NREL/PG&E Condensation System Increases Geothermal Power Plant Efficiency
. Geothermal power plants like The Geysers produce energy by collecting steam from underground reservoirs and NREL/PG&E Condensation System Increases Geothermal Power Plant Efficiency For more information world's largest producer of geothermal power has improved its power production efficiency thanks to a new
NASA Technical Reports Server (NTRS)
Amos, D. J.; Foster-Pegg, R. W.; Lee, R. M.
1976-01-01
The energy conversion efficiency of gas-steam turbine cycles was investigated for selected combined cycle power plants. Results indicate that it is possible for combined cycle gas-steam turbine power plants to have efficiencies several point higher than conventional steam plants. Induction of low pressure steam into the steam turbine is shown to improve the plant efficiency. Post firing of the boiler of a high temperature combined cycle plant is found to increase net power but to worsen efficiency. A gas turbine pressure ratio of 12 to 1 was found to be close to optimum at all gas turbine inlet temperatures that were studied. The coal using combined cycle plant with an integrated low-Btu gasifier was calculated to have a plant efficiency of 43.6%, a capitalization of $497/kW, and a cost of electricity of 6.75 mills/MJ (24.3 mills/kwh). This combined cycle plant should be considered for base load power generation.
Evaluation of parasitic consumption for a CSP plant
NASA Astrophysics Data System (ADS)
Ramorakane, Relebohile John; Dinter, Frank
2016-05-01
With the continuous development and desire to build alternative effective and efficient power plants, Concentrated Solar Power (CSP) plants (and more specifically the Parabolic Trough CSP Plants) have proven to be one of the alternative energy resources for the future. On this regard more emphasis and research is being employed to better this power plant technology, where one of the main challenges to these plants is to improve their efficiency by optimizing the parasitic load, wherein one of the major causes of the power plants' reduced overall efficiency arises from their parasitic load consumption. This project is therefore aimed at evaluating the parasitic load on Andasol 3 Power Plant, which is a 50 MW Parabolic Trough Power Plant with a 7.5 hours of full load storage system. It was hence determined that the total power plant's parasitic load consumption is about 12% in summer season and between 16% and 24% in winter season. In an effort to improve the power plant's efficiency, a couple of measures to reduce the parasitic load consumption were recommended, and also an alternative and cheaper source of parasitic load feeding plant, during the day (when the parasitic load consumption is highest) was proposed/recommended.
A program for the calculation of paraboloidal-dish solar thermal power plant performance
NASA Technical Reports Server (NTRS)
Bowyer, J. M., Jr.
1985-01-01
A program capable of calculating the design-point and quasi-steady-state annual performance of a paraboloidal-concentrator solar thermal power plant without energy storage was written for a programmable calculator equipped with suitable printer. The power plant may be located at any site for which a histogram of annual direct normal insolation is available. Inputs required by the program are aperture area and the design and annual efficiencies of the concentrator; the intercept factor and apparent efficiency of the power conversion subsystem and a polynomial representation of its normalized part-load efficiency; the efficiency of the electrical generator or alternator; the efficiency of the electric power conditioning and transport subsystem; and the fractional parasitic loses for the plant. Losses to auxiliaries associated with each individual module are to be deducted when the power conversion subsystem efficiencies are calculated. Outputs provided by the program are the system design efficiency, the annualized receiver efficiency, the annualized power conversion subsystem efficiency, total annual direct normal insolation received per unit area of concentrator aperture, and the system annual efficiency.
Martín-Gamboa, Mario; Iribarren, Diego; Dufour, Javier
2018-02-15
The energy sector is still dominated by the use of fossil resources. In particular, natural gas represents the third most consumed resource, being a significant source of electricity in many countries. Since electricity production in natural gas combined cycle (NGCC) plants provides some benefits with respect to other non-renewable technologies, it is often seen as a transitional solution towards a future low‑carbon power generation system. However, given the environmental profile and operational variability of NGCC power plants, their eco-efficiency assessment is required. In this respect, this article uses a novel combined Life Cycle Assessment (LCA) and dynamic Data Envelopment Analysis (DEA) approach in order to estimate -over the period 2010-2015- the environmental impact efficiencies of 20 NGCC power plants located in Spain. A three-step LCA+DEA method is applied, which involves data acquisition, calculation of environmental impacts through LCA, and the novel estimation of environmental impact efficiency (overall- and term-efficiency scores) through dynamic DEA. Although only 1 out of 20 NGCC power plants is found to be environmentally efficient, all plants show a relatively good environmental performance with overall eco-efficiency scores above 60%. Regarding individual periods, 2011 was -on average- the year with the highest environmental impact efficiency (95%), accounting for 5 efficient NGCC plants. In this respect, a link between high number of operating hours and high environmental impact efficiency is observed. Finally, preliminary environmental benchmarks are presented as an additional outcome in order to further support decision-makers in the path towards eco-efficiency in NGCC power plants. Copyright © 2017 Elsevier B.V. All rights reserved.
NASA Astrophysics Data System (ADS)
Kler, A. M.; Zakharov, Yu. B.; Potanina, Yu. M.
2017-05-01
The objects of study are the gas turbine (GT) plant and combined cycle power plant (CCPP) with opportunity for injection between the stages of air compressor. The objective of this paper is technical and economy optimization calculations for these classes of plants with water interstage injection. The integrated development environment "System of machine building program" was a tool for creating the mathematic models for these classes of power plants. Optimization calculations with the criterion of minimum for specific capital investment as a function of the unit efficiency have been carried out. For a gas-turbine plant, the economic gain from water injection exists for entire range of power efficiency. For the combined cycle plant, the economic benefit was observed only for a certain range of plant's power efficiency.
Reassessing the Efficiency Penalty from Carbon Capture in Coal-Fired Power Plants.
Supekar, Sarang D; Skerlos, Steven J
2015-10-20
This paper examines thermal efficiency penalties and greenhouse gas as well as other pollutant emissions associated with pulverized coal (PC) power plants equipped with postcombustion CO2 capture for carbon sequestration. We find that, depending on the source of heat used to meet the steam requirements in the capture unit, retrofitting a PC power plant that maintains its gross power output (compared to a PC power plant without a capture unit) can cause a drop in plant thermal efficiency of 11.3-22.9%-points. This estimate for efficiency penalty is significantly higher than literature values and corresponds to an increase of about 5.3-7.7 US¢/kWh in the levelized cost of electricity (COE) over the 8.4 US¢/kWh COE value for PC plants without CO2 capture. The results follow from the inclusion of mass and energy feedbacks in PC power plants with CO2 capture into previous analyses, as well as including potential quality considerations for safe and reliable transportation and sequestration of CO2. We conclude that PC power plants with CO2 capture are likely to remain less competitive than natural gas combined cycle (without CO2 capture) and on-shore wind power plants, both from a levelized and marginal COE point of view.
Exergetic analysis of autonomous power complex for drilling rig
NASA Astrophysics Data System (ADS)
Lebedev, V. A.; Karabuta, V. S.
2017-10-01
The article considers the issue of increasing the energy efficiency of power equipment of the drilling rig. At present diverse types of power plants are used in power supply systems. When designing and choosing a power plant, one of the main criteria is its energy efficiency. The main indicator in this case is the effective efficiency factor calculated by the method of thermal balances. In the article, it is suggested to use the exergy method to determine energy efficiency, which allows to perform estimations of the thermodynamic perfection degree of the system by the example of a gas turbine plant: relative estimation (exergetic efficiency factor) and an absolute estimation. An exergetic analysis of the gas turbine plant operating in a simple scheme was carried out using the program WaterSteamPro. Exergy losses in equipment elements are calculated.
Energy Efficiency of Low-Temperature Deaeration of Makeup Water for a District Heating System
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sharapov, V. I., E-mail: vlad-sharapov2008@yandex.ru; Kudryavtseva, E. V.
2016-07-15
It is shown that the temperature of makeup water in district heating systems has a strong effect on the energy efficiency of turbines of thermal power plants. A low-temperature deaeration process that considerably improves the energy efficiency of thermal power plants is developed. The desorbing agent is the gas supplied to the burners of the boiler. The energy efficiency of the process for a typical unit of thermal power plant is assessed.
Thermodynamics Analysis of Binary Plant Generating Power from Low-Temperature Geothermal Resource
NASA Astrophysics Data System (ADS)
Maksuwan, A.
2018-05-01
The purpose in this research was to predict tendency of increase Carnot efficiency of the binary plant generating power from low-temperature geothermal resource. Low-temperature geothermal resources or less, are usually exploited by means of binary-type energy conversion systems. The maximum efficiency is analyzed for electricity production of the binary plant generating power from low-temperature geothermal resource becomes important. By using model of the heat exchanger equivalent to a power plant together with the calculation of the combined heat and power (CHP) generation. The CHP was solved in detail with appropriate boundary originating an idea from the effect of temperature of source fluid inlet-outlet and cooling fluid supply. The Carnot efficiency from the CHP calculation was compared between condition of increase temperature of source fluid inlet-outlet and decrease temperature of cooling fluid supply. Result in this research show that the Carnot efficiency for binary plant generating power from low-temperature geothermal resource has tendency increase by decrease temperature of cooling fluid supply.
NASA Astrophysics Data System (ADS)
Petrakopoulou, F.; Sanz, J.
2014-12-01
Steam electrolysis is a promising process of large-scale centralized hydrogen production, while it is also considered an excellent option for the efficient use of renewable solar and geothermal energy resources. This work studies the operation of an intermediate temperature steam electrolyzer (ITSE) and its incorporation into hybrid power plants that include biomass combustion and photovoltaic panels (PV). The plants generate both electricity and hydrogen. The reference -biomass- power plant and four variations of a hybrid biomass-PV incorporating the reference biomass plant and the ITSE are simulated and evaluated using exergetic analysis. The variations of the hybrid power plants are associated with (1) the air recirculation from the electrolyzer to the biomass power plant, (2) the elimination of the sweep gas of the electrolyzer, (3) the replacement of two electric heaters with gas/gas heat exchangers, and (4) the replacement two heat exchangers of the reference electrolyzer unit with one heat exchanger that uses steam from the biomass power plant. In all cases, 60% of the electricity required in the electrolyzer is covered by the biomass plant and 40% by the photovoltaic panels. When comparing the hybrid plants with the reference biomass power plant that has identical operation and structure as that incorporated in the hybrid plants, we observe an efficiency decrease that varies depending on the scenario. The efficiency decrease stems mainly from the low effectiveness of the photovoltaic panels (14.4%). When comparing the hybrid scenarios, we see that the elimination of the sweep gas decreases the power consumption due to the elimination of the compressor used to cover the pressure losses of the filter, the heat exchangers and the electrolyzer. Nevertheless, if the sweep gas is used to preheat the air entering the boiler of the biomass power plant, the efficiency of the plant increases. When replacing the electric heaters with gas-gas heat exchangers, the efficiency of the plant increases, although the higher pressure losses of the flue-gas path increase the requirements of the air compressor. Finally, replacing the two heat exchangers of the electrolyzer unit with one that uses extracted steam from the biomass power plant can lead to an overall decrease in the operating and investment costs of the plant.
Sourcing of Steam and Electricity for Carbon Capture Retrofits.
Supekar, Sarang D; Skerlos, Steven J
2017-11-07
This paper compares different steam and electricity sources for carbon capture and sequestration (CCS) retrofits of pulverized coal (PC) and natural gas combined cycle (NGCC) power plants. Analytical expressions for the thermal efficiency of these power plants are derived under 16 different CCS retrofit scenarios for the purpose of illustrating their environmental and economic characteristics. The scenarios emerge from combinations of steam and electricity sources, fuel used in each source, steam generation equipment and process details, and the extent of CO 2 capture. Comparing these scenarios reveals distinct trade-offs between thermal efficiency, net power output, levelized cost, profit, and net CO 2 reduction. Despite causing the highest loss in useful power output, bleeding steam and extracting electric power from the main power plant to meet the CCS plant's electricity and steam demand maximizes plant efficiency and profit while minimizing emissions and levelized cost when wholesale electricity prices are below 4.5 and 5.2 US¢/kWh for PC-CCS and NGCC-CCS plants, respectively. At prices higher than these higher profits for operating CCS retrofits can be obtained by meeting 100% of the CCS plant's electric power demand using an auxiliary natural gas turbine-based combined heat and power plant.
Study on key technologies of optimization of big data for thermal power plant performance
NASA Astrophysics Data System (ADS)
Mao, Mingyang; Xiao, Hong
2018-06-01
Thermal power generation accounts for 70% of China's power generation, the pollutants accounted for 40% of the same kind of emissions, thermal power efficiency optimization needs to monitor and understand the whole process of coal combustion and pollutant migration, power system performance data show explosive growth trend, The purpose is to study the integration of numerical simulation of big data technology, the development of thermal power plant efficiency data optimization platform and nitrogen oxide emission reduction system for the thermal power plant to improve efficiency, energy saving and emission reduction to provide reliable technical support. The method is big data technology represented by "multi-source heterogeneous data integration", "large data distributed storage" and "high-performance real-time and off-line computing", can greatly enhance the energy consumption capacity of thermal power plants and the level of intelligent decision-making, and then use the data mining algorithm to establish the boiler combustion mathematical model, mining power plant boiler efficiency data, combined with numerical simulation technology to find the boiler combustion and pollutant generation rules and combustion parameters of boiler combustion and pollutant generation Influence. The result is to optimize the boiler combustion parameters, which can achieve energy saving.
Closed Cycle Magnetohydrodynamic Nuclear Space Power Generation Using Helium/Xenon Working Plasma
NASA Technical Reports Server (NTRS)
Litchford, R. J.; Harada, N.
2005-01-01
A multimegawatt-class nuclear fission powered closed cycle magnetohydrodynamic space power plant using a helium/xenon working gas has been studied, to include a comprehensive system analysis. Total plant efficiency was expected to be 55.2 percent including pre-ionization power. The effects of compressor stage number, regenerator efficiency, and radiation cooler temperature on plant efficiency were investigated. The specific mass of the power generation plant was also examined. System specific mass was estimated to be 3 kg/kWe for a net electrical output power of 1 MWe, 2-3 kg/kWe at 2 MWe, and approx.2 kg/KWe at >3 MWe. Three phases of research and development plan were proposed: (1) Phase I-proof of principle, (2) Phase II-demonstration of power generation, and (3) Phase III-prototypical closed loop test.
Prospects for the development of coal-steam plants in Russia
NASA Astrophysics Data System (ADS)
Tumanovskii, A. G.
2017-06-01
Evaluation of the technical state of the modern coal-fired power plants and quality of coal consumed by Russian thermal power plants (TPP) is provided. Measures aimed at improving the economic and environmental performance of operating 150-800 MW coal power units are considered. Ways of efficient use of technical methods of NO x control and electrostatic precipitators' upgrade for improving the efficiency of ash trapping are summarized. Examples of turbine and boiler equipment efficiency upgrading through its deep modernization are presented. The necessity of the development and introduction of new technologies in the coal-fired power industry is shown. Basic technical requirements for a 660-800 MW power unit with the steam conditions of 28 MPa, 600/600°C are listed. Design solutions taking into account features of Russian coal combustion are considered. A field of application of circulating fluidized bed (CFB) boilers and their effectiveness are indicated. The results of development of a new generation coal-fired TPP, including a steam turbine with an increased efficiency of the compartments and disengaging clutch, an elevated steam conditions boiler, and a highly efficient NO x /SO2 and ash particles emission control system are provided. In this case, the resulting ash and slag are not to be sent to the ash dumps and are to be used to a maximum advantage. Technical solutions to improve the efficiency of coal gasification combined cycle plants (CCP) are considered. A trial plant based on a 16 MW gas turbine plant (GTP) and an air-blown gasifier is designed as a prototype of a high-power CCP. The necessity of a state-supported technical reequipment and development program of operating coal-fired power units, as well as putting into production of new generation coal-fired power plants, is noted.
Efficient and equitable spatial allocation of renewable power plants at the country scale
NASA Astrophysics Data System (ADS)
Drechsler, Martin; Egerer, Jonas; Lange, Martin; Masurowski, Frank; Meyerhoff, Jürgen; Oehlmann, Malte
2017-09-01
Globally, the production of renewable energy is undergoing rapid growth. One of the most pressing issues is the appropriate allocation of renewable power plants, as the question of where to produce renewable electricity is highly controversial. Here we explore this issue through analysis of the efficient and equitable spatial allocation of wind turbines and photovoltaic power plants in Germany. We combine multiple methods, including legal analysis, economic and energy modelling, monetary valuation and numerical optimization. We find that minimum distances between renewable power plants and human settlements should be as small as is legally possible. Even small reductions in efficiency lead to large increases in equity. By considering electricity grid expansion costs, we find a more even allocation of power plants across the country than is the case when grid expansion costs are neglected.
NASA Astrophysics Data System (ADS)
Gardiner, John Corby
The electric power industry market structure has changed over the last twenty years since the passage of the Public Utility Regulatory Policies Act (PURPA). These changes include the entry by unregulated generator plants and, more recently, the deregulation of entry and price in the retail generation market. Such changes have introduced and expanded competitive forces on the incumbent electric power plants. Proponents of this deregulation argued that the enhanced competition would lead to a more efficient allocation of resources. Previous studies of power plant technical and allocative efficiency have failed to measure technical and allocative efficiency at the plant level. In contrast, this study uses panel data on 35 power plants over 59 years to estimate technical and allocative efficiency of each plant. By using a flexible functional form, which is not constrained by the assumption that regulation is constant over the 59 years sampled, the estimation procedure accounts for changes in both state and national regulatory/energy policies that may have occurred over the sample period. The empirical evidence presented shows that most of the power plants examined have operated more efficiently since the passage of PURPA and the resultant increase of competitive forces. Chapter 2 extends the model used in Chapter 1 and clarifies some issues in the efficiency literature by addressing the case where homogeneity does not hold. A more general model is developed for estimating both input and output inefficiency simultaneously. This approach reveals more information about firm inefficiency than the single estimation approach that has previously been used in the literature. Using the more general model, estimates are provided on the type of inefficiency that occurs as well as the cost of inefficiency by type of inefficiency. In previous studies, the ranking of firms by inefficiency has been difficult because of the cardinal and ordinal differences between different types of inefficiency estimates. However, using the general approach, this study illustrates that plants can be ranked by overall efficiency.
Energy comparison between solar thermal power plant and photovoltaic power plant
NASA Astrophysics Data System (ADS)
Novosel, Urška; Avsec, Jurij
2017-07-01
The combined use of renewable energy and alternative energy systems and better efficiency of energy devices is a promising approach to reduce effects due to global warming in the world. On the basis of first and second law of thermodynamics we could optimize the processes in the energy sector. The presented paper shows the comparison between solar thermal power plant and photovoltaic power plant in terms of energy, exergy and life cycle analysis. Solar thermal power plant produces electricity with basic Rankine cycle, using solar tower and solar mirrors to produce high fluid temperature. Heat from the solar system is transferred by using a heat exchanger to Rankine cycle. Both power plants produce hydrogen via electrolysis. The paper shows the global efficiency of the system, regarding production of the energy system.
Grozdov, D S; Kolotov, V P; Lavrukhin, Yu E
2016-04-01
A method of full energy peak efficiency estimation in the space around scintillation detector, including the presence of a collimator, has been developed. It is based on a mathematical convolution of the experimental results with the following data extrapolation. The efficiency data showed the average uncertainty less than 10%. Software to calculate integral efficiency for nuclear power plant plume was elaborated. The paper also provides results of nuclear power plant plume height estimation by analysis of the spectral data. Copyright © 2016 Elsevier Ltd. All rights reserved.
Method of optimizing performance of Rankine cycle power plants
Pope, William L.; Pines, Howard S.; Doyle, Padraic A.; Silvester, Lenard F.
1982-01-01
A method for efficiently operating a Rankine cycle power plant (10) to maximize fuel utilization efficiency or energy conversion efficiency or minimize costs by selecting a turbine (22) fluid inlet state which is substantially in the area adjacent and including the transposed critical temperature line (46).
NASA Technical Reports Server (NTRS)
Corman, J. C.
1976-01-01
A data base for the comparison of advanced energy conversion systems for utility applications using coal or coal-derived fuels was developed. Estimates of power plant performance (efficiency), capital cost, cost of electricity, natural resource requirements, and environmental intrusion characteristics were made for ten advanced conversion systems. Emphasis was on the energy conversion system in the context of a base loaded utility power plant. All power plant concepts were premised on meeting emission standard requirements. A steam power plant (3500 psig, 1000 F) with a conventional coal-burning furnace-boiler was analyzed as a basis for comparison. Combined cycle gas/steam turbine system results indicated competitive efficiency and a lower cost of electricity compared to the reference steam plant. The Open-Cycle MHD system results indicated the potential for significantly higher efficiency than the reference steam plant but with a higher cost of electricity.
Method of optimizing performance of Rankine cycle power plants. [US DOE Patent
Pope, W.L.; Pines, H.S.; Doyle, P.A.; Silvester, L.F.
1980-06-23
A method is described for efficiently operating a Rankine cycle power plant to maximize fuel utilization efficiency or energy conversion efficiency or minimize costs by selecting a turbine fluid inlet state which is substantially on the area adjacent and including the transposed critical temperature line.
Performance calculations for 200-1000 MWe MHD/steam power plants
NASA Technical Reports Server (NTRS)
Staiger, P. J.
1981-01-01
The effects of MHD generator length, level of oxygen enrichment, and oxygen production power on the performance of MHD/steam power plants ranging from 200 to 1000 MW in electrical output are investigated. The plants considered use oxygen enriched combustion air preheated to 1100 F. Both plants in which the MHD generator is cooled with low temperature and pressure boiler feedwater and plants in which the generator is cooled with high temperature and pressure boiler feedwater are considered. For plants using low temperature boiler feedwater for generator cooling the maximum thermodynamic efficiency is obtained with shorter generators and a lower level of oxygen enrichment compared to plants using high temperature boiler feedwater for generator cooling. The generator length at which the maximum plant efficiency occurs increases with power plant size for plants with a generator cooled by low temperature feedwater. Also shown is the relationship of the magnet stored energy requirement of the generator length and the power plant performance. Possible cost/performance tradeoffs between magnet cost and plant performance are indicated.
NASA Astrophysics Data System (ADS)
Campanari, Stefano; Mastropasqua, Luca; Gazzani, Matteo; Chiesa, Paolo; Romano, Matteo C.
2016-08-01
Driven by the search for the highest theoretical efficiency, in the latest years several studies investigated the integration of high temperature fuel cells in natural gas fired power plants, where fuel cells are integrated with simple or modified Brayton cycles and/or with additional bottoming cycles, and CO2 can be separated via chemical or physical separation, oxy-combustion and cryogenic methods. Focusing on Solid Oxide Fuel Cells (SOFC) and following a comprehensive review and analysis of possible plant configurations, this work investigates their theoretical potential efficiency and proposes two ultra-high efficiency plant configurations based on advanced intermediate-temperature SOFCs integrated with a steam turbine or gas turbine cycle. The SOFC works at atmospheric or pressurized conditions and the resulting power plant exceeds 78% LHV efficiency without CO2 capture (as discussed in part A of the work) and 70% LHV efficiency with substantial CO2 capture (part B). The power plants are simulated at the 100 MW scale with a complete set of realistic assumptions about fuel cell (FC) performance, plant components and auxiliaries, presenting detailed energy and material balances together with a second law analysis.
Statistical modeling of an integrated boiler for coal fired thermal power plant.
Chandrasekharan, Sreepradha; Panda, Rames Chandra; Swaminathan, Bhuvaneswari Natrajan
2017-06-01
The coal fired thermal power plants plays major role in the power production in the world as they are available in abundance. Many of the existing power plants are based on the subcritical technology which can produce power with the efficiency of around 33%. But the newer plants are built on either supercritical or ultra-supercritical technology whose efficiency can be up to 50%. Main objective of the work is to enhance the efficiency of the existing subcritical power plants to compensate for the increasing demand. For achieving the objective, the statistical modeling of the boiler units such as economizer, drum and the superheater are initially carried out. The effectiveness of the developed models is tested using analysis methods like R 2 analysis and ANOVA (Analysis of Variance). The dependability of the process variable (temperature) on different manipulated variables is analyzed in the paper. Validations of the model are provided with their error analysis. Response surface methodology (RSM) supported by DOE (design of experiments) are implemented to optimize the operating parameters. Individual models along with the integrated model are used to study and design the predictive control of the coal-fired thermal power plant.
NASA Astrophysics Data System (ADS)
Pham, John Dinh Chuong
In the twenty first century, global warming and climate change have become environmental issues worldwide. There is a need to reduce greenhouse gas emissions from thermal power plants through improved efficiency. This need is shared by both developed and developing countries. It is particularly important in rapidly developing economies (for example, Vietnam, South Korea, and China) where there is very significant need to increase generation capacity. This thesis addresses improving thermal power plant efficiency through an improved planning process that emphasizes integrated design. With the integration of planning and design considerations of key components in thermal electrical generation, along with the selection of appropriate up-to-date technologies, greater efficiency and reduction of emissions could be achieved. The major barriers to the integration of overall power plant optimization are the practice of individual island tendering packages, and the lack of coordinating efforts between major original equipment manufacturers (OEM). This thesis assesses both operational and design aspects of thermal power plants to identify opportunities for energy saving and the associated reduction of CO2 emissions. To demonstrate the potential of the integrated planning design approach, three advanced thermal power plants, using anthracite coal, oil and gas as their respective fuel, were developed as a case study. The three plant formulations and simulations were performed with the cooperation of several leading companies in the power industry including Babcock & Wilcox, Siemens KWU, Siemens-Westinghouse Power Corporation, Hitachi, Alstom Air Preheater, TLT-Covent, and ABB Flakt. The first plant is a conventional W-Flame anthracite coal-fired unit for base load operation. The second is a supercritical oil-fired plant with advanced steam condition, for two shifting and cycling operations. The third plant is a gas-fired combined cycle unit employing a modern steam-cooled gas turbine and a three-pressure heat recovery steam generator with reheat, for base load and load following operations. The oil-fired and gas-fired plants showed excellent gross thermal efficiency, 49.6 and 59.4 percent, respectively. Regarding the anthracite plant, based on a traditional subcritical pressure steam cycle, the unit gross efficiency was calculated at 42.3 percent. These efficiency values represent an increase of over 2 percent compared to the comparable plant class, operating today. This 2 percent efficiency gained translates into approximately 35,000 tonnes of greenhouse gas reduction, and a saving of 16,000 tonnes of coal, per year (based on 300MWe coal-fired plant). The positive results from the three simulations have demonstrated that by integrating planning and design optimization, significant gain of efficiency in thermal power plants is possible. This establishes the need for improved planning processes. It starts with a pre-planning process, before project tendering, to identify applicable operational issues and design features to enhance efficiency and reduce emissions. It should also include a pre-contract period to provide an opportunity for all OEM finalists to consolidate and fine-tune their designs for compatibility with those of others to achieve optimal performance. The inclusion of a period for final consolidation and integrated design enables the original goals of greater overall plant efficiency and greenhouse gas emissions reduction to be achieved beyond those available from current planning and contracting procedures.
Review of the coal-fired, over-supercritical and ultra-supercritical steam power plants
NASA Astrophysics Data System (ADS)
Tumanovskii, A. G.; Shvarts, A. L.; Somova, E. V.; Verbovetskii, E. Kh.; Avrutskii, G. D.; Ermakova, S. V.; Kalugin, R. N.; Lazarev, M. V.
2017-02-01
The article presents a review of developments of modern high-capacity coal-fired over-supercritical (OSC) and ultra-supercritical (USC) steam power plants and their implementation. The basic engineering solutions are reported that ensure the reliability, economic performance, and low atmospheric pollution levels. The net efficiency of the power plants is increased by optimizing the heat balance, improving the primary and auxiliary equipment, and, which is the main thing, by increasing the throttle conditions. As a result of the enhanced efficiency, emissions of hazardous substances into the atmosphere, including carbon dioxide, the "greenhouse" gas, are reduced. To date, the exhaust steam conditions in the world power industry are p 0 ≈ 30 MPa and t 0 = 610/620°C. The efficiency of such power plants reaches 47%. The OSC plants are being operated in Germany, Denmark, Japan, China, and Korea; pilot plants are being developed in Russia. Currently, a project of a power plant for the ultra-supercritical steam conditions p 0 ≈ 35 MPa and t 0 = 700/720°C with efficiency of approximately 50% is being studied in the EU within the framework of the Thermie AD700 program, project AD 700PF. Investigations in this field have also been launched in the United States, Japan, and China. Engineering solutions are also being sought in Russia by the All-Russia Thermal Engineering Research Institute (VTI) and the Moscow Power Engineering Institute. The stated steam parameter level necessitates application of new materials, namely, nickel-base alloys. Taking into consideration high costs of nickel-base alloys and the absence in Russia of technologies for their production and manufacture of products from these materials for steam-turbine power plants, the development of power plants for steam parameters of 32 MPa and 650/650°C should be considered to be the first stage in creating the USC plants as, to achieve the above parameters, no expensive alloys are require. To develop and construct OSC and USC head power plants, joint efforts of the government, experts in power industry and metallurgy, scientific institutions, and equipment manufacturers are required.
