes that can generate hot electrons and to design mitigation strategies should preheat be found to be excessive at the ignition scale (laser-plasma interactions do not follow hydrodynamic scaling). For this purpose, a new 3-D model [laser-plasma simulation environment (LPSE)] has been constructed that computes hot-electron generation in direct-drive plasmas based on the assumption that two-plasmon decay is the dominant, hot-electron-producing instability. It uses an established model of TPD-driven turbulence together with a new GPU based hybrid particle method of hot-electron production. The time-dependent hot-electron power, total energy, and energy spectrum are computed and compared with data from recent OMEGA implosion experiments that have sought to mitigate TPD by the use of multilayered (mid- Z) ablators. This material is based upon work supported by the Department of Energy National Nuclear Security Administration under Award Number DE-NA0001944.
Pirbhulal, Sandeep; Zhang, Heye; Mukhopadhyay, Subhas Chandra; Li, Chunyue; Wang, Yumei; Li, Guanglin; Wu, Wanqing; Zhang, Yuan-Ting
2015-01-01
Body Sensor Network (BSN) is a network of several associated sensor nodes on, inside or around the human body to monitor vital signals, such as, Electroencephalogram (EEG), Photoplethysmography (PPG), Electrocardiogram (ECG), etc. Each sensor node in BSN delivers major information; therefore, it is very significant to provide data confidentiality and security. All existing approaches to secure BSN are based on complex cryptographic key generation procedures, which not only demands high resource utilization and computation time, but also consumes large amount of energy, power and memory during data transmission. However, it is indispensable to put forward energy efficient and computationally less complex authentication technique for BSN. In this paper, a novel biometric-based algorithm is proposed, which utilizes Heart Rate Variability (HRV) for simple key generation process to secure BSN. Our proposed algorithm is compared with three data authentication techniques, namely Physiological Signal based Key Agreement (PSKA), Data Encryption Standard (DES) and Rivest Shamir Adleman (RSA). Simulation is performed in Matlab and results suggest that proposed algorithm is quite efficient in terms of transmission time utilization, average remaining energy and total power consumption. PMID:26131666
Pirbhulal, Sandeep; Zhang, Heye; Mukhopadhyay, Subhas Chandra; Li, Chunyue; Wang, Yumei; Li, Guanglin; Wu, Wanqing; Zhang, Yuan-Ting
2015-06-26
Body Sensor Network (BSN) is a network of several associated sensor nodes on, inside or around the human body to monitor vital signals, such as, Electroencephalogram (EEG), Photoplethysmography (PPG), Electrocardiogram (ECG), etc. Each sensor node in BSN delivers major information; therefore, it is very significant to provide data confidentiality and security. All existing approaches to secure BSN are based on complex cryptographic key generation procedures, which not only demands high resource utilization and computation time, but also consumes large amount of energy, power and memory during data transmission. However, it is indispensable to put forward energy efficient and computationally less complex authentication technique for BSN. In this paper, a novel biometric-based algorithm is proposed, which utilizes Heart Rate Variability (HRV) for simple key generation process to secure BSN. Our proposed algorithm is compared with three data authentication techniques, namely Physiological Signal based Key Agreement (PSKA), Data Encryption Standard (DES) and Rivest Shamir Adleman (RSA). Simulation is performed in Matlab and results suggest that proposed algorithm is quite efficient in terms of transmission time utilization, average remaining energy and total power consumption.
Yambe, T; Hashimoto, H; Kobayashi, S; Sonobe, T; Naganuma, S; Nanka, S S; Matsuki, H; Yoshizawa, M; Tabayashi, K; Takayasu, H; Takeda, H; Nitta, S
1997-01-01
We have developed a vibrating flow pump (VFP) that can generate oscillated blood flow with a relatively high frequency (10-50 Hz) for a totally implantable ventricular assist system (VAS). To evaluate the newly developed VAS, left heart bypasses, using the VFP, were performed in chronic animal experiments. Hemodynamic parameters were recorded in a data recorder in healthy adult goats during an awake condition and analyzed in a personal computer system through an alternating-direct current converter. Basic performance of the total system with a transcutaneous energy transmission system were satisfactory. During left ventricular assistance with the VFP, Mayer wave fluctuations of hemodynamics were decreased in the power spectrum, the fractal dimensions of the hemodynamics were significantly decreased, and peripheral vascular resistance was significantly decreased. These results suggest that cardiovascular regulatory nonlinear dynamics, which mediate the hemodynamics, may be affected by left ventricular bypass with oscillated flow. The decreased power of the Mayer wave in the spectrum caused the limit cycle attractor of the hemodynamics and decreased peripheral resistance. These results suggest that this newly developed VAS is useful for the totally implantable system with unique characteristics that can control hemodynamic properties.
Localized microwave pulsed plasmas for ignition and flame front enhancement
NASA Astrophysics Data System (ADS)
Michael, James Bennett
Modern combustor technologies require the ability to match operational parameters to rapidly changing demands. Challenges include variable power output requirements, variations in air and fuel streams, the requirement for rapid and well-controlled ignition, and the need for reliability at low fuel mixture fractions. Work on subcritical microwave coupling to flames and to weakly ionized laser-generated plasmas has been undertaken to investigate the potential for pulsed microwaves to allow rapid combustion control, volumetric ignition, and leaner combustion. Two strategies are investigated. First, subcritical microwaves are coupled to femtosecond laser-generated ionization to ignite methane/air mixtures in a quasi-volumetric fashion. Total energy levels are comparable to the total minimum ignition energies for laser and spark discharges, but the combined strategy allows a 90 percent reduction in the required laser energy. In addition, well-defined multi-dimensional ignition patterns are designated with multiple laser passes. Second, microwave pulse coupling to laminar flame fronts is achieved through interaction with chemiionization-produced electrons in the reaction zone. This energy deposition remains well-localized for a single microwave pulse, resulting in rapid temperature rises of greater than 200 K and maintaining flame propagation in extremely lean methane/air mixtures. The lean flammability limit in methane/air mixtures with microwave coupling has been decreased from an equivalence ratio 0.6 to 0.3. Additionally, a diagnostic technique for laser tagging of nitrogen for velocity measurements is presented. The femtosecond laser electronic excitation tagging (FLEET) technique utilizes a 120 fs laser to dissociate nitrogen along a laser line. The relatively long-lived emission from recombining nitrogen atoms is imaged with a delayed and fast-gated camera to measure instantaneous velocities. The emission strength and lifetime in air and pure nitrogen allow instantaneous velocity measurements. FLEET is shown to perform in high temperature and reactive mixtures.
Energy alternative for industry: the high-temperature gas-cooled reactor steamer
DOE Office of Scientific and Technical Information (OSTI.GOV)
McMain, A.T. Jr.; Blok, F.J.
1978-04-01
Large industrial complexes are faced with new requirements that will lead to a transition from such fluid fuels as natural gas and oil to such solid fuels as coal and uranium for supply of industrial energy. Power plants using these latter fuels will be of moderate size (800 to 1200 MW(thermal)) and will generally have the capability of co-generating electric power and process steam. A study has been made regarding use of the 840-MW(thermal) Fort St. Vrain high-temperature gas-cooled reactor (HTGR) design for industrial applications. The initial conceptual design (referred to as the HTGR Steamer) is substantially simplified relative tomore » Fort St. Vrain in that outlet helium and steam temperatures are lower and the reheat section is deleted from the steam generators. The Steamer has four independent steam generating loops producing a total of 277 kg/s (2.2 x 10/sup 6/ lb/h) of prime steam at 4.5 MPa/672 K (650 psia/750/sup 0/F). The unit co-generates 46 MW(electric) and provides process steam at 8.31 MPa/762 K(1200 psia/912/sup 0/F). The basic configuration and much of the equipment are retained from the Fort St. Vrain design. The system has inherent safety features important for industrial applications. These and other features indicate that the HTGR Steamer is an industrial energy option deserving additional evaluation. Subsequent work will focus on parallel design optimization and application studies.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Shehabi, Arman; Ganeshalingam, Mohan; DeMates, Lauren
Laboratories are estimated to be 3-5 times more energy intensive than typical office buildings and offer significant opportunities for energy use reductions. Although energy intensity varies widely, laboratories are generally energy intensive due to ventilation requirements, the research instruments used, and other health and safety concerns. Because the requirements of laboratory facilities differ so dramatically from those of other buildings, a clear need exists for an initiative exclusively targeting these facilities. The building stock of laboratories in the United States span different economic sectors, include governmental and academic institution, and are often defined differently by different groups. Information on laboratorymore » buildings is often limited to a small subsection of the total building stock making aggregate estimates of the total U.S. laboratories and their energy use challenging. Previous estimates of U.S. laboratory space vary widely owing to differences in how laboratories are defined and categorized. A 2006 report on fume hoods provided an estimate of 150,000 laboratories populating the U.S. based in part on interviews of industry experts, however, a 2009 analysis of the 2003 Commercial Buildings Energy Consumption Survey (CBECS) generated an estimate of only 9,000 laboratory buildings. This report draws on multiple data sources that have been evaluated to construct an understanding of U.S. laboratories across different sizes and markets segments. This 2016 analysis is an update to draft reports released in October and December 2016.« less
Ahn, Hyo-Sung; Kim, Byeong-Yeon; Lim, Young-Hun; Lee, Byung-Hun; Oh, Kwang-Kyo
2018-03-01
This paper proposes three coordination laws for optimal energy generation and distribution in energy network, which is composed of physical flow layer and cyber communication layer. The physical energy flows through the physical layer; but all the energies are coordinated to generate and flow by distributed coordination algorithms on the basis of communication information. First, distributed energy generation and energy distribution laws are proposed in a decoupled manner without considering the interactive characteristics between the energy generation and energy distribution. Second, a joint coordination law to treat the energy generation and energy distribution in a coupled manner taking account of the interactive characteristics is designed. Third, to handle over- or less-energy generation cases, an energy distribution law for networks with batteries is designed. The coordination laws proposed in this paper are fully distributed in the sense that they are decided optimally only using relative information among neighboring nodes. Through numerical simulations, the validity of the proposed distributed coordination laws is illustrated.
Dissociation cross section for high energy O2-O2 collisions
NASA Astrophysics Data System (ADS)
Mankodi, T. K.; Bhandarkar, U. V.; Puranik, B. P.
2018-04-01
Collision-induced dissociation cross section database for high energy O2-O2 collisions (up to 30 eV) is generated and published using the quasiclassical trajectory method on the singlet, triplet, and quintet spin ground state O4 potential energy surfaces. At equilibrium conditions, these cross sections predict reaction rate coefficients that match those obtained experimentally. The main advantage of the cross section database based on ab initio computations is in the study of complex flows with high degree of non-equilibrium. Direct simulation Monte Carlo simulations using the reactive cross section databases are carried out for high enthalpy hypersonic oxygen flow over a cylinder at rarefied ambient conditions. A comparative study with the phenomenological total collision energy chemical model is also undertaken to point out the difference and advantage of the reported ab initio reaction model.
NASA Astrophysics Data System (ADS)
Wang, Yiping; Tang, Yulin; Deng, Yadong; Su, Chuqi
2018-06-01
Energy conservation and environmental protection have typically been a concern of research. Researchers have confirmed that in automotive engines, just 12-25% of the fuel energy converts into effective work and 30-40% gets wasted in the form of exhaust. Saidur et al. (Energy Policy 37:3650, 2009) and Hasanuzzaman et al. (Energy 36:233, 2011). It will be significant to enhance fuel availability and decrease environmental pollution if the waste heat in the exhaust could be recovered. Thermoelectric generators (TEGs), which can translate heat into electricity, have become a topic of interest for vehicle exhaust waste heat recovery. In conventional automotive TEGs, the thermoelectric modules (TEMs) are arranged between the exhaust tank and the coolant tank. The TEMs do not contact the hot exhaust and coolant, which leads to low heat transfer efficiency. Moreover, to provide enough packing force to keep good contact with the exhaust tank and the coolant tank, the framework required is so robust that the TEGs become too heavy. Therefore, in current study, an automotive TEG was designed which included one exhaust channel, one coolant channel and several TEMs. In the TEG, the TEMs which contacted the exhaust and coolant directly were inserted into the walls of each coolant channel. To evaluate the performance of the automotive TEG, the flow field and temperature field were computed by computational fluid dynamics (CFD). Based on the temperature distribution obtained by CFD and the performance parameters of the modules, the total power generation was obtained by some proved empirical formulas. Compared with conventional automotive TEGs, the power generation per unit volume exhaust was boosted.
Feasibility Evaluation of an On-site Generator Network by the Cooperative Game Theory
NASA Astrophysics Data System (ADS)
Komiyama, Ryoichi; Hayashi, Taketo; Fujii, Yasumasa; Yamaji, Kenji
On-site generator, such as CGS (cogeneration system), is allegedly considered to be an effective end-use energy system in order to accomplish primary energy conservation, CO2 emission mitigation and system cost reduction, which characteristics eventually improve the whole performance of an existing energy system for the future. Considering the drawback of installing an end-use CGS into the customer with small or middle scale floor space, however, it is difficult to achieve those distinctive features because the thermal-electricity ratio of CGS does not always be in agreement with that of customer energy demand. In order to overcome that matching deficiency, it is hence better to organize an on-site generator network based on mutual electricity and heating transmission. But focusing on some cogenerators underlying their behaviors on maximizing their own profits, this on-site network, which situation corresponds to a grand coalition, is not necessarily established because of each cogenerator’s motivation to form a partial coalition and acquire its own profit as much as possible. In this paper, we attempt to analyze the optimal operation of an on-site generator network and identify by applying the nucleolus of the cooperative game theory the optimal benefit allocation strategy in order for the cogenerators to construct the network. Regarding the installation site of this network, the center of Tokyo area is assumed, which locational information includes floor space and so forth through a GIS (geographic information system) database. The results from the nucleolus suggest that all districts should impartially obtain the benefit from organizing network for the purpose of jointly attaining the system total cost reduction.
NASA Astrophysics Data System (ADS)
Wang, Yiping; Tang, Yulin; Deng, Yadong; Su, Chuqi
2017-12-01
Energy conservation and environmental protection have typically been a concern of research. Researchers have confirmed that in automotive engines, just 12-25% of the fuel energy converts into effective work and 30-40% gets wasted in the form of exhaust. Saidur et al. (Energy Policy 37:3650, 2009) and Hasanuzzaman et al. (Energy 36:233, 2011). It will be significant to enhance fuel availability and decrease environmental pollution if the waste heat in the exhaust could be recovered. Thermoelectric generators (TEGs), which can translate heat into electricity, have become a topic of interest for vehicle exhaust waste heat recovery. In conventional automotive TEGs, the thermoelectric modules (TEMs) are arranged between the exhaust tank and the coolant tank. The TEMs do not contact the hot exhaust and coolant, which leads to low heat transfer efficiency. Moreover, to provide enough packing force to keep good contact with the exhaust tank and the coolant tank, the framework required is so robust that the TEGs become too heavy. Therefore, in current study, an automotive TEG was designed which included one exhaust channel, one coolant channel and several TEMs. In the TEG, the TEMs which contacted the exhaust and coolant directly were inserted into the walls of each coolant channel. To evaluate the performance of the automotive TEG, the flow field and temperature field were computed by computational fluid dynamics (CFD). Based on the temperature distribution obtained by CFD and the performance parameters of the modules, the total power generation was obtained by some proved empirical formulas. Compared with conventional automotive TEGs, the power generation per unit volume exhaust was boosted.
NASA Astrophysics Data System (ADS)
Anghileri, Daniela; Botter, Martina; Castelletti, Andrea; Burlando, Paolo
2016-04-01
Alpine hydropower systems are experiencing dramatic changes both from the point of view of hydrological conditions, e.g., water availability and frequency of extremes events, and of energy market conditions, e.g., partial or total liberalization of the market and increasing share of renewable power sources. Scientific literature has, so far, mostly focused on the analysis of climate change impacts and associated uncertainty on hydropower operation, underlooking the consequences that socio-economic changes, e.g., energy demand and/or price changes, can have on hydropower productivity and profitability. In this work, we analyse how hydropower reservoir operation is affected by changes in both water availability and energy price. We consider stochastically downscaled climate change scenarios of precipitation and temperature to simulate reservoir inflows using a physically explicit hydrological model. We consider different scenarios of energy demand and generation mix to simulate energy prices using an electricity market model, which includes different generation sources, demand sinks, and features of the transmission lines. We then use Multi-Objective optimization techniques to design the operation of hydropower reservoirs for different purposes, e.g. maximization of revenue and/or energy production. The objective of the work is to assess how the tradeoffs between the multiple operating objectives evolve under different co-varying climate change and socio-economic scenarios and to assess the adaptive capacity of the system. The modeling framework is tested on the real-world case study of the Mattmark reservoir in Switzerland.
NASA Astrophysics Data System (ADS)
Yazdani, R.; Augenstein, D.; Kieffer, J.; Cohen, K.
2003-12-01
The Department of Public Works of Yolo County, California, USA has been testing an advanced approach to landfill bioreactors, controlled (or "enhanced") landfilling, at its Yolo County Central Landfill site near Davis, CA, since 1994. Overall objectives have been the management of waste landfilling for: (1) rapid completion of total gas generation; (2) maximum, high-efficiency gas capture; (3) waste volume reduction; and (4) maximum greenhouse gas and carbon sequestration benefits. Methane generation is controlled and enhanced through carefully managed moisture additions, and by taking advantage of landfill temperature elevation. The generated landfill methane, an important greenhouse gas, is recovered with high efficiency through extraction from a porous recovery layer beneath a surface geomembrane cover. Instrumentation included a total of 56 moisture and 15 temperature sensors in the two cells, gas flow monitoring by positive displacement gas meters, and accurate quantification of liquid inputs and outputs. Gas composition, waste volume reduction, base hydrostatic head, and a range of environmental compliance parameters has been monitored since 1995. Partitioning gas tracer tests using the injection of two gases at dilute concentrations in the landfill have also been initiated to compute the fraction of pore space occupied by water between the points of tracer injection and tracer measurement. There has been rapid waste volume reduction in the enhanced cell that corresponds to the solids' reduction to gas. Monitoring is planned for the next several years, until stabilization parameters are determined complete. Encouraging performance is indicated by: (1) sensor data; (2) gas generation results; (3) data from landfill cores; and (4) decomposition-related indicators including rapid volume reduction. When data are synthesized, project results have attractive implications for new approaches to landfill management. Over seven-years, methane recoveries have averaged over fivefold the "typical" values for comparable landfill waste. In terms of "greenhouse benefit," fractional VOC and methane energy recovery are estimated to exceed 90%, with corresponding methane and VOC emission reductions. Analyses done for the greenhouse gas mitigation program of the U.S. Department of Energy National Energy Technology Laboratory indicate favorable economics justified on landfill life extension, as well as environmental benefits. The "controlled landfill" project findings suggest potential for low-cost mitigation of waste greenhouse methane emissions, maximum landfill carbon sequestration, and maximization of beneficial energy capture from landfills. Details and results obtained since 1994 will be presented.
Hybrid Energy: Combining Nuclear and Other Energy Sources
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kim, Jong Suk; Garcia, Humberto E.
2015-02-01
The leading cause of global climate change is generally accepted to be growing emissions of greenhouse gas (GHG) as a result of increased use of fossil fuels [1]. Among various sources of GHG, the global electricity supply sector generates the largest share of GHG emissions (37.5% of total CO2 emissions) [2]. Since the current electricity production heavily relies on fossil fuels, it is envisioned that bolstering generation technologies based on non-emitting energy sources, i.e., nuclear and/or renewables could reduce future GHG emissions. Integrated nuclear-renewable hybrid energy systems HES) are very-low-emitting options, but they are capital-intensive technologies that should operate atmore » full capacities to maximize profits. Hence, electricity generators often pay the grid to take electricity when demand is low, resulting in negative profits for many hours per year. Instead of wasting an excess generation capacity at negative profit during off-peak hours when electricity prices are low, nuclear-renewable HES could result in positive profits by storing and/or utilizing surplus thermal and/or electrical energy to produce useful storable products to meet industrial and transportation demands. Consequently, it is necessary (1) to identify key integrated system options based on specific regions and (2) to propose optimal operating strategy to economically produce products on demand. In prioritizing region-specific HES options, available resources, markets, existing infrastructures, and etc. need to be researched to identify attractive system options. For example, the scarcity of water (market) and the availability of abundant solar radiation make solar energy (resource) a suitable option to mitigate the water deficit the Central-Southern region of the U.S. Thus, a solar energy-driven desalination process would be an attractive option to be integrated into a nuclear power plant to support the production of fresh water in this region. In this work, we introduce a particular HES option proposed for a specific U.S. region and briefly describe our modeling assumptions and procedure utilized for its analysis. Preliminary simulation results are also included addressing several technical characteristics of the proposed nuclear-renewable HES.« less
NASA Astrophysics Data System (ADS)
Akahori, Takuya; Kato, Yuichi; Nakazawa, Kazuhiro; Ozawa, Takeaki; Gu, Liyi; Takizawa, Motokazu; Fujita, Yutaka; Nakanishi, Hiroyuki; Okabe, Nobuhiro; Makishima, Kazuo
2018-06-01
We report the Australia Telescope Compact Array 16 cm observation of CIZA J1358.9-4750. Recent X-ray studies imply that this galaxy cluster is composed of merging, binary clusters. Using the EW367 configuration, we found no significant diffuse radio emission in and around the cluster. An upper limit of the total radio power at 1.4 GHz is ˜1.1 × 1022 W Hz-1 in 30 square arcminutes, which is a typical size for radio relics. It is known that an empirical relation holds between the total radio power and X-ray luminosity of the host cluster. The upper limit is about one order of magnitude lower than the power expected from the relation. Very young (˜70 Myr) shocks with low Mach numbers (˜1.3), which are often seen at an early stage of merger simulations, are suggested by the previous X-ray observation. The shocks may generate cosmic-ray electrons with a steep energy spectrum, which is consistent with non-detection of bright (>1023 W Hz-1) relic in this 16 cm band observation. Based on the assumption of energy equipartition, the upper limit gives a magnetic field strength of below 0.68f(Dlos/1 Mpc)-1(γmin/200)-1 μG, where f is the cosmic-ray total energy density over the cosmic-ray electron energy density, Dlos is the depth of the shock wave along the sightline, and γmin is the lower cutoff Lorentz factor of the cosmic-ray electron energy spectrum.