Compressed Natural Gas Technology for Alternative Fuel Power Plants
NASA Astrophysics Data System (ADS)
Pujotomo, Isworo
2018-02-01
Gas has great potential to be converted into electrical energy. Indonesia has natural gas reserves up to 50 years in the future, but the optimization of the gas to be converted into electricity is low and unable to compete with coal. Gas is converted into electricity has low electrical efficiency (25%), and the raw materials are more expensive than coal. Steam from a lot of wasted gas turbine, thus the need for utilizing exhaust gas results from gas turbine units. Combined cycle technology (Gas and Steam Power Plant) be a solution to improve the efficiency of electricity. Among other Thermal Units, Steam Power Plant (Combined Cycle Power Plant) has a high electrical efficiency (45%). Weakness of the current Gas and Steam Power Plant peak burden still using fuel oil. Compressed Natural Gas (CNG) Technology may be used to accommodate the gas with little land use. CNG gas stored in the circumstances of great pressure up to 250 bar, in contrast to gas directly converted into electricity in a power plant only 27 bar pressure. Stored in CNG gas used as a fuel to replace load bearing peak. Lawyer System on CNG conversion as well as the power plant is generally only used compressed gas with greater pressure and a bit of land.
Choice of optimal working fluid for binary power plants at extremely low temperature brine
NASA Astrophysics Data System (ADS)
Tomarov, G. V.; Shipkov, A. A.; Sorokina, E. V.
2016-12-01
The geothermal energy development problems based on using binary power plants utilizing lowpotential geothermal resources are considered. It is shown that one of the possible ways of increasing the efficiency of heat utilization of geothermal brine in a wide temperature range is the use of multistage power systems with series-connected binary power plants based on incremental primary energy conversion. Some practically significant results of design-analytical investigations of physicochemical properties of various organic substances and their influence on the main parameters of the flowsheet and the technical and operational characteristics of heat-mechanical and heat-exchange equipment for binary power plant operating on extremely-low temperature geothermal brine (70°C) are presented. The calculation results of geothermal brine specific flow rate, capacity (net), and other operation characteristics of binary power plants with the capacity of 2.5 MW at using various organic substances are a practical interest. It is shown that the working fluid selection significantly influences on the parameters of the flowsheet and the operational characteristics of the binary power plant, and the problem of selection of working fluid is in the search for compromise based on the priorities in the field of efficiency, safety, and ecology criteria of a binary power plant. It is proposed in the investigations on the working fluid selection of the binary plant to use the plotting method of multiaxis complex diagrams of relative parameters and characteristic of binary power plants. Some examples of plotting and analyzing these diagrams intended to choose the working fluid provided that the efficiency of geothermal brine is taken as main priority.
NASA Astrophysics Data System (ADS)
Dreißigacker, Volker
2018-04-01
The development of new technologies for large-scale electricity storage is a key element in future flexible electricity transmission systems. Electricity storage in adiabatic compressed air energy storage (A-CAES) power plants offers the prospect of making a substantial contribution to reach this goal. This concept allows efficient, local zero-emission electricity storage on the basis of compressed air in underground caverns. The compression and expansion of air in turbomachinery help to balance power generation peaks that are not demand-driven on the one hand and consumption-induced load peaks on the other. For further improvements in cost efficiencies and flexibility, system modifications are necessary. Therefore, a novel concept regarding the integration of an electrical heating component is investigated. This modification allows increased power plant flexibilities and decreasing component sizes due to the generated high temperature heat with simultaneously decreasing total round trip efficiencies. For an exemplarily A-CAES case simulation studies regarding the electrical heating power and thermal energy storage sizes were conducted to identify the potentials in cost reduction of the central power plant components and the loss in round trip efficiency.
A new framework to increase the efficiency of large-scale solar power plants.
NASA Astrophysics Data System (ADS)
Alimohammadi, Shahrouz; Kleissl, Jan P.
2015-11-01
A new framework to estimate the spatio-temporal behavior of solar power is introduced, which predicts the statistical behavior of power output at utility scale Photo-Voltaic (PV) power plants. The framework is based on spatio-temporal Gaussian Processes Regression (Kriging) models, which incorporates satellite data with the UCSD version of the Weather and Research Forecasting model. This framework is designed to improve the efficiency of the large-scale solar power plants. The results are also validated from measurements of the local pyranometer sensors, and some improvements in different scenarios are observed. Solar energy.
Simulation of hybrid solar power plants
NASA Astrophysics Data System (ADS)
Dieckmann, Simon; Dersch, Jürgen
2017-06-01
Hybrid solar power plants have the potential to combine advantages of two different technologies at the cost of increased complexity. The present paper shows the potential of the software greenius for the techno-economic evaluation of hybrid solar power plants and discusses two exemplary scenarios. Depreciated Concentrated Solar Power (CSP) plants based on trough technology can be retrofitted with solar towers in order to reach higher steam cycle temperatures and hence efficiencies. Compared to a newly built tower plant the hybridization of a depreciated trough plant causes about 30% lower LCOE reaching 104 /MWh. The second hybrid scenario combines cost-efficient photovoltaics with dispatchable CSP technology. This hybrid plant offers very high capacity factors up to 69% based on 100% load from 8am to 11pm. The LCOE of the hybrid plant are only slightly lower (174 vs. 186 /MWh) compared to the pure CSP plant because the capital expenditure for thermal storage and power block remains the same while the electricity output is much lower.
Agamy, Mohammed; Elasser, Ahmed; Sabate, Juan Antonio; Galbraith, Anthony William; Harfman Todorovic, Maja
2014-09-09
A distributed photovoltaic (PV) power plant includes a plurality of distributed dc-dc converters. The dc-dc converters are configured to switch in coordination with one another such that at least one dc-dc converter transfers power to a common dc-bus based upon the total system power available from one or more corresponding strings of PV modules. Due to the coordinated switching of the dc-dc converters, each dc-dc converter transferring power to the common dc-bus continues to operate within its optimal efficiency range as well as to optimize the maximum power point tracking in order to increase the energy yield of the PV power plant.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Michael G. McKellar; Edwin A. Harvego; Anastasia A. Gandrik
2010-10-01
A design for a commercial-scale high-temperature electrolysis (HTE) plant for hydrogen production has been developed. The HTE plant is powered by a high-temperature gas-cooled reactor (HTGR) whose configuration and operating conditions are based on the latest design parameters planned for the Next Generation Nuclear Plant (NGNP). The current HTGR reference design specifies a reactor power of 600 MWt, with a primary system pressure of 7.0 MPa, and reactor inlet and outlet fluid temperatures of 322°C and 750°C, respectively. The power conversion unit will be a Rankine steam cycle with a power conversion efficiency of 40%. The reference hydrogen production plantmore » operates at a system pressure of 5.0 MPa, and utilizes a steam-sweep system to remove the excess oxygen that is evolved on the anode (oxygen) side of the electrolyzer. The overall system thermal-to-hydrogen production efficiency (based on the higher heating value of the produced hydrogen) is 40.4% at a hydrogen production rate of 1.75 kg/s and an oxygen production rate of 13.8 kg/s. An economic analysis of this plant was performed with realistic financial and cost estimating assumptions. The results of the economic analysis demonstrated that the HTE hydrogen production plant driven by a high-temperature helium-cooled nuclear power plant can deliver hydrogen at a cost of $3.67/kg of hydrogen assuming an internal rate of return, IRR, of 12% and a debt to equity ratio of 80%/20%. A second analysis shows that if the power cycle efficiency increases to 44.4%, the hydrogen production efficiency increases to 42.8% and the hydrogen and oxygen production rates are 1.85 kg/s and 14.6 kg/s respectively. At the higher power cycle efficiency and an IRR of 12% the cost of hydrogen production is $3.50/kg.« less
Advanced coal gasifier-fuel cell power plant systems design
NASA Technical Reports Server (NTRS)
Heller, M. E.
1983-01-01
Two advanced, high efficiency coal-fired power plants were designed, one utilizing a phosphoric acid fuel cell and one utilizing a molten carbonate fuel cell. Both incorporate a TRW Catalytic Hydrogen Process gasifier and regenerator. Both plants operate without an oxygen plant and without requiring water feed; they, instead, require makeup dolomite. Neither plant requires a shift converter; neither plant has heat exchangers operating above 1250 F. Both plants have attractive efficiencies and costs. While the molten carbonate version has a higher (52%) efficiency than the phosphoric acid version (48%), it also has a higher ($0.078/kWh versus $0.072/kWh) ten-year levelized cost of electricity. The phosphoric acid fuel cell power plant is probably feasible to build in the near term: questions about the TRW process need to be answered experimentally, such as weather it can operate on caking coals, and how effective the catalyzed carbon-dioxide acceptor will be at pilot scale, both in removing carbon dioxide and in removing sulfur from the gasifier.
Efficient electrochemical refrigeration power plant using natural gas with ∼100% CO2 capture
NASA Astrophysics Data System (ADS)
Al-musleh, Easa I.; Mallapragada, Dharik S.; Agrawal, Rakesh
2015-01-01
We propose an efficient Natural Gas (NG) based Solid Oxide Fuel Cell (SOFC) power plant equipped with ∼100% CO2 capture. The power plant uses a unique refrigeration based process to capture and liquefy CO2 from the SOFC exhaust. The capture of CO2 is carried out via condensation and purification using two rectifying columns operating at different pressures. The uncondensed gas mixture, comprising of relatively high purity unconverted fuel, is recycled to the SOFC and found to boost the power generation of the SOFC by 22%, when compared to a stand alone SOFC. If Liquefied Natural Gas (LNG) is available at the plant gate, then the refrigeration available from its evaporation is used for CO2 Capture and Liquefaction (CO2CL). If NG is utilized, then a Mixed Refrigerant (MR) vapor compression cycle is utilized for CO2CL. Alternatively, the necessary refrigeration can be supplied by evaporating the captured liquid CO2 at a lower pressure, which is then compressed to supercritical pressures for pipeline transportation. From rigorous simulations, the power generation efficiency of the proposed processes is found to be 70-76% based on lower heating value (LHV). The benefit of the proposed processes is evident when the efficiency of 73% for a conventional SOFC-Gas turbine power plant without CO2 capture is compared with an equivalent efficiency of 71.2% for the proposed process with CO2CL.
This EPA-led project, conducted in collaboration with UNEP, the Swedish Environmental Institute and various Russian Institutes, that demonstrates that the mercury emission control efficiencies of activated carbon injection technologies applied at a Russian power plant burning Rus...
Coal-Fired Power Plant Heat Rate Reductions
View a report that identifies systems and equipment in coal-fired power plants where efficiency improvements can be realized, and provides estimates of the resulting net plant heat rate reductions and costs for implementation.
Coal-Powered Electric Generating Unit Efficiency and Reliability Dialogue: Summary Report
DOE Office of Scientific and Technical Information (OSTI.GOV)
Taylor, Emmanuel
Coal continues to play a critical role in powering the Nation’s electricity generation, especially for baseload power plants. With aging coal generation assets facing decreased performance due to the state of the equipment, and with challenges exacerbated by the current market pressures on the coal sector, there are opportunities to advance early-stage technologies that can retrofit or replace equipment components. These changes will eventually result in significant improvements in plant performance once further developed and deployed by industry. Research and development in areas such as materials, fluid dynamics, fuel properties and preparation characteristics, and a new generation of plant controlsmore » can lead to new components and systems that can help improve the efficiency and reliability of coal-fired power plants significantly, allowing these assets to continue to provide baseload power. Coal stockpiles at electricity generation plants are typically large enough to provide 30 to 60 days of power prior to resupply—significantly enhancing the stability and reliability of the U.S. electricity sector. Falling prices for non-dispatchable renewable energy and mounting environmental regulations, among other factors, have stimulated efforts to improve the efficiency of these coal-fired electric generating units (EGUs). In addition, increased reliance on natural gas and non-dispatchable energy sources has spurred efforts to further increase the reliability of coal EGUs. The Coal Powered EGU Efficiency and Reliability Dialogue brought together stakeholders from across the coal EGU industry to discuss methods for improvement. Participants at the event reviewed performance-enhancing innovations in coal EGUs, discussed the potential for data-driven management practices to increase efficiency and reliability, investigated the impacts of regulatory compliance on coal EGU performance, and discussed upcoming challenges for the coal industry. This report documents the key findings and research suggestions discussed at the event. Discussions at the workshop will aid DOE in developing a set of distinct initiatives that can be pursued by government and industry to realize promising technological pursuits. DOE plans to use the results of the Dialogue coupled with ongoing technical analysis of efficiency opportunities within the coal-fired fleet, and additional studies to develop a comprehensive strategy for capitalizing on thermal efficiency improvements. Expected Power Plant Efficiency Improvements include developing cost-effective, efficient, and reliable technologies for boilers, turbines, and sensors and controls to improve the reliability and efficiency of existing coal-based power plants. The Office of Fossil Energy at DOE plans to work with industry to develop knowledge pertaining to advanced technologies and systems that industry can subsequently develop. These technologies and systems will increase reliability, add operational flexibility and improve efficiency, thereby providing more robust power generation infrastructure. The following table lists the research suggestions and questions for further investigation that were identified by participants in each session of the dialogue.« less
Parametric study of potential early commercial MHD power plants
NASA Technical Reports Server (NTRS)
Hals, F. A.
1979-01-01
Three different reference power plant configurations were considered with parametric variations of the various design parameters for each plant. Two of the reference plant designs were based on the use of high temperature regenerative air preheaters separately fired by a low Btu gas produced from a coal gasifier which was integrated with the power plant. The third reference plant design was based on the use of oxygen enriched combustion air preheated to a more moderate temperature in a tubular type metallic recuperative heat exchanger which is part of the bottoming plant heat recovery system. Comparative information was developed on plant performance and economics. The highest net plant efficiency of about 45 percent was attained by the reference plant design with the use of a high temperature air preheater separately fired with the advanced entrained bed gasifier. The use of oxygen enrichment of the combustion air yielded the lowest cost of generating electricity at a slightly lower plant efficiency. Both of these two reference plant designs are identified as potentially attractive for early MHD power plant applications.
Thermal and nuclear power plants: Competitiveness in the new economic conditions
NASA Astrophysics Data System (ADS)
Aminov, R. Z.; Shkret, A. F.; Garievskii, M. V.
2017-05-01
In recent years, the conditions of development and functionality of power generating assets have notably changed. Considering the decline in the price of hydrocarbon fuel on the global market, the efficiency of combined-cycle gas-turbine plants in the European part of Russia is growing in comparison with nuclear power plants. Capital investments in the construction of nuclear power plants have also increased as a result of stiffening the safety requirements. In view of this, there has been an increasing interest in exploration of effective lines of development of generating assets in the European part of Russia, taking consideration of the conditions that may arise in the nearest long-term perspective. In particular, the assessment of comparative efficiency of developing combined-cycle gas-turbine plants (operating on natural gas) in the European part of Russia and nuclear power plants is of academic and practical interest. In this article, we analyze the trends of changes in the regional price of hydrocarbon fuel. Using the prognosis of net-weighted import prices of natural gas in Western European countries—prepared by the International Energy Agency (IEA) and the Energy Research Institute of the Russian Academy of Sciences (ERIRAS)—the prices of natural gas in the European part of Russia equilibrated with import prices of this heat carrier in Western Europe were determined. The methodology of determining the comparative efficiency of combined-cycle gas turbine plants (CCGT) and nuclear power plants (NPP) were described; based on this, the possible development of basic CCGTs and NPPs with regard to the European part of Russia for various scenarios in the prognosis of prices of gaseous fuel in a broad range of change of specific investments in the given generating sources were assessed, and the extents of their comparative efficiency were shown. It was proven that, at specific investments in the construction of new NPPs in the amount of 5000 dollars/kW, nuclear power plants in the European part of Russia become less efficient as compared to CCGTs operating on natural gas.
NASA Astrophysics Data System (ADS)
Zhang, Li; Zhang, Yu; Zhou, Liansheng; E, Zhijun; Wang, Kun; Wang, Ziyue; Li, Guohao; Qu, Bin
2018-02-01
The waste heat energy efficiency for absorption heat pump recycling thermal power plant circulating water has been analyzed. After the operation of heat pump, the influences on power generation and heat generation of unit were taken into account. In the light of the characteristics of heat pump in different operation stages, the energy efficiency of heat pump was evaluated comprehensively on both sides of benefits belonging to electricity and benefits belonging to heat, which adopted the method of contrast test. Thus, the reference of energy efficiency for same type projects was provided.
NOVEL MERCURY OXIDANT AND SORBENT FOR MERCURY EMISSIONS CONTROL FROM COAL-FIRED POWER PLANTS
The authors have successfully developed novel efficient and cost-effective sorbent and oxidant for removing mercury from power plant flue gases. These sorbent and oxidant offer great promise for controlling mercury emissions from coal-fired power plants burning a wide range of c...
Demand of the power industry of Russia for gas turbines: the current state and prospects
NASA Astrophysics Data System (ADS)
Filippov, S. P.; Dil'man, M. D.; Ionov, M. S.
2017-11-01
The use of gas-turbine plants (GTPs) in the power industry of Russia is analyzed. Attention is paid to microturbines and low-, medium-, high-, and superhigh-power GTPs. The efficiency of the gas-turbine plants of domestic and foreign manufacture is compared. The actual values of the installed capacity utilization factor and the corresponding efficiency values are calculated for most GTPs operating in the country. The long-term demand of the country's electric power industry for GTPs for the period until 2040 is determined. The estimates have been obtained for three basic applications of the gas turbines, viz., for replacement of the GTPs that have exhausted their lifetime, replacement of outdated gas-turbine plants at gas-and-oilburning power plants, and construction of new thermal power plants to cover the anticipated growing demand for electric power. According to the findings of the research, the main item in the structure of the demand for GTPs will be their use to replace the decommissioned steam-turbine plants, predominantly those integrated into combined-cycle plants. The priority of the reconstruction of the thermal power plants in operation over the construction of new ones is determined by the large excess of accumulated installed capacities in the country and considerable savings on capital costs using production sites with completed infrastructure. It is established that medium- and high-power GTPs will be the most in-demand plants in the electric power industry. The demand for low-power GTPs will increase at high rates. The demand for microturbines is expected to be rather great. The demand for superhigh-power plants will become quantitatively significant after 2025 and grow rapidly afterwards. The necessity of accelerated development of competitive domestic GTPs with a wide range of capacities and mastering of their series manufacture as well as production of licensed gas turbines at a high production localization level on the territory of the country is shown. Considerable home demand for the power-generating GTPs and vast external markets will make the development of efficient domestic GTPs economically viable.
NASA Technical Reports Server (NTRS)
Amos, D. J.; Fentress, W. K.; Stahl, W. F.
1976-01-01
Both recuperated and bottomed closed cycle gas turbine systems in electric power plants were studied. All systems used a pressurizing gas turbine coupled with a pressurized furnace to heat the helium for the closed cycle gas turbine. Steam and organic vapors are used as Rankine bottoming fluids. Although plant efficiencies of over 40% are calculated for some plants, the resultant cost of electricity was found to be 8.75 mills/MJ (31.5 mills/kWh). These plants do not appear practical for coal or oil fired plants.
Gas core reactors for actinide transmutation and breeder applications
NASA Technical Reports Server (NTRS)
Clement, J. D.; Rust, J. H.
1978-01-01
This work consists of design power plant studies for four types of reactor systems: uranium plasma core breeder, uranium plasma core actinide transmuter, UF6 breeder and UF6 actinide transmuter. The plasma core systems can be coupled to MHD generators to obtain high efficiency electrical power generation. A 1074 MWt UF6 breeder reactor was designed with a breeding ratio of 1.002 to guard against diversion of fuel. Using molten salt technology and a superheated steam cycle, an efficiency of 39.2% was obtained for the plant and the U233 inventory in the core and heat exchangers was limited to 105 Kg. It was found that the UF6 reactor can produce high fluxes (10 to the 14th power n/sq cm-sec) necessary for efficient burnup of actinide. However, the buildup of fissile isotopes posed severe heat transfer problems. Therefore, the flux in the actinide region must be decreased with time. Consequently, only beginning-of-life conditions were considered for the power plant design. A 577 MWt UF6 actinide transmutation reactor power plant was designed to operate with 39.3% efficiency and 102 Kg of U233 in the core and heat exchanger for beginning-of-life conditions.
Second law analysis of advanced power generation systems using variable temperature heat sources
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bliem, C.J.; Mines, G.L.
1990-01-01
Many systems produce power using variable temperature (sensible) heat sources. The Heat Cycle Research Program is currently investigating the potential improvements to such power cycles utilizing moderate temperature geothermal resources to produce electrical power. It has been shown that mixtures of saturated hydrocarbons (alkanes) or halogenated hydrocarbons operating with a supercritical Rankine cycle gave improved performance over boiling Rankine cycles with the pure working fluids for typical applications. Recently, in addition to the supercritical Rankine Cycle, other types of cycles have been proposed for binary geothermal service. This paper explores the limits on efficiency of a feasible plant and discussesmore » the methods used in these advanced concept plants to achieve the maximum possible efficiency. The advanced plants considered appear to be approaching the feasible limit of performance so that the designer must weigh all considerations to fine the best plant for a given service. These results would apply to power systems in other services as well as to geothermal power plants. 17 refs., 15 figs.« less
Layouts of trigeneration plants for centralized power supply
NASA Astrophysics Data System (ADS)
Klimenko, A. V.; Agababov, V. S.; Il'ina, I. P.; Rozhnatovskii, V. D.; Burmakina, A. V.
2016-06-01
One of the possible and, under certain conditions, sufficiently effective methods for reducing consumption of fuel and energy resources is the development of plants for combined generation of different kinds of energy. In the power industry of Russia, the facilities have become widespread in which the cogeneration technology, i.e., simultaneous generation of electric energy and heat, is implemented. Such facilities can use different plants, viz., gas- and steam-turbine plants and gas-reciprocating units. Cogeneration power supply can be further developed by simultaneously supplying the users not only with electricity and heat but also with cold. Such a technology is referred to as trigeneration. To produce electricity and heat, trigeneration plants can use the same facilities that are used in cogeneration, namely, gas-turbine plants, steam-turbine plants, and gas-reciprocating units. Cold can be produced in trigeneration plants using thermotransformers of various kinds, such as vaporcompression thermotransformers, air thermotransformers, and absorption thermotransformers, that operate as chilling machines. The thermotransformers can also be used in the trigeneration plants to generate heat. The main advantage of trigeneration plants based on gas-turbine plants or gas-reciprocating units over cogeneration plants is the increased thermodynamic power supply efficiency owing to utilization of the waste-gas heat not only in winter but also in summer. In the steam-turbine-based trigeneration plants equipped with absorption thermotransformers, the enhancement of the thermodynamic power supply efficiency is determined by the increase in the heat extraction load during the nonheating season. The article presents calculated results that demonstrate higher thermodynamic efficiency of a gas-turbine-based plant with an absorption thermotransformer that operates in the trigeneration mode compared with a cogeneration gas-turbine plant. The structural arrangements of trigeneration plants designed to supply electricity, heat, and cold to the users are shown and the principles of their operation are described. The article presents results of qualitative analysis of different engineering solutions applied to select one combination of power- and heat-generating equipment and thermotransformers or another.
A dynamic model to assess tradeoffs in power production and riverine ecosystem protection.
Miara, Ariel; Vörösmarty, Charles J
2013-06-01
Major strategic planning decisions loom as society aims to balance energy security, economic development and environmental protection. To achieve such balance, decisions involving the so-called water-energy nexus must necessarily embrace a regional multi-power plant perspective. We present here the Thermoelectric Power & Thermal Pollution Model (TP2M), a simulation model that simultaneously quantifies thermal pollution of rivers and estimates efficiency losses in electricity generation as a result of fluctuating intake temperatures and river flows typically encountered across the temperate zone. We demonstrate the model's theoretical framework by carrying out sensitivity tests based on energy, physical and environmental settings. We simulate a series of five thermoelectric plants aligned along a hypothetical river, where we find that warm ambient temperatures, acting both as a physical constraint and as a trigger for regulatory limits on plant operations directly reduce electricity generation. As expected, environmental regulation aimed at reducing thermal loads at a single plant reduces power production at that plant, but ironically can improve the net electricity output from multiple plants when they are optimally co-managed. On the technology management side, high efficiency can be achieved through the use of natural gas combined cycle plants, which can raise the overall efficiency of the aging population of plants, including that of coal. Tradeoff analysis clearly shows the benefit of attaining such high efficiencies, in terms of both limiting thermal loads that preserve ecosystem services and increasing electricity production that benefits economic development.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Fathi, Nima; McDaniel, Patrick; Vorobieff, Peter
The aim of this paper is evaluating the efficiency of a novel combined solar-nuclear cycle. CFD-Thermal analysis is performed to apply the available surplus heat from the nuclear cycle and measure the available kinetic energy of air for the turbine of a solar chimney power plant system (SCPPS). The presented idea helps to decrease the thermal pollution and handle the water shortage supply for water plant by replacing the cooling tower by solar chimney power plant to get the surplus heat from the available warm air in the secondary loop of the reactor. By applying this idea to a typicalmore » 1000 MW nuclear power plant with a 0.33 thermal efficiency, we can increase it to 0.39.« less
NASA Technical Reports Server (NTRS)
Hals, F.; Kessler, R.; Swallom, D.; Westra, L.; Zar, J.; Morgan, W.; Bozzuto, C.
1980-01-01
The study deals with different 'moderate technology' entry-level commercial MHD power plants. Two of the reference plants are based on combustion of coal with air preheated in a high-temperature regenerative air heater separately fired with a low-BTU gas produced in a gasifier integrated with the power plant. The third reference plant design is based on the use of oxygen enriched combustion air. Performance calculations show that an overall power plant efficiency of the order of 44% can be reached with the use of oxygen enrichment.
Exploratory study of several advanced nuclear-MHD power plant systems.
NASA Technical Reports Server (NTRS)
Williams, J. R.; Clement, J. D.; Rosa, R. J.; Yang, Y. Y.
1973-01-01
In order for efficient multimegawatt closed cycle nuclear-MHD systems to become practical, long-life gas cooled reactors with exit temperatures of about 2500 K or higher must be developed. Four types of nuclear reactors which have the potential of achieving this goal are the NERVA-type solid core reactor, the colloid core (rotating fluidized bed) reactor, the 'light bulb' gas core reactor, and the 'coaxial flow' gas core reactor. Research programs aimed at developing these reactors have progressed rapidly in recent years so that prototype power reactors could be operating by 1980. Three types of power plant systems which use these reactors have been analyzed to determine the operating characteristics, critical parameters and performance of these power plants. Overall thermal efficiencies as high as 80% are projected, using an MHD turbine-compressor cycle with steam bottoming, and slightly lower efficiencies are projected for an MHD motor-compressor cycle.
JPRS Report, Science & Technology China: Energy
1992-10-26
The Xiaolongtan power plant is located at the Xiaolongtan open-cut coal mine and uses its coal directly from the conveyer belt. The first...which has resulted in high coal consumption, large power use by the plants, and low full-staff labor productivity and economic results. Examine coal ...consuming an additional 70 million tons-plus of raw coal . Examine the power used at power plants. The efficiency of the blowers, water pumps,
Multi-MW Closed Cycle MHD Nuclear Space Power Via Nonequilibrium He/Xe Working Plasma
NASA Technical Reports Server (NTRS)
Litchford, Ron J.; Harada, Nobuhiro
2011-01-01
Prospects for a low specific mass multi-megawatt nuclear space power plant were examined assuming closed cycle coupling of a high-temperature fission reactor with magnetohydrodynamic (MHD) energy conversion and utilization of a nonequilibrium helium/xenon frozen inert plasma (FIP). Critical evaluation of performance attributes and specific mass characteristics was based on a comprehensive systems analysis assuming a reactor operating temperature of 1800 K for a range of subsystem mass properties. Total plant efficiency was expected to be 55.2% including plasma pre-ionization power, and the effects of compressor stage number, regenerator efficiency and radiation cooler temperature on plant efficiency were assessed. Optimal specific mass characteristics were found to be dependent on overall power plant scale with 3 kg/kWe being potentially achievable at a net electrical power output of 1-MWe. This figure drops to less than 2 kg/kWe when power output exceeds 3 MWe. Key technical issues include identification of effective methods for non-equilibrium pre-ionization and achievement of frozen inert plasma conditions within the MHD generator channel. A three-phase research and development strategy is proposed encompassing Phase-I Proof of Principle Experiments, a Phase-II Subscale Power Generation Experiment, and a Phase-III Closed-Loop Prototypical Laboratory Demonstration Test.
Analysis of UF6 breeder reactor power plants
NASA Technical Reports Server (NTRS)
Clement, J. D.; Rust, J. H.
1976-01-01
Gaseous UF6 fueled breeder reactor design and technical applications of such concepts are summarized. Special attention was given to application in nuclear power plants and to reactor efficiency and safety factors.
Kostova, I.J.; Hower, J.C.; Mastalerz, Maria; Vassilev, S.V.
2011-01-01
Mercury capture by fly ash C was investigated at five lignite- and subbituminous-coal-burning Bulgarian power plants (Republika, Bobov Dol, Maritza East 2, Maritza East 3, and Sliven). Although the C content of the ashes is low, never exceeding 1.6%, the Hg capture on a unit C basis demonstrates that the low-rank-coal-derived fly ash carbons are more efficient in capturing Hg than fly ash carbons from bituminous-fired power plants. While some low-C and low-Hg fly ashes do not reveal any trends of Hg versus C, the 2nd and, in particular, the 3rd electrostatic precipitator (ESP) rows at the Republika power plant do have sufficient fly ash C range and experience flue gas sufficiently cool to capture measurable amounts of Hg. The Republika 3rd ESP row exhibits an increase in Hg with increasing C, as observed in other power plants, for example, in Kentucky power plants burning Appalachian-sourced bituminous coals. Mercury/C decreases with an increase in fly ash C, suggesting that some of the C is isolated from the flue gas stream and does not contribute to Hg capture. Mercury capture increases with an increase in Brunauer-Emmett-Teller (BET) surface area and micropore surface area. The differences in Hg capture between the Bulgarian plants burning low-rank coal and high volatile bituminous-fed Kentucky power plants suggests that the variations in C forms resulting from the combustion of the different ranks also influence the efficiency of Hg capture. ?? 2010 Elsevier Ltd.
Improving urban district heating systems and assessing the efficiency of the energy usage therein
NASA Astrophysics Data System (ADS)
Orlov, M. E.; Sharapov, V. I.
2017-11-01
The report describes issues in connection with improving urban district heating systems from combined heat power plants (CHPs), to propose the ways for improving the reliability and the efficiency of the energy usage (often referred to as “energy efficiency”) in such systems. The main direction of such urban district heating systems improvement suggests transition to combined heating systems that include structural elements of both centralized and decentralized systems. Such systems provide the basic part of thermal power via highly efficient methods for extracting thermal power plants turbines steam, while peak loads are covered by decentralized peak thermal power sources to be mounted at consumers’ locations, with the peak sources being also reserve thermal power sources. The methodology was developed for assessing energy efficiency of the combined district heating systems, implemented as a computer software product capable of comparatively calculating saving on reference fuel for the system.
(Power sector efficiency analysis in Costa Rica). [Power Sector Efficiency Analysis in Costa Rica
DOE Office of Scientific and Technical Information (OSTI.GOV)
Waddle, D.B.
I traveled to San Jose, Costa Rica, to review the state of the electric power utility with a team of specialists, including a transmission and distribution specialist, a hydroelectric engineering specialist, and a thermal power plant specialist. The purpose of the mission was to determine the costs and benefits of efficiency improvements to supply side technologies employed by the Instituto Costarricense de Electricidad, the national power company in Costa Rica, and the potential contribution of these efficiency measures to the future electric power needs of Costa Rica.
How to Boost Power House Efficiency
ERIC Educational Resources Information Center
Gardner, John C.
1977-01-01
A study of a university power plant and its efficiency determined the total available steam generating capacity of the existing boilers and the physical conditions that were limiting that capacity. (Author/MLF)
Climate Change Impacts on Rivers and Implications for Electricity Generation in the United States
NASA Astrophysics Data System (ADS)
Miara, A.; Vorosmarty, C. J.; Macknick, J.; Corsi, F.; Cohen, S. M.; Tidwell, V. C.; Newmark, R. L.; Prousevitch, A.
2015-12-01
The contemporary power sector in the United States is heavily reliant on water resources to provide cooling water for thermoelectric generation. Efficient thermoelectric plant operations require large volumes of water at sufficiently cool temperatures for their cooling process. The total amount of water that is withdrawn or consumed for cooling and any potential declines in efficiencies are determined by the sector's fuel mix and cooling technologies. As such, the impact of climate change, and the extent of impact, on the power sector is shaped by the choice of electricity generation technologies that will be built over the coming decades. In this study, we model potential changes in river discharge and temperature in the contiguous US under a set of climate scenarios to year 2050 using the Water Balance Model-Thermoelectric Power and Thermal Pollution Model (WBM-TP2M). Together, these models quantify, in high-resolution (3-min), river temperatures, discharge and power plant efficiency losses associated with changes in available cooling water that incorporates climate, hydrology, river network dynamics and multi-plant impacts, on both single power plant and regional scales. Results are used to assess the aptness and vulnerability of contemporary and alternative electricity generation pathways to changes in climate and water availability for cooling purposes, and the concomitant impacts on power plant operating efficiencies. We assess the potential impacts by comparing six regions (Northeast, Southeast, Midwest, Great Plains, Southwest, Northwest as in the National Climate Assessment (2014)) across the US. These experiments allow us to assess tradeoffs among electricity-water-climate to provide useful insight for decision-makers managing regional power production and aquatic environments.
Control of Solar Power Plants Connected Grid with Simple Calculation Method on Residential Homes
NASA Astrophysics Data System (ADS)
Kananda, Kiki; Nazir, Refdinal
2017-12-01
One of the most compatible renewable energy in all regions to apply is solar energy. Solar power plants can be built connected to existing or stand-alone power grids. In assisting the residential electricity in which there is a power grid, then a small scale solar energy power plants is very appropriate. However, the general constraint of solar energy power plants is still low in terms of efficiency. Therefore, this study will explain how to control the power of solar power plants more optimally, which is expected to reactive power to zero to raise efficiency. This is a continuation of previous research using Newton Rapshon control method. In this study we introduce a simple method by using ordinary mathematical calculations of solar-related equations. In this model, 10 PV modules type of ND T060M1 with a 60 Wp capacity are used. The calculations performed using MATLAB Simulink provide excellent value. For PCC voltage values obtained a stable quantity of approximately 220 V. At a maximum irradiation condition of 1000 W / m2, the reactive power value of Q solar generating system maximum 20.48 Var and maximum active power of 417.5 W. In the condition of lower irradiation, value of reactive power Q almost close to zero 0.77Var. This simple mathematical method can provide excellent quality control power values.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Energy Operation Model (EOM) simulates the operation of the electric grid at the zonal scale, including inter-zonal transmission constraints. It generates the production cost, power generation by plant and category, fuel usage, and locational marginal price (LMP) with a flexible way to constrain the power production by environmental constraints, e.g. heat waves, drought conditions). Different from commercial software such as PROMOD IV where generator capacity and heat rate efficiency can only be adjusted on a monthly basis, EOM calculates capacity impacts and plant efficiencies based on hourly ambient conditions (air temperature and humidity) and cooling water availability for thermal plants.more » What is missing is a hydro power dispatch.« less
NASA Technical Reports Server (NTRS)
Hoover, D. Q.
1976-01-01
Electric power plant costs and efficiencies are presented for three basic open-cycle MHD systems: (1) direct coal fired system, (2) a system with a separately fired air heater, and (3) a system burning low-Btu gas from an integrated gasifier. Power plant designs were developed corresponding to the basic cases with variation of major parameters for which major system components were sized and costed. Flow diagrams describing each design are presented. A discussion of the limitations of each design is made within the framework of the assumptions made.
Human reliability and plant operating efficiency: Are 12-hour work schedules cause for concern
DOE Office of Scientific and Technical Information (OSTI.GOV)
Baker, T.L.
1992-01-01
Since the introduction of 12-h shifts to the US nuclear power industry only 8 yr ago, compressed workweek schedules have proliferated among operations departments at a phenomenal rate. Many plants that continue to use 8-h shifts during normal operations routinely change to scheduled 12-h shifts during refueling or maintenance outages. The most critical issue in the use of extended work shifts is whether alertness, physical stamina, or mental performance are compromised to the point of reducing safety or efficiency of nuclear power plant operation. Laboratory and field research sponsored by the National Institute of Occupational Safety and Health suggests thatmore » alertness, measured by self-ratings, and mental performance, measured by computer-based performance tests, are impaired on 12-h shifts compared with 8-h shifts. In contrast to these findings, plant operating efficiency and operator performance have been rated as improved in two field studies conducted in operating nuclear power plants (Fast Flux Test Facility, Washington and Ontario Hydro, Canada). A recent Electric Power Research Institute review of nuclear industry experience with 12-h shifts also suggests an overwhelmingly positive rating of 12-h schedules from both control room operators and management.« less
Ganguli, Rajive; Bandopadhyay, Sukumar
2012-01-01
Tmore » he impact of particle size distribution (PSD) of pulverized, low rank high volatile content Alaska coal on combustion related power plant performance was studied in a series of field scale tests. Performance was gauged through efficiency (ratio of megawatt generated to energy consumed as coal), emissions (SO 2 , NO x , CO), and carbon content of ash (fly ash and bottom ash). he study revealed that the tested coal could be burned at a grind as coarse as 50% passing 76 microns, with no deleterious impact on power generation and emissions. he PSD’s tested in this study were in the range of 41 to 81 percent passing 76 microns. here was negligible correlation between PSD and the followings factors: efficiency, SO 2 , NO x , and CO. Additionally, two tests where stack mercury (Hg) data was collected, did not demonstrate any real difference in Hg emissions with PSD. he results from the field tests positively impacts pulverized coal power plants that burn low rank high volatile content coals (such as Powder River Basin coal). hese plants can potentially reduce in-plant load by grinding the coal less (without impacting plant performance on emissions and efficiency) and thereby, increasing their marketability.« less
NASA Astrophysics Data System (ADS)
Curletti, F.; Gandiglio, M.; Lanzini, A.; Santarelli, M.; Maréchal, F.
2015-10-01
This article investigates the techno-economic performance of large integrated biogas Solid Oxide Fuel Cell (SOFC) power plants. Both atmospheric and pressurized operation is analysed with CO2 vented or captured. The SOFC module produces a constant electrical power of 1 MWe. Sensitivity analysis and multi-objective optimization are the mathematical tools used to investigate the effects of Fuel Utilization (FU), SOFC operating temperature and pressure on the plant energy and economic performances. FU is the design variable that most affects the plant performance. Pressurized SOFC with hybridization with a gas turbine provides a notable boost in electrical efficiency. For most of the proposed plant configurations, the electrical efficiency ranges in the interval 50-62% (LHV biogas) when a trade-off of between energy and economic performances is applied based on Pareto charts obtained from multi-objective plant optimization. The hybrid SOFC is potentially able to reach an efficiency above 70% when FU is 90%. Carbon capture entails a penalty of more 10 percentage points in pressurized configurations mainly due to the extra energy burdens of captured CO2 pressurization and oxygen production and for the separate and different handling of the anode and cathode exhausts and power recovery from them.
Carbonated Science Cleans Power Plants
DOE Office of Scientific and Technical Information (OSTI.GOV)
Rousseau, Roger; Heldebrant, David; Glezakou, Vand
Similar to the properties of soda, liquid solvents can efficiently capture and convert carbon dioxide from coal power plants. Researchers at PNNL explain this process and how this method can turn captured carbon into plastic or fuel.
SMALL SCALE BIOMASS FUELED GAS TURBINE ENGINE
A new generation of small scale (less than 20 MWe) biomass fueled, power plants are being developed based on a gas turbine (Brayton cycle) prime mover. These power plants are expected to increase the efficiency and lower the cost of generating power from fuels such as wood. The n...
78 FR 70588 - STP Nuclear Operating Company; South Texas Project
Federal Register 2010, 2011, 2012, 2013, 2014
2013-11-26
... efficiency; (8) wind power; (9) solar power; (10) hydroelectric power; (11) ocean wave and current energy... generic environmental impact statement for license renewal of nuclear plants; issuance. SUMMARY: Notice is hereby given that the U.S. Nuclear Regulatory Commission (NRC) has published the final, plant-specific...
Energy analysis of coal, fission, and fusion power plants
NASA Astrophysics Data System (ADS)
Tsoulfanidis, N.
1981-04-01
The method of net energy analysis has been applied to coal, fission, and fusion power plants. Energy consumption over the lifetime of the plants has been calculated for construction, operation and maintenance, fuel, public welfare, and land use and restoration. Thermal and electric energy requirements were obtained separately for each energy consuming sector. The results of the study are presented in three ways: total energy requirements, energy gain ratio, and payback periods. All three types of power plants are net producers of energy. The coal and fusion power plants are superior to fission plants from the energy efficiency point of view. Fission plants will improve considerably if the centrifuge replaces the gaseous diffusion as a method of enrichment.
NASA Astrophysics Data System (ADS)
Campanari, Stefano; Mastropasqua, Luca; Gazzani, Matteo; Chiesa, Paolo; Romano, Matteo C.
2016-09-01
An important advantage of solid oxide fuel cells (SOFC) as future systems for large scale power generation is the possibility of being efficiently integrated with processes for CO2 capture. Focusing on natural gas power generation, Part A of this work assessed the performances of advanced pressurised and atmospheric plant configurations (SOFC + GT and SOFC + ST, with fuel cell integration within a gas turbine or a steam turbine cycle) without CO2 separation. This Part B paper investigates such kind of power cycles when applied to CO2 capture, proposing two ultra-high efficiency plant configurations based on advanced intermediate-temperature SOFCs with internal reforming and low temperature CO2 separation process. The power plants are simulated at the 100 MW scale with a set of realistic assumptions about FC performances, main components and auxiliaries, and show the capability of exceeding 70% LHV efficiency with high CO2 capture (above 80%) and a low specific primary energy consumption for the CO2 avoided (1.1-2.4 MJ kg-1). Detailed results are presented in terms of energy and material balances, and a sensitivity analysis of plant performance is developed vs. FC voltage and fuel utilisation to investigate possible long-term improvements. Options for further improvement of the CO2 capture efficiency are also addressed.
Schivley, Greg; Ingwersen, Wesley W; Marriott, Joe; Hawkins, Troy R; Skone, Timothy J
2015-07-07
Improvements to coal power plant technology and the cofired combustion of biomass promise direct greenhouse gas (GHG) reductions for existing coal-fired power plants. Questions remain as to what the reduction potentials are from a life cycle perspective and if it will result in unintended increases in impacts to air and water quality and human health. This study provides a unique analysis of the potential environmental impact reductions from upgrading existing subcritical pulverized coal power plants to increase their efficiency, improving environmental controls, cofiring biomass, and exporting steam for industrial use. The climate impacts are examined in both a traditional-100 year GWP-method and a time series analysis that accounts for emission and uptake timing over the life of the power plant. Compared to fleet average pulverized bed boilers (33% efficiency), we find that circulating fluidized bed boilers (39% efficiency) may provide GHG reductions of about 13% when using 100% coal and reductions of about 20-37% when cofiring with 30% biomass. Additional greenhouse gas reductions from combined heat and power are minimal if the steam coproduct displaces steam from an efficient natural gas boiler. These upgrades and cofiring biomass can also reduce other life cycle impacts, although there may be increased impacts to water quality (eutrophication) when using biomass from an intensely cultivated source. Climate change impacts are sensitive to the timing of emissions and carbon sequestration as well as the time horizon over which impacts are considered, particularly for long growth woody biomass.
Zhang, Yifei; Kang, Jian
2017-11-01
The building of biomass combined heat and power (CHP) plants is an effective means of developing biomass energy because they can satisfy demands for winter heating and electricity consumption. The purpose of this study was to analyse the effect of the distribution density of a biomass CHP plant network on heat utilisation efficiency in a village-town system. The distribution density is determined based on the heat transmission threshold, and the heat utilisation efficiency is determined based on the heat demand distribution, heat output efficiency, and heat transmission loss. The objective of this study was to ascertain the optimal value for the heat transmission threshold using a multi-scheme comparison based on an analysis of these factors. To this end, a model of a biomass CHP plant network was built using geographic information system tools to simulate and generate three planning schemes with different heat transmission thresholds (6, 8, and 10 km) according to the heat demand distribution. The heat utilisation efficiencies of these planning schemes were then compared by calculating the gross power, heat output efficiency, and heat transmission loss of the biomass CHP plant for each scenario. This multi-scheme comparison yielded the following results: when the heat transmission threshold was low, the distribution density of the biomass CHP plant network was high and the biomass CHP plants tended to be relatively small. In contrast, when the heat transmission threshold was high, the distribution density of the network was low and the biomass CHP plants tended to be relatively large. When the heat transmission threshold was 8 km, the distribution density of the biomass CHP plant network was optimised for efficient heat utilisation. To promote the development of renewable energy sources, a planning scheme for a biomass CHP plant network that maximises heat utilisation efficiency can be obtained using the optimal heat transmission threshold and the nonlinearity coefficient for local roads. Copyright © 2017 Elsevier Ltd. All rights reserved.
NASA Technical Reports Server (NTRS)
Staiger, P. J.; Penko, P. F.
1982-01-01
The conceptual design study of a potential early commercial MHD power plant (CSPEC) is described and the results are summarized. Each of two contractors did a conceptual design of an approximtely 1000 MWe open-cycle MHD/steam plant with oxygen enriched combustion air preheated to an intermediate temperatue in a metallic heat exchanger. The contractors were close in their overall plant efficiency estimates but differed in their capital cost and cost of electricity estimates, primarily because of differences in balance-of-plant material, contingency, and operating and maintenance cost estimates. One contractor concluded that its MHD plant design compared favorably in cost of electricity with conventional coal-fired steam plants. The other contractor is making such a comparison as part of a follow-on study. Each contractor did a preliminary investigation of part-load performance and plant availability. The results of NASA studies investigating the effect of plant size and oxidizer preheat temperature on the performance of CSPEC-type MHD plants are also described. The efficiency of a 1000 MWe plant is about three points higher than of a 200 MWe plant. Preheating to 1600 F gives an efficiency about one and one-half points higher than preheating to 800 F for all plant sizes. For each plant size and preheat temperature there is an oxidizer enrichment level and MHD generator length that gives the highest plant efficiency.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mark A. Johnson
2012-06-29
Lineage Power and Verizon teamed up to address a DOE funding opportunity focused on improving the power conversion chain in telecommunications facilities and data centers. The project had three significant elements: the design and development of high efficiency and high power three-phase rectifiers by Lineage Power, design and development of software to optimize overall plant energy efficiency by Lineage Power, and a field trial in active Verizon telecommunications facilities where energy consumption was measured before and after efficiency upgrades.
Study on integration potential of gas turbines and gas engines into parabolic trough power plants
NASA Astrophysics Data System (ADS)
Vogel, Tobias; Oeljeklaus, Gerd; Görner, Klaus
2017-06-01
Hybrid power plants represent an important intermediate step on the way to an energy supply structure based substantially on renewable energies. Natural gas is the preferred fossil fuel for hybridization of solar thermal power plants, due to its low specific CO2-emission and technical advantages by means of integration into the power plant process. The power plant SHAMS ONE serves as an exemplary object of this study. In order to facilitate peaker gas turbines in an economical way to a combined cycle approach, with the SGT-400 an industrial gas turbine of the 10-20 MWel class have been integrated into the base case power plant. The concept has been set up, to make use of the gas turbine waste heat for power generation and increasing the overall power plant efficiency of the hybrid power plant at the same time. This concept represents an alternative to the widely used concept of combined cycle power plants with solar heat integration. Supplementary, this paper also dedicates the alternative to use gas engines instead of gas turbines.
Waste heat recovery options in a large gas-turbine combined power plant
NASA Astrophysics Data System (ADS)
Upathumchard, Ularee
This study focuses on power plant heat loss and how to utilize the waste heat in energy recovery systems in order to increase the overall power plant efficiency. The case study of this research is a 700-MW natural gas combined cycle power plant, located in a suburban area of Thailand. An analysis of the heat loss of the combustion process, power generation process, lubrication system, and cooling system has been conducted to evaluate waste heat recovery options. The design of the waste heat recovery options depends to the amount of heat loss from each system and its temperature. Feasible waste heat sources are combustion turbine (CT) room ventilation air and lubrication oil return from the power plant. The following options are being considered in this research: absorption chillers for cooling with working fluids Ammonia-Water and Water-Lithium Bromide (in comparison) and Organic Rankine Cycle (ORC) with working fluids R134a and R245fa. The absorption cycles are modeled in three different stages; single-effect, double-effect and half-effect. ORC models used are simple ORC as a baseline, ORC with internal regenerator, ORC two-phase flash expansion ORC and ORC with multiple heat sources. Thermodynamic models are generated and each system is simulated using Engineering Equation Solver (EES) to define the most suitable waste heat recovery options for the power plant. The result will be synthesized and evaluated with respect to exergy utilization efficiency referred as the Second Law effectiveness and net output capacity. Results of the models give recommendation to install a baseline ORC of R134a and a double-effect water-lithium bromide absorption chiller, driven by ventilation air from combustion turbine compartment. The two technologies yield reasonable economic payback periods of 4.6 years and 0.7 years, respectively. The fact that this selected power plant is in its early stage of operation allows both models to economically and effectively perform waste heat recovery during the power plant's life span. Furthermore, the recommendation from this research will be submitted to the Electricity Generating Authority of Thailand (EGAT) for implementation. This study will also be used as an example for other power plants in Thailand to consider waste energy utilization to improve plant efficiency and sustain fuel resources in the future.
NASA Astrophysics Data System (ADS)
Eickhoff, Martin; Meyer-Grünefeldt, Mirko; Keller, Lothar
2016-05-01
Nowadays molten salt is efficiently used in point concentrating solar thermal power plants. Line focusing systems still have the disadvantage of elevated heat losses at night because of active freeze protection of the solar field piping system. In order to achieve an efficient operation of line focusing solar power plants using molten salt, a new plant design and a novel operating strategy is developed for Linear Fresnel- and Parabolic Trough power plants. Daily vespertine drainage of the solar field piping and daily matutinal refilling of the solar preheated absorber tubes eliminate the need of nocturnal heating of the solar field and reduce nocturnal heat losses to a minimum. The feasibility of this new operating strategy with all its sub-steps has been demonstrated experimentally.
NASA Technical Reports Server (NTRS)
Holman, R. R.; Lippert, T. E.
1976-01-01
Electric Power Plant costs and efficiencies are presented for two basic liquid-metal cycles corresponding to 922 and 1089 K (1200 and 1500 F) for a commercial applications using direct coal firing. Sixteen plant designs are considered for which major component equipment were sized and costed. The design basis for each major component is discussed. Also described is the overall systems computer model that was developed to analyze the thermodynamics of the various cycle configurations that were considered.
NASA Technical Reports Server (NTRS)
Deegan, P. B.
1976-01-01
Adding a metal vapor Rankine topper to a steam cycle was studied as a way to increase the mean temperature at which heat is added to the cycle to raise the efficiency of an electric power plant. Potassium and cesium topping fluids were considered. Pressurized fluidized bed or pressurized (with an integrated low-Btu gasifier) boilers were assumed. Included in the cycles was a pressurizing gas turbine with its associated recuperator, and a gas economizer and feedwater heater. One of the ternary systems studied shows plant efficiency of 42.3% with a plant capitalization of $66.7/kW and a cost of electricity of 8.19 mills/MJ (29.5 mills/kWh).
On the possibility of generation of cold and additional electric energy at thermal power stations
NASA Astrophysics Data System (ADS)
Klimenko, A. V.; Agababov, V. S.; Borisova, P. N.
2017-06-01
A layout of a cogeneration plant for centralized supply of the users with electricity and cold (ECCG plant) is presented. The basic components of the plant are an expander-generator unit (EGU) and a vapor-compression thermotransformer (VCTT). At the natural-gas-pressure-reducing stations, viz., gas-distribution stations and gas-control units, the plant is connected in parallel to a throttler and replaces the latter completely or partially. The plant operates using only the energy of the natural gas flow without burning the gas; therefore, it can be classified as a fuelless installation. The authors compare the thermodynamic efficiencies of a centralized cold supply system based on the proposed plant integrated into the thermal power station scheme and a decentralized cold supply system in which the cold is generated by electrically driven vapor-compression thermotransformers installed on the user's premises. To perform comparative analysis, the exergy efficiency was taken as the criterion since in one of the systems under investigation the electricity and the cold are generated, which are energies of different kinds. It is shown that the thermodynamic efficiency of the power supply using the proposed plant proves to be higher within the entire range of the parameters under consideration. The article presents the results of investigating the impact of the gas heating temperature upstream from the expander on the electric power of the plant, its total cooling capacity, and the cooling capacities of the heat exchangers installed downstream from the EGU and the evaporator of the VCTT. The results of calculations are discussed that show that the cold generated at the gas-control unit of a powerful thermal power station can be used for the centralized supply of the cold to the ventilation and conditioning systems of both the buildings of the power station and the neighboring dwelling houses, schools, and public facilities during the summer season.
All-regime combined-cycle plant: Engineering solutions
NASA Astrophysics Data System (ADS)
Berezinets, P. A.; Tumanovskii, G. G.; Tereshina, G. E.; Krylova, I. N.; Markina, V. N.; Migun, E. N.
2016-12-01
The development of distributed power generation systems as a supplement to the centralized unified power grid increases the operational stability and efficiency of the entire power generation industry and improves the power supply to consumers. An all-regime cogeneration combined-cycle plant with a power of 20-25 mW (PGU-20/25T) and an electrical efficiency above 50% has been developed at the All-Russia Thermal Engineering Institute (ATEI) as a distributed power generation object. The PGU-20/25T two-circuit cogeneration plant provides a wide electrical and thermal power adjustment range and the absence of the mutual effect of electrical and thermal power output regimes at controlled frequency and power in a unified or isolated grid. The PGU-20/25T combined-cycle plant incorporates a gas-turbine unit (GTU) with a power of 16 MW, a heat recovery boiler (HRB) with two burners (before the boiler and the last heating stage), and a cogeneration steam turbine with a power of 6/9 MW. The PGU-20/25T plant has a maximum electrical power of 22 MW and an efficiency of 50.8% in the heat recovery regime and a maximum thermal power output of 16.3 MW (14 Gcal/h) in the cogeneration regime. The use of burners can increase the electrical power to 25 MW in the steam condensation regime at an efficiency of 49% and the maximum thermal power output to 29.5 MW (25.4 Gcal/h). When the steam turbine is shut down, the thermal power output can grow to 32.6 MW (28 Gcal/h). The innovative equipment, which was specially developed for PGU-20/25T, improves the reliability of this plant and simplifies its operation. Among this equipment are microflame burners in the heat recovery boiler, a vacuum system based on liquid-ring pumps, and a vacuum deaerator. To enable the application of PGU-20/25T in water-stressed regions, an air condenser preventing the heat-transfer tubes from the risk of covering with ice during operation in frost air has been developed. The vacuum system eliminates the need for an extraneous source of steam for the startup of the PGU-20/25T plant. The vacuum deaerator provides prestartup deaeration and the filling of the entire condensate feed pipeline with deaerated water and also enables the maintenance of the water temperature before the boiler at a level of no lower than 60°C and the oxygen content at a level of no higher than 10 μg/L during operation under load. The microflame burners in the heat recovery boiler enable the independent adjustment of the electrical power and the thermal power output from the PGU-20/25T plant. All the innovative equipment has been tested on experimental prototypes.
Quantity, Quality, and Availability of Waste Heat from United States Thermal Power Generation.
Gingerich, Daniel B; Mauter, Meagan S
2015-07-21
Secondary application of unconverted heat produced during electric power generation has the potential to improve the life-cycle fuel efficiency of the electric power industry and the sectors it serves. This work quantifies the residual heat (also known as waste heat) generated by U.S. thermal power plants and assesses the intermittency and transport issues that must be considered when planning to utilize this heat. Combining Energy Information Administration plant-level data with literature-reported process efficiency data, we develop estimates of the unconverted heat flux from individual U.S. thermal power plants in 2012. Together these power plants discharged an estimated 18.9 billion GJ(th) of residual heat in 2012, 4% of which was discharged at temperatures greater than 90 °C. We also characterize the temperature, spatial distribution, and temporal availability of this residual heat at the plant level and model the implications for the technical and economic feasibility of its end use. Increased implementation of flue gas desulfurization technologies at coal-fired facilities and the higher quality heat generated in the exhaust of natural gas fuel cycles are expected to increase the availability of residual heat generated by 10.6% in 2040.