NASA Astrophysics Data System (ADS)
Benyo, Theresa Louise
Historically, the National Aeronautics and Space Administration (NASA) has used rocket-powered vehicles as launch vehicles for access to space. A familiar example is the Space Shuttle launch system. These vehicles carry both fuel and oxidizer onboard. If an external oxidizer (such as the Earth's atmosphere) is utilized, the need to carry an onboard oxidizer is eliminated, and future launch vehicles could carry a larger payload into orbit at a fraction of the total fuel expenditure. For this reason, NASA is currently researching the use of air-breathing engines to power the first stage of two-stage-to-orbit hypersonic launch systems. Removing the need to carry an onboard oxidizer leads also to reductions in total vehicle weight at liftoff. This in turn reduces the total mass of propellant required, and thus decreases the cost of carrying a specific payload into orbit or beyond. However, achieving hypersonic flight with air-breathing jet engines has several technical challenges. These challenges, such as the mode transition from supersonic to hypersonic engine operation, are under study in NASA's Fundamental Aeronautics Program. One propulsion concept that is being explored is a magnetohydrodynamic (MHD) energy- bypass generator coupled with an off-the-shelf turbojet/turbofan. It is anticipated that this engine will be capable of operation from takeoff to Mach 7 in a single flowpath without mode transition. The MHD energy bypass consists of an MHD generator placed directly upstream of the engine, and converts a portion of the enthalpy of the inlet flow through the engine into electrical current. This reduction in flow enthalpy corresponds to a reduced Mach number at the turbojet inlet so that the engine stays within its design constraints. Furthermore, the generated electrical current may then be used to power aircraft systems or an MHD accelerator positioned downstream of the turbojet. The MHD accelerator operates in reverse of the MHD generator, re-accelerating the exhaust flow from the engine by converting electrical current back into flow enthalpy to increase thrust. Though there has been considerable research into the use of MHD generators to produce electricity for industrial power plants, interest in the technology for flight-weight aerospace applications has developed only recently. In this research, electromagnetic fields coupled with weakly ionzed gases to slow hypersonic airflow were investigated within the confines of an MHD energy-bypass system with the goal of showing that it is possible for an air-breathing engine to transition from takeoff to Mach 7 without carrying a rocket propulsion system along with it. The MHD energy-bypass system was modeled for use on a supersonic turbojet engine. The model included all components envisioned for an MHD energy-bypass system; two preionizers, an MHD generator, and an MHD accelerator. A thermodynamic cycle analysis of the hypothesized MHD energy-bypass system on an existing supersonic turbojet engine was completed. In addition, a detailed thermodynamic, plasmadynamic, and electromagnetic analysis was combined to offer a single, comprehensive model to describe more fully the proper plasma flows and magnetic fields required for successful operation of the MHD energy bypass system. The unique contribution of this research involved modeling the current density, temperature, velocity, pressure, electric field, Hall parameter, and electrical power throughout an annular MHD generator and an annular MHD accelerator taking into account an external magnetic field within a moving flow field, collisions of electrons with neutral particles in an ionized flow field, and collisions of ions with neutral particles in an ionized flow field (ion slip). In previous research, the ion slip term has not been considered. The MHD energy-bypass system model showed that it is possible to expand the operating range of a supersonic jet engine from a maximum of Mach 3.5 to a maximum of Mach 7. The inclusion of ion slip within the analysis further showed that it is possible to 'drive' this system with maximum magnetic fields of 3 T and with maximum conductivity levels of 11 mhos/m. These operating parameters better the previous findings of 5 T and 10 mhos/m, and reveal that taking into account collisions between ions and neutral particles within a weakly ionized flow provides a more realistic model with added benefits of lower magnetic fields and conductivity levels especially at the higher Mach numbers. (Abstract shortened by UMI.).
Yoon, Young-Man; Kim, Seung-Hwan; Oh, Seung-Yong; Kim, Chang-Hyun
2014-01-01
This study was carried out to assess the material and energy recovery by organic solid wastes generated from a poultry slaughterhouse. In a poultry slaughterhouse involving the slaughtering of 100,000 heads per day, poultry manure & feather from the mooring stage, blood from the bleeding stage, intestine residue from the evisceration stage, and sludge cake from the wastewater treatment plant were discharged at a unit of 0.24, 4.6, 22.8, and 2.2 Mg day(-1), consecutively. The amount of nitrogen obtained from the poultry slaughterhouse was 22.36 kg 1000 head(-1), phosphate and potash were 0.194 kg 1000 head(-1) and 0.459 kg 1000 head(-1), respectively. As regards nitrogen recovery, the bleeding and evisceration stages accounted for 28.0% and 65.8% of the total amount of recovered nitrogen. Energy recovered from the poultry slaughterhouse was 35.4 Nm(3) 1000 head(-1) as CH4. Moreover, evisceration and wastewater treatment stage occupied 88.1% and 7.2% of the total recovered CH4 amount, respectively. Copyright © 2013 Elsevier Ltd. All rights reserved.
Generation of Coherent Structures After Cosmic Inflation
NASA Astrophysics Data System (ADS)
Gleiser, Marcelo
2013-04-01
The transition from inflation to power-law expansion is a rich nonlinear nonequilibrium physical process. For this reason, much is still unknown about this epoch in early universe physics, which has been dubbed the ``new big bang" by many colleagues. Here I describe results from the past few years of research, some of which in collaboration with Noah Graham and Nik Stamatopoulos, where we explored the generation on extended structures at the end of inflation known as oscillons. In particular, in hybrid inflation models we solve the coupled Einstein-Klein-Gordon equations to find that as the field responsible for inflating the universe rolls down to oscillate about its minimum, it triggers the formation of long-lived two-field oscillons, which can contribute up to 20% of the total energy density of the universe. We show that these oscillons emerge for a wide range of parameters consistent with WMAP 7-year data. These objects contain total energy of about 25x10^20 GeV, localized in a region of approximate radius 6x10-26 cm. We argue that these structures could have played a key role during the reheating of the universe, influencing the reheating temperature. We also explore the notion that these objects will appear in most symmetry-breaking phase transitions.
NASA Astrophysics Data System (ADS)
Shashank, R.; Harisha, S. K., Dr; Abhishek, M. C.
2018-02-01
Energy harvesting using ambient energy sources is one of the fast growing trends in the world, research and development in the area of energy harvesting is moving progressively to get maximum power output from the existing resources. The ambient sources of energy available in the nature are solar energy, wind energy, thermal energy, vibrational energy etc. out of these methods energy harvesting by vibrational energy sources gain more importance due to its nature of not getting influenced by any environmental parameters and its free availability at anytime and anywhere. The project mainly deals with validating the values of voltage and electrical power output of experimentally conducted energy harvester, varying the parameters of the energy harvester and analyse the effect of the parameters on the performance of the energy harvester and compare the results. The cantilever beam was designed, analysed and simulated using COMSOL multi-physics software. The energy harvester gives an electrical output voltage of the 2.75 volts at a natural frequency of 37.2 Hz and an electrical power of 29μW. Decreasing the percentage of the piezoelectric material and simultaneously increasing the percentage of polymer material (so that total percentage of proportion remains same) increases the electrical voltage and decreases the natural frequency of the beam linearly upto 3.9V and 28.847 Hz till the percentage proportion of the beam was 24% piezoelectric beam and 76% polymer beam when the percentage proportion increased to 26% and 74% natural frequency goes on decreases further but voltage suddenly drops to 2.8V. The voltage generated by energy harvester increases proportionally and reaches 3.7V until weight of the proof mass reaches 4 grams and further increase in the weight of the proof mass decreases the voltage generated by energy harvester. Thus the investigation conveys that the weight of the proof mass and the length of the cantilever beam should be optimised to obtain maximum output efficiency of energy harvester.
Effective utilization of ozone in plasma-based advanced oxidation process
NASA Astrophysics Data System (ADS)
Takeuchi, Nozomi; Ishibashi, Naoto; Sugiyama, Tsuyoshi; Kim, Hyun-Ha
2018-05-01
Decomposition of acetic acid in water was conducted using multiple plasmas generated within oxygen bubbles. Ballast capacitors were used to control the plasma input power, allowing hydrogen peroxide and ozone to be produced at different rates in each plasma by adjusting the capacitance. By using an ozone absorber connected to the plasma reactor, OH radicals, both generated by the plasmas directly and reproduced from hydrogen peroxide through reactions with ozone, could be effectively utilized for the reduction of total organic carbon (TOC). Under the condition with the highest ozone production rate, higher processing speed and energy efficiency for the TOC reduction were achieved compared with other plasma methods.
A small portable proton exchange membrane fuel cell and hydrogen generator for medical applications.
Adlhart, O J; Rohonyi, P; Modroukas, D; Driller, J
1997-01-01
Small, lightweight power sources for total artificial hearts (TAH), left ventricular assist devices (LVAD), and other medical products are under development. The new power source will provide 2 to 3 times the capacity of conventional batteries. The implications of this new power source are profound. For example, for the Heartmate LVAD, 5 to 8 hours of operation are obtained with 3 lb of lead acid batteries (Personal Communication Mr. Craig Sherman, Thermo Cardiosystems, Inc TCI 11/29/96). With the same weight, as much as 14 hours of operation appear achievable with the proton exchange membrane (PEM) fuel cell power source. Energy densities near 135 watt-hour/L are achievable. These values significantly exceed those of most conventional and advanced primary and secondary batteries. The improvement is mission dependent and even applies for the short deployment cited above. The comparison to batteries becomes even more favorable if the mission length is increased. The higher capacity requires only replacement of lightweight hydride cartridges and logistically available water. Therefore, when one spare 50 L hydride cartridge weighing 115 g is added to the reactant supply the energy density of the total system increases to 230 watt-hour/kg. This new power source is comprised of a hydrogen fueled, air-breathing PEM fuel cell and a miniature hydrogen generator (US Patent No 5,514,353). The fuel cell is of novel construction and differs from conventional bipolar PEM fuel cells by the arrangement of cells on a single sheet of ion-exchange membrane. The construction avoids the weight and volume penalty of conventional bipolar stacks. The hydrogen consumed by the fuel cell is generated load-responsively in the miniature hydrogen generator, by reacting calcium hydride with water, forming in the process hydrogen and lime. The generator is cartridge rechargeable and available in capacities providing up to several hundred watt-hours of electric power.
Density functional theory calculations of the water interactions with ZrO2 nanoparticles Y2O3 doped
NASA Astrophysics Data System (ADS)
Subhoni, Mekhrdod; Kholmurodov, Kholmirzo; Doroshkevich, Aleksandr; Asgerov, Elmar; Yamamoto, Tomoyuki; Lyubchyk, Andrei; Almasan, Valer; Madadzada, Afag
2018-03-01
Development of a new electricity generation techniques is one of the most relevant tasks, especially nowadays under conditions of extreme growth in energy consumption. The exothermic heterogeneous electrochemical energy conversion to the electric energy through interaction of the ZrO2 based nanopowder system with atmospheric moisture is one of the ways of electric energy obtaining. The questions of conversion into the electric form of the energy of water molecules adsorption in 3 mol% Y2O3 doped ZrO2 nanopowder systems were investigated using the density functional theory calculations. The density functional theory calculations has been realized as in the Kohn-Sham formulation, where the exchange-correlation potential is approximated by a functional of the electronic density. The electronic density, total energy and band structure calculations are carried out using the all-electron, full potential, linear augmented plane wave method of the electronic density and related approximations, i.e. the local density, the generalized gradient and their hybrid approximations.