Ma, Z.; Mehos, M.; Glatzmaier, G.; ...
2015-05-01
Concentrating solar power (CSP) is an effective way to convert solar energy into electricity with an economic energy-storage capability for grid-scale, dispatchable renewable power generation. However, CSP plants need to reduce costs to be competitive with other power generation methods. Two ways to reduce CSP cost are to increase solar-to-electric efficiency by supporting a high-efficiency power conversion system, and to use low-cost materials in the system. The current nitrate-based molten-salt systems have limited potential for cost reduction and improved power-conversion efficiency with high operating temperatures. Even with significant improvements in operating performance, these systems face challenges in satisfying the costmore » and performance targets. This paper introduces a novel CSP system with high-temperature capability that can be integrated into a high-efficiency CSP plant and that meets the low-cost, high-performance CSP targets. Unlike a conventional salt-based CSP plant, this design uses gas/solid, two-phase flow as the heat-transfer fluid (HTF); separated solid particles as storage media; and stable, inexpensive materials for the high-temperature receiver and energy storage containment. We highlight the economic and performance benefits of this innovative CSP system design, which has thermal energy storage capability for base-load power generation.« less
NASA Astrophysics Data System (ADS)
Dutta, Rohan; Ghosh, Parthasarathi; Chowdhury, Kanchan
2017-12-01
Diverse power generation sector requires energy storage due to penetration of variable renewable energy sources and use of CO2 capture plants with fossil fuel based power plants. Cryogenic energy storage being large-scale, decoupled system with capability of producing large power in the range of MWs is one of the options. The drawback of these systems is low turnaround efficiencies due to liquefaction processes being highly energy intensive. In this paper, the scopes of improving the turnaround efficiency of such a plant based on liquid Nitrogen were identified and some of them were addressed. A method using multiple stages of reheat and expansion was proposed for improved turnaround efficiency from 22% to 47% using four such stages in the cycle. The novelty here is the application of reheating in a cryogenic system and utilization of waste heat for that purpose. Based on the study, process conditions for a laboratory-scale setup were determined and presented here.
NASA Astrophysics Data System (ADS)
Tong, D.; Zhang, Q.
2017-12-01
As the largest energy infrastructure in China, power sector consumed more coal than any other sector and threatened air quality and greenhouse gas (GHG) abatement target. In this work, we assessed the evolution of coal-fired power plants in China during 2010-2030 and the evolution of associated emissions for the same period by using a unit-based emission projection model which integrated the historical power plants information, turnover of the future power plant fleet, and the evolution of end-of-pipe control technologies. We found that, driven by the stringent environmental legislation, SO2, NOx, and PM2.5 emissions from China's coal-fired power plants decreased by 49%, 45%, and 24% respectively during 2010-2015, comparing to 14% increase of coal consumption and 15% increase in CO2 emissions. We estimated that under current national energy development planning, coal consumption and CO2 emissions from coal-fired power plants will continue to increase until 2030, in which against the China's Intended Nationally Determined Contributions (INDCs) targets. Early retirement of old and low-efficient power plants will cumulatively reduce 2.2 Pg CO2 emissions from the baseline scenario during 2016-2030, but still could not curb CO2 emissions from the peak before 2030. Owing to the implementation of "near zero" emission control policy, we projected that emissions of air pollutants will significantly decrease during the same period under all scenarios, indicating the decoupling trends of air pollutants and CO2 emissions. Although with limited direct emission reduction benefits, increasing operating hours of power plants could avoid 236 GW of new power plants construction, which could indirectly reduce emissions embodied in the construction activity. Our results identified a more sustainable pathway for China's coal-fired power plants, which could reduce air pollutant emissions, improve the energy efficiency, and slow down the construction of new units. However, continuous construction of new coal-fired power plants driven by increased electricity demand would pose a potential threat to climate change mitigation and China's peak carbon pledge, and more aggressive CO2 emission reduction policy should be implemented in the future.
Transmission system protection screening for integration of offshore wind power plants
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sajadi, A.; Strezoski, L.; Clark, K.
This paper develops an efficient methodology for protection screening of large-scale transmission systems as part of the planning studies for the integration of offshore wind power plants into the power grid. This methodology avails to determine whether any upgrades are required to the protection system. The uncertainty is considered in form of variability of the power generation by offshore wind power plant. This paper uses the integration of a 1000 MW offshore wind power plant operating in Lake Erie into the FirstEnergy/PJM service territory as a case study. This study uses a realistic model of a 63,000-bus test system thatmore » represents the U.S. Eastern Interconnection.« less
Transmission system protection screening for integration of offshore wind power plants
Sajadi, A.; Strezoski, L.; Clark, K.; ...
2018-02-21
This paper develops an efficient methodology for protection screening of large-scale transmission systems as part of the planning studies for the integration of offshore wind power plants into the power grid. This methodology avails to determine whether any upgrades are required to the protection system. The uncertainty is considered in form of variability of the power generation by offshore wind power plant. This paper uses the integration of a 1000 MW offshore wind power plant operating in Lake Erie into the FirstEnergy/PJM service territory as a case study. This study uses a realistic model of a 63,000-bus test system thatmore » represents the U.S. Eastern Interconnection.« less
Method and apparatus for improving the performance of a steam driven power system by steam mixing
Tsiklauri, Georgi V.; Durst, Bruce M.; Prichard, Andrew W.; Reid, Bruce D.; Burritt, James
1998-01-01
A method and apparatus for improving the efficiency and performance of a steam driven power plant wherein addition of steam handling equipment to an existing plant results in a surprising increase in plant performance. For Example, a gas turbine electrical generation system with heat recovery boiler may be installed along with a micro-jet high pressure and a low pressure mixer superheater. Depending upon plant characteristics, the existing moisture separator reheater (MSR) can be either augmented or done away with. The instant invention enables a reduction in T.sub.hot without a derating of the reactor unit, and improves efficiency of the plant's electrical conversion cycle. Coupled with this advantage is a possible extension of the plant's fuel cycle length due to an increased electrical conversion efficiency. The reduction in T.sub.hot further allows for a surprising extension of steam generator life. An additional advantage is the reduction in erosion/corrosion of secondary system components including turbine blades and diaphragms. The gas turbine generator used in the instant invention can also replace or augment existing peak or emergency power needs. Another benefit of the instant invention is the extension of plant life and the reduction of downtime due to refueling.
Development and design of photovoltaic power prediction system
NASA Astrophysics Data System (ADS)
Wang, Zhijia; Zhou, Hai; Cheng, Xu
2018-02-01
In order to reduce the impact of power grid safety caused by volatility and randomness of the energy produced in photovoltaic power plants, this paper puts forward a construction scheme on photovoltaic power generation prediction system, introducing the technical requirements, system configuration and function of each module, and discussing the main technical features of the platform software development. The scheme has been applied in many PV power plants in the northwest of China. It shows that the system can produce reasonable prediction results, providing a right guidance for dispatching and efficient running for PV power plant.
NASA Astrophysics Data System (ADS)
Aziz, Nur Liyana Afiqah Abdul; Siah Yap, Keem; Afif Bunyamin, Muhammad
2013-06-01
This paper presents a new approach of the fault detection for improving efficiency of circulating water system (CWS) in a power generation plant using a hybrid Fuzzy Logic System (FLS) and Extreme Learning Machine (ELM) neural network. The FLS is a mathematical tool for calculating the uncertainties where precision and significance are applied in the real world. It is based on natural language which has the ability of "computing the word". The ELM is an extremely fast learning algorithm for neural network that can completed the training cycle in a very short time. By combining the FLS and ELM, new hybrid model, i.e., FLS-ELM is developed. The applicability of this proposed hybrid model is validated in fault detection in CWS which may help to improve overall efficiency of power generation plant, hence, consuming less natural recourses and producing less pollutions.
Case study on incentive mechanism of energy efficiency retrofit in coal-fueled power plant in China.
Yuan, Donghai; Guo, Xujing; Cao, Yuan; He, Liansheng; Wang, Jinggang; Xi, Beidou; Li, Junqi; Ma, Wenlin; Zhang, Mingshun
2012-01-01
An ordinary steam turbine retrofit project is selected as a case study; through the retrofit, the project activities will generate emission reductions within the power grid for about 92,463 tCO(2)e per annum. The internal rate of return (IRR) of the project is only -0.41% without the revenue of carbon credits, for example, CERs, which is much lower than the benchmark value of 8%. Only when the unit price of carbon credit reaches 125 CNY/tCO(2), the IRR could reach the benchmark and an effective carbon tax needs to increase the price of carbon to 243 CNY/tce in order to make the project financially feasible. Design of incentive mechanism will help these low efficiency enterprises improve efficiency and reduce CO(2) emissions, which can provide the power plants sufficient incentive to implement energy efficiency retrofit project in existing coal-fuel power generation-units, and we hope it will make a good demonstration for the other low efficiency coal-fueled power generation units in China.
Case Study on Incentive Mechanism of Energy Efficiency Retrofit in Coal-Fueled Power Plant in China
Yuan, Donghai; Guo, Xujing; Cao, Yuan; He, Liansheng; Wang, Jinggang; Xi, Beidou; Li, Junqi; Ma, Wenlin; Zhang, Mingshun
2012-01-01
An ordinary steam turbine retrofit project is selected as a case study; through the retrofit, the project activities will generate emission reductions within the power grid for about 92,463 tCO2e per annum. The internal rate of return (IRR) of the project is only −0.41% without the revenue of carbon credits, for example, CERs, which is much lower than the benchmark value of 8%. Only when the unit price of carbon credit reaches 125 CNY/tCO2, the IRR could reach the benchmark and an effective carbon tax needs to increase the price of carbon to 243 CNY/tce in order to make the project financially feasible. Design of incentive mechanism will help these low efficiency enterprises improve efficiency and reduce CO2 emissions, which can provide the power plants sufficient incentive to implement energy efficiency retrofit project in existing coal-fuel power generation-units, and we hope it will make a good demonstration for the other low efficiency coal-fueled power generation units in China. PMID:23365532
Research on the Intensive Material Management System of Biomass Power Plant
NASA Astrophysics Data System (ADS)
Zhang, Ruosi; Hao, Tianyi; Li, Yunxiao; Zhang, Fangqing; Ding, Sheng
2017-05-01
In view of the universal problem which the material management is loose, and lack of standardization and interactive real-time in the biomass power plant, a system based on the method of intensive management is proposed in this paper to control the whole process of power plant material. By analysing the whole process of power plant material management and applying the Internet of Things, the method can simplify the management process. By making use of the resources to maximize and data mining, material utilization, circulation rate and quality control management can be improved. The system has been applied in Gaotang power plant, which raised the level of materials management and economic effectiveness greatly. It has an important significance for safe, cost-effective and highly efficient operation of the plant.
Coal-fired high performance power generating system. Final report
DOE Office of Scientific and Technical Information (OSTI.GOV)
NONE
As a result of the investigations carried out during Phase 1 of the Engineering Development of Coal-Fired High-Performance Power Generation Systems (Combustion 2000), the UTRC-led Combustion 2000 Team is recommending the development of an advanced high performance power generation system (HIPPS) whose high efficiency and minimal pollutant emissions will enable the US to use its abundant coal resources to satisfy current and future demand for electric power. The high efficiency of the power plant, which is the key to minimizing the environmental impact of coal, can only be achieved using a modern gas turbine system. Minimization of emissions can bemore » achieved by combustor design, and advanced air pollution control devices. The commercial plant design described herein is a combined cycle using either a frame-type gas turbine or an intercooled aeroderivative with clean air as the working fluid. The air is heated by a coal-fired high temperature advanced furnace (HITAF). The best performance from the cycle is achieved by using a modern aeroderivative gas turbine, such as the intercooled FT4000. A simplified schematic is shown. In the UTRC HIPPS, the conversion efficiency for the heavy frame gas turbine version will be 47.4% (HHV) compared to the approximately 35% that is achieved in conventional coal-fired plants. This cycle is based on a gas turbine operating at turbine inlet temperatures approaching 2,500 F. Using an aeroderivative type gas turbine, efficiencies of over 49% could be realized in advanced cycle configuration (Humid Air Turbine, or HAT). Performance of these power plants is given in a table.« less
Perna, Alessandra; Minutillo, Mariagiovanna; Lubrano Lavadera, Antonio; Jannelli, Elio
2018-03-01
The waste to energy (WtE) facilities and the renewable energy storage systems have a strategic role in the promotion of the "eco-innovation", an emerging priority in the European Union. This paper aims to propose advanced plant configurations in which waste to energy plants and electric energy storage systems from intermittent renewable sources are combined for obtaining more efficient and clean energy solutions in accordance with the "eco-innovation" approach. The advanced plant configurations consist of an electric energy storage (EES) section based on a solid oxide electrolyzer (SOEC), a waste gasification section based on the plasma technology and a power generation section based on a solid oxide fuel cell (SOFC). The plant configurations differ for the utilization of electrolytic hydrogen and oxygen in the plasma gasification section and in the power generation section. In the first plant configuration IAPGFC (Integrated Air Plasma Gasification Fuel Cell), the renewable oxygen enriches the air stream, that is used as plasma gas in the gasification section, and the renewable hydrogen is used to enrich the anodic stream of the SOFC in the power generation section. In the second plant configuration IHPGFC (Integrated Hydrogen Plasma Gasification Fuel Cell) the renewable hydrogen is used as plasma gas in the plasma gasification section, and the renewable oxygen is used to enrich the cathodic stream of the SOFC in the power generation section. The analysis has been carried out by using numerical models for predicting and comparing the systems performances in terms of electric efficiency and capability in realizing the waste to energy and the electric energy storage of renewable sources. Results have highlighted that the electric efficiency is very high for all configurations (35-45%) and, thanks to the combination with the waste to energy technology, the storage efficiencies are very attractive (in the range 72-92%). Copyright © 2017 Elsevier Ltd. All rights reserved.
Low-Rank Coal Grinding Performance Versus Power Plant Performance
DOE Office of Scientific and Technical Information (OSTI.GOV)
Rajive Ganguli; Sukumar Bandopadhyay
2008-12-31
The intent of this project was to demonstrate that Alaskan low-rank coal, which is high in volatile content, need not be ground as fine as bituminous coal (typically low in volatile content) for optimum combustion in power plants. The grind or particle size distribution (PSD), which is quantified by percentage of pulverized coal passing 74 microns (200 mesh), affects the pulverizer throughput in power plants. The finer the grind, the lower the throughput. For a power plant to maintain combustion levels, throughput needs to be high. The problem of particle size is compounded for Alaskan coal since it has amore » low Hardgrove grindability index (HGI); that is, it is difficult to grind. If the thesis of this project is demonstrated, then Alaskan coal need not be ground to the industry standard, thereby alleviating somewhat the low HGI issue (and, hopefully, furthering the salability of Alaskan coal). This project studied the relationship between PSD and power plant efficiency, emissions, and mill power consumption for low-rank high-volatile-content Alaskan coal. The emissions studied were CO, CO{sub 2}, NO{sub x}, SO{sub 2}, and Hg (only two tests). The tested PSD range was 42 to 81 percent passing 76 microns. Within the tested range, there was very little correlation between PSD and power plant efficiency, CO, NO{sub x}, and SO{sub 2}. Hg emissions were very low and, therefore, did not allow comparison between grind sizes. Mill power consumption was lower for coarser grinds.« less
Innovative open air brayton combined cycle systems for the next generation nuclear power plants
NASA Astrophysics Data System (ADS)
Zohuri, Bahman
The purpose of this research was to model and analyze a nuclear heated multi-turbine power conversion system operating with atmospheric air as the working fluid. The air is heated by a molten salt, or liquid metal, to gas heat exchanger reaching a peak temperature of 660 0C. The effects of adding a recuperator or a bottoming steam cycle have been addressed. The calculated results are intended to identify paths for future work on the next generation nuclear power plant (GEN-IV). This document describes the proposed system in sufficient detail to communicate a good understanding of the overall system, its components, and intended uses. The architecture is described at the conceptual level, and does not replace a detailed design document. The main part of the study focused on a Brayton --- Rankine Combined Cycle system and a Recuperated Brayton Cycle since they offer the highest overall efficiencies. Open Air Brayton power cycles also require low cooling water flows relative to other power cycles. Although the Recuperated Brayton Cycle achieves an overall efficiency slightly less that the Brayton --- Rankine Combined Cycle, it is completely free of a circulating water system and can be used in a desert climate. Detailed results of modeling a combined cycle Brayton-Rankine power conversion system are presented. The Rankine bottoming cycle appears to offer a slight efficiency advantage over the recuperated Brayton cycle. Both offer very significant advantages over current generation Light Water Reactor steam cycles. The combined cycle was optimized as a unit and lower pressure Rankine systems seem to be more efficient. The combined cycle requires a lot less circulating water than current power plants. The open-air Brayton systems appear to be worth investigating, if the higher temperatures predicted for the Next Generation Nuclear Plant do materialize.
Advanced binary geothermal power plants: Limits of performance
NASA Astrophysics Data System (ADS)
Bliem, C. J.; Mines, G. L.
1991-01-01
The Heat Cycle Research Program is investigating potential improvements to power cycles utilizing moderate temperature geothermal resources to produce electrical power. Investigations have specifically examined Rankine cycle binary power systems. Binary Rankine cycles are more efficient than the flash steam cycles at moderate resource temperature, achieving a higher net brine effectiveness. At resource conditions similar to those at the Heber binary plant, it has been shown that mixtures of saturated hydrocarbons (alkanes) or halogenated hydrocarbons operating in a supercritical Rankine cycle gave improved performance over Rankine cycles with the pure working fluids executing single or dual boiling cycles or supercritical cycles. Recently, other types of cycles have been proposed for binary geothermal service. The feasible limits on efficiency of a plant given practical limits on equipment performance is explored and the methods used in these advanced concept plants to achieve the maximum possible efficiency are discussed. (Here feasible is intended to mean reasonably achievable and not cost effective.) No direct economic analysis was made because of the sensitivity of economic results to site specific input. The limit of performance of three advanced plants were considered. The performance predictions were taken from the developers of each concept. The advanced plants considered appear to be approaching the feasible limit of performance. Ultimately, the plant designer must weigh the advantages and disadvantages of the the different cycles to find the best plant for a given service. In addition, a standard is presented of comparison of the work which has been done in the Heat Cycle Research Program and in the industrial sector by Exergy, Inc. and Polythermal Technologies.
Analysis of fuel cell hybrid locomotives
NASA Astrophysics Data System (ADS)
Miller, Arnold R.; Peters, John; Smith, Brian E.; Velev, Omourtag A.
Led by Vehicle Projects LLC, an international industry-government consortium is developing a 109 t, 1.2 MW road-switcher locomotive for commercial and military railway applications. As part of the feasibility and conceptual-design analysis, a study has been made of the potential benefits of a hybrid power plant in which fuel cells comprise the prime mover and a battery or flywheel provides auxiliary power. The potential benefits of a hybrid power plant are: (i) enhancement of transient power and hence tractive effort; (ii) regenerative braking; (iii) reduction of capital cost. Generally, the tractive effort of a locomotive at low speed is limited by wheel adhesion and not by available power. Enhanced transient power is therefore unlikely to benefit a switcher locomotive, but could assist applications that require high acceleration, e.g. subway trains with all axles powered. In most cases, the value of regeneration in locomotives is minimal. For low-speed applications such as switchers, the available kinetic energy and the effectiveness of traction motors as generators are both minimal. For high-speed heavy applications such as freight, the ability of the auxiliary power device to absorb a significant portion of the available kinetic energy is low. Moreover, the hybrid power plant suffers a double efficiency penalty, namely, losses occur in both absorbing and then releasing energy from the auxiliary device, which result in a net storage efficiency of no more than 50% for present battery technology. Capital cost in some applications may be reduced. Based on an observed locomotive duty cycle, a cost model shows that a hybrid power plant for a switcher may indeed reduce capital cost. Offsetting this potential benefit are the increased complexity, weight and volume of the power plant, as well as 20-40% increased fuel consumption that results from lower efficiency. Based on this analysis, the consortium has decided to develop a pure fuel cell road-switcher locomotive, that is, not a hybrid.
Entropy production and optimization of geothermal power plants
NASA Astrophysics Data System (ADS)
Michaelides, Efstathios E.
2012-09-01
Geothermal power plants are currently producing reliable and low-cost, base load electricity. Three basic types of geothermal power plants are currently in operation: single-flashing, dual-flashing, and binary power plants. Typically, the single-flashing and dual-flashing geothermal power plants utilize geothermal water (brine) at temperatures in the range of 550-430 K. Binary units utilize geothermal resources at lower temperatures, typically 450-380 K. The entropy production in the various components of the three types of geothermal power plants determines the efficiency of the plants. It is axiomatic that a lower entropy production would improve significantly the energy utilization factor of the corresponding power plant. For this reason, the entropy production in the major components of the three types of geothermal power plants has been calculated. It was observed that binary power plants generate the lowest amount of entropy and, thus, convert the highest rate of geothermal energy into mechanical energy. The single-flashing units generate the highest amount of entropy, primarily because they re-inject fluid at relatively high temperature. The calculations for entropy production provide information on the equipment where the highest irreversibilities occur, and may be used to optimize the design of geothermal processes in future geothermal power plants and thermal cycles used for the harnessing of geothermal energy.
Ways to Improve Russian Coal-Fired Power Plants
DOE Office of Scientific and Technical Information (OSTI.GOV)
Tumanovskii, A. G., E-mail: vti@vti.ru; Olkhovsky, G. G.
Coal is an important fuel for the electric power industry of Russia, especially in Ural and the eastern part of the country. It is fired in boilers of large (200 – 800 MW) condensing power units and in many cogeneration power plants with units rated at 50 – 180 MW. Many coal-fired power plants have been operated for more than 40 – 50 years. Though serviceable, their equipment is obsolete and does not comply with the current efficiency, environmental, staffing, and availability standards. It is urgent to retrofit and upgrade such power plants using advanced equipment, engineering and business ideas.more » Russian power-plant engineering companies have designed such advanced power units and their equipment such as boilers, turbines, auxiliaries, process and environmental control systems similar to those produced by the world’s leading manufacturers. Their performance and ways of implementation are discussed.« less
Oxygen-enriched air for MHD power plants
NASA Technical Reports Server (NTRS)
Ebeling, R. W., Jr.; Cutting, J. C.; Burkhart, J. A.
1979-01-01
Cryogenic air-separation process cycle variations and compression schemes are examined. They are designed to minimize net system power required to supply pressurized, oxygen-enriched air to the combustor of an MHD power plant with a coal input of 2000 MWt. Power requirements and capital costs for oxygen production and enriched air compression for enrichment levels from 13 to 50% are determined. The results are presented as curves from which total compression power requirements can be estimated for any desired enrichment level at any delivery pressure. It is found that oxygen enrichment and recuperative heating of MHD combustor air to 1400 F yields near-term power plant efficiencies in excess of 45%. A minimum power compression system requires 167 MW to supply 330 lb of oxygen per second and costs roughly 100 million dollars. Preliminary studies show MHD/steam power plants to be competitive with plants using high-temperature air preheaters burning gas.
More on duel purpose solar-electric power plants
NASA Astrophysics Data System (ADS)
Hall, F. F.
Rationale for such plants is reviewed and plant elements are listed. Dual purpose solar-electric plants would generate both electricity and hydrogen gas for conversion to ammonia or methanol or direct use as a fuel of unsurpassed specific power and cleanliness. By-product oxygen would also be sold to owners of hydrogen age equipment. Evolved gasses at high pressure could be fired in compressorless gas turbines, boilerless steam-turbines or fuel-cell-inverter hydrogen-electric power drives of high thermal efficiency as well as in conventional internal combustion engines.
The Role of Demand Response in Reducing Water-Related Power Plant Vulnerabilities
NASA Astrophysics Data System (ADS)
Macknick, J.; Brinkman, G.; Zhou, E.; O'Connell, M.; Newmark, R. L.; Miara, A.; Cohen, S. M.
2015-12-01
The electric sector depends on readily available water supplies for reliable and efficient operation. Elevated water temperatures or low water levels can trigger regulatory or plant-level decisions to curtail power generation, which can affect system cost and reliability. In the past decade, dozens of power plants in the U.S. have curtailed generation due to water temperatures and water shortages. Curtailments occur during the summer, when temperatures are highest and there is greatest demand for electricity. Climate change could alter the availability and temperature of water resources, exacerbating these issues. Constructing alternative cooling systems to address vulnerabilities can be capital intensive and can also affect power plant efficiencies. Demand response programs are being implemented by electric system planners and operators to reduce and shift electricity demands from peak usage periods to other times of the day. Demand response programs can also play a role in reducing water-related power sector vulnerabilities during summer months. Traditionally, production cost modeling and demand response analyses do not include water resources. In this effort, we integrate an electricity production cost modeling framework with water-related impacts on power plants in a test system to evaluate the impacts of demand response measures on power system costs and reliability. Specifically, we i) quantify the cost and reliability implications of incorporating water resources into production cost modeling, ii) evaluate the impacts of demand response measures on reducing system costs and vulnerabilities, and iii) consider sensitivity analyses with cooling systems to highlight a range of potential benefits of demand response measures. Impacts from climate change on power plant performance and water resources are discussed. Results provide key insights to policymakers and practitioners for reducing water-related power plant vulnerabilities via lower cost methods.
Analysis of Efficiency of the Ship Propulsion System with Thermochemical Recuperation of Waste Heat
NASA Astrophysics Data System (ADS)
Cherednichenko, Oleksandr; Serbin, Serhiy
2018-03-01
One of the basic ways to reduce polluting emissions of ship power plants is application of innovative devices for on-board energy generation by means of secondary energy resources. The combined gas turbine and diesel engine plant with thermochemical recuperation of the heat of secondary energy resources has been considered. It is suggested to conduct the study with the help of mathematical modeling methods. The model takes into account basic physical correlations, material and thermal balances, phase equilibrium, and heat and mass transfer processes. The paper provides the results of mathematical modeling of the processes in a gas turbine and diesel engine power plant with thermochemical recuperation of the gas turbine exhaust gas heat by converting a hydrocarbon fuel. In such a plant, it is possible to reduce the specific fuel consumption of the diesel engine by 20%. The waste heat potential in a gas turbine can provide efficient hydrocarbon fuel conversion at the ratio of powers of the diesel and gas turbine engines being up to 6. When the diesel engine and gas turbine operate simultaneously with the use of the LNG vapor conversion products, the efficiency coefficient of the plant increases by 4-5%.
Extended Durability Testing of an External Fuel Processor for a Solid Oxide Fuel Cell (SOFC)
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mark Perna; Anant Upadhyayula; Mark Scotto
2012-11-05
Durability testing was performed on an external fuel processor (EFP) for a solid oxide fuel cell (SOFC) power plant. The EFP enables the SOFC to reach high system efficiency (electrical efficiency up to 60%) using pipeline natural gas and eliminates the need for large quantities of bottled gases. LG Fuel Cell Systems Inc. (formerly known as Rolls-Royce Fuel Cell Systems (US) Inc.) (LGFCS) is developing natural gas-fired SOFC power plants for stationary power applications. These power plants will greatly benefit the public by reducing the cost of electricity while reducing the amount of gaseous emissions of carbon dioxide, sulfur oxides,more » and nitrogen oxides compared to conventional power plants. The EFP uses pipeline natural gas and air to provide all the gas streams required by the SOFC power plant; specifically those needed for start-up, normal operation, and shutdown. It includes a natural gas desulfurizer, a synthesis-gas generator and a start-gas generator. The research in this project demonstrated that the EFP could meet its performance and durability targets. The data generated helped assess the impact of long-term operation on system performance and system hardware. The research also showed the negative impact of ambient weather (both hot and cold conditions) on system operation and performance.« less
High Efficiency Nuclear Power Plants Using Liquid Fluoride Thorium Reactor Technology
NASA Technical Reports Server (NTRS)
Juhasz, Albert J.; Rarick, Richard A.; Rangarajan, Rajmohan
2009-01-01
An overall system analysis approach is used to propose potential conceptual designs of advanced terrestrial nuclear power plants based on Oak Ridge National Laboratory (ORNL) Molten Salt Reactor (MSR) experience and utilizing Closed Cycle Gas Turbine (CCGT) thermal-to-electric energy conversion technology. In particular conceptual designs for an advanced 1 GWe power plant with turbine reheat and compressor intercooling at a 950 K turbine inlet temperature (TIT), as well as near term 100 MWe demonstration plants with TITs of 950 and 1200 K are presented. Power plant performance data were obtained for TITs ranging from 650 to 1300 K by use of a Closed Brayton Cycle (CBC) systems code which considered the interaction between major sub-systems, including the Liquid Fluoride Thorium Reactor (LFTR), heat source and heat sink heat exchangers, turbo-generator machinery, and an electric power generation and transmission system. Optional off-shore submarine installation of the power plant is a major consideration.