In Brief: Hidden environment and health costs of energy
NASA Astrophysics Data System (ADS)
Showstack, Randy
2009-10-01
The hidden costs of energy production and use in the United States amounted to an estimated $120 billion in 2005, according to a 19 October report by the U.S. National Research Council. The report, “Hidden Costs of Energy: Unpriced Consequences of Energy Production and Use,” examines hidden costs, including the cost of air pollution damage to human health, which are not reflected in market prices of energy sources, electricity, or gasoline. The report found that in 2005, the total annual external damages from sulfur dioxide, nitrogen oxides, and particulate matter created by coal-burning power plants that produced 95% of the nation's coal-generated electricity were about $62 billion, with nonclimate damages averaging about 3.2 cents for every kilowatt-hour of energy produced. It is estimated that by 2030, nonclimate damages will fall to 1.7 cents per kilowatt-hour. The 2030 figure assumes that new policies already slated for implementation are put in place.
A hydrogen energy carrier. Volume 2: Systems analysis
NASA Technical Reports Server (NTRS)
Savage, R. L. (Editor); Blank, L. (Editor); Cady, T. (Editor); Cox, K. (Editor); Murray, R. (Editor); Williams, R. D. (Editor)
1973-01-01
A systems analysis of hydrogen as an energy carrier in the United States indicated that it is feasible to use hydrogen in all energy use areas, except some types of transportation. These use areas are industrial, residential and commercial, and electric power generation. Saturation concept and conservation concept forecasts of future total energy demands were made. Projected costs of producing hydrogen from coal or from nuclear heat combined with thermochemical decomposition of water are in the range $1.00 to $1.50 per million Btu of hydrogen produced. Other methods are estimated to be more costly. The use of hydrogen as a fuel will require the development of large-scale transmission and storage systems. A pipeline system similar to the existing natural gas pipeline system appears practical, if design factors are included to avoid hydrogen environment embrittlement of pipeline metals. Conclusions from the examination of the safety, legal, environmental, economic, political and societal aspects of hydrogen fuel are that a hydrogen energy carrier system would be compatible with American values and the existing energy system.
MEGASTAR: The Meaning of Energy Growth: An Assessment of Systems, Technologies, and Requirements
NASA Technical Reports Server (NTRS)
1974-01-01
A methodology for the display and analysis of postulated energy futures for the United States is presented. A systems approach that includes the methodology of technology assessment is used to examine three energy scenarios--the Westinghouse Nuclear Electric Economy, the Ford Technical Fix Base Case and a MEGASTAR generated Alternate to the Ford Technical Fix Base Case. The three scenarios represent different paths of energy consumption for the present to the year 2000. Associated with these paths are various mixes of fuels, conversion, distribution, conservation and end-use technologies. MEGASTAR presents the estimated times and unit requirements to supply the fuels, conversion and distribution systems for the postulated end uses for the three scenarios and then estimates the aggregate manpower, materials, and capital requirements needed to develop the energy system described by the particular scenario. The total requirements and the energy subsystems for each scenario are assessed for their primary impacts in the areas of society, the environment, technology and the economy.
A study of the kinetic energy generation with general circulation models
NASA Technical Reports Server (NTRS)
Chen, T.-C.; Lee, Y.-H.
1983-01-01
The history data of winter simulation by the GLAS climate model and the NCAR community climate model are used to examine the generation of atmospheric kinetic energy. The contrast between the geographic distributions of the generation of kinetic energy and divergence of kinetic energy flux shows that kinetic energy is generated in the upstream side of jets, transported to the downstream side and destroyed there. The contributions from the time-mean and transient modes to the counterbalance between generation of kinetic energy and divergence of kinetic energy flux are also investigated. It is observed that the kinetic energy generated by the time-mean mode is essentially redistributed by the time-mean flow, while that generated by the transient flow is mainly responsible for the maintenance of the kinetic energy of the entire atmospheric flow.
Yang, Hang; Zhang, Yongxin; Zheng, Chenghang; Wu, Xuecheng; Chen, Linghong; Gao, Xiang; Fu, Joshua S
2018-05-10
The pollutant abatement systems are widely applied in the coal-fired power sector and the energy consumption was considered an important part of the auxiliary power. An energy consumption analysis and assessment model of pollutant abatement systems in a power unit was developed based on the dynamic parameters and technology. The energy consumption of pollutant abatement systems in a 1000 MW coal-fired power unit which meet the ultra-low emission limits and the factors of operating parameters including unit load and inlet concentration of pollutants on the operating power were analyzed. The results show that the total power consumption of the pollutant abatement systems accounted for 1.27% of the gross power generation during the monitoring period. The WFGD system consumed 67% of the rate while the SCR and ESP systems consumed 8.9% and 24.1%. The power consumption rate of pollutant abatement systems decreased with the increase of unit load and increased with the increase of the inlet concentration of pollutants. The operation adjustment was also an effective method to increase the energy efficiency. For example, the operation adjustment of slurry circulation pumps could promote the energy-saving operation of WFGD system. Implication Statement The application of pollutant abatement technologies increases the internal energy consumption of the power plant, which will lead to an increase of power generation costs. The real-time energy consumption of the different pollutant abatement systems in a typical power unit is analyzed based on the dynamic operating data. Further, the influence of different operating parameters on the operating power of the system and the possible energy-saving potential are analyzed.
Antiproton powered propulsion with magnetically confined plasma engines
NASA Technical Reports Server (NTRS)
Lapointe, Michael R.
1989-01-01
Matter-antimatter annihilation releases more energy per unit mass than any other method of energy production, making it an attractive energy source for spacecraft propulsion. In the magnetically confined plasma engine, antiproton beams are injected axially into a pulsed magnetic mirror system, where they annihilate with an initially neutral hydrogen gas. The resulting charged annihilation products transfer energy to the hydrogen propellant, which is then exhausted through one end of the pulsed mirror system to provide thrust. The calculated energy transfer efficiencies for a low number density (10(14)/cu cm) hydrogen propellant are insufficient to warrant operating the engine in this mode. Efficiencies are improved using moderate propellant number densities (10(16)/cu cm), but the energy transferred to the plasma in a realistic magnetic mirror system is generally limited to less than 2 percent of the initial proton-antiproton annihilation energy. The energy transfer efficiencies are highest for high number density (10(18)/cu cm) propellants, but plasma temperatures are reduced by excessive radiation losses. Low to moderate thrust over a wide range of specific impulse can be generated with moderate propellant number densities, while higher thrust but lower specific impulse may be generated using high propellant number densities. Significant mass will be required to shield the superconducting magnet coils from the high energy gamma radiation emitted by neutral pion decay. The mass of such a radiation shield may dominate the total engine mass, and could severely diminish the performance of antiproton powered engines which utilize magnetic confinement. The problem is compounded in the antiproton powered plasma engine, where lower energy plasma bremsstrahlung radiation may cause shield surface ablation and degradation.
NASA Astrophysics Data System (ADS)
Li, Hongzhi; Min, Donghong; Liu, Yusong; Yang, Wei
2007-09-01
To overcome the possible pseudoergodicity problem, molecular dynamic simulation can be accelerated via the realization of an energy space random walk. To achieve this, a biased free energy function (BFEF) needs to be priori obtained. Although the quality of BFEF is essential for sampling efficiency, its generation is usually tedious and nontrivial. In this work, we present an energy space metadynamics algorithm to efficiently and robustly obtain BFEFs. Moreover, in order to deal with the associated diffusion sampling problem caused by the random walk in the total energy space, the idea in the original umbrella sampling method is generalized to be the random walk in the essential energy space, which only includes the energy terms determining the conformation of a region of interest. This essential energy space generalization allows the realization of efficient localized enhanced sampling and also offers the possibility of further sampling efficiency improvement when high frequency energy terms irrelevant to the target events are free of activation. The energy space metadynamics method and its generalization in the essential energy space for the molecular dynamics acceleration are demonstrated in the simulation of a pentanelike system, the blocked alanine dipeptide model, and the leucine model.
Modeling and Control of a Tailsitter with a Ducted Fan
NASA Astrophysics Data System (ADS)
Argyle, Matthew Elliott
There are two traditional aircraft categories: fixed-wing which have a long endurance and a high cruise airspeed and rotorcraft which can take-off and land vertically. The tailsitter is a type of aircraft that has the strengths of both platforms, with no additional mechanical complexity, because it takes off and lands vertically on its tail and can transition the entire aircraft horizontally into high-speed flight. In this dissertation, we develop the entire control system for a tailsitter with a ducted fan. The standard method to compute the quaternion-based attitude error does not generate ideal trajectories for a hovering tailsitter for some situations. In addition, the only approach in the literature to mitigate this breaks down for large attitude errors. We develop an alternative quaternion-based error method which generates better trajectories than the standard approach and can handle large errors. We also derive a hybrid backstepping controller with almost global asymptotic stability based on this error method. Many common altitude and airspeed control schemes for a fixed-wing airplane assume that the altitude and airspeed dynamics are decoupled which leads to errors. The Total Energy Control System (TECS) is an approach that controls the altitude and airspeed by manipulating the total energy rate and energy distribution rate, of the aircraft, in a manner which accounts for the dynamic coupling. In this dissertation, a nonlinear controller, which can handle inaccurate thrust and drag models, based on the TECS principles is derived. Simulation results show that the nonlinear controller has better performance than the standard PI TECS control schemes. Most constant altitude transitions are accomplished by generating an optimal trajectory, and potentially actuator inputs, based on a high fidelity model of the aircraft. While there are several approaches to mitigate the effects of modeling errors, these do not fully remove the accurate model requirement. In this dissertation, we develop two different approaches that can achieve near constant altitude transitions for some types of aircraft. The first method, based on multiple LQR controllers, requires a high fidelity model of the aircraft. However, the second method, based on the energy along the body axes, requires almost no aerodynamic information.
Bruderer, Tobias; Varesio, Emmanuel; Hidasi, Anita O; Duchoslav, Eva; Burton, Lyle; Bonner, Ron; Hopfgartner, Gérard
2018-03-01
High-quality mass spectral libraries have become crucial in mass spectrometry-based metabolomics. Here, we investigate a workflow to generate accurate mass discrete and composite spectral libraries for metabolite identification and for SWATH mass spectrometry data processing. Discrete collision energy (5-100 eV) accurate mass spectra were collected for 532 metabolites from the human metabolome database (HMDB) by flow injection analysis and compiled into composite spectra over a large collision energy range (e.g., 10-70 eV). Full scan response factors were also calculated. Software tools based on accurate mass and predictive fragmentation were specially developed and found to be essential for construction and quality control of the spectral library. First, elemental compositions constrained by the elemental composition of the precursor ion were calculated for all fragments. Secondly, all possible fragments were generated from the compound structure and were filtered based on their elemental compositions. From the discrete spectra, it was possible to analyze the specific fragment form at each collision energy and it was found that a relatively large collision energy range (10-70 eV) gives informative MS/MS spectra for library searches. From the composite spectra, it was possible to characterize specific neutral losses as radical losses using in silico fragmentation. Radical losses (generating radical cations) were found to be more prominent than expected. From 532 metabolites, 489 provided a signal in positive mode [M+H] + and 483 in negative mode [M-H] - . MS/MS spectra were obtained for 399 compounds in positive mode and for 462 in negative mode; 329 metabolites generated suitable spectra in both modes. Using the spectral library, LC retention time, response factors to analyze data-independent LC-SWATH-MS data allowed the identification of 39 (positive mode) and 72 (negative mode) metabolites in a plasma pool sample (total 92 metabolites) where 81 previously were reported in HMDB to be found in plasma. Graphical abstract Library generation workflow for LC-SWATH MS, using collision energy spread, accurate mass, and fragment annotation.
Koteja, P; Swallow, J G; Carter, P A; Garland, T
1999-01-01
Laboratory house mice (Mus domesticus) that had experienced 10 generations of artificial selection for high levels of voluntary wheel running ran about 70% more total revolutions per day than did mice from random-bred control lines. The difference resulted primarily from increased average velocities rather than from increased time spent running. Within all eight lines (four selected, four control), females ran more than males. Average daily running distances ranged from 4.4 km in control males to 11.6 km in selected females. Whole-animal food consumption was statistically indistinguishable in the selected and control lines. However, mice from selected lines averaged approximately 10% smaller in body mass, and mass-adjusted food consumption was 4% higher in selected lines than in controls. The incremental cost of locomotion (grams food/revolution), computed as the partial regression slope of food consumption on revolutions run per day, did not differ between selected and control mice. On a 24-h basis, the total incremental cost of running (covering a distance) amounted to only 4.4% of food consumption in the control lines and 7.5% in the selected ones. However, the daily incremental cost of time active is higher (15.4% and 13.1% of total food consumption in selected and control lines, respectively). If wheel running in the selected lines continues to increase mainly by increases in velocity, then constraints related to energy acquisition are unlikely to be an important factor limiting further selective gain. More generally, our results suggest that, in small mammals, a substantial evolutionary increase in daily movement distances can be achieved by increasing running speed, without remarkable increases in total energy expenditure.
State of energy consumption and CO2 emission in Bangladesh.
Azad, Abul K; Nashreen, S W; Sultana, J
2006-03-01
Carbon dioxide (CO2) is one of the most important gases in the atmosphere, and is necessary for sustaining life on Earth. It is also considered to be a major greenhouse gas contributing to global warming and climate change. In this article, energy consumption in Bangladesh is analyzed and estimates are made of CO2 emission from combustion of fossil fuel (coal, gas, petroleum products) for the period 1977 to 1995. International Panel for Climate Change guidelines for national greenhouse gas inventories were used in estimating CO2 emission. An analysis of energy data shows that the consumption of fossil fuels in Bangladesh is growing by more than 5% per year. The proportion of natural gas in total energy consumption is increasing, while that of petroleum products and coal is decreasing. The estimated total CO2 release from all primary fossil fuels used in Bangladesh amounted to 5072 Gigagram (Gg) in 1977, and 14 423 Gg in 1995. The total amounts of CO2 released from petroleum products, natural gas, and coal in the period 1977-1995 were 83 026 Gg (50% of CO2 emission), 72 541 Gg (44% of CO2 emission), and 9545 Gg (6% CO2 emission), respectively. A trend in CO2 emission with projections to 2070 is generated. In 2070, total estimated CO2 emission will be 293 260 Gg with a current growth rate of 6.34% y . CO2 emission from fossil fuels is increasing. Petroleum products contribute the majority of CO2 emission load, and although the use of natural gas is increasing rapidly, its contribution to CO2 emission is less than that of petroleum products. The use of coal as well as CO2 emission from coal is expected to gradually decrease.
Distributed photovoltaic system impact upon utility load/supply management practices
NASA Astrophysics Data System (ADS)
Vachtsevanos, G. J.; Meliopoulos, A. P.; Paraskevopoulos, B. K.
A methodology is described for simulation of the economic and technical factors of photovoltaic (PV) installations interfacing with utility load/management operations. A probabalistic technique is used to model the expected demand, reliability of the generating units, costs and profits from each unit, expected unserviced energy, and the loss of load probability. The available power from PV arrays is treated stochastically with statistical weighting on the basis of site meteorological data. The goal is to include the PV power while minimizing operational costs, taking into account the level of penetration of the total PV output. Two sample simulations for a utility with a diverse generating mix demonstrate that overall costs would decrease in both cases with PVs on-line through the emphasis on cheaper-fueled generators and peak-load shaving when possible.
Mid-infrared supercontinuum generation in tapered As2S3 chalcogenide planar waveguide
NASA Astrophysics Data System (ADS)
Zhang, Xiang; Hu, Hongyu; Li, Wenbo; Dutta, Niloy K.
2016-10-01
We numerically demonstrate mid-infrared supercontinuum generation in a non-uniformly tapered chalcogenide planar waveguide. This planar rib waveguide of As2S3 glass on MgF2 is 2 cm long with increasing etch depth longitudinally to manage the total dispersion. This waveguide has zero dispersion at two wavelengths. The dispersion profile varies along the propagation distance, leading to continuous modification of the phase-matching condition for dispersive wave emission and enhancement of energy transfer efficiency between solitons and dispersive waves. Numerical simulations are conducted for secant input pulses at a wavelength of 1.55 μm with a width of 50 fs and peak power of 2 kW. Results show this proposed scheme significantly broadens the generated continuum, extending from ~1 to ~7 μm.
Experimental comparison of PV-smoothing controllers using distributed generators
DOE Office of Scientific and Technical Information (OSTI.GOV)
Johnson, Jay Dean; Ellis, Abraham; Denda, Atsushi
The power output variability of photovoltaic systems can affect local electrical grids in locations with high renewable energy penetrations or weak distribution or transmission systems. In those rare cases, quick controllable generators (e.g., energy storage systems) or loads can counteract the destabilizing effects by compensating for the power fluctuations. Previously, control algorithms for coordinated and uncoordinated operation of a small natural gas engine-generator (genset) and a battery for smoothing PV plant output were optimized using MATLAB/Simulink simulations. The simulations demonstrated that a traditional generation resource such as a natural gas genset in combination with a battery would smooth the photovoltaicmore » output while using a smaller battery state of charge (SOC) range and extending the life of the battery. This paper reports on the experimental implementation of the coordinated and uncoordinated controllers to verify the simulations and determine the differences in the controllers. The experiments were performed with the PNM PV and energy storage Prosperity site and a gas engine-generator located at the Aperture Center at Mesa Del Sol in Albuquerque, New Mexico. Two field demonstrations were performed to compare the different PV smoothing control algorithms: (1) implementing the coordinated and uncoordinated controls while switching off a subsection of the PV array at precise times on successive clear days, and (2) comparing the results of the battery and genset outputs for the coordinated control on a high variability day with simulations of the coordinated and uncoordinated controls. It was found that for certain PV power profiles the SOC range of the battery may be larger with the coordinated control, but the total amp-hours through the battery-which approximates battery wear-will always be smaller with the coordinated control.« less
Installation of a Low Flow Unit at the Abiquiu Hydroelectric Facility
DOE Office of Scientific and Technical Information (OSTI.GOV)
Jack Q. Richardson
2012-06-28
Final Technical Report for the Recovery Act Project for the Installation of a Low Flow Unit at the Abiquiu Hydroelectric Facility. The Abiquiu hydroelectric facility existed with two each 6.9 MW vertical flow Francis turbine-generators. This project installed a new 3.1 MW horizontal flow low flow turbine-generator. The total plant flow range to capture energy and generate power increased from between 250 and 1,300 cfs to between 75 and 1,550 cfs. Fifty full time equivalent (FTE) construction jobs were created for this project - 50% (or 25 FTE) were credited to ARRA funding due to the ARRA 50% project costmore » match. The Abiquiu facility has increased capacity, increased efficiency and provides for an improved aquatic environment owing to installed dissolved oxygen capabilities during traditional low flow periods in the Rio Chama. A new powerhouse addition was constructed to house the new turbine-generator equipment.« less
An university-scale pulsed-power system using a bipolar Marx generator
NASA Astrophysics Data System (ADS)
Chang, Po-Yu; Yang, Sheng-Hua; Huang, Mei-Feng; Isaps, Natl Cheng Kung Univ Team
2017-10-01
A bipolar Marx generator is being built for x-ray sources or laboratory astrophysics and space research for university-scale laboratory. The system consists of ten stages. In each stage, two 1 μF capacitors connected in series are charged to +/- 30 kV storing 9 kJ of total energy. It delivers a current of 200 kA to the load with a 200 ns rise time during the discharge. It will be used for following three purposes: (1) gas-puff z pinches generating soft x-ray for bio-medical research in the future; (2) generating plasma jets to study interactions between plasma flows and unmagnetized/magnetized obstacles analogous to the interactions between solar winds and planetary magnetic fields or unmagnetized planets; and (3) studying the pinch in a dense plasma focus device. The results of current measurements and circuit characteristics are shown.
Rasapoor, Mazdak; Adl, Mehrdad; Baroutian, Saeid; Iranshahi, Zeynab; Pazouki, Mohammad
2018-04-30
It has been proven that ultrasonic pretreatment (UP) has positive effect on biogas generation from previous lab-scale studies. However, that is not always the case in larger scale processes. The purpose of this study was to evaluate the effectiveness of UP to biogas generation in terms of anaerobic digestion process and energy efficiency. Parameters including total solids (TS) and ultrasonic treatment operational parameters of organic solid waste (OSW) resulted from our past lab scale UP studies were applied in this study. OSW with 6-10% TS was treated using a lab-scale ultrasonic processor using various power densities (0.2-0.6 W/mL) at different time periods up to 30 min. Results of lab scale confirmed that OSW with 6% TS sonicated with 0.2 W/mL power density in 30 min gave the best outcome for the pilot scale experiment. To simulate the condition of an actual scale, in addition to energy analysis, two different organic loading rates (OLR), namely 500 and 1500 gVS/m 3 day were examined. The pilot digester was fed with OSW with or without the pretreatment based on the aforementioned specifications. The results showed that UP effectively improves biogas generation in terms of quantity and quality (CH 4 /CO 2 ). Furthermore, it decreases the time to reach the maximum cumulative biogas volume comparing to the untreated feed. The key achievement of this research has confirmed that although the relative increase in the energy gain by the influence of UP was more remarkable under the 500 gVS/m 3 day OLR, energy analysis showed a better energy gain and energy benefit as well as jumping in biogas yield up to 80% for UP treated OSW under 1500 gVS/m 3 day OLR. Copyright © 2018 Elsevier B.V. All rights reserved.
Valuation of Electric Power System Services and Technologies
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kintner-Meyer, Michael C. W.; Homer, Juliet S.; Balducci, Patrick J.