NASA Astrophysics Data System (ADS)
Linkevics, O.; Ivanova, P.; Balodis, M.
2016-12-01
Intermittent generation (solar PV and wind energy) integration in power production portfolio as well as electricity price fluctuations have changed the running manner of conventional combined heat and power (CHP) plants: the shift from base load operation to running in cyclic modes. These cogeneration power plants are not adapted to new running conditions. The level of CHP plant flexibility should be improved to operate profitably and efficiently from both technical and fuel usage point of view. There are different ways to increase the flexibility of power plants. Before any improvements, the situation at power plants should be evaluated and the weakest points defined. In this publication, such measures are presented on Riga CHP-2 plant example: installation of heat storage tank; extension of operation rang; acceleration of start-ups.
NASA Astrophysics Data System (ADS)
Rahman, M. M.; Tan, J. H.; Fadzlita, M. T.; Khairul Muzammil, A. R. Wan
2017-07-01
Gravitational water vortex power plant is a green technology that generates electricity from alternative or renewable energy source. In the vortex power plant, water is introduced into a circular basin tangentially that creates a free vortex and energy is extracted from the free vortex by using a turbine. The main advantages of this type of power plant is the generation of electricity from ultra-low hydraulic pressure and it is also environmental friendly. Since the hydraulic head requirement is as low as 1m, this type of power plant can be installed at a river or a stream to generate electricity for few houses. It is a new and not well-developed technology to harvest electricity from low pressure water energy sources. There are limited literatures available on the design, fabrication and physical geometry of the vortex turbine and generator. Past researches focus on the optimization of turbine design, inlets, outlets and basin geometry. However, there are still insufficient literatures available for the technology to proceed beyond prototyping stage. The maximum efficiency obtained by the researchers are approximately 30% while the commercial companies claimed about 50% of efficiency with 500W to 20kW of power generated. Hence, the aim of this paper is to determine the gap in the vortex power plant technology development through past works and a set of research recommendations will be developed as efforts to accelerate the development of GWVPP.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Seiter, C.
1998-07-01
The use of coal power generation applications is currently enjoying a renaissance. New highly efficient and cost-effective plant concepts together with environmental protection technologies are the main factors in this development. In addition, coal is available on the world market at attractive prices and in many places it is more readily available than gas. At the economical leading edge, standard power plant concepts have been developed to meet the requirements of emerging power markets. These concepts incorporate the high technological state-of-the-art and are designed to achieve lowest life-cycle costs. Low capital cost, fuel costs and operating costs in combination withmore » shortest lead times are the main assets that make these plants attractive especially for IPPs and Developers. Other aspects of these comprehensive concepts include turnkey construction and the willingness to participate in BOO/BOT projects. One of the various examples of such a concept, the 2 x 610-MW Paiton Private Power Project Phase II in Indonesia, is described in this paper. At the technological leading edge, Siemens has always made a major contribution and was pacemaker for new developments in steam power plant technology. Modern coal-fired steam power plants use computer-optimized process and plant design as well as advanced materials, and achieve efficiencies exceeding 45%. One excellent example of this high technology is the world's largest lignite-fired steam power plant Schwarze Pumpe in Germany, which is equipped with two 800 MW Siemens steam turbine generators with supercritical steam parameters. The world's largest 50-Hz single-shaft turbine generator with supercritical steam parameters rated at 1025 MW for the Niederaussem lignite-fired steam power plant in Germany is a further example of the sophisticated Siemens steam turbine technology and sets a new benchmark in this field.« less
Mercury Emissions Capture Efficiency with Activated Carbon ...
This EPA-led project, conducted in collaboration with UNEP, the Swedish Environmental Institute and various Russian Institutes, that demonstrates that the mercury emission control efficiencies of activated carbon injection technologies applied at a Russian power plant burning Russian coals are similar to those found at U.S. plants burning US coals. (The US funding was from funds provided to the EPA by the Department of State pursuant to the Bio-Chemical Redirect Program which engages former Russian (and other former Soviet) weapons scientists in research projects with US collaborators.) Among other things, this report will aid the major task, of developing guidance on best available mercury control technology/best environmental practices (BAT/BEP) for coal-fired power plants, a major source a global anthropogenic emissions. (The new Minamata Convention requires BAT/BEP for new power plants and other major emission sources within five years of treaty ratification.)
Megawatt-Scale Application of Thermoelectric Devices in Thermal Power Plants
NASA Astrophysics Data System (ADS)
Knox, A. R.; Buckle, J.; Siviter, J.; Montecucco, A.; McCulloch, E.
2013-07-01
Despite the recent investment in renewable and sustainable energy sources, over 95% of the UK's electrical energy generation relies on the use of thermal power plants utilizing the Rankine cycle. Advanced supercritical Rankine cycle power plants typically have a steam temperature in excess of 600°C at a pressure of 290 bar and yet still have an overall efficiency below 50%, with much of this wasted energy being rejected to the environment through the condenser/cooling tower. This paper examines the opportunity for large-scale application of thermoelectric heat pumps to modify the Rankine cycle in such plants by preheating the boiler feedwater using energy recovered from the condenser system at a rate of approximately 1 MWth per °C temperature rise. A derivation of the improved process cycle efficiency and breakeven coefficient of performance required for economic operation is presented for a typical supercritical 600-MWe installation.
Facing technological challenges of Solar Updraft Power Plants
NASA Astrophysics Data System (ADS)
Lupi, F.; Borri, C.; Harte, R.; Krätzig, W. B.; Niemann, H.-J.
2015-01-01
The Solar Updraft Power Plant technology addresses a very challenging idea of combining two kinds of renewable energy: wind and solar. The working principle is simple: a Solar Updraft Power Plant (SUPP) consists of a collector area to heat the air due to the wide-banded ultra-violet solar radiation, the high-rise solar tower to updraft the heated air to the atmosphere, and in between the power conversion unit, where a system of coupled turbines and generators transforms the stream of heated air into electric power. A good efficiency of the power plant can only be reached with extra-large dimensions of the tower and/or the collector area. The paper presents an up-to-date review of the SUPP technology, focusing on the multi-physics modeling of the power plant, on the structural behavior of the tower and, last but not least, on the modeling of the stochastic wind loading process.
NASA Astrophysics Data System (ADS)
Khankari, Goutam; Karmakar, Sujit
2017-06-01
This paper proposes a comparative performance analysis based on 4-E (Energy, Exergy, Environment, and Economic) of a bottoming pure Ammonia (NH3) based Organic Rankine Cycle (ORC) and Ammonia-water (NH3-H2O) based Kalina Cycle System 11(KCS 11) for additional power generation through condenser waste heat recovery integrated with a conventional 500MWe Subcritical coal-fired thermal power plant. A typical high-ash Indian coal is used for the analysis. The flow-sheet computer programme `Cycle Tempo' is used to simulate both the cycles for thermodynamic performance analysis at different plant operating conditions. Thermodynamic analysis is done by varying different NH3 mass fraction in KCS11 and at different turbine inlet pressure in both ORC and KCS11. Results show that the optimum operating pressure of ORC and KCS11 with NH3 mass fraction of 0.90 are about 15 bar and 11.70 bar, respectively and more than 14 bar of operating pressure, the plant performance of ORC integrated power plant is higher than the KCS11 integrated power plant and the result is observed reverse below this pressure. The energy and exergy efficiencies of ORC cycle are higher than the KCS11 by about 0.903 % point and 16.605 % points, respectively under similar saturation vapour temperature at turbine inlet for both the cycles. Similarly, plant energy and exergy efficiencies of ORC based combined cycle power plant are increased by 0.460 % point and 0.420 % point, respectively over KCS11 based combined cycle power plant. Moreover, the reduction of CO2 emission in ORC based combined cycle is about 3.23 t/hr which is about 1.5 times higher than the KCS11 based combined cycle power plant. Exergy destruction of the evaporator in ORC decreases with increase in operating pressure due to decrease in temperature difference of heat exchanging fluids. Exergy destruction rate in the evaporator of ORC is higher than KCS11 when the operating pressure of ORC reduces below 14 bar. This happens due to variable boiling temperature of NH3-H2O binary mixture in KCS11 and resulting in less irreversibility during the process of heat transfer. Levelized Cost of Electricity (LCoE) generation and the cost of implementation of ORC integrated power plant is about Rs.1.767/- per kWh and Rs. 2.187/- per kg of fuel saved, respectively whereas, the LCoE for KCS11 based combined power plant is slightly less than the ORC based combined cycle power plant and estimated as about Rs.1.734 /- per kWh. The cost of implementation of KCS11 based combined cycle power plant is about Rs. 0.332/- per kg of fuel saved. Though the energy and exergy efficiencies of ORC is better than KCS11 but considering the huge investment for developing the combined cycle power plant based on ORC in comparison with KCS11 below the operating pressure of 14 bar, KCS11 is superior than NH3 based ORC.
NASA Technical Reports Server (NTRS)
Tsu, T. C.
1976-01-01
A closed-cycle MHD system for an electric power plant was studied. It consists of 3 interlocking loops, an external heating loop, a closed-cycle cesium seeded argon nonequilibrium ionization MHD loop, and a steam bottomer. A MHD duct maximum temperature of 2366 K (3800 F), a pressure of 0.939 MPa (9.27 atm) and a Mach number of 0.9 are found to give a topping cycle efficiency of 59.3%; however when combined with an integrated gasifier and optimistic steam bottomer the coal to bus bar efficiency drops to 45.5%. A 1978 K (3100 F) cycle has an efficiency of 55.1% and a power plant efficiency of 42.2%. The high cost of the external heating loop components results in a cost of electricity of 21.41 mills/MJ (77.07 mills/kWh) for the high temperature system and 19.0 mills/MJ (68.5 mills/kWh) for the lower temperature system. It is, therefore, thought that this cycle may be more applicable to internally heated systems such as some futuristic high temperature gas cooled reactor.
Hasan, Naimul; Rai, Jitendra Nath; Arora, Bharat Bhushan
2014-01-01
In the Modern scenario, the naturally available resources for power generation are being depleted at an alarming rate; firstly due to wastage of power at consumer end, secondly due to inefficiency of various power system components. A Combined Cycle Gas Turbine (CCGT) integrates two cycles- Brayton cycle (Gas Turbine) and Rankine cycle (Steam Turbine) with the objective of increasing overall plant efficiency. This is accomplished by utilising the exhaust of Gas Turbine through a waste-heat recovery boiler to run a Steam Turbine. The efficiency of a gas turbine which ranges from 28% to 33% can hence be raised to about 60% by recovering some of the low grade thermal energy from the exhaust gas for steam turbine process. This paper is a study for the modelling of CCGT and comparing it with actual operational data. The performance model for CCGT plant was developed in MATLAB/Simulink.
Mittal, Moti L; Sharma, Chhemendra; Singh, Richa
2014-10-01
This study aims to estimate the emissions of carbon dioxide (CO₂), sulfur dioxide (SO₂), and nitric oxide (NO) for coal combustion in thermal power plants in India using plant-specific emission factors during the period of 2001/02 to 2009/10. The mass emission factors have been theoretically calculated using the basic principles of combustion under representative prevailing operating conditions in the plants and fuel composition. The results show that from 2001/02 to 2009/10 period, total CO₂ emissions have increased from 324 to 499 Mt/year; SO₂ emissions have increased from 2,519 to 3,840 kt/year; and NO emissions have increased from 948 to 1,539 kt/year from the Indian coal-fired power plants. National average emissions per unit of electricity from the power plants do not show a noticeable improvement during this period. Emission efficiencies for new plants that use improved technology are found to be better than those of old plants. As per these estimates, the national average of CO₂ emissions per unit of electricity varies between 0.91 and 0.95 kg/kWh while SO₂ and NO emissions vary in the range of 6.9 to 7.3 and 2.8 to 2.9 g/kWh, respectively. Yamunagar plant in Haryana state showed the highest emission efficiencies with CO₂ emissions as 0.58 kg/kWh, SO₂ emissions as 3.87 g/kWh, and NO emissions as 1.78 g/kWh, while the Faridabad plant has the lowest emission efficiencies with CO₂ emissions as 1.5 kg/kWh, SO₂ emissions as 10.56 g/kWh, and NO emissions as 4.85 g/kWh. Emission values at other plants vary between the values of these two plants.
NASA Technical Reports Server (NTRS)
George, Jeffrey
2014-01-01
Thermionic (TI) power conversion is a promising technology first investigated for power conversion in the 1960's, and of renewed interest due to modern advances in nanotechnology, MEMS, materials and manufacturing. Benefits include high conversion efficiency (20%), static operation with no moving parts and potential for high reliability, greatly reduced plant complexity, and the potential for reduced development costs. Thermionic emission, credited to Edison in 1880, forms the basis of vacuum tubes and much of 20th century electronics. Heat can be converted into electricity when electrons emitted from a hot surface are collected across a small gap. For example, two "small" (6 kWe) Thermionic Space Reactors were flown by the USSR in 1987-88 for ocean radar reconnaissance. Higher powered Nuclear-Thermionic power systems driving Electric Propulsion (Q-thruster, VASIMR, etc.) may offer the breakthrough necessary for human Mars missions of < 1 yr round trip. Power generation on Earth could benefit from simpler, moe economical nuclear plants, and "topping" of more fuel and emission efficient fossil-fuel plants.
Importance of hard coal in electricity generation in Poland
NASA Astrophysics Data System (ADS)
Plewa, Franciszek; Strozik, Grzegorz
2017-11-01
Polish energy sector is facing a number of challenges, in particular as regards the reconstruction of production potential, diversification of energy sources, environmental issues, adequate fuels supplies and other. Mandatory implementation of Europe 2020 strategy in terms of “3x20” targets (20% reduction of greenhouse gases, 20% of energy from renewable sources, and 20% increase of efficiency in energy production) requires fast decision, which have to be coordinated with energetic safety issues, increasing demands for electric energy, and other factors. In Poland almost 80% of power is installed in coal fired power plants and energy from hard coals is relatively less expensive than from other sources, especially renewable. The most of renewable energy sources power plants are unable to generate power in amounts which can be competitive with coal fires power stations and are highly expensive, what leads o high prices of electric energy. Alternatively, new generation of coal fired coal power plants is able to significantly increase efficiency, reduce carbon dioxide emission, and generate less expensive electric power in amounts adequate to the demands of a country.
NASA Astrophysics Data System (ADS)
Gordeev, S. I.; Bogatova, T. F.; Ryzhkov, A. F.
2017-11-01
Raising the efficiency and environmental friendliness of electric power generation from coal is the aim of numerous research groups today. The traditional approach based on the steam power cycle has reached its efficiency limit, prompted by materials development and maneuverability performance. The rival approach based on the combined cycle is also drawing nearer to its efficiency limit. However, there is a reserve for efficiency increase of the integrated gasification combined cycle, which has the energy efficiency at the level of modern steam-turbine power units. The limit of increase in efficiency is the efficiency of NGCC. One of the main problems of the IGCC is higher costs of receiving and preparing fuel gas for GTU. It would be reasonable to decrease the necessary amount of fuel gas in the power unit to minimize the costs. The effect can be reached by raising of the heat value of fuel gas, its heat content and the heat content of cycle air. On the example of the process flowsheet of the IGCC with a power of 500 MW, running on Kuznetsk bituminous coal, by means of software Thermoflex, the influence of the developed technical solutions on the efficiency of the power plant is considered. It is received that rise in steam-air blast temperature to 900°C leads to an increase in conversion efficiency up to 84.2%. An increase in temperature levels of fuel gas clean-up to 900°C leads to an increase in the IGCC efficiency gross/net by 3.42%. Cycle air heating reduces the need for fuel gas by 40% and raises the IGCC efficiency gross/net by 0.85-1.22%. The offered solutions for IGCC allow to exceed net efficiency of analogous plants by 1.8-2.3%.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Dan Wendt; Greg Mines
2014-09-01
Many, if not all, geothermal resources are subject to decreasing productivity manifested in the form of decreasing brine temperature, flow rate, or both during the life span of the associated power generation project. The impacts of resource productivity decline on power plant performance can be significant; a reduction in heat input to a power plant not only decreases the thermal energy available for conversion to electrical power, but also adversely impacts the power plant conversion efficiency. The reduction in power generation is directly correlated to a reduction in revenues from power sales. Further, projects with Power Purchase Agreement (PPA) contractsmore » in place may be subject to significant economic penalties if power generation falls below the default level specified. A potential solution to restoring the performance of a power plant operating from a declining productivity geothermal resource involves the use of solar thermal energy to restore the thermal input to the geothermal power plant. There are numerous technical merits associated with a renewable geothermal-solar hybrid plant in which the two heat sources share a common power block. The geo-solar hybrid plant could provide a better match to typical electrical power demand profiles than a stand-alone geothermal plant. The hybrid plant could also eliminate the stand-alone concentrated solar power plant thermal storage requirement for operation during times of low or no solar insolation. This paper identifies hybrid plant configurations and economic conditions for which solar thermal retrofit of a geothermal power plant could improve project economics. The net present value of the concentrated solar thermal retrofit of an air-cooled binary geothermal plant is presented as functions of both solar collector array cost and electricity sales price.« less
NASA Astrophysics Data System (ADS)
Teplov, B. D.; Radin, Yu. A.; Filin, A. A.; Rudenko, D. V.
2016-08-01
In December 2014, the PGU-420T power-generating unit was put into operation at the Combined Heat and Power Plant 16, an affiliated company of PAO Mosenergo. In 2014-2015, thermal tests of the SGT5- 4000F gas-turbine plant (GTP) integrated into the power-generating unit were carried out. In the article, the test conditions are described and the test results are presented and analyzed. During the tests, 92 operating modes within a wide range of electrical loads and ambient air temperatures and operating conditions of the GTP when fired with fuel oil were investigated. In the tests, an authorized automated measuring system was applied. The experimental data were processed according to ISO 2314:2009 "Gas turbines—Acceptance tests" standard. The available capacity and the GTP efficiency vary from 266 MW and 38.8% to 302 MW and 39.8%, respectively, within the ambient air temperature range from +24 to-12°C, while the turbine inlet temperature decreases from 1200 to 1250°C. The switch to firing fuel oil results in a reduction in the turbine inlet temperature and the capacity of the GTP. With the full load and a reduction in the ambient temperature from +24 to-12°C, the compressor efficiency decreases from 89.6 to 86.4%. The turbine efficiency is approximately 89-91%. Within the investigated range of power output, the emissions of nitrogen oxides do not exceed 35 ppm for the gas-fired plant and 65 ppm for the fuel-oil-fired plant. Within the range of the GTP power output from 50 to 100% of the rated output, the combustion chamber operates without underburning and with hardly any CO being formed. At low loads close to the no-load operation mode, the CO emissions drastically increase.
NASA Astrophysics Data System (ADS)
Giri Babu, P. V. S.; Swaminathan, G.
2016-09-01
A comprehensive study was carried out on four different fly ashes used as a catalyst for the degradation of Acid Red 1 using ultraviolet rays. These fly ashes are collected from different thermal power stations located at various places in India and having different chemical compositions. Three fly ashes are from lignite-based thermal power plants, and one is from the coal-based power plant. One fly ash is classified as Class F, two fly ashes are classified as Class C and remaining one is not conforming to ASTM C618 classification. X-Ray Fluorescence analysis was used to identify the chemical composition of fly ashes and SiO2, Al2O3, CaO, Fe2O3 and TiO2 were found to be the major elements present in different proportions. Various analysis were carried out on all the fly ashes like Scanning Electron Microscopy to identify the microphysical properties, Energy Dispersive X-Ray spectroscopy to quantify the elements present in the catalyst and X-Ray Diffraction to identify the catalyst phase analysis. The radical generated during the reaction was identified by Electron paramagnetic resonance spectroscopy. The parameters such as initial pH of the dye solution, catalyst dosage and initial dye concentration which influence the dye degradation efficiency were studied and optimised. In 60 min duration, the dye degradation efficiency at optimum parametric values of pH 2.5, initial dye concentration of 10 mg/L and catalyst dosage of 1.0 g/L using various fly ashes, i.e., Salam Power Plant, Barmer Lignite Power Plant, Kutch Lignite Power Plant and Neyveli Lignite Thermal Power plant (NLTP) were found to be 40, 60, 67 and 95 % respectively. The contribution of adsorption alone was 18 % at the above mentioned optimum parametric values. Among the above four fly ash NLTP fly ashes proved to be most efficient.
A parametric simulation of solar chimney power plant
NASA Astrophysics Data System (ADS)
Beng Hooi, Lim; Kannan Thangavelu, Saravana
2018-01-01
The strong solar radiation, continuous supplies of sunlight and environmental friendly factors have made the solar chimney power plant becoming highly feasible to build in Malaysia. Solar chimney power plant produces upward buoyancy force through the greenhouse effect. Numerical simulation was performed on the model of a solar chimney power plant using the ANSYS Fluent software by applying standard k-epsilon turbulence model and discrete ordinates (DO) radiation model to solve the relevant equations. A parametric study was carried out to evaluate the performance of solar chimney power plant, which focused on the temperature rise in the collector, air velocity at the chimney base, and pressure drop inside the chimney were based on the results of temperature, velocity, and static pressure distributions. The results demonstrate reliability by comparing a model with the experimental data of Manzanares Spanish prototype. Based on the numerical results, power capacity and efficiency were analysed theoretically. Results indicate that a stronger solar radiation and larger prototype will improve the performance of solar chimney power plant.
An experimental aluminum-fueled power plant
NASA Astrophysics Data System (ADS)
Vlaskin, M. S.; Shkolnikov, E. I.; Bersh, A. V.; Zhuk, A. Z.; Lisicyn, A. V.; Sorokovikov, A. I.; Pankina, Yu. V.
2011-10-01
An experimental co-generation power plant (CGPP-10) using aluminum micron powder (with average particle size up to 70 μm) as primary fuel and water as primary oxidant was developed and tested. Power plant can work in autonomous (unconnected from industrial network) nonstop regime producing hydrogen, electrical energy and heat. One of the key components of experimental plant is aluminum-water high-pressure reactor projected for hydrogen production rate of ∼10 nm3 h-1. Hydrogen from the reactor goes through condenser and dehumidifier and with -25 °C dew-point temperature enters into the air-hydrogen fuel cell 16 kW-battery. From 1 kg of aluminum the experimental plant produces 1 kWh of electrical energy and 5-7 kWh of heat. Power consumer gets about 10 kW of electrical power. Plant electrical and total efficiencies are 12% and 72%, respectively.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Jacques V Hugo
This book chapter describes the considerations for the selection of advanced human–system interfaces (HSIs) for the new generation of nuclear power plants. The chapter discusses the technologies that will be needed to support highly automated nuclear power plants, while minimising demands for numbers of operational staff, reducing human error and improving plant efficiency and safety. Special attention is paid to the selection and deployment of advanced technologies in nuclear power plants (NPPs). The chapter closes with an examination of how technologies are likely to develop over the next 10–15 years and how this will affect design choices for the nuclearmore » industry.« less
Bechara, Rami; Gomez, Adrien; Saint-Antonin, Valérie; Schweitzer, Jean-Marc; Maréchal, François
2016-08-01
The application of methodologies for the optimal design of integrated processes has seen increased interest in literature. This article builds on previous works and applies a systematic methodology to an integrated first and second generation ethanol production plant with power cogeneration. The methodology breaks into process simulation, heat integration, thermo-economic evaluation, exergy efficiency vs. capital costs, multi-variable, evolutionary optimization, and process selection via profitability maximization. Optimization generated Pareto solutions with exergy efficiency ranging between 39.2% and 44.4% and capital costs from 210M$ to 390M$. The Net Present Value was positive for only two scenarios and for low efficiency, low hydrolysis points. The minimum cellulosic ethanol selling price was sought to obtain a maximum NPV of zero for high efficiency, high hydrolysis alternatives. The obtained optimal configuration presented maximum exergy efficiency, hydrolyzed bagasse fraction, capital costs and ethanol production rate, and minimum cooling water consumption and power production rate. Copyright © 2016 Elsevier Ltd. All rights reserved.
Conceptual design study of potential early commercial MHD powerplant. Report of task 2 results
NASA Astrophysics Data System (ADS)
Hals, F. A.
1981-03-01
The conceptual design of one of the potential early commercial MHD power plants was studied. The plant employs oxygen enrichment of the combustion air and preheating of this oxygen enriched air to an intermediate temperature of 1200 F attainable with a tubular type recuperative heat exchanger. Conceptual designs of plant componets and equipment with performance, operational characteristics, and costs are reported. Plant economics and overall performance including full and part load operation are reviewed. The projected performance and estimated cost of this early MHD plant are compared to conventional power plants, although it does not offer the same high efficiency and low costs as the mature MHD power plant. Environmental aspects and the methods incorporated in plant design for emission control of sulfur and nitrogen are reviewed.
Conceptual design study of potential early commercial MHD powerplant. Report of task 2 results
NASA Technical Reports Server (NTRS)
Hals, F. A.
1981-01-01
The conceptual design of one of the potential early commercial MHD power plants was studied. The plant employs oxygen enrichment of the combustion air and preheating of this oxygen enriched air to an intermediate temperature of 1200 F attainable with a tubular type recuperative heat exchanger. Conceptual designs of plant componets and equipment with performance, operational characteristics, and costs are reported. Plant economics and overall performance including full and part load operation are reviewed. The projected performance and estimated cost of this early MHD plant are compared to conventional power plants, although it does not offer the same high efficiency and low costs as the mature MHD power plant. Environmental aspects and the methods incorporated in plant design for emission control of sulfur and nitrogen are reviewed.
Methods of increasing thermal efficiency of steam and gas turbine plants
NASA Astrophysics Data System (ADS)
Vasserman, A. A.; Shutenko, M. A.
2017-11-01
Three new methods of increasing efficiency of turbine power plants are described. Increasing average temperature of heat supply in steam turbine plant by mixing steam after overheaters with products of combustion of natural gas in the oxygen. Development of this idea consists in maintaining steam temperature on the major part of expansion in the turbine at level, close to initial temperature. Increasing efficiency of gas turbine plant by way of regenerative heating of the air by gas after its expansion in high pressure turbine and before expansion in the low pressure turbine. Due to this temperature of air, entering combustion chamber, is increased and average temperature of heat supply is consequently increased. At the same time average temperature of heat removal is decreased. Increasing efficiency of combined cycle power plant by avoiding of heat transfer from gas to wet steam and transferring heat from gas to water and superheated steam only. Steam will be generated by multi stage throttling of the water from supercritical pressure and temperature close to critical, to the pressure slightly higher than condensation pressure. Throttling of the water and separation of the wet steam on saturated water and steam does not require complicated technical devices.
Feasibility survey of thermoelectric conversion technology using semiconductors
NASA Astrophysics Data System (ADS)
1993-03-01
The paper takes notice to thermoelectric conversion technology using semiconductors and investigates it in a wide range from high temperature to low temperature to study its feasibility. It is found that in Bi-Te alloy elements applicable to a temperature range of around 200(degree)C, some are over 3.5(times)10(sup -3)K(sup -1) in performance index, and performance of the element can be practically improved in the near future. The thermoelectric power generation system using waste heat from the fuel cell power plant, which is 5-6% in conversion efficiency, can generate output more than 100kW and is expected to improve by approximately 1% in plant overall efficiency. The construction cost, however, is around 1.6-1.9 million yen/kW. The thermoelectric power generation plant which is modeled on No.2 generator of Hatchobaru geothermal power plant can generate electric output of 10-12.5MW, which is smaller than that of the conventional geothermal power generation. The construction cost is around 3.2-4.1 million yen/kW. Even if advantage of the system in running cost is considered, attractive systematization seems to be difficult.
High Efficiency Nuclear Power Plants using Liquid Fluoride Thorium Reactor Technology
NASA Technical Reports Server (NTRS)
Juhasz, Albert J.; Rarick, Richard A.; Rangarajan, Rajmohan
2009-01-01
An overall system analysis approach is used to propose potential conceptual designs of advanced terrestrial nuclear power plants based on Oak Ridge National Laboratory (ORNL) Molten Salt Reactor (MSR) experience and utilizing Closed Cycle Gas Turbine (CCGT) thermal-to-electric energy conversion technology. In particular conceptual designs for an advanced 1 GWe power plant with turbine reheat and compressor intercooling at a 950 K turbine inlet temperature (TIT), as well as near term 100 MWe demonstration plants with TITS of 950 K and 1200 K are presented. Power plant performance data were obtained for TITS ranging from 650 to 1300 K by use of a Closed Brayton Cycle (CBC) systems code which considered the interaction between major sub-systems, including the Liquid Fluoride Thorium Reactor (LFTR), heat source and heat sink heat exchangers, turbo -generator machinery, and an electric power generation and transmission system. Optional off-shore submarine installation of the power plant is a major consideration.
NASA Astrophysics Data System (ADS)
Bellerive, Nathalie
The research project hypothesis is that CO2 capture and sequestration technologies (CSC) leads to a significant decrease in global warming, but increases the impact of all other aspects of the study. This is because other processes used for CO2 capture and sequestration require additional quantities of raw materials and energy. Two other objectives are described in this project. The first is the modeling of an Integrated Gasification Combined Cycle power plant for which there is no known generic data. The second is to select the right hypothesis regarding electrical production technologies, CO2 capture, compression and transportation by pipeline and finally sequestration. "Life Cycle Assessment" (LCA) analyses were chosen for this research project. LCA is an exhaustive quantitative method used to evaluate potential environmental impacts associated with a product, a service or an activity from resource extraction to waste elimination. This tool is governed by ISO 14 040 through ISO 14 049 and is sustained by the Society of Environmental Toxicology and Chemistry (SETAC) and the United Nations Environment Program (UNEP). Two power plants were studied, the Integrated Gasification Combined Cycle (IGCC) power plant and the Natural Gas Combined Cycle (NGCC) power plant. In order to sequester CO2 in geological formation, it is necessary to extract CO2from emission flows. For the IGCC power plant, CO 2 was captured before the burning phase. For the NGCC power plant, the capture was done during the afterburning phase. Once the CO2 was isolated, it was compressed and directed through a transportation pipe 1 000 km in length on the ground surface and in the sea. It is hypothesized that the power plant is 300 km from the shore and the sequestration platform 700 km from France's shore, in the North Sea. The IGCC power plant modeling and data selection regarding CO2 capture and sequestration were done by using primary data from the industry and the Ecoinvent generic database (Version 1.2). This database was selected due to its European source. Finally, technical calculations and literature were used to complete the data inventory. This was validated by electrical experts in order to increase data and modeling precision. Results were similar for IGCC and NGCC power plants using Impact 2002+, an impacts analysis method. Global warming potential decreased by 67% with the implementation of CO2 capture and sequestration compared to systems without CSC. Results for all others impacts categories, demonstrated an increase from 16% to 116% in relative proportions compared to systems without CSC. The main contributor was the additional quantity of energy required to operate CO2 capture and compression facilities. This additional energy negatively affected the power plant's global efficiency because of the increase in the quantity of fossil fuel that needed to be extracted and consumed. The increase in other impacts was mainly due to additional electricity, fossil fuel (for extracting, treatment and transportation) and additional emissions generated during power plant operations. A scenario analysis was done to study the sensitivity and variability of uncertain data during the software modeling process of a power plant. Data on power plant efficiency is the most variable and sensitive during modeling, followed by the length of the transportation pipe and the leaking rate during CO2 sequestration. This result analysis is interesting because it led to the maximum efficiency scenario with capture (with a short CO 2 transportation distance and a low leaking rate) obtaining better results on all impact category indicators, compared to the minimum efficiency scenario without capture. In fact, positive results on all category indicators were possible during the system comparison between the two cases (with and without capture). (Abstract shortened by UMI.)
NASA Astrophysics Data System (ADS)
Orosz, Matthew; Zweibaum, Nicolas; Lance, Tamir; Ruiz, Maritza; Morad, Ratson
2016-05-01
Sunlight to electricity efficiencies of Parabolic Trough Collector (PTC) plants are typically on the order of 15%, while commercial solar Photovoltaic (PV) technologies routinely achieve efficiencies of greater than 20%, albeit with much higher conversion efficiencies of photons at the band gap. Hybridizing concentrating solar power and photovoltaic technologies can lead to higher aggregate efficiencies due to the matching of photons to the appropriate converter based on wavelength. This can be accomplished through spectral filtering whereby photons unusable or poorly utilitized by PV (IR and UV) are passed through to a heat collection element, while useful photons (VIS) are reflected onto a concentrating PV (CPV) receiver. The mechanical design and experimental validation of spectral splitting optics is described in conjunction with system level modeling and economic analysis. The implications of this architecture include higher efficiency, lower cost hybrid CSP-PV power systems, as well as the potential to retrofit existing PTC plants to boost their output by ~ 10% at a projected investment cost of less than 1 per additional net Watt and an IRR of 18%, while preserving the dispatchability of the CSP plant's thermal energy storage.
Silica problem in the design of geothermal power plants
NASA Astrophysics Data System (ADS)
Dipippo, R.
1985-02-01
The silica problem is examined from the perspective of the power plant designer to develop a procedure to enable a quick estimate to be made of the potential seriousness of the silica deposition problem for a wide variety of resources and for selected types of power plant. The method employs correlations for the equilibrium solubilities of quartz and amorphous silica and for the saturated liquid enthalpy and the latent heat of water substance. Single- and double-flash plants optimized for highest thermodynamic efficiency are considered. Binary-type plants are included generically without mention of cycle specifics. The results are presented both graphically and in tabular form, and the governing equations will be given in an easily-programmable form.
DoD Installation Energy Security: Evolving to a Smart Grid
2012-03-20
located at the Naval Air Weapons Station in China Lake, California. This series of geothermal power plants produces a peak power output of 270 megawatts...initiatives are driving the DoD to invest significantly in renewable energy resources like solar, wind, and geothermal , as well as energy efficient vehicles...hydroelectric, geothermal ) resources. The most common and largest forms of electrical generation come from power plants that use fossil fuels
Near-Blackbody Enclosed Particle-Receiver Development
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ma, Zhiwen; Sakadjian, Bartev
2015-12-01
This 3-year project develops a technology using gas/solid, two-phase flow as a heat-transfer fluid and separated, stable, solid particles as a thermal energy storage (TES) medium for a concentrating solar power (CSP) plant, to address the temperature, efficiency, and cost barriers associated with current molten-salt CSP systems. This project focused on developing a near-blackbody particle receiver and an integrated fluidized-bed heat exchanger with auxiliary components to achieve greater than 20% cost reduction over current CSP plants, and to provide the ability to drive high-efficiency power cycles.
NASA Technical Reports Server (NTRS)
Warde, C. J.; Ruka, R. J.; Isenberg, A. O.
1976-01-01
A parametric assessment of four fuel cell power systems -- based on phosphoric acid, potassium hydroxide, molten carbonate, and stabilized zirconia -- has shown that the most important parameters for electricity-cost reduction and/or efficiency improvement standpoints are fuel cell useful life and power density, use of a waste-heat recovery system, and fuel type. Typical capital costs, overall energy efficiencies (based on the heating value of the coal used to produce the power plant fuel), and electricity costs are: phosphoric acid $350-450/kWe, 24-29%, and 11.7 to 13.9 mills/MJ (42 to 50 mills/kWh); alkaline $450-700/kWe, 26-31%, and 12.8 to 16.9 mills/MJ (46 to 61 mills/kWh); molten carbonate $480-650/kWe, 32-46%, and 10.6 to 19.4 mills/MJ (38 to 70 mills/kWh), stabilized zirconia $420-950/kWe, 26-53%, and 9.7 to 16.9 mills/MJ (35 to 61 mills/kWh). Three types of fuel cell power plants -- solid electrolytic with steam bottoming, molten carbonate with steam bottoming, and solid electrolyte with an integrated coal gasifier -- are recommended for further study.
Field-Reversed Configuration Power Plant Critical-Issue Scoping Study
DOE Office of Scientific and Technical Information (OSTI.GOV)
Santarius, J. F.; Mogahed, E. A.; Emmert, G. A.
A team from the Universities of Wisconsin, Washington, and Illinois performed an engineering scoping study of critical issues for field-reversed configuration (FRC) power plants. The key tasks for this research were (1) systems analysis for deuterium-tritium (D-T) FRC fusion power plants, and (2) conceptual design of the blanket and shield module for an FRC fusion core. For the engineering conceptual design of the fusion core, the project team focused on intermediate-term technology. For example, one decision was to use steele structure. The FRC systems analysis led to a fusion power plant with attractive features including modest size, cylindrical symmetry, goodmore » thermal efficiency (52%), relatively easy maintenance, and a high ratio of electric power to fusion core mass, indicating that it would have favorable economics.« less
GEOTHERMAL / SOLAR HYBRID DESIGNS: USE OF GEOTHERMAL ENERGY FOR CSP FEEDWATER HEATING
DOE Office of Scientific and Technical Information (OSTI.GOV)
Craig Turchi; Guangdong Zhu; Michael Wagner
2014-10-01
This paper examines a hybrid geothermal / solar thermal plant design that uses geothermal energy to provide feedwater heating in a conventional steam-Rankine power cycle deployed by a concentrating solar power (CSP) plant. The geothermal energy represents slightly over 10% of the total thermal input to the hybrid plant. The geothermal energy allows power output from the hybrid plant to increase by about 8% relative to a stand-alone CSP plant with the same solar-thermal input. Geothermal energy is converted to electricity at an efficiency of 1.7 to 2.5 times greater than would occur in a stand-alone, binary-cycle geothermal plant usingmore » the same geothermal resource. While the design exhibits a clear advantage during hybrid plant operation, the annual advantage of the hybrid versus two stand-alone power plants depends on the total annual operating hours of the hybrid plant. The annual results in this draft paper are preliminary, and further results are expected prior to submission of a final paper.« less
Conceptual design of the DEMO neutral beam injectors: main developments and R&D achievements
NASA Astrophysics Data System (ADS)
Sonato, P.; Agostinetti, P.; Bolzonella, T.; Cismondi, F.; Fantz, U.; Fassina, A.; Franke, T.; Furno, I.; Hopf, C.; Jenkins, I.; Sartori, E.; Tran, M. Q.; Varje, J.; Vincenzi, P.; Zanotto, L.
2017-05-01
The objectives of the nuclear fusion power plant DEMO, to be built after the ITER experimental reactor, are usually understood to lie somewhere between those of ITER and a ‘first of a kind’ commercial plant. Hence, in DEMO the issues related to efficiency and RAMI (reliability, availability, maintainability and inspectability) are among the most important drivers for the design, as the cost of the electricity produced by this power plant will strongly depend on these aspects. In the framework of the EUROfusion Work Package Heating and Current Drive within the Power Plant Physics and Development activities, a conceptual design of the neutral beam injector (NBI) for the DEMO fusion reactor has been developed by Consorzio RFX in collaboration with other European research institutes. In order to improve efficiency and RAMI aspects, several innovative solutions have been introduced in comparison to the ITER NBI, mainly regarding the beam source, neutralizer and vacuum pumping systems.
Method and apparatus for improving the performance of a nuclear power electrical generation system
Tsiklauri, Georgi V.; Durst, Bruce M.
1995-01-01
A method and apparatus for improving the efficiency and performance a of nuclear electrical generation system that comprises the addition of steam handling equipment to an existing plant that results in a surprising increase in plant performance. More particularly, a gas turbine electrical generation system with heat recovery boiler is installed along with a high pressure and a low pressure mixer superheater. Depending upon plant characteristics, the existing moisture separator reheater (MSR) can be either augmented or done away with. The instant invention enables a reduction in T.sub.hot without a derating of the reactor unit, and improves efficiency of the plant's electrical conversion cycle. Coupled with this advantage is a possible extension of the plant's fuel cycle length due to an increased electrical conversion efficiency. The reduction in T.sub.hot further allows for a surprising extension of steam generator life. An additional advantage is the reduction in erosion/corrosion of secondary system components including turbine blades and diaphragms. The gas turbine generator used in the instant invention can also replace or augment existing peak or emergency power needs.
Energy conversion/power plant cost-cutting
DOE Office of Scientific and Technical Information (OSTI.GOV)
Nichols, K.
This presentation by Kenneth Nichols, Barber-Nichols, Inc., is about cost-cutting in the energy conversion phase and power plant phase of geothermal energy production. Mr. Nichols discusses several ways in which improvements could be made, including: use of more efficient compressors and other equipment as they become available, anticipating reservoir resource decline and planning for it, running smaller binary systems independent of human operators, and designing plants so that they are relatively maintenance-free.
76 FR 20320 - Renewable Energy and Energy Efficiency Executive Business Development Mission
Federal Register 2010, 2011, 2012, 2013, 2014
2011-04-12
... 20,000 MW of wind energy and 600 MW of geothermal energy capacity by 2023 (100th year anniversary of... power farms, 300 MW geothermal power plants come into operation by 2015. As part of the energy... DEPARTMENT OF COMMERCE International Trade Administration Renewable Energy and Energy Efficiency...
Coal mine burns drainage gas to generate power for profit
DOE Office of Scientific and Technical Information (OSTI.GOV)
Scholes, W.A.
A recently commissioned gas turbine power plant that uses methane gas recovered from a coal mine is described. The power plant uses the ASEA Stal GT35B series gas turbines with a base load rating on gas of 12.9 MW at 29.3% efficiency. The plant was installed at a cost of $4 million, as part of an extensive system for removing the methane from the coal mine, enabling higher ratio of coal production to be achieved in safety with modern longwall mining techniques. The plant will save the mine up to $250,000 per month on its electricity bill plus generate profitmore » from the sale of surplus power to the local activity.« less
NASA Astrophysics Data System (ADS)
Tomarov, G. V.; Shipkov, A. A.
2011-03-01
The main stages and processes through which deposits are generated, migrate, and precipitate in the metal-secondary coolant system of power units at nuclear power plants are analyzed and determined. It is shown that substances produced by the mechanism of general erosion-corrosion are the main source of the ionic-colloid form of iron, which is the main component of deposits in a steam generator. Ways for controlling the formation of deposits in a nuclear power plant's steam generator are proposed together with methods for estimating their efficiency.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Elcock, D.
2010-09-17
This report was funded by the U.S. Department of Energy's (DOE's) National Energy Technology Laboratory (NETL) Existing Plants Research Program, which has an energy-water research effort that focuses on water use at power plants. This study complements the overall research effort of the Existing Plants Research Program by evaluating water issues that could impact power plants. A growing challenge to the economic production of electricity from coal-fired power plants is the demand for freshwater, particularly in light of the projected trends for increasing demands and decreasing supplies of freshwater. Nanotechnology uses the unique chemical, physical, and biological properties that aremore » associated with materials at the nanoscale to create and use materials, devices, and systems with new functions and properties. It is possible that nanotechnology may open the door to a variety of potentially interesting ways to reduce freshwater consumption at power plants. This report provides an overview of how applications of nanotechnology could potentially help reduce freshwater use at coal-fired power plants. It was developed by (1) identifying areas within a coal-fired power plant's operations where freshwater use occurs and could possibly be reduced, (2) conducting a literature review to identify potential applications of nanotechnology for facilitating such reductions, and (3) collecting additional information on potential applications from researchers and companies to clarify or expand on information obtained from the literature. Opportunities, areas, and processes for reducing freshwater use in coal-fired power plants considered in this report include the use of nontraditional waters in process and cooling water systems, carbon capture alternatives, more efficient processes for removing sulfur dioxide and nitrogen oxides, coolants that have higher thermal conductivities than water alone, energy storage options, and a variety of plant inefficiencies, which, if improved, would reduce energy use and concomitant water consumption. These inefficiencies include air heater inefficiencies, boiler corrosion, low operating temperatures, fuel inefficiencies, and older components that are subject to strain and failure. A variety of nanotechnology applications that could potentially be used to reduce the amount of freshwater consumed - either directly or indirectly - by these areas and activities was identified. These applications include membranes that use nanotechnology or contain nanomaterials for improved water purification and carbon capture; nano-based coatings and lubricants to insulate and reduce heat loss, inhibit corrosion, and improve fuel efficiency; nano-based catalysts and enzymes that improve fuel efficiency and improve sulfur removal efficiency; nanomaterials that can withstand high temperatures; nanofluids that have better heat transfer characteristics than water; nanosensors that can help identify strain and impact damage, detect and monitor water quality parameters, and measure mercury in flue gas; and batteries and capacitors that use nanotechnology to enable utility-scale storage. Most of these potential applications are in the research stage, and few have been deployed at coal-fired power plants. Moving from research to deployment in today's economic environment will be facilitated with federal support. Additional support for research development and deployment (RD&D) for some subset of these applications could lead to reductions in water consumption and could provide lessons learned that could be applied to future efforts. To take advantage of this situation, it is recommended that NETL pursue funding for further research, development, or deployment for one or more of the potential applications identified in this report.« less
NASA Astrophysics Data System (ADS)
Indra Siswantara, Ahmad; Pujowidodo, Hariyotejo; Darius, Asyari; Ramdlan Gunadi, Gun Gun
2018-03-01
This paper presents the mathematical modeling analysis on cooling system in a combined cycle power plant. The objective of this study is to get the impact of cooling water upsurge on plant performance and operation, using Engineering Equation Solver (EES™) tools. Power plant installed with total power capacity of block#1 is 505.95 MWe and block#2 is 720.8 MWe, where sea water consumed as cooling media at two unit condensers. Basic principle of analysis is heat balance calculation from steam turbine and condenser, concern to vacuum condition and heat rate values. Based on the result shown graphically, there were impact the upsurge of cooling water to increase plant heat rate and vacuum pressure in condenser so ensued decreasing plant efficiency and causing possibility steam turbine trip as back pressure raised from condenser.
Ice Thermal Storage Systems for LWR Supplemental Cooling and Peak Power Shifting
DOE Office of Scientific and Technical Information (OSTI.GOV)
Haihua Zhao; Hongbin Zhang; Phil Sharpe
2010-06-01
Availability of enough cooling water has been one of the major issues for the nuclear power plant site selection. Cooling water issues have frequently disrupted the normal operation at some nuclear power plants during heat waves and long draught. The issues become more severe due to the new round of nuclear power expansion and global warming. During hot summer days, cooling water leaving a power plant may become too hot to threaten aquatic life so that environmental regulations may force the plant to reduce power output or even temporarily to be shutdown. For new nuclear power plants to be builtmore » at areas without enough cooling water, dry cooling can be used to remove waste heat directly into the atmosphere. However, dry cooling will result in much lower thermal efficiency when the weather is hot. One potential solution for the above mentioned issues is to use ice thermal storage systems (ITS) that reduce cooling water requirements and boost the plant’s thermal efficiency in hot hours. ITS uses cheap off-peak electricity to make ice and uses those ice for supplemental cooling during peak demand time. ITS is suitable for supplemental cooling storage due to its very high energy storage density. ITS also provides a way to shift large amount of electricity from off peak time to peak time. Some gas turbine plants already use ITS to increase thermal efficiency during peak hours in summer. ITSs have also been widely used for building cooling to save energy cost. Among three cooling methods for LWR applications: once-through, wet cooling tower, and dry cooling tower, once-through cooling plants near a large water body like an ocean or a large lake and wet cooling plants can maintain the designed turbine backpressure (or condensation temperature) during 99% of the time; therefore, adding ITS to those plants will not generate large benefits. For once-through cooling plants near a limited water body like a river or a small lake, adding ITS can bring significant economic benefits and avoid forced derating and shutdown during extremely hot weather. For the new plants using dry cooling towers, adding the ice thermal storage systems can effectively reduce the efficiency loss and water consumption during hot weather so that new LWRs could be considered in regions without enough cooling water. \\ This paper presents the feasibility study of using ice thermal storage systems for LWR supplemental cooling and peak power shifting. LWR cooling issues and ITS application status will be reviewed. Two ITS application case studies will be presented and compared with alternative options: one for once-through cooling without enough cooling for short time, and the other with dry cooling. Because capital cost, especially the ice storage structure/building cost, is the major cost for ITS, two different cost estimation models are developed: one based on scaling method, and the other based on a preliminary design using Building Information Modeling (BIM), an emerging technology in Architecture/Engineering/Construction, which enables design options, performance analysis and cost estimating in the early design stage.« less
NASA Astrophysics Data System (ADS)
Kasilov, V. F.; Dudolin, A. A.; Gospodchenkov, I. V.
2015-05-01
The design of a modular SVBR-100 reactor with a lead-bismuth alloy liquid-metal coolant is described. The basic thermal circuit of a power unit built around the SVBR-100 reactor is presented together with the results of its calculation. The gross electrical efficiency of the turbine unit driven by saturated steam at a pressure of 6.7 MPa is estimated at η{el/gr} = 35.5%. Ways for improving the efficiency of this power unit and increasing its power output by applying gas-turbine and combined-cycle technologies are considered. With implementing a combined-cycle power-generating system comprising two GE-6101FA gas-turbine units with a total capacity of 140 MW, it becomes possible to obtain the efficiency of the combined-cycle plant equipped with the SVBR-100 reactor η{el/gr} = 45.39% and its electrical power output equal to 328 MW. The heat-recovery boiler used as part of this power installation generates superheated steam with a temperature of 560°C, due to which there is no need to use a moisture separator/steam reheater in the turbine unit thermal circuit.
NASA Astrophysics Data System (ADS)
Douvartzides, S.; Karmalis, I.
2016-11-01
Organic Rankine cycle technology is capable to efficiently convert low-grade heat into useful mechanical power. In the present investigation such a cycle is used for the recovery of heat from the exhaust gases of a four stroke V18 MAN 51/60DF internal combustion engine power plant operating with natural gas. Design is focused on the selection of the appropriate working fluid of the Rankine cycle in terms of thermodynamic, environmental and safety criteria. 37 candidate fluids have been considered and all Rankine cycles examined were subcritical. The thermodynamic analysis of all fluids has been comparatively undertaken and the effect of key operation conditions such as the evaporation pressure and the superheating temperature was taken into account. By appropriately selecting the working fluid and the Rankine cycle operation conditions the overall plant efficiency was improved by 5.52% and fuel consumption was reduced by 12.69%.
NASA Astrophysics Data System (ADS)
Lekube, J.; Garrido, A. J.; Garrido, I.
2018-03-01
The effects of climate change and global warming reveal the need to find alternative sources of clean energy. In this sense, wave energy power plants, and in particular Oscillating Water Column (OWC) devices, offer a huge potential of energy harnessing. Nevertheless, the conversion systems have not reached a commercially mature stage yet so as to compete with conventional power plants. At this point, the use of new control methods over the existing technology arises as a doable way to improve the efficiency of the system. Due to the non-uniform response that the turbine shows to the rotational speed variation, the speed control of the turbo-generator may offer a feasible solution for efficiency improvement during the energy conversion. In this context, a novel speed control approach for OWC systems is presented in this paper, demonstrating its goodness and affording promising results when particularized to the Mutriku’s wave power plant.
The World Bank’s Clean Technology Fund (CTF)
2008-11-24
economies such as China and India. The incremental carbon dioxide (CO2) emissions from China and India alone have accounted for an estimated 62% of new...gas reductions. Carbon dioxide emissions from power plants are directly proportional to efficiency, so a plant going with an 18% absolute increase in...efficiency would produce 18% less carbon dioxide . These are the higher heating value (HHV) thermal efficiency rates, not be confused with lower heating
The study of integrated coal-gasifier molten carbonate fuel cell systems
NASA Technical Reports Server (NTRS)
1983-01-01
A novel integration concept for a coal-fueled coal gasifier-molten carbonate fuel cell power plant was studied. Effort focused on determining the efficiency potential of the concept, design, and development requirements of the processes in order to achieve the efficiency. The concept incorporates a methane producing catalytic gasifier of the type previously under development by Exxon Research and Development Corp., a reforming molten carbonate fuel cell power section of the type currently under development by United Technologies Corp., and a gasifier-fuel cell recycle loop. The concept utilizes the fuel cell waste heat, in the form of hydrogen and carbon monoxide, to generate additional fuel in the coal gasifier, thereby eliminating the use of both an O2 plant and a stream bottoming cycle from the power plant. The concept has the potential for achieving coal-pile-to-busbar efficiencies of 50-59%, depending on the process configuration and degree of process configuration and degree of process development requirements. This is significantly higher than any previously reported gasifier-molten carbonate fuel cell system.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Torrens, I.M.; Stenzel, W.C.
Independent power producers will build a substantial fraction of expected new coal-fired power generation in developing countries over the coming decades. To reduce perceived risk and obtain financing for their projects, they are currently building and plan to continue to build subcritical coal-fired plants with generating efficiency below 40%. Up-to-date engineering assessment leads to the conclusion that supercritical generating technology, capable of efficiencies of up to 45%, can produce electricity at a lower total cost than conventional plants. If such plants were built in Asia over the coming decades, the savings in carbon dioxide emissions over their lifetime would bemore » measured in billions of tons. IPPs perceive supercritical technology as riskier and higher cost than conventional technology. The truth needs to be confirmed by discussions with additional experienced power engineering companies. Better communication among the interested parties could help to overcome the IPP perception issue. Governments working together with industry might be able to identify creative financing arrangements which can encourage the use of more efficient pulverized clean coal technologies, while awaiting the commercialization of advanced clean coal technologies like gasification combined cycle and pressurized fluidized bed combustion.« less
NASA Astrophysics Data System (ADS)
Varlamov, Gennadii Borysovich; Romanova, Kateryna Alexandrovna; Nazarova, Iryna; Daschenko, Olga; Kapustiansky, Andry
2017-12-01
Energy efficiency improvement and ecological safety of heat power plants are urgent problems, which require scientifically grounded approaches and solutions. These problems can be solved partly within the presented heat-and-power cycles by including contact energy exchange equipment in the circuits of existing installations. A significant positive effect is obtained in the contact energy exchange installations, such as gas-steam installation `Aquarius' and the contact hydrogen heat generator that also can use hydrogen as a fuel. In these plants, the efficiency increases approximately by 10-12% in comparison with traditional installations, and the concentration of toxic substances, such as nitrogen oxides and carbon monoxide in flue gas can be reduced to 30 mg/m3 and to 5 mg/m3, respectively. Moreover, the plants additionally `generate' the clean water, which can be used for technical purposes.
Effectiveness of US state policies in reducing CO2 emissions from power plants
NASA Astrophysics Data System (ADS)
Grant, Don; Bergstrand, Kelly; Running, Katrina
2014-11-01
President Obama's landmark initiative to reduce the CO2 emissions of existing power plants, the nation's largest source of greenhouse gas (GHG) pollutants, depends heavily on states and their ability to devise policies that meet the goals set by the Environmental Protection Agency (EPA). Under the EPA's proposed Clean Power Plan, states will be responsible for cutting power plants' carbon pollution 30% from 2005 levels by 2030. States have already adopted several policies to reduce the electricity sector's climate impact. Some of these policies focus on reducing power plants' CO2 emissions, and others address this outcome in a more roundabout fashion by encouraging energy efficiency and renewable energy. However, it remains unclear which, if any, of these direct and indirect strategies actually mitigate plants' emissions because scholars have yet to test their effects using plant-level emission data. Here we use a newly released data source to determine whether states' policies significantly shape individual power plants' CO2 emissions. Findings reveal that certain types of direct strategy (emission caps and GHG targets) and indirect ones (public benefit funds and electric decoupling) lower plants' emissions and thus are viable building blocks of a federal climate regime.
Combined-cycle plant built in record time
DOE Office of Scientific and Technical Information (OSTI.GOV)
NONE
1995-04-01
This article reports that this low-cost cogeneration plant meets residential community`s environmental concerns with noise minimization, emissions control, and zero wastewater discharge. Supplying electricity to the local utility and steam to two hosts, the Auburndale cogeneration facility embodies the ``reference plant`` design approach developed by Westinghouse Power Generation (WPG), Orlando, Fla. With this approach customers meet their particular needs by choosing from a standard package of plant equipment and design options. Main goals of the concept are reduced construction time efficient and reliable power generation, minimal operating staff, and low cost. WPG built the plant on a turnkey basis formore » Auburndale Power Partners Limited Partnership (APP). APP is a partially owned subsidiary of Mission Energy, a California-based international developer and operator of independent-power facilities. The cogeneration facility supplies 150 MW of electric power to Florida Power Corp and exports 120,000 lb/hr of steam to Florida Distillers Co and Coca-Cola Foods.« less
Potentialities of TEC topping: A simplified view of parametric effects
NASA Technical Reports Server (NTRS)
Morris, J. F.