Accurate valuation of existing and new technologies and grid services has been recognized to be important to stimulate investment in grid modernization. Clear, transparent, and accepted methods for estimating the total value (i.e., total benefits minus cost) of grid technologies and services are necessary for decision makers to make informed decisions. This applies to home owners interested in distributed energy technologies, as well as to service providers offering new demand response services, and utility executives evaluating best investment strategies to meet their service obligation. However, current valuation methods lack consistency, methodological rigor, and often the capabilities to identify and quantifymore » multiple benefits of grid assets or new and innovative services. Distributed grid assets often have multiple benefits that are difficult to quantify because of the locational context in which they operate. The value is temporally, operationally, and spatially specific. It varies widely by distribution systems, transmission network topology, and the composition of the generation mix. The Electric Power Research Institute (EPRI) recently established a benefit-cost framework that proposes a process for estimating multiple benefits of distributed energy resources (DERs) and the associated cost. This document proposes an extension of this endeavor that offers a generalizable framework for valuation that quantifies the broad set of values for a wide range of technologies (including energy efficiency options, distributed resources, transmission, and generation) as well as policy options that affect all aspects of the entire generation and delivery system of the electricity infrastructure. The extension includes a comprehensive valuation framework of monetizable and non-monetizable benefits of new technologies and services beyond the traditional reliability objectives. The benefits are characterized into the following categories: sustainability, affordability, and security, flexibility, and resilience. This document defines the elements of a generic valuation framework and process as well as system properties and metrics by which value streams can be derived. The valuation process can be applied to determine the value on the margin of incremental system changes. This process is typically performed when estimating the value of a particular project (e.g., value of a merchant generator, or a distributed photovoltaic (PV) rooftop installation). Alternatively, the framework can be used when a widespread change in the grid operation, generation mix, or transmission topology is to be valued. In this case a comprehensive system analysis is required.« less
Electricity and generator availability in LMIC hospitals: improving access to safe surgery.
Chawla, Sagar; Kurani, Shaheen; Wren, Sherry M; Stewart, Barclay; Burnham, Gilbert; Kushner, Adam; McIntyre, Thomas
2018-03-01
Access to reliable energy has been identified as a global priority and codified within United Nations Sustainable Goal 7 and the Electrify Africa Act of 2015. Reliable hospital access to electricity is necessary to provide safe surgical care. The current state of electrical availability in hospitals in low- and middle-income countries (LMICs) throughout the world is not well known. This study aimed to review the surgical capacity literature and document the availability of electricity and generators. Using Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, a systematic search for surgical capacity assessments in LMICs in MEDLINE, PubMed, and World Health Organization Global Health Library was performed. Data regarding electricity and generator availability were extracted. Estimated percentages for individual countries were calculated. Of 76 articles identified, 21 reported electricity availability, totaling 528 hospitals. Continuous electricity availability at hospitals providing surgical care was 312/528 (59.1%). Generator availability was 309/427 (72.4%). Estimated continuous electricity availability ranged from 0% (Sierra Leone and Malawi) to 100% (Iran); estimated generator availability was 14% (Somalia) to 97.6% (Iran). Less than two-thirds of hospitals providing surgical care in 21 LMICs have a continuous electricity source or have an available generator. Efforts are needed to improve electricity infrastructure at hospitals to assure safe surgical care. Future research should look at the effect of energy availability on surgical care and patient outcomes and novel methods of powering surgical equipment. Copyright © 2017 Elsevier Inc. All rights reserved.
Potential for electricity generation from biomass residues in Cuba
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lora, E.S.
The purpose of this paper is the study of the availability of major biomass residues in Cuba and the analysis of the electricity generation potential by using different technologies. An analysis of the changes in the country`s energy balance from 1988 up to date is presented, as well as a table with the availability study results and the energy equivalent for the following biomass residues: sugar cane bagasse and trash, rice and coffee husk, corn an cassava stalks and firewood. A total equivalent of 4.42 10{sup 6} tons/year of fuel-oil was obtained. Possible scenarios for the electricity production increase inmore » the sugar industry are presented too. The analysis is carried out for a high stream parameter CEST and two BIG/GT system configurations. Limitations are introduced about the minimal milling capacity of the sugar mills for each technology. The calculated {open_quotes}real{close_quotes} electricity generation potential for BIG/GT systems, based on GE LM5000 CC gas turbines, an actual cane harvest of 58.0 10{sup 6} tons/year, half the available trash utilization and an specific steam consumption of 210 kg/tc, was 18601,0 GWh/year. Finally different alternatives are presented for low-scale electricity generation based on the other available agricultural residues.« less
NASA Astrophysics Data System (ADS)
Mehrangiz, M.; Ghasemizad, A.
2017-06-01
Deuteron fast ignition of a conically guided pre-compressed DT fuel is investigated. For this purpose, the acceleration of the deuterated thin foil by the intense laser beam is evaluated. The acceleration values and the number of foil-generated deuterons are calculated in terms of the laser pulse duration. Using the created deuterons as the fast ignitors, we investigate the fast ignition scheme by comparing fully degenerate, partial degenerate and classical types of DT plasma. The total energy gain of deuterons "beam fusion" is calculated to show the efficiency of beam reactions in increasing fusion rate. Besides, the stopping time and stopping range of incident deuterons are evaluated. Our numerical results indicate that degeneracy increases the beam-target collisions. Thus, it prepares the ignition situation sooner than the classical plasma. Moreover, the number of generated deuterons and their acceleration depend on the foil thickness and laser parameters. We show that when a 4ps laser with intensity of 10^{19} W/cm^2 focused onto a 20μm foil, 35× 10^{15} deuterons are generated. Moreover, under our analysis, in order to have a practicable fast ignition, 18% of the laser energy is necessary to convert into a deuteron driver.
Reactive power planning under high penetration of wind energy using Benders decomposition
Xu, Yan; Wei, Yanli; Fang, Xin; ...
2015-11-05
This study addresses the optimal allocation of reactive power volt-ampere reactive (VAR) sources under the paradigm of high penetration of wind energy. Reactive power planning (RPP) in this particular condition involves a high level of uncertainty because of wind power characteristic. To properly model wind generation uncertainty, a multi-scenario framework optimal power flow that considers the voltage stability constraint under the worst wind scenario and transmission N 1 contingency is developed. The objective of RPP in this study is to minimise the total cost including the VAR investment cost and the expected generation cost. Therefore RPP under this condition ismore » modelled as a two-stage stochastic programming problem to optimise the VAR location and size in one stage, then to minimise the fuel cost in the other stage, and eventually, to find the global optimal RPP results iteratively. Benders decomposition is used to solve this model with an upper level problem (master problem) for VAR allocation optimisation and a lower problem (sub-problem) for generation cost minimisation. Impact of the potential reactive power support from doubly-fed induction generator (DFIG) is also analysed. Lastly, case studies on the IEEE 14-bus and 118-bus systems are provided to verify the proposed method.« less
NASA Astrophysics Data System (ADS)
Wong, Chin Hong; Dahari, Zuraini; Jumali, Mohammad Hafizuddin; Mohamed, Khairudin; Mohamed, Julie Juliewatty
2017-03-01
Harvesting vibrational energy from impacting raindrops using piezoelectric material has been proven to be a promising approach for future outdoor applications, providing a good alternative resource that can be applied in outdoor rainy environments. We present herein an optimum novel polyvinylidene fluoride (PVDF) piezoelectric transducer specifically developed to harvest raindrop energy. The finite-element method was applied for simulation and optimization of the piezoelectric raindrop energy harvester (PREH) using COMSOL Multiphysics software, investigating the electrical potential, surface charge density, and total displacement for different transducer dimensions. According to the simulation results, the structure that generated the highest electrical potential and surface charge density was a wagon-wheel-shaped structure consisting of six spokes with wheel diameter of 30 mm, spoke width of 2 mm, center pad diameter of 6 mm, and thickness of 25 μm. This optimum wagon-wheel-shaped device was then fabricated by spin coating of PVDF, sputtering of aluminum, a poling process, and computer numerical control machining of a polytetrafluoroethylene stand. The fabricated PREH was characterized by x-ray diffraction analysis and Fourier-transform infrared spectroscopy. Finally, the fabricated PREH was tested under actual rain conditions with an alternating current to direct current converter connected in parallel, revealing that a single cell could generate average peak voltage of 22.5 mV and produce electrical energy of 3.4 nJ from ten impacts in 20 s.
Regulation and competition without privatization: Norway`s experience
DOE Office of Scientific and Technical Information (OSTI.GOV)
Moen, J.; Hamrin, J.
The competitive market for the hydro-based Norwegian electricity system is working well, with end-user prices only slightly above the wholesale market. Pool prices are reflecting only weather-related variations, and no market power abuses are evident. The challenge now is to restructure ownership of the wires and retail suppliers to lower wheeling costs and avoid cross-subsidization. Since the Norwegian Energy Act came into effect in 1991, the electricity industry in Norway has operated as one of the most deregulated electricity industries in the world. The Energy Act introduced third party access to the retail market and competition in electricity production. Themore » generation, sale and purchase of electricity is now highly competitive, with customers free to buy electricity from any generator, trader or the electricity Pool. Transmission pricing was separated from power purchasing arrangements, so that the buying and selling of electricity as a product is distinct from the transmission of electricity as a service. Transmission and distribution networks continue to maintain natural monopolies, with network owners providing wheeling service across their networks to customers who are connected to them. These monopoly sectors of the industry are subject to regulation by the government-appointed regulatory body, Norwegian Water Resources and Energy Administration (NVE). Regulation is on a cost-of-service basis, with the revenue allowance determined by NVE. The main force behind the Norwegian reform was the desire for efficiency gains to be achieved through a total restructure of the commercial character of the energy service industry (ESI). Unlike the U.K., in Norway the monopoly franchise for both generation and retail supply was removed in one step without any transition period, and the old pool was reformed to provide the needed structure for this new competitive energy market.« less
California energy flow in 1993
DOE Office of Scientific and Technical Information (OSTI.GOV)
Borg, I.Y.; Briggs, C.K.
1995-04-01
Energy consumption in the state of California decreased about 3% in 1993 reflecting continuation of the recession that was manifest in a moribund construction industry and a high state unemployment that ran counter to national recovery trends. Residential/commercial use decreased slightly reflecting a mild winter in the populous southern portion of the state, a decrease that was offset to some extent by an increase in the state population. Industrial consumption of purchased energy declined substantially as did production of self-generated electricity for in-house use. Consumption in the transportation sector decreased slightly. The amount of power transmitted by the utilities wasmore » at 1992 levels; however a smaller proportion was produced by the utilities themselves. Generation of electricity by nonutilities, primarily cogenerators and small power producers, was the largest of any state in the US. The growth in the number of private power producers combined with increased amounts of electricity sold to the public utilities set the stage for the sweeping proposals before the California Public Utility Commission to permit direct sales from the nonutilities to retail customers. California production of both oil and natural gas declined; however, to meet demand only the imports of natural gas increased. A break in the decade-long drought during the 1992--1993 season resulted in a substantial increase in the amount of hydroelectricity generated during the year. Geothermal energy`s contribution increased substantially because of the development of new resources by small power producers. Decline in steam production continued at The Geysers, the state`s largest field, principally owned and managed by a public utility. Increases in windpower constituted 1--1/2% of the total electric supply--up slightly from 1992. Several solar photo voltaic demonstration plants were in operation, but their contribution remained small.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Myers, S.; Picasso, E.