1980-01-01
An examination of the benefits of thermionic-energy-conversion (TEC)-topped power plants and methods of increasing conversion efficiency are discussed. Reductions in the cost of TEC modules yield direct decreases in the cost of electricity (COE) from TEC-topped central station power plants. Simplified COE, overall-efficiency charts presented illustrate this trend. Additional capital-cost diminution results from designing more compact furnaces with considerably increased heat transfer rates allowable and desirable for high temperature TEC and heat pipes. Such improvements can evolve of the protection from hot corrosion and slag as well as the thermal expansion compatibilities offered by silicon-carbide clads on TEC-heating surfaces. Greater efficiencies and far fewer modules are possible with high-temperature, high-power-density TEC: This decreases capital and fuel costs much more and substantially increases electric power outputs for fixed fuel inputs. In addition to more electricity, less pollution, and lower costs, TEC topping used directly in coal-combustion products contributes balance-of-payment gains.
Strategies for emission reduction from thermal power plants.
Prisyazhniuk, Vitaly A
2006-07-01
Major polluters of man's environment are thermal power stations (TPS) and power plants, which discharge into the atmosphere the basic product of carbon fuel combustion, CO2, which results in a build-up of the greenhouse effect and global warm-up of our planet's climate. This paper is intended to show that the way to attain environmental safety of the TPS and to abide by the decisions of the Kyoto Protocol lies in raising the efficiency of the heat power stations and reducing their fuel consumption by using nonconventional thermal cycles. Certain equations have been derived to define the quantitative interrelationship between the growth of efficiency of the TPS, decrease in fuel consumption and reduction of discharge of dust, fuel combustion gases, and heat into the environment. New ideas and new technological approaches that result in raising the efficiency of the TPS are briefly covered: magneto-hydrodynamic resonance, the Kalina cycle, and utilizing the ambient heat by using, as the working medium, low-boiling substances.
Cao, Fei; Li, Huashan; Zhang, Yang; Zhao, Liang
2013-01-01
The solar chimney power plant (SCPP) generates updraft wind through the green house effect. In this paper, the performances of two SCPP styles, that is, the conventional solar chimney power plant (CSCPP) and the sloped solar chimney power plant (SSCPP), are compared through a numerical simulation. A simplified Computational Fluid Dynamics (CFD) model is built to predict the performances of the SCPP. The model is validated through a comparison with the reported results from the Manzanares prototype. The annual performances of the CSCPP and the SSCPP are compared by taking Lanzhou as a case study. Numerical results indicate that the SSCPP holds a higher efficiency and generates smoother power than those of the CSCPP, and the effective pressure in the SSCPP is relevant to both the chimney and the collector heights.
Zhang, Yang; Zhao, Liang
2013-01-01
The solar chimney power plant (SCPP) generates updraft wind through the green house effect. In this paper, the performances of two SCPP styles, that is, the conventional solar chimney power plant (CSCPP) and the sloped solar chimney power plant (SSCPP), are compared through a numerical simulation. A simplified Computational Fluid Dynamics (CFD) model is built to predict the performances of the SCPP. The model is validated through a comparison with the reported results from the Manzanares prototype. The annual performances of the CSCPP and the SSCPP are compared by taking Lanzhou as a case study. Numerical results indicate that the SSCPP holds a higher efficiency and generates smoother power than those of the CSCPP, and the effective pressure in the SSCPP is relevant to both the chimney and the collector heights. PMID:24489515
DOE Office of Scientific and Technical Information (OSTI.GOV)
Heckmann, R.A.; Winget, R.N.; Infanger, R.C.
1984-01-31
Two series of experiments were completed to determine (a) toxicity of waste water from power plants on warm water fish and (b) multiple use of waste heat and water for aquatic animal and plant production. All three types of waste water from a typical coal-fired power plant are acceptable for growing catfish and tilapia following aeration. This growth was compared with fish raised in spring water. Closed, recirculating polyculture systems using evaporation pond water operated efficiently for plant (duckweed) and animal (fish and freshwater prawns) production. Duckweed is an excellent supplement for fish feed. Tilapia and freshwater prawns grew rapidlymore » in the tanks containing duckweed only. 10 references, 13 tables.« less
Validation of spatially resolved all sky imager derived DNI nowcasts
NASA Astrophysics Data System (ADS)
Kuhn, Pascal; Wilbert, Stefan; Schüler, David; Prahl, Christoph; Haase, Thomas; Ramirez, Lourdes; Zarzalejo, Luis; Meyer, Angela; Vuilleumier, Laurent; Blanc, Philippe; Dubrana, Jean; Kazantzidis, Andreas; Schroedter-Homscheidt, Marion; Hirsch, Tobias; Pitz-Paal, Robert
2017-06-01
Mainly due to clouds, Direct Normal Irradiance (DNI) displays short-term local variabilities affecting the efficiency of concentrating solar power (CSP) plants. To enable efficient plant operation, DNI nowcasts in high spatial and temporal resolutions for 15 to 30 minutes ahead are required. Ground-based All Sky Imagers (ASI) can be used to detect, track and predict 3D positions of clouds possibly shading the plant. The accuracy and reliability of these ASI-derived DNI nowcasts must be known to allow its application in solar power plants. Within the framework of the European project DNICast, an ASI-based nowcasting system was developed and implemented at the Plataforma Solar de Almería (PSA). Its validation methodology and validation results are presented in this work. The nowcasting system outperforms persistence forecasts for volatile irradiance situations.
NASA Astrophysics Data System (ADS)
Sasaki, Keiichi; Horikawa, Daisuke; Goto, Koichi
2015-01-01
Today, we face some significant environmental and energy problems such as global warming, urban heat island, and the precarious balance of world oil supply and demand. However, we have not yet found a satisfactory solution to these problems. Waste heat recovery is considered to be one of the best solutions because it can improve energy efficiency by converting heat exhausted from plants and machinery to electric power. This technology would also prevent atmospheric temperature increases caused by waste heat, and decrease fossil fuel consumption by recovering heat energy, thus also reducing CO2 emissions. The system proposed in this research generates electric power by providing waste heat or unharnessed thermal energy to built-in thermoelectric modules that can convert heat into electric power. Waste heat can be recovered from many places, including machinery in industrial plants, piping in electric power plants, waste incineration plants, and so on. Some natural heat sources such as hot springs and solar heat can also be used for this thermoelectric generation system. The generated power is expected to be supplied to auxiliary machinery around the heat source, stored as an emergency power supply, and so on. The attributes of this system are (1) direct power generation using hot springs or waste heat; (2) 24-h stable power generation; (3) stand-alone power system with no noise and no vibration; and (4) easy maintenance attributed to its simple structure with no moving parts. In order to maximize energy use efficiency, the temperature difference between both sides of the thermoelectric (TE) modules built into the system need to be kept as large as possible. This means it is important to reduce thermal resistance between TE modules and heat source. Moreover, the system's efficiency greatly depends on the base temperature of the heat sources and the material of the system's TE modules. Therefore, in order to make this system practical and efficient, it is necessary to choose the heat source first and then design the most appropriate structure for the source by applying analytical methods. This report describes how to design a prototype of a thermoelectric power generator using the analytical approach and the results of performance evaluation tests carried out in the field.
Surface Power Radiative Cooling Tests
NASA Astrophysics Data System (ADS)
Vaughn, Jason; Schneider, Todd
2006-01-01
Terrestrial nuclear power plants typically maintain their temperature through convective cooling, such as water and forced air. However, the space environment is a vacuum environment, typically 10-8 Torr pressure, therefore in proposed missions to the lunar surface, power plants would have to rely on radiative cooling to remove waste heat. Also, the Martian surface has a very tenuous atmosphere (e.g. ~5 Torr CO2), therefore, the main heat transfer method on the Martian surface is also radiative. Because of the lack of atmosphere on the Moon and the tenuous atmosphere on Mars, surface power systems on both the Lunar and Martian surface must rely heavily on radiative heat transfer. Because of the large temperature swings on both the lunar and the Martian surfaces, trying to radiate heat is inefficient. In order to increase power system efficiency, an effort is underway to test various combinations of materials with high emissivities to demonstrate their ability to survive these degrading atmospheres to maintain a constant radiator temperature improving surface power plant efficiency. An important part of this effort is the development of a unique capability that would allow the determination of a materials emissivity at high temperatures. A description of the test capability as well as initial data is presented.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Noble, Russell; Dombrowski, K.; Bernau, M.
Coal-based power generation systems provide reliable, low-cost power to the domestic energy sector. These systems consume large amounts of fuel and water to produce electricity and are the target of pending regulations that may require reductions in water use and improvements in thermal efficiency. While efficiency of coal-based generation has improved over time, coal power plants often do not utilize the low-grade heat contained in the flue gas and require large volumes of water for the steam cycle make-up, environmental controls, and for process cooling and heating. Low-grade heat recovery is particularly challenging for coal-fired applications, due in large partmore » to the condensation of acid as the flue gas cools and the resulting potential corrosion of the heat recovery materials. Such systems have also not been of significant interest as recent investments on coal power plants have primarily been for environmental controls due to more stringent regulations. Also, in many regions, fuel cost is still a pass-through to the consumer, reducing the motivation for efficiency improvements. Therefore, a commercial system combining low-grade heat-recovery technologies and associated end uses to cost effectively improve efficiency and/or reduce water consumption has not yet been widely applied. However, pressures from potential new regulations and from water shortages may drive new interest, particularly in the U.S. In an effort to address this issue, the U.S. Department of Energy (DOE) has sought to identify and promote technologies to achieve this goal.« less
Weather Driven Renewable Energy Analysis, Modeling New Technologies
NASA Astrophysics Data System (ADS)
Paine, J.; Clack, C.; Picciano, P.; Terry, L.
2015-12-01
Carbon emission reduction is essential to hampering anthropogenic climate change. While there are several methods to broach carbon reductions, the National Energy with Weather System (NEWS) model focuses on limiting electrical generation emissions by way of a national high-voltage direct-current transmission that takes advantage of the strengths of different regions in terms of variable sources of energy. Specifically, we focus upon modeling concentrating solar power (CSP) as another source to contribute to the electric grid. Power tower solar fields are optimized taking into account high spatial and temporal resolution, 13km and hourly, numerical weather prediction model data gathered by NOAA from the years of 2006-2008. Importantly, the optimization of these CSP power plants takes into consideration factors that decrease the optical efficiency of the heliostats reflecting solar irradiance. For example, cosine efficiency, atmospheric attenuation, and shadowing are shown here; however, it should be noted that they are not the only limiting factors. While solar photovoltaic plants can be combined for similar efficiency to the power tower and currently at a lower cost, they do not have a cost-effective capability to provide electricity when there are interruptions in solar irradiance. Power towers rely on a heat transfer fluid, which can be used for thermal storage changing the cost efficiency of this energy source. Thermal storage increases the electric stability that many other renewable energy sources lack, and thus, the ability to choose between direct electric conversion and thermal storage is discussed. The figure shown is a test model of a CSP plant made up of heliostats. The colors show the optical efficiency of each heliostat at a single time of the day.
Methods of reducing energy consumption of the oxidant supply system for MHD/steam power plants
NASA Technical Reports Server (NTRS)
Juhasz, A. J.
1983-01-01
An in-depth study was conducted to identify possible improvements to the oxidant supply system for combined cycle MHD power plants which would lead to higher thermal efficiency and reduction in the cost of electricity, COE. Results showed that the oxidant system energy consumption could be minimized when the process was designed to deliver a product O2 concentration of 70 mole percent. The study also led to the development of a new air separation process, referred to as liquid pumping and internal compression. MHD system performance calculations show that the new process would permit an increase in plant thermal efficiency of 0.6 percent while allowing more favorable tradeoffs between magnetic energy and oxidant system capacity requirements.
Methods of reducing energy consumption of the oxidant supply system for MHD/steam power plants
NASA Technical Reports Server (NTRS)
Juhasz, A. J.
1983-01-01
An in-depth study was conducted to identify possible improvements to the oxidant supply system for combined cycle MHD power plants which would lead to higher thermal efficiency and reduction in the cost of electricity, COE. Results showed that the oxidant system energy consumption could be minimized when the process was designed to deliver a product O2 concentration of 70 mole percent. The study also led to the development of a new air separation process, referred to as 'liquid pumping and internal compression'. MHD system performance calculations show that the new process would permit an increase in plant thermal efficiency of 0.6 percent while allowing more favorable tradeoffs between magnetic energy and oxidant system capacity requirements.
Thermodynamic Study of Multi Pressure HRSG in Gas/Steam Combined Cycle Power Plant
NASA Astrophysics Data System (ADS)
Sharma, Meeta; Singh, Onkar
2018-01-01
Combined cycle power plants have a combination of gas based topping cycle and steam based bottoming cycle through the use of Heat Recovery Steam Generator (HRSG). These HRSG may be either of single pressure (SP) or dual pressure (DP) or multiple pressure type. Here in this study thermodynamic analysis is carried out for optimal performance of HRSG using different types of HRSG layout for combined cycle efficiency improvement. Performance of single pressure HRSG and dual pressure HRSG, utilized in gas/steam combined cycle is analyzed and presented here. In comparison to single pressure, dual pressure HRSG offers 10 to 15% higher reduction in stack temperature due to greater heat recovery and thus improved plant efficiency.
Development of Flexi-Burn™ CFB Power Plant to Meet the Challenge of Climate Change
NASA Astrophysics Data System (ADS)
Hackt, Horst; Fant, Zhen; Seltzert, Andrew; Hotta, Arto; Erikssoni, Timo; Sippu, Ossi
Carbon-dioxide capture and storage (CCS) offers the potential for major reductions in carbon- dioxide emissions of fossil fuel-based power generation in the fairly short term, and oxyfuel combustion is one of the identified CCS technology options. Foster Wheeler (FW) is working on reduction of carbon-dioxide with its integrated Flexi-Burn™ CFB technology. The proven high efficiency circulating fluidized-bed (CFB) technology, when coupled with air separation units and carbon purification units, offers a solution for carbon dioxide reduction both in re-powering and in greenfield power plants. CFB technology has the advantages over pulverized coal technology of a more uniform furnace heat flux, increased fuel flexibility and offers the opportunity to further reduce carbon dioxide emissions by co-firing coal with bio-fuels. Development and design of an integrated Flexi-Bum™ CFB steam generator and balance of plant system was conducted for both air mode and oxyfuel mode. Through proper configuration and design, the same steam generator can be switched from air mode to oxyfuel mode without the need for unit shutdown for modifications. The Flexi-Burn™ CFB system incorporates features to maximize plant efficiency and power output when operating in the oxy-firing mode through firing more fuel in the same boiler.
NASA Technical Reports Server (NTRS)
Wang, S. Y.; Smith, J. M.
1982-01-01
It is noted that operating conditions which yielded a peak thermodynamic efficiency (41%) for an EFT-size MHD/steam power plant were previously (Wang et al., 1981; Staiger, 1981) identified by considering only the active region (the primary portion for power production) of an MHD channel. These previous efforts are extended here to include an investigation of the effects of the channel end regions on overall power generation. Considering these effects, the peak plant thermodynamic efficiency is found to be slightly lowered (40.7%); the channel operating point for peak efficiency is shifted to the supersonic mode (Mach number of approximately 1.1) rather than the previous subsonic operation (Mach number of approximately 0.9). Also discussed is the sensitivity of the channel performance to the B-field, diffuser recovery coefficient, channel load parameter, Mach number, and combustor pressure.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Albrecht H. Mayer
Asea Brown Boveri (ABB) has completed its technology based program. The results developed under Work Breakdown Structure (WBS) 8, concentrated on technology development and demonstration have been partially implemented in newer turbine designs. A significant improvement in heat rate and power output has been demonstrated. ABB will use the knowledge gained to further improve the efficiency of its Advanced Cycle System, which has been developed and introduced into the marked out side ABB's Advanced Turbine System (ATS) activities. The technology will lead to a power plant design that meets the ATS performance goals of over 60% plant efficiency, decreased electricitymore » costs to consumers and lowest emissions.« less
NASA Astrophysics Data System (ADS)
Sedlov, A.; Dorokhov, Y.; Rybakov, B.; Nenashev, A.
2017-11-01
At the stage of pre-proposals unit of the thermal power plants for regions with a hot climate requires a design study on the efficiency of possible options for the structure of the thermal circuit and a set of key parameters. In this paper, the thermal circuit of the condensing unit powerfully 350 MW. The main feature of the external conditions of thermal power plants in hot climates is the elevated temperature of cooling water of the turbine condensers. For example, in the Persian Gulf region as the cooling water is sea water. In the hot season of the year weighted average sea water temperature of 30.9 °C and during the cold season to 22.8 °C. From the turbine part of the steam is supplied to the distillation-desalination plant. In the hot season of the year heat scheme with pressure fresh pair of 23.54 MPa, temperature 570/560 °C and feed pump with electric drive (EDP) is characterized by a efficiency net of 0.25% higher than thermal schem with feed turbine pump (TDP). However, the supplied power unit with PED is less by 11.6 MW. Calculations of thermal schemes in all seasons of the year allowed us to determine the difference in the profit margin of units of the TDP and EDP. During the year the unit with the TDP provides the ability to obtain the profit margin by 1.55 million dollars more than the unit EDP. When using on the market subsidized price of electricity (Iran) marginal profit of a unit with TDP more at 7.25 million dollars.
An enhancement of NASTRAN for the seismic analysis of structures. [nuclear power plants
NASA Technical Reports Server (NTRS)
Burroughs, J. W.
1980-01-01
New modules, bulk data cards and DMAP sequence were added to NASTRAN to aid in the seismic analysis of nuclear power plant structures. These allow input consisting of acceleration time histories and result in the generation of acceleration floor response spectra. The resulting system contains numerous user convenience features, as well as being reasonably efficient.
Conceptual study of a 250 kW planar SOFC system for CHP application
NASA Astrophysics Data System (ADS)
Fontell, E.; Kivisaari, T.; Christiansen, N.; Hansen, J.-B.; Pålsson, J.
In August 2002, Wärtsilä Corporation and Haldor Topsøe A/S entered into a co-operation agreement to start joint development program within the planar SOFC technology. The development program aims to bring to the market highly efficient, clean and cost competitive fuel cell systems with power outputs above 200 kW for distributed power generation with CHP and for marine applications. In this study, the product concept for a 250 kW natural gas-fuelled atmospheric SOFC plant has been studied. The process has been calculated and optimised for high electrical efficiency. In the calculations, system efficiencies more than 55-85% (electrical co-generation) have been reached. The necessary balance of plant (BoP) components have been identified and the concept for grid connection has been defined. The BoP includes fuel and air supply, anode re-circulation, start-up steam, purge gas, exhaust gas heat recovery, back-up power, power electronics and control system. Based on the analysed system and component information, a conceptual design and cost break down structure for the product have been made. The cost breakdown shows that the stack, system control and power electronics are the major cost factors, while the remaining BoP equipment stands for a minor share of the manufacturing cost. Finally, the feasibility of the SOFC plants has been compared to gas engines.
Water use at pulverized coal power plants with postcombustion carbon capture and storage.
Zhai, Haibo; Rubin, Edward S; Versteeg, Peter L
2011-03-15
Coal-fired power plants account for nearly 50% of U.S. electricity supply and about a third of U.S. emissions of CO(2), the major greenhouse gas (GHG) associated with global climate change. Thermal power plants also account for 39% of all freshwater withdrawals in the U.S. To reduce GHG emissions from coal-fired plants, postcombustion carbon capture and storage (CCS) systems are receiving considerable attention. Current commercial amine-based capture systems require water for cooling and other operations that add to power plant water requirements. This paper characterizes and quantifies water use at coal-burning power plants with and without CCS and investigates key parameters that influence water consumption. Analytical models are presented to quantify water use for major unit operations. Case study results show that, for power plants with conventional wet cooling towers, approximately 80% of total plant water withdrawals and 86% of plant water consumption is for cooling. The addition of an amine-based CCS system would approximately double the consumptive water use of the plant. Replacing wet towers with air-cooled condensers for dry cooling would reduce plant water use by about 80% (without CCS) to about 40% (with CCS). However, the cooling system capital cost would approximately triple, although costs are highly dependent on site-specific characteristics. The potential for water use reductions with CCS is explored via sensitivity analyses of plant efficiency and other key design parameters that affect water resource management for the electric power industry.
Operational status and current trends in gas turbines for utility applications in Europe
DOE Office of Scientific and Technical Information (OSTI.GOV)
Harmon, R.A.
1976-08-16
This investigation was conducted to ascertain the operational status and current trends in gas turbines for electric utility applications in Europe. A number of selected organizations were contacted by letter and personal visits and readily available pertinent literature was reviewed. The impact of business recovery in 1976 and increases in power demand on gas turbine operation and design trends is reflected in the following: annual operating hours on simple cycle gas turbines is very low in favor of more efficient combined cycle or steam plants which comprise part of the present excess reserve capacity; economics indicates the need for highermore » single unit ratings, e.g., in the 100 MW power range; inquiries and discussion of new plants are predominantly for more efficient systems--combined cycles and/or exhaust heat utilization; dual-purpose heat and power plants are getting much more attention; re-powering of existing steam plants is an attractive approach which has been demonstrated and should expand in use; ability to burn (or handle) dirty fuels is important; closed cycle gas turbine plants are receiving renewed consideration because of their good operational experience with dirty fuels including coal, flexibility in supplying varying amounts of heat and power with independent control, low pollution characteristics, ability to use over 80 percent of the heat content in thefuel, and potential for advantageous use in direct cycle, gas cooled nuclear power stations; the broad use of nuclear energy appears inevitable, and the potential advantages of direct cycle gas cooled systems with helium turbines offer incentives of increased efficiency, safety, and lower cost; and component trends are toward higher turbine inlet temperatures (1700 to 2000/sup 0/F) and toward higher compressor pressure ratios and variable geometry. Gas turbines are expected to play an important and continuing role in the utility industry in accordance with its changing requirements.« less
NASA Astrophysics Data System (ADS)
Kartashev, A. L.; Vaulin, S. D.; Kartasheva, M. A.; Martynov, A. A.; Safonov, E. V.
2016-06-01
This article presents information about the main distinguishing features of microturbine power plants. The justification of the use of Francis turbine in microturbine power plants with rated power of 100 kW is given. Initial analytical engineering calculations of the turbine (without using computational fluid dynamics) with appropriate calculation methods are considered. The parametric study of nozzle blade and whole turbine stage using ANSYS CFX is descripted. The calculations determined the optimal geometry on the criterion of maximizing efficiency at total pressure ratio. The calculation results are presented in graphical form, as well as the velocity and pressure fields at the interscapular channels of nozzle unit and the impeller.
Water treatment plants assessment at Talkha power plant.
El-Sebaie, Olfat D; Abd El-Kerim, Ghazy E; Ramadan, Mohamed H; Abd El-Atey, Magda M; Taha, Sahr Ahmed
2002-01-01
Talkha power plant is the only power plant located in El-Mansoura. It generates electricity using two different methods by steam turbine and gas turbine. Both plants drew water from River Nile (208 m3 /h). The Nile raw water passes through different treatment processes to be suitable for drinking and operational uses. At Talkha power plant, there are two purification plants used for drinking water supply (100 m3/h) and for water demineralization supply (108 m3/h). This study aimed at studying the efficiency of the water purification plants. For drinking water purification plant, the annual River Nile water characterized by slightly alkaline pH (7.4-8), high annual mean values of turbidity (10.06 NTU), Standard Plate Count (SPC) (313.3 CFU/1 ml), total coliform (2717/100 ml), fecal coliform (0-2400/100 ml), and total algae (3 x 10(4) org/I). The dominant group of algae all over the study period was green algae. The blue green algae was abundant in Summer and Autumn seasons. The pH range, and the annual mean values of turbidity, TDS, total hardness, sulfates, chlorides, nitrates, nitrites, fluoride, and residual chlorine for purified water were in compliance with Egyptian drinking water standards. All the SPC recorded values with an annual mean value of 10.13 CFU/1 ml indicated that chlorine dose and contact time were not enough to kill the bacteria. However, they were in compliance with Egyptian decree (should not exceed 50 CFU/1 ml). Although the removal efficiency of the plant for total coliform and blue green algae was high (98.5% and 99.2%, respectively), the limits of the obtained results with an annual mean values of 40/100 ml and 15.6 org/l were not in compliance with the Egyptian decree (should be free from total coliform, fecal coliform and blue green algae). For water demineralization treatment plant, the raw water was characterized by slightly alkaline pH. The annual mean values of conductivity, turbidity, and TDS were 354.6 microS/cm, 10.84 NTU, and 214.6 mg/I, respectively. There was an increase in the results of conductivity, turbidity, total hardness, and TDS in carbon filter effluent which was attributed to the desorption of adsorbed ions on the carbon media. The removal efficiencies of turbidity, total hardness, and TDS indicated the high efficiency of the cationic filter. The annual removal efficiencies of conductivity, turbidity, chloride, and TDS proved the efficiency of the anionic filter for removing the dissolved and suspended ions. All of the recorded values of the pH, conductivity, turbidity, chlorides, hardness, and TDS of the mixed bed effluent indicated that the water at this stage was of high quality for boiler feed. The study recommended adjustment of coagulant and residual chlorine doses as well as contact time, and continuous monitoring and maintenance of the different units.
Mercury emission and speciation of coal-fired power plants in China
NASA Astrophysics Data System (ADS)
Wang, S. X.; Zhang, L.; Li, G. H.; Wu, Y.; Hao, J. M.; Pirrone, N.; Sprovieri, F.; Ancora, M. P.
2010-02-01
Comprehensive field measurements are needed to understand the mercury emissions from Chinese power plants and to improve the accuracy of emission inventories. Characterization of mercury emissions and their behavior were measured in six typical coal-fired power plants in China. During the tests, the flue gas was sampled simultaneously at inlet and outlet of Selective Catalytic Reduction (SCR), electrostatic precipitators (ESP), and flue gas desulfurization (FGD) using the Ontario Hydro Method (OHM). The pulverized coal, bottom ash, fly ash and gypsum were also sampled in the field. Mercury concentrations in coal burned in the measured power plants ranged from 17 to 385 μg/kg. The mercury mass balances for the six power plants varied from 87 to 116% of the input coal mercury for the whole system. The total mercury concentrations in the flue gas from boilers were at the range of 1.92-27.15 μg/m3, which were significantly related to the mercury contents in burned coal. The mercury speciation in flue gas right after the boiler is influenced by the contents of halogen, mercury, and ash in the burned coal. The average mercury removal efficiencies of ESP, ESP plus wet FGD, and ESP plus dry FGD-FF systems were 24%, 73% and 66%, respectively, which were similar to the average removal efficiencies of pollution control device systems in other countries such as US, Japan and South Korea. The SCR system oxidized 16% elemental mercury and reduced about 32% of total mercury. Elemental mercury, accounting for 66-94% of total mercury, was the dominant species emitted to the atmosphere. The mercury emission factor was also calculated for each power plant.
Mercury emission and speciation of coal-fired power plants in China
NASA Astrophysics Data System (ADS)
Wang, S.; Zhang, L.; Li, G.; Wu, Y.; Hao, J.; Pirrone, N.; Sprovieri, F.; Ancora, M. P.
2009-11-01
Comprehensive field measurements are needed to understand the mercury emissions from Chinese power plants and to improve the accuracy of emission inventories. Characterization of mercury emissions and their behavior were measured in six typical coal-fired power plants in China. During the tests, the flue gas was sampled simultaneously at inlet and outlet of selective catalyst reduction (SCR), electrostatic precipitators (ESP), and flue gas desulfurization (FGD) using the Ontario Hydro Method (OHM). The pulverized coal, bottom ash, fly ash and gypsum were also sampled in the field. Mercury concentrations in coal burned in the measured power plants ranged from 17 to 385 μg/kg. The mercury mass balances for the six power plants varied from 87 to 116% of the input coal mercury for the whole system. The total mercury concentrations in the flue gas from boilers were at the range of 1.92-27.15 μg/m3, which were significantly related to the mercury contents in burned coal. The mercury speciation in flue gas right after the boiler is influenced by the contents of halogen, mercury, and ash in the burned coal. The average mercury removal efficiencies of ESP, ESP plus wet FGD, and ESP plus dry FGD-FF systems were 24%, 73% and 66%, respectively, which were similar to the average removal efficiencies of pollution control device systems in other countries such as US, Japan and South Korea. The SCR system oxidized 16% elemental mercury and reduced about 32% of total mercury. Elemental mercury, accounting for 66-94% of total mercury, was the dominant species emitted to the atmosphere. The mercury emission factor was also calculated for each power plant.