This year the LEP (Large Electron-Positron) is expected to generate about a million more Z{sup 0}'s. This abundance of data will enable physicists to investigate rare decay modes, determine the precise mass and lifetime of the Z{sup 0}, study the processes underlying the production of hadrons (particles made up of quarks) and probe subtle aspects of the prevailing theory. Equally important, experiments at the LEP will try to discover new states of matter--in particular, the Higgs boson and perhaps also the top quark. Both of these massive particles are predicted by theory but have yet to be observed. Experimenters willmore » also be searching for phenomena that are not predicted by existing theories. The LEP Collider is destined to be the preeminent tool for particle physics in the next decade. Its spectacular performance to data is a tribute to the ingenuity and determined effort of hundreds of technicians, engineers and scientists from more than 25 nations who collaborated on the LEP and its detectors. With an average diameter of 8,486 meters and a beam-collision energy of 100 billion electron volts, or gigaelectron volts (GeV), the LEP is the largest and most powerful electron-positron storage ring ever built. Because the electrons and positrons have the same energy and are colliding head-on, the total energy available in the center of mass of the system is simply twice the beam energy. The LEP, with present collision energies of up to 110 GeV, generates Z{sup 0} particles. It will eventually be upgraded to 200 GeV and generate particles known as the W{sup +} and W{sup {minus}}. Each of these three particles weighs about 90 GeV, or about 100 times the mass of the proton.« less
A study on the power generation potential of mini wind turbine in east coast of Peninsular Malaysia
NASA Astrophysics Data System (ADS)
Basrawi, Firdaus; Ismail, Izwan; Ibrahim, Thamir Khalil; Idris, Daing Mohamad Nafiz Daing; Anuar, Shahrani
2017-03-01
A small-scale wind turbine is an attractive renewable energy source, but its economic viability depends on wind speed. The aim of this study is to determine economic viability of small-scale wind turbine in East Coast of Peninsular Malaysia. The potential energy generated has been determined by wind speed data and power curved of. Hourly wind speed data of Kuantan throughout 2015 was collected as the input. Then, a model of wind turbine was developed based on a commercial a 300W mini wind turbine. It was found that power generation is 3 times higher during northeast monsoon season at 15 m elevation. This proved that the northeast monsoon season has higher potential in generating power by wind turbine in East Coast of Peninsular Malaysia. However, only a total of 153.4 kWh/year of power can be generated at this condition. The power generator utilization factor PGUI or capacity ratio was merely 0.06 and it is not technically viable. By increasing the height of wind turbine to 60 m elevation, power generation amount drastically increased to 344 kWh/year, with PGUI of 0.13. This is about two-thirds of PGUI for photovoltaic technology which is 0.21 at this site. If offshore condition was considered, power generation amount further increased to 1,328 kWh/year with PGUI of 0.51. Thus, for a common use of mini wind turbine that is usually installed on-site at low elevation, it has low power generation potential. But, if high elevation as what large wind turbine needed is implemented, it is technically viable option in East Coast of Peninsular Malaysia.
Zhu, Meiling; Worthington, Emma; Tiwari, Ashutosh
2010-01-01
This paper presents a design study on the geometric parameters of a cantilever-based piezoelectric energy-harvesting devices (EHD), which harvest energy from motion (vibration), for the purpose of scavenging more energy from ambient vibration energy sources. The design study is based on the coupled piezoelectric-circuit finite element method (CPCFEM), previously presented by Dr. Zhu. This model can calculate the power output of piezoelectric EHDS directly connected to a load resistor and is used in this paper to obtain the following simulation results for variations in geometric parameters such as the beam length, width and thickness, and the mass length, width, and height: 1) the current flowing through and the voltage developed across the load resistor, 2) the power dissipated by the resistor and the corresponding vibrational displacement amplitude, and 3) the resonant frequency. By studying these results, straightforward design strategies that enable the generation of more power are obtained for each geometric parameter, and a physical understanding of how each parameter affects the output power is given. It is suggested that, in designing with the aim of generating more power, the following strategies be used: 1) for the beam, a shorter length, larger width, and lower ratio of piezoelectric layer thickness to total beam thickness are preferred in the case of a fixed mass; 2) for the mass, a shortened mass length and a higher mass height are preferred in the case of variation in the mass length and the mass height with mass width and mass value remain fixed, and a wider width and small mass height are preferred in the case of variation in mass width and height (mass length and value remain fixed; and 3) for the case of a fixed total length, a shorter beam length and longer mass length are preferred. With the design strategies, output powers from the device can reach above 1 to 2 mW/cm(3), much higher than the 200 microW/cm(3) currently achieved in the published literature. This is an encouraging prospect for enabling a wider range of applications of the EHDs. In addition, physical insights into how each parameter influences output power are also discussed in detail.
Research on Efficiency of a Wave Energy Conversion System
NASA Astrophysics Data System (ADS)
Lu, Zhongyue; Shang, Jianzhong; Luo, Zirong; Sun, Chongfei; Chen, Gewei
2018-02-01
The oceans are rich in wave energy that is green energy, and the wave energy are now being used to generate electricity on a massive scale. It can also be used as a single generator for beacon, buoy or underwater vehicle. Micro small wave energy power generation device is a kind of wave energy power generation devices, main characteristic is mobility is good, and can be directly assembled on various kinds of equipment for the power supply, with good prospects for development. The research object of the paper is a new adaptive reversing wave energy generating device belongs to micro-sized wave energy generating device. Using the upper and lower absorber blade groups, the low speed and large torque wave energy can be converted into electric energy which can be used for load and lithium battery charging.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sun, Kaiyu; Yan, Da; Hong, Tianzhen
2014-02-28
Overtime is a common phenomenon around the world. Overtime drives both internal heat gains from occupants, lighting and plug-loads, and HVAC operation during overtime periods. Overtime leads to longer occupancy hours and extended operation of building services systems beyond normal working hours, thus overtime impacts total building energy use. Current literature lacks methods to model overtime occupancy because overtime is stochastic in nature and varies by individual occupants and by time. To address this gap in the literature, this study aims to develop a new stochastic model based on the statistical analysis of measured overtime occupancy data from an officemore » building. A binomial distribution is used to represent the total number of occupants working overtime, while an exponential distribution is used to represent the duration of overtime periods. The overtime model is used to generate overtime occupancy schedules as an input to the energy model of a second office building. The measured and simulated cooling energy use during the overtime period is compared in order to validate the overtime model. A hybrid approach to energy model calibration is proposed and tested, which combines ASHRAE Guideline 14 for the calibration of the energy model during normal working hours, and a proposed KS test for the calibration of the energy model during overtime. The developed stochastic overtime model and the hybrid calibration approach can be used in building energy simulations to improve the accuracy of results, and better understand the characteristics of overtime in office buildings.« less
NASA Astrophysics Data System (ADS)
Yukita, Kazuto; Ichiyanagi, Katsuhiro; Mori, Tsuyoshi; Goto, Yasuyuki
This paper discusses the methods of implementation and improvement adopted in the energy education program of “Marugoto Taiken World” (“Total Experience World”) at Aichi Institute of Technology. The program, which is aimed at high school, junior high school and elementary school students, has been carried on at Aichi Institute of Technology for a number of years now, and the authors have been involved in the energy education project for the past four years. During that time, the following four courses have been held : 1) Let's use wind power to generate electricity, 2) Let's use flowers to build a solar battery, 3) Let's use bottles to build a fuel cell battery, 4) Let's make all sorts of batteries.
Final Technical Report. DeepCwind Consortium Research Program. January 15, 2010 - March 31, 2013
DOE Office of Scientific and Technical Information (OSTI.GOV)
Dagher, Habib; Viselli, Anthony; Goupee, Andrew
This is the final technical report for the U.S. Department of Energy-funded program, DE-0002981: DeepCwind Consortium Research Program. The project objective was the partial validation of coupled models and optimization of materials for offshore wind structures. The United States has a great opportunity to harness an indigenous abundant renewable energy resource: offshore wind. In 2010, the National Renewable Energy Laboratory (NREL) estimated there to be over 4,000 GW of potential offshore wind energy found within 50 nautical miles of the US coastlines (Musial and Ram, 2010). The US Energy Information Administration reported the total annual US electric energy generation inmore » 2010 was 4,120 billion kilowatt-hours (equivalent to 470 GW) (US EIA, 2011), slightly more than 10% of the potential offshore wind resource. In addition, deep water offshore wind is the dominant US ocean energy resource available comprising 75% of the total assessed ocean energy resource as compared to wave and tidal resources (Musial, 2008). Through these assessments it is clear offshore wind can be a major contributor to US energy supplies. The caveat to capturing offshore wind along many parts of the US coast is deep water. Nearly 60%, or 2,450 GW, of the estimated US offshore wind resource is located in water depths of 60 m or more (Musial and Ram, 2010). At water depths over 60 m building fixed offshore wind turbine foundations, such as those found in Europe, is likely economically infeasible (Musial et al., 2006). Therefore floating wind turbine technology is seen as the best option for extracting a majority of the US offshore wind energy resource. Volume 1 - Test Site; Volume 2 - Coupled Models; and Volume 3 - Composite Materials« less
Economically Feasible Potentials for Wind Power in China and the US
NASA Astrophysics Data System (ADS)
Lu, X.; McElroy, M. B.; Chris, N. P.; Tchou, J.
2011-12-01
The present study is intended to explore the economic feasible potentials for wind energy in China and the U.S. subject to their policy systems for renewable energy. These two countries were chosen as subject locales for three reasons: first, they are the two largest countries responsible for energy consumption and CO2 emissions; second, these two countries have the largest installed capacities and the fastest annual growth of wind power in the world; third, China and the U.S. have adopted two distinct but representative incentive policies to accelerate exploitation of the renewable energy source from wind. Investments in large-scale wind farms in China gain privileges from the concession policy established under China's Renewable Energy Law. The electricity generated from wind can be sold at a guaranteed price for a concession period (typically the first ten operational years of a wind farm) to ensure the profitability of the wind farm development. The effectiveness of this policy has been evidenced by the swift growth of total installed capacities for wind power over the past five years in China. A spatial financial model was developed to evaluate the bus-bar prices of wind-generated electricity in China following this wind concession policy. The results indicated that wind could accommodate all of the demand for electricity projected for 2030 assuming a guaranteed bus-bar price of 7.6 U.S. Cents per kWh over the concession period. It is noteworthy that the prices of wind-generated electricity could be as cheap as conventional power generation in the years following the concession period. The power market in the U.S. is more deregulated and electricity is normally traded in a bidding process an hour to a day ahead of real time. Accordingly, the market-oriented policy instrument of PTC subsidies was instituted in the U.S. to ensure the competitiveness of wind power compared to the conventional power generation in the regional power markets. The spatial financial model developed for previous analysis of wind energy in China was tailored to simulate the relevant investment environments for U.S. wind projects. A particular problem was investigated as to how the profitability and competitiveness of onshore wind power in the U.S. would be influenced by PTC subsidy levels varying from 0 to 4 cents per kWh. The results suggested that the current PTC level (2.1 cent per kWh) is at a critical point in determining the competitiveness of wind-generated electricity under normal costs. Setting system integration challenges aside, the potential for profitable wind-generated electricity could accommodate more than seven times U.S. electricity demand at the current PTC subsidy. Similar to the concession policy adopted in China, PTC subsidies are only available for the first ten years following the initiation of wind farms; wind power would still offer a renewable energy source for profitable electricity generation during the post-PTC period.
NASA Astrophysics Data System (ADS)
Winterberg, Friedwardt
2009-05-01
The recently proposed Super Marx pure deuterium micro-detonation ignition concept [1] is compared to the Lawrence Livermore National Ignition Facility (NIF) laser DT fusion-fission hybrid concept (LIFE) [2]. A typical example of the LIFE concept is a fusion gain 30, and a fission gain of 10, making up for a total gain of 300, with about 10 times more energy released into fission as compared to fusion. This means a substantial release of fission products, as in fusion-less pure fission reactors. In the Super Marx approach for the ignition of a pure deuterium micro-detonation gains of the same magnitude can in theory be reached. If the theoretical prediction can be supported by more elaborate calculations, the Super Marx approach is likely to make lasers obsolete as a means for the ignition of thermonuclear micro-explosions. [1] ``Ignition of a Deuterium Micro-Detonation with a Gigavolt Super Marx Generator,'' Winterberg, F., Journal of Fusion Energy, Springer, 2008. http://www.springerlink.com/content/r2j046177j331241/fulltext.pdf. [2] ``LIFE: Clean Energy from Nuclear Waste,'' https://lasers.llnl.gov/missions/energy&_slash;for&_slash;the&_slash;future/life/
LeBrun, Alexander; Joglekar, Tejashree; Bieberich, Charles; Ma, Ronghui; Zhu, Liang
2016-01-01
The objective of this study was to identify an injection strategy leading to repeatable nanoparticle deposition patterns in tumours and to quantify volumetric heat generation rate distribution based on micro-CT Hounsfield unit (HU) in magnetic nanoparticle hyperthermia. In vivo animal experiments were performed on graft prostatic cancer (PC3) tumours in immunodeficient mice to investigate whether lowering ferrofluid infusion rate improves control of the distribution of magnetic nanoparticles in tumour tissue. Nanoparticle distribution volume obtained from micro-CT scan was used to evaluate spreading of the nanoparticles from the injection site in tumours. Heating experiments were performed to quantify relationships among micro-CT HU values, local nanoparticle concentrations in the tumours, and the ferrofluid-induced volumetric heat generation rate (q(MNH)) when nanoparticles were subject to an alternating magnetic field. An infusion rate of 3 µL/min was identified to result in the most repeatable nanoparticle distribution in PC3 tumours. Linear relationships have been obtained to first convert micro-CT greyscale values to HU values, then to local nanoparticle concentrations, and finally to nanoparticle-induced q(MNH) values. The total energy deposition rate in tumours was calculated and the observed similarity in total energy deposition rates in all three infusion rate groups suggests improvement in minimising nanoparticle leakage from the tumours. The results of this study demonstrate that micro-CT generated q(MNH) distribution and tumour physical models improve predicting capability of heat transfer simulation for designing reliable treatment protocols using magnetic nanoparticle hyperthermia.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Seiferlein, Katherine E.
A generation ago the Ford Foundation convened a group of experts to explore and assess the Nation’s energy future, and published their conclusions in A Time To Choose: America’s Energy Future (Cambridge, MA: Ballinger, 1974). The Energy Policy Project developed scenarios of U.S. potential energy use in 1985 and 2000. Now, with 1985 well behind us and 2000 nearly on the record books, it may be of interest to take a look back to see what actually happened and consider what it means for our future. The study group sketched three primary scenarios with differing assumptions about the growth ofmore » energy use. The Historical Growth scenario assumed that U.S. energy consumption would continue to expand by 3.4 percent per year, the average rate from 1950 to 1970. This scenario assumed no intentional efforts to change the pattern of consumption, only efforts to encourage development of our energy supply. The Technical Fix scenario anticipated a “conscious national effort to use energy more efficiently through engineering know-how." The Zero Energy Growth scenario, while not clamping down on the economy or calling for austerity, incorporated the Technical Fix efficiencies plus additional efficiencies. This third path anticipated that economic growth would depend less on energy-intensive industries and more on those that require less energy, i.e., the service sector. In 2000, total energy consumption was projected to be 187 quadrillion British thermal units (Btu) in the Historical Growth case, 124 quadrillion Btu in the Technical Fix case, and 100 quadrillion Btu in the Zero Energy Growth case. The Annual Energy Review 1999 reports a preliminary total consumption for 1999 of 97 quadrillion Btu (see Table 1.1), and the Energy Information Administration’s Short-Term Energy Outlook (April 2000) forecasts total energy consumption of 98 quadrillion Btu in 2000. What energy consumption path did the United States actually travel to get from 1974, when the scenarios were drawn, to the end of the century? What happened to the relationship between growth and energy consumption? How did the fuel mix change over this period? What are the effects of energy usage on our environment? What level of consumption will the United States—and the world—record in the Annual Energy Review 2025? We present this edition of the Annual Energy Review to help investigate these important questions and to stimulate and inform our thinking about what the future holds.« less
Submerged anaerobic membrane bioreactor for wastewater treatment and energy generation.
Bornare, J B; Adhyapak, U S; Minde, G P; Kalyan Raman, V; Sapkal, V S; Sapkal, R S
2015-01-01
Compared with conventional wastewater treatment processes, membrane bioreactors (MBRs) offer several advantages including high biodegradation efficiency, excellent effluent quality and smaller footprint. However, it has some limitations on account of its energy intensive operation. In recent years, there has been growing interest in use of anaerobic membrane bioreactors (AnMBRs) due to their potential advantages over aerobic systems, which include low sludge production and energy generation in terms of biogas. The aim of this study was to evaluate the performance of a submerged AnMBR for the treatment of synthetic wastewater having 4,759 mg/l chemical oxygen demand (COD). The COD removal efficiency was over 95% during the performance evaluation study. Treated effluent with COD concentration of 231 mg/l was obtained for 25.5 hours hydraulic retention time. The obtained total organic carbon concentrations in feed and permeate were 1,812 mg/l and 89 mg/l, respectively. An average biogas generation and yield were 25.77 l/d and 0.36 m3/kg COD, respectively. Evolution of trans-membrane pressure (TMP) as a function of time was studied and an average TMP of 15 kPa was found suitable to achieve membrane flux of 12.17 l/(m2h). Almost weekly back-flow chemical cleaning of the membrane was found necessary to control TMP within the permissible limit of 20 kPa.
New Insights on Tsunami Genesis and Energy Source
NASA Astrophysics Data System (ADS)
Song, Y. T.; Mohtat, A.; Yim, S. C.
2017-12-01
Conventional tsunami theories suggest that earthquakes with significant vertical motions are more likely to generate tsunamis. In tsunami models, the vertical seafloor elevation is directly transferred to the sea-surface as the only initial condition. However, evidence from the 2011 Tohoku earthquake indicates otherwise; the vertical seafloor uplift was only 3 5 meters, too small to account for the resultant tsunami. Surprisingly, the horizontal displacement was undeniably larger than anyone's expectation; about 60 meters at the frontal wedge of the fault plate, the largest slip ever recorded by in-situ instruments. The question is whether the horizontal motion of seafloor slopes had enhanced the tsunami to become as destructive as observed. In this study, we provide proof: (1) Combining various measurements from the 2011 Tohoku event, we show that the earthquake transferred a total energy of 3.1e+15 joule to the ocean, in which the potential energy (PE) due to the vertical seafloor elevation (including seafloor uplift/subsidence plus the contribution from the horizontal displacement) was less than a half, while the kinetic energy (KE) due to the horizontal displacement velocity of the continental slope contributed a majority portion; (2) Using two modern state-of-the-art wave flumes and a three-dimensional tsunami model, we have reproduced the source energy and tsunamis consistent with observations, including the 2004 Sumatra event. Based on the unified source energy formulation, we offer a competing theory to explain why some earthquakes generate destructive tsunamis, while others do not.
Gañan, J; González, J F; González-García, C M; Cuerda-Correa, E M; Macías-García, A
2006-03-01
In this work, a pyrolysis plant located in Valverde de Leganes, Badajoz (SW Spain) was studied. At present, only the solid phase obtained by pyrolysis finds an application as domestic fuel. In order to analyze the feasibility of a further energetic exploitation of the plant under study, the gases flowing through the chimneys were collected at different times throughout the pyrolysis process. Next, they were characterized and quantified by gas chromatography, the energy potential of each of the gases being determined. According to the results obtained in this study, a total energy potential of 5.6 x 10(7) MJ (i.e., 1.78 MW(t)) might be generated yearly. Hence, considering an overall process yield equal to 20%, up to 358 KW(e) would be produced. This power would supply enough electric energy to the industry, the remaining being added to the common electric network.
Interaction of two walkers: wave-mediated energy and force.
Borghesi, Christian; Moukhtar, Julien; Labousse, Matthieu; Eddi, Antonin; Fort, Emmanuel; Couder, Yves
2014-12-01
A bouncing droplet, self-propelled by its interaction with the waves it generates, forms a classical wave-particle association called a "walker." Previous works have demonstrated that the dynamics of a single walker is driven by its global surface wave field that retains information on its past trajectory. Here we investigate the energy stored in this wave field for two coupled walkers and how it conveys an interaction between them. For this purpose, we characterize experimentally the "promenade modes" where two walkers are bound and propagate together. Their possible binding distances take discrete values, and the velocity of the pair depends on their mutual binding. The mean parallel motion can be either rectilinear or oscillating. The experimental results are recovered analytically with a simple theoretical framework. A relation between the kinetic energy of the droplets and the total energy of the standing waves is established.
NASA Astrophysics Data System (ADS)
Aloulou, R.; De Peslouan, P.-O. Lucas; Mnif, H.; Alicalapa, F.; Luk, J. D. Lan Sun; Loulou, M.
2016-05-01
Energy Harvesting circuits are developed as an alternative solution to supply energy to autonomous sensor nodes in Wireless Sensor Networks. In this context, this paper presents a micro-power management system for multi energy sources based on a novel design of charge pump circuit to allow the total autonomy of self-powered sensors. This work proposes a low-voltage and high performance charge pump (CP) suitable for implementation in standard complementary metal oxide semiconductor (CMOS) technologies. The CP design was implemented using Cadence Virtuoso with AMS 0.35μm CMOS technology parameters. Its active area is 0.112 mm2. Consistent results were obtained between the measured findings of the chip testing and the simulation results. The circuit can operate with an 800 mV supply and generate a boosted output voltage of 2.835 V with 1 MHz as frequency.
Poster - 18: New features in EGSnrc for photon cross sections
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ali, Elsayed; Mainegra-Hing, Ernesto; Rogers, Davi
2016-08-15
Purpose: To implement two new features in the EGSnrc Monte Carlo system. The first is an option to account for photonuclear attenuation, which can contribute a few percent to the total cross section at the higher end of the energy range of interest to medical physics. The second is an option to use exact NIST XCOM photon cross sections. Methods: For the first feature, the photonuclear total cross sections are generated from the IAEA evaluated data. In the current, first-order implementation, after a photonuclear event, there is no energy deposition or secondary particle generation. The implementation is validated against deterministicmore » calculations and experimental measurements of transmission signals. For the second feature, before this work, if the user explicitly requested XCOM photon cross sections, EGSnrc still used its own internal incoherent scattering cross sections. These differ by up to 2% from XCOM data between 30 keV and 40 MeV. After this work, exact XCOM incoherent scattering cross sections are an available option. Minor interpolation artifacts in pair and triplet XCOM cross sections are also addressed. The default for photon cross section in EGSnrc is XCOM except for the new incoherent scattering cross sections, which have to be explicitly requested. The photonuclear, incoherent, pair and triplet data from this work are available for elements and compounds for photon energies from 1 keV to 100 GeV. Results: Both features are implemented and validated in EGSnrc.Conclusions: The two features are part of the standard EGSnrc distribution as of version 4.2.3.2.« less