Regulation of suspended particulate matter (SPM) in Indian coal-based thermal power plants
NASA Astrophysics Data System (ADS)
Sengupta, Ishita
Air borne particulate matter, in major Indian cities is at least three times the standard prescribed by the WHO. Coal-based thermal power plants are the major emitters of particulate matter in India. The lack of severe penalty for non-compliance with the standards has worsened the situation and thus calls for an immediate need for investment in technologies to regulate particulate emissions. My dissertation studies the optimal investment decisions in a dynamic framework, for a random sample of forty Indian coal-based power plants to abate particulate emissions. I used Linear Programming to solve the double cost minimization problem for the optimal choices of coal, boiler and pollution-control equipment. A policy analysis is done to choose over various tax policies, which would induce the firms to adopt the energy efficient as well as cost efficient technology. The aim here is to reach the WHO standards. Using the optimal switching point model I show that in a dynamic set up, switching the boiler immediately is always the cost effective option for all the power plants even if there is no policy restriction. The switch to a baghouse depends upon the policy in place. Theoretically, even though an emission tax is considered the most efficient tax, an ash tax or a coal tax can also be considered to be a good substitute especially in countries like India where monitoring costs are very high. As SPM is a local pollutant the analysis here is mainly firm specific.
Life Cycle Assessment of Coal-fired Power Production
DOE Office of Scientific and Technical Information (OSTI.GOV)
Spath, P. L.; Mann, M. K.; Kerr, D. R.
1999-09-01
Coal has the largest share of utility power generation in the US, accounting for approximately 56% of all utility-produced electricity (US DOE, 1998). Therefore, understanding the environmental implications of producing electricity from coal is an important component of any plan to reduce total emissions and resource consumption. A life cycle assessment (LCA) on the production of electricity from coal was performed in order to examine the environmental aspects of current and future pulverized coal boiler systems. Three systems were examined: (1) a plant that represents the average emissions and efficiency of currently operating coal-fired power plants in the US (thismore » tells us about the status quo), (2) a new coal-fired power plant that meets the New Source Performance Standards (NSPS), and (3) a highly advanced coal-fired power plant utilizing a low emission boiler system (LEBS).« less
NASA Astrophysics Data System (ADS)
Dyachenko, F. V.; Petrova, T. I.
2017-11-01
Efficiency and reliability of the equipment in fossil power plants as well as in combined cycle power plants depend on the corrosion processes and deposit formation in steam/water circuit. In order to decrease these processes different water chemistries are used. Today the great attention is being attracted to the application of film forming amines and film forming amine products. The International Association for the Properties of Water and Steam (IAPWS) consolidated the information from all over the World, and based on the research studies and operating experience of researchers and engineers from 21 countries, developed and authorized the Technical Guidance Document: “Application of Film Forming Amines in Fossil, Combined Cycle, and Biomass Power Plants” in 2016. This article describe Russian and International technical guidance documents for the cycle water chemistries based on film forming amines at fossil and combined cycle power plants.
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.
Loss of Load Probability Calculation for West Java Power System with Nuclear Power Plant Scenario
NASA Astrophysics Data System (ADS)
Azizah, I. D.; Abdullah, A. G.; Purnama, W.; Nandiyanto, A. B. D.; Shafii, M. A.
2017-03-01
Loss of Load Probability (LOLP) index showing the quality and performance of an electrical system. LOLP value is affected by load growth, the load duration curve, forced outage rate of the plant, number and capacity of generating units. This reliability index calculation begins with load forecasting to 2018 using multiple regression method. Scenario 1 with compositions of conventional plants produce the largest LOLP in 2017 amounted to 71.609 days / year. While the best reliability index generated in scenario 2 with the NPP amounted to 6.941 days / year in 2015. Improved reliability of systems using nuclear power more efficiently when compared to conventional plants because it also has advantages such as emission-free, inexpensive fuel costs, as well as high level of plant availability.
NASA Astrophysics Data System (ADS)
Wolf, D.
A fully functionally efficient solar-thermal power plant (10 kW electric) was built. The operating principle of thermomechanical conversion of solar energy into mechanical or electrical energy is presented. The equipment is completely automatic. Flat plate collectors absorb solar energy and convert it into heat which is transmitted by water to a heat exchanger. A closed cycle machine uses the heat to boil a working fluid (C2C12F4). A screw, powered by gas expansion in the working fluid, converts mechanical energy into electrical energy.
Polish plant beats the odds to become model EU generator
DOE Office of Scientific and Technical Information (OSTI.GOV)
Neville, A.
2009-03-15
Once a Soviet satellite, Poland is now transforming into a thoroughly modern nation. To support its growing economy, this recent European Union member country is modernizing its power industry. Exemplifying the advances in the Polish electricity generation market is the 460 MW Patnow II power plant - the largest, most efficient (supercritical cycle) and environmentally cleanest lignite-fired unit in the country. 3 photos.
Flexibility of CCS Power Plants and Transport Systems
NASA Astrophysics Data System (ADS)
Nimtz, Michael; Krautz, Hans-Joachim
2013-04-01
Growing shares of renewable energy in the German power grid urge fossil fuelled power plants to reduce load or to shut down completely with increasing frequency and amplitude. Shut down, load changes and the following restart or ramp-up often have to be carried out as fast as possible. To realize such fast transitions is already complicated and expensive for conventional power plants - if further measures for CO2 reduction are applied, the task is even harder. Capture equipment and transport systems will add further process steps as well as additional masses of fluids and construction material. This will result in a change of time constants and a generally slower system reaction on changes in parameters like load, temperature and pressure in the power plant components and capture units. On the other hand there is only limited time to earn money by selling electricity - if there is a chance to sell more electricity in a short term, efficiencies should be as high as possible. Any capture unit that would reduce the efficiency causes economic conflicts. Therefore measures are analysed to offset the power generation from the capture process in time or to reduce the capture load temporarily. The poster will present a case study for different CCS power plant configurations and load scenarios representing typical grid load from renewable energies. Approaches to balance the load and/or the CO2 output of these power plants will be presented. These approaches comprise: bypassing of flue gas, intermediate storage of heat and/or fluids. Amounts of additional steam, electrical energy and other process fluids (e.g. scrubbing fluids like MEA) and size of auxiliary equipment will be shown .Finally, effects on the transport system (e.g. cooling down of CO2 in the pipeline and changes in mass and volume flow) will be presented and discussed.
NASA Astrophysics Data System (ADS)
Lei, Qi; Bader, Roman; Kreider, Peter; Lovegrove, Keith; Lipiński, Wojciech
2017-11-01
We explore the thermodynamic efficiency of a solar-driven combined cycle power system with manganese oxide-based thermochemical energy storage system. Manganese oxide particles are reduced during the day in an oxygen-lean atmosphere obtained with a fluidized-bed reactor at temperatures in the range of 750-1600°C using concentrated solar energy. Reduced hot particles are stored and re-oxidized during night-time to achieve continuous power plant operation. The steady-state mass and energy conservation equations are solved for all system components to calculate the thermodynamic properties and mass flow rates at all state points in the system, taking into account component irreversibilities. The net power block and overall solar-to-electric energy conversion efficiencies, and the required storage volumes for solids and gases in the storage system are predicted. Preliminary results for a system with 100 MW nominal solar power input at a solar concentration ratio of 3000, designed for constant round-the-clock operation with 8 hours of on-sun and 16 hours of off-sun operation and with manganese oxide particles cycled between 750 and 1600°C yield a net power block efficiency of 60.0% and an overall energy conversion efficiency of 41.3%. Required storage tank sizes for the solids are estimated to be approx. 5-6 times smaller than those of state-of-the-art molten salt systems.
NASA Astrophysics Data System (ADS)
Miara, A.; Vorosmarty, C. J.; Stewart, R. J.; Wollheim, W. M.; Rosenzweig, B.
2012-12-01
In the Northeast US, approximately 80% of the available capacity of thermoelectric plants is dependent on the constant availability of water for cooling. Cooling is a necessary process whereby the waste thermal load of a power plant is released and the working fluid (typically steam) condensed to allow the continuation of the thermodynamic cycle and the extraction of electrical power through the action of turbines. Power plants rely on a minimum flow at a certain temperature, determined by the individual plant engineering design, to be sufficiently low for their cooling. Any change in quantity or temperature of water could reduce thermal efficiencies. As a result of the cooling process, power plants emit thermal pollution into receiving waters, which is harmful to freshwater aquatic ecosystems including its resident life forms and their biodiversity. The Clean Water Act of 1972 (CWA) was established to limit thermal pollution, particularly when rivers reach high temperatures. When river temperatures approach the threshold limit, the power plants that use freshwater for cooling are forced to reduce their thermal load and thus their output to comply with the regulations. Here we describe a model that quantifies, in a regional context, thermal pollution and estimates efficiency losses as a result of fluctuating river temperatures and flow. It does this using available data, standard engineering equations describing the heat cycle of power plants and their water use, and assumptions about the operations of the plant. In this presentation, we demonstrate the model by analyzing contrasting climates with and without the CWA, focusing on the productivity of 366 thermoelectric plants that rely on water for cooling in the Northeast between the years 2000-2010. When the CWA was imposed on all simulated power plants, the model shows that during the average winter and summer, 94% and 71% of required generation was met from the power plants, respectively. This suggests that if all power plants were to comply with the CWA and if temperatures do increase in the future as is expected under greenhouse warming, electric power generation in the Northeast may become limited, particularly in the summer. To avoid a potential energy gap, back-up generators and other electric infrastructure, such as hydropower, may have to come online in order to meet the total electric demand. Furthermore, it is clear that the methodology and steps taken in the model are required to more accurately understand, estimate and evaluate the relationship between energy production, environmental and energy policy and biodiversity under forecasted and historic climate conditions. Our ongoing work uses this model to explore various future scenarios of policy, climate and natural resource management in the Northeastern US for the period 2010-2100.
NASA Astrophysics Data System (ADS)
Hart, E. K.; Jacobson, M. Z.; Dvorak, M. J.
2008-12-01
Time series power flow analyses of the California electricity grid are performed with extensive addition of intermittent renewable power. The study focuses on the effects of replacing non-renewable and imported (out-of-state) electricity with wind and solar power on the reliability of the transmission grid. Simulations are performed for specific days chosen throughout the year to capture seasonal fluctuations in load, wind, and insolation. Wind farm expansions and new wind farms are proposed based on regional wind resources and time-dependent wind power output is calculated using a meteorological model and the power curves of specific wind turbines. Solar power is incorporated both as centralized and distributed generation. Concentrating solar thermal plants are modeled using local insolation data and the efficiencies of pre-existing plants. Distributed generation from rooftop PV systems is included using regional insolation data, efficiencies of common PV systems, and census data. The additional power output of these technologies offsets power from large natural gas plants and is balanced for the purposes of load matching largely with hydroelectric power and by curtailment when necessary. A quantitative analysis of the effects of this significant shift in the electricity portfolio of the state of California on power availability and transmission line congestion, using a transmission load-flow model, is presented. A sensitivity analysis is also performed to determine the effects of forecasting errors in wind and insolation on load-matching and transmission line congestion.
Parametric analysis of closed cycle magnetohydrodynamic (MHD) power plants
NASA Technical Reports Server (NTRS)
Owens, W.; Berg, R.; Murthy, R.; Patten, J.
1981-01-01
A parametric analysis of closed cycle MHD power plants was performed which studied the technical feasibility, associated capital cost, and cost of electricity for the direct combustion of coal or coal derived fuel. Three reference plants, differing primarily in the method of coal conversion utilized, were defined. Reference Plant 1 used direct coal fired combustion while Reference Plants 2 and 3 employed on site integrated gasifiers. Reference Plant 2 used a pressurized gasifier while Reference Plant 3 used a ""state of the art' atmospheric gasifier. Thirty plant configurations were considered by using parametric variations from the Reference Plants. Parametric variations include the type of coal (Montana Rosebud or Illinois No. 6), clean up systems (hot or cold gas clean up), on or two stage atmospheric or pressurized direct fired coal combustors, and six different gasifier systems. Plant sizes ranged from 100 to 1000 MWe. Overall plant performance was calculated using two methodologies. In one task, the channel performance was assumed and the MHD topping cycle efficiencies were based on the assumed values. A second task involved rigorous calculations of channel performance (enthalpy extraction, isentropic efficiency and generator output) that verified the original (task one) assumptions. Closed cycle MHD capital costs were estimated for the task one plants; task two cost estimates were made for the channel and magnet only.
NASA Astrophysics Data System (ADS)
Nakai, S.; Yamanaka, M.; Kitagawa, Y.; Fujita, K.; Heya, M.; Mima, K.; Izawa, Y.; Nakatsuka, M.; Murakami, M.; Ueda, K.; Sasaki, T.; Mori, Y.; Kanabe, T.; Hiruma, T.; Kan, H.; Kawashima, T.
2006-06-01
The typical specifications of the laser driver for a commercial IFE power plant are (1) total energy (MJ/pulse) with a tailored 20-40 ns pulse, (2) repetition operation (˜ 10 Hz), (3) efficiency (˜ 10%) with enough robustness and low cost. The key elements of the DPSSL driver technology are under development with HALNA. The HALNA 10 (High Average-power Laser for Nuclear-fusion Application) demonstrated 10 J × 10 Hz operation and the HALNA 100 (100 J × 10 Hz) is now under construction. By using the high average power and high intensity lasers, new industrial applications are being proceeded. The collaborative process for the development of high power laser with industry and for the industrial applications is effective and essential in the development of the laser driver for IFE power plant.
Heat Transfer Phenomena in Concentrating Solar Power Systems.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Armijo, Kenneth Miguel; Shinde, Subhash L.
Concentrating solar power (CSP) utilizes solar thermal energy to drive a thermal power cycle for the generation of electricity. CSP systems are facilitated as large, centralized power plants , such as power towers and trough systems, to take advantage of ec onomies of scale through dispatchable thermal energy storage, which is a principle advantage over other energy generation systems . Additionally, the combination of large solar concentration ratios with high solar conversion efficiencies provides a strong o pportunity of employment of specific power cycles such as the Brayton gas cycle that utilizes super critical fluids such as supercritical carbon dioxidemore » (s CO 2 ) , compared to other sola r - fossil hybrid power plants. A comprehensive thermal - fluids examination is provided by this work of various heat transfer phenomena evident in CSP technologies. These include sub - systems and heat transfer fundamental phenomena evident within CSP systems , which include s receivers, heat transfer fluids (HTFs), thermal storage me dia and system designs , thermodynamic power block systems/components, as well as high - temperature materials. This work provides literature reviews, trade studies, and phenomenological comparisons of heat transfer media (HTM) and components and systems, all for promotion of high performance and efficient CSP systems. In addition, f urther investigations are also conducted that provide advanced heat transfer modeling approaches for gas - particle receiver systems , as well as performance/efficiency enhancement re commendations, particularly for solarized supercritical power systems .« less
Simultaneous Waste Heat and Water Recovery from Power Plant Flue Gases for Advanced Energy Systems
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wang, Dexin
This final report presents the results of a two-year technology development project carried out by a team of participants sponsored by the Department of Energy (DOE). The objective of this project is to develop a membrane-based technology to recover both water and low grade heat from power plant flue gases. Part of the recovered high-purity water and energy can be used directly to replace plant boiler makeup water as well as improving its efficiency, and the remaining part of the recovered water can be used for Flue Gas Desulfurization (FGD), cooling tower water makeup or other plant uses. This advancedmore » version Transport Membrane Condenser (TMC) with lower capital and operating costs can be applied to existing plants economically and can maximize waste heat and water recovery from future Advanced Energy System flue gases with CO 2 capture in consideration, which will have higher moisture content that favors the TMC to achieve higher efficiency.« less
Optimization of power-cycle arrangements for Supercritical Water cooled Reactors (SCWRs)
NASA Astrophysics Data System (ADS)
Lizon-A-Lugrin, Laure
The world energy demand is continuously rising due to the increase of both the world population and the standard of life quality. Further, to assure both a healthy world economy as well as adequate social standards, in a relatively short term, new energy-conversion technologies are mandatory. Within this framework, a Generation IV International Forum (GIF) was established by the participation of 10 countries to collaborate for developing nuclear power reactors that will replace the present technology by 2030. The main goals of these nuclear-power reactors are: economic competitiveness, sustainability, safety, reliability and resistance to proliferation. As a member of the GIF, Canada has decided to orient its efforts towards the design of a CANDU-type Super Critical Water-cooled Reactor (SCWR). Such a system must run at a coolant outlet temperature of about 625°C and at a pressure of 25 MPa. It is obvious that at such conditions the overall efficiency of this kind of Nuclear Power Plant (NPP) will compete with actual supercritical water-power boilers. In addition, from a heat-transfer viewpoint, the use of a supercritical fluid allows the limitation imposed by Critical Heat Flux (CHF) conditions, which characterize actual technologies, to be removed. Furthermore, it will be also possible to use direct thermodynamic cycles where the supercritical fluid expands right away in a turbine without the necessity of using intermediate steam generators and/or separators. This work presents several thermodynamic cycles that could be appropriate to run SCWR power plants. Improving both thermal efficiency and mechanical power constitutes a multi-objective optimization problem and requires specific tools. To this aim, an efficient and robust evolutionary algorithm, based on genetic algorithm, is used and coupled to an appropriate power plant thermodynamic simulation model. The results provide numerous combinations to achieve a thermal efficiency higher than 50% with a mechanical power of 1200 MW. It is observed that in most cases the landscape of Pareto's front is mostly controlled only by few key parameters. These results may be very useful for future plant design engineers. Furthermore, some calculations for pipe sizing and temperature variation between coolant and fuel have been carried out to provide an idea on their order of magnitude.
Resource-Saving Cleaning Technologies for Power Plant Waste-Water Cooling Ponds
NASA Astrophysics Data System (ADS)
Zakonnova, Lyudmila; Nikishkin, Igor; Rostovzev, Alexandr
2017-11-01
One of the frequently encountered problems of power plant small cooling ponds is rapid eutrophication and related intensified development of phytoplankton ("hyperflow") and overgrowing of ponds by higher aquatic vegetation. As a result of hyper-flowering, an enormous amount of detritus settles on the condenser tubes, reducing the efficiency of the power plant operation. The development of higher aquatic vegetation contributes to the appearing of the shoals. As a result the volume, area and other characteristics of the cooling ponds are getting changed. The article describes the environmental problems of small manmade ponds of power plants and coal mines in mining regions. Two approaches to the problem of eutrophication are considered: technological and ecological. The negative effects of herbicides application to aquatic organisms are experimentally proved. An ecological approach to solving the problem by fish-land reclamation method is shown.
NASA Astrophysics Data System (ADS)
Veselov, F. V.; Novikova, T. V.; Khorshev, A. A.
2015-12-01
The paper focuses on economic aspects of the Russian thermal generation sector's renovation in a competitive market environment. Capabilities of the existing competitive electricity and capacity pricing mechanisms, created during the wholesale market reform, to ensure the wide-scale modernization of thermal power plants (TPPs) are estimated. Some additional stimulating measures to focus the investment process on the renovation of the thermal generation sector are formulated, and supplementing and supporting costs are assessed. Finally, the systemic effect of decelerating wholesale electricity prices caused by efficiency improvements at thermal power plants is analyzed depending on the scales of renovation and fuel prices.
Projected techno-economic improvements for advanced solar thermal power plants
NASA Technical Reports Server (NTRS)
Fujita, T.; Manvi, R.; Roschke, E. J.
1979-01-01
The projected characteristics of solar thermal power plants (with outputs up to 10 MWe) employing promising advanced technology subsystems/components are compared to current (or pre-1985) steam-Rankine systems. Improvements accruing to advanced technology development options are delineated. The improvements derived from advanced systems result primarily from achieving high efficiencies via solar collector systems which (1) capture a large portion of the available insolation and (2) concentrate this captured solar flux to attain high temperatures required for high heat engine/energy conversion performance. The most efficient solar collector systems employ two-axis tracking. Attractive systems include the central receiver/heliostat and the parabolic dish.
NASA Astrophysics Data System (ADS)
Miara, A.; Vorosmarty, C. J.; Stewart, R.; Wollheim, W. M.; Rosenzweig, B.
2013-12-01
Major strategic issues facing the global thermoelectric sector include environmental regulation, climate change and increasing electricity demand. We have addressed such issues by modeling thermoelectric generation in the Northeastern United States that is reliant on cooling under five sensitivity tests to evaluate losses/gains in power production, thermal pollution and suitable aquatic habitat, comparing the contemporary baseline (2000-2010) with potential future states. Integral to the analysis, we developed a methodology to quantify river water availability for cooling, which we define as an ecosystem service. Projected climate conditions reduce river water available for efficient power plant operations and the river's capacity to absorb waste heat, causing a loss of regional thermoelectric generation (RTG) (2.5%) in some summers that, compared to the contemporary baseline, is equal to the summertime electricity consumption of 1.3 million Northeastern US homes. Vulnerabilities to warm temperatures and thermal pollution can be alleviated through the use of more efficient natural gas (NG) power plants that have a reduced reliance on cooling water. Conversion of once-through (OT) to cooling tower (CT) systems and the Clean Water Act (CWA) temperature limit regulation, both of which reduce efficiencies at the single plant level, show potential to yield beneficial increases in RTG. This is achieved by obviating the need for large volumes of river water, thereby reducing plant-to-plant interferences through lowering the impact of upstream thermal pollution and preserving a minimum standard of cooling water. The results and methodology framework presented here, which can be extrapolated to other regional assessments with contrasting climates and thermoelectric profiles, can identify opportunities and support decision-making to achieve more efficient energy systems and riverine ecosystem protection.
NASA Astrophysics Data System (ADS)
Miara, Ariel; Vörösmarty, Charles J.; Stewart, Robert J.; Wollheim, Wilfred M.; Rosenzweig, Bernice
2013-06-01
Major strategic issues facing the global thermoelectric sector include environmental regulation, climate change and increasing electricity demand. We have addressed such issues by modeling thermoelectric generation in the Northeastern United States that is reliant on cooling under five sensitivity tests to evaluate losses/gains in power production, thermal pollution and suitable aquatic habitat, comparing the contemporary baseline (2000-2010) with potential future states. Integral to the analysis, we developed a methodology to quantify river water availability for cooling, which we define as an ecosystem service. Projected climate conditions reduce river water available for efficient power plant operations and the river’s capacity to absorb waste heat, causing a loss of regional thermoelectric generation (RTG) (2.5%) in some summers that, compared to the contemporary baseline, is equal to the summertime electricity consumption of 1.3 million Northeastern US homes. Vulnerabilities to warm temperatures and thermal pollution can be alleviated through the use of more efficient natural gas (NG) power plants that have a reduced reliance on cooling water. Conversion of once-through (OT) to cooling tower (CT) systems and the Clean Water Act (CWA) temperature limit regulation, both of which reduce efficiencies at the single plant level, show potential to yield beneficial increases in RTG. This is achieved by obviating the need for large volumes of river water, thereby reducing plant-to-plant interferences through lowering the impact of upstream thermal pollution and preserving a minimum standard of cooling water. The results and methodology framework presented here, which can be extrapolated to other regional assessments with contrasting climates and thermoelectric profiles, can identify opportunities and support decision-making to achieve more efficient energy systems and riverine ecosystem protection.
Bin, Hu; Yang, Yi; Cai, Liang; Yang, Linjun; Roszak, Szczepan
2017-10-09
Desulfurization wastewater evaporation technology is used to enhance the removal of gaseous mercury (Hg) in conventional air pollution control devices (APCDs) for coal-fired power plants. Studies have affirmed that gaseous Hg is oxidized and removed by selective catalytic reduction (SCR), an electrostatic precipitator (ESP) and wet flue gas desulfurization (WFGD) in a coal-fired thermal experiment platform with WFGD wastewater evaporation. Effects of desulfurization wastewater evaporation position, evaporation temperature and chlorine ion concentration on Hg oxidation were studied as well. The Hg 0 oxidation efficiency was increased ranging from 30% to 60%, and the gaseous Hg removal efficiency was 62.16% in APCDs when wastewater evaporated before SCR. However, the Hg 0 oxidation efficiency was 18.99% and the gaseous Hg removal efficiency was 40.19% in APCDs when wastewater evaporated before ESP. The results show that WFGD wastewater evaporation before SCR is beneficial to improve the efficiency of Hg oxidized and removed in APCDs. Because Hg 2+ can be easily removed in ACPDs and WFGD wastewater in power plants is enriched with chlorine ions, this method realizes WFGD wastewater zero discharge and simultaneously enhances Hg removal in APCDs.
NASA Astrophysics Data System (ADS)
Welaya, Yousri M. A.; Mosleh, M.; Ammar, Nader R.
2013-12-01
Strong restrictions on emissions from marine power plants (particularly SO x , NO x ) will probably be adopted in the near future. In this paper, a combined solid oxide fuel cell (SOFC) and steam turbine fuelled by natural gas is proposed as an attractive option to limit the environmental impact of the marine sector. The analyzed variant of the combined cycle includes a SOFC operated with natural gas fuel and a steam turbine with a single-pressure waste heat boiler. The calculations were performed for two types of tubular and planar SOFCs, each with an output power of 18 MW. This paper includes a detailed energy analysis of the combined system. Mass and energy balances are performed not only for the whole plant but also for each component in order to evaluate the thermal efficiency of the combined cycle. In addition, the effects of using natural gas as a fuel on the fuel cell voltage and performance are investigated. It has been found that a high overall efficiency approaching 60% may be achieved with an optimum configuration using the SOFC system. The hybrid system would also reduce emissions, fuel consumption, and improve the total system efficiency.
Effectiveness of state climate and energy policies in reducing power-sector CO2 emissions
NASA Astrophysics Data System (ADS)
Martin, Geoff; Saikawa, Eri
2017-12-01
States have historically been the primary drivers of climate change policy in the US, particularly with regard to emissions from power plants. States have implemented policies designed either to directly curb greenhouse gas (GHG) emissions from power plants, or to encourage energy efficiency and renewable energy growth. With the federal government withdrawing from the global climate agreement, understanding which state-level policies have successfully mitigated power-plant emissions is urgent. Past research has assessed policy effectiveness using data for periods before the adoption of many policies. We assess 17 policies using the latest data on state-level power-sector CO2 emissions. We find that policies with mandatory compliance are reducing power-plant emissions, while voluntary policies are not. Electric decoupling, mandatory GHG registry/reporting and public benefit funds are associated with the largest reduction in emissions. Mandatory GHG registry/reporting and public benefit funds are also associated with a large reduction in emissions intensity.
The simulation of organic rankine cycle power plant with n-pentane working fluid
NASA Astrophysics Data System (ADS)
Nurhilal, Otong; Mulyana, Cukup; Suhendi, Nendi; Sapdiana, Didi
2016-02-01
In the steam power plant in Indonesia the dry steam from separator directly used to drive the turbin. Meanwhile, brine from the separator with low grade temperature reinjected to the earth. The brine with low grade temperature can be converted indirectly to electrical power by organic Rankine cycle (ORC) methods. In ORC power plant the steam are released from vaporization of organic working fluid by brine. The steam released are used to drive an turbine which in connected to generator to convert the mechanical energy into electric energy. The objective of this research is the simulation ORC power plant with n-pentane as organic working fluid. The result of the simulation for brine temperature around 165°C and the pressure 8.001 bar optained the net electric power around 1173 kW with the cycle thermal efficiency 14.61% and the flow rate of n-pentane around 15.51 kg/s. This result enable to applied in any geothermal source in Indonesia.
Mohamed, Omar; Wang, Jihong; Khalil, Ashraf; Limhabrash, Marwan
2016-01-01
This paper presents a novel strategy for implementing model predictive control (MPC) to a large gas turbine power plant as a part of our research progress in order to improve plant thermal efficiency and load-frequency control performance. A generalized state space model for a large gas turbine covering the whole steady operational range is designed according to subspace identification method with closed loop data as input to the identification algorithm. Then the model is used in developing a MPC and integrated into the plant existing control strategy. The strategy principle is based on feeding the reference signals of the pilot valve, natural gas valve, and the compressor pressure ratio controller with the optimized decisions given by the MPC instead of direct application of the control signals. If the set points for the compressor controller and turbine valves are sent in a timely manner, there will be more kinetic energy in the plant to release faster responses on the output and the overall system efficiency is improved. Simulation results have illustrated the feasibility of the proposed application that has achieved significant improvement in the frequency variations and load following capability which are also translated to be improvements in the overall combined cycle thermal efficiency of around 1.1 % compared to the existing one.
NASA Technical Reports Server (NTRS)
Brown, Dale H.
1976-01-01
A study was performed to estimate the technical/economic characteristics of a steam power plant (3500 pounds per square inch gauge, 1000 degrees Fahrenheit / 1000 degrees Fahrenheit) with a coal-burning radiant furnace and a wet lime stack gas scrubber to control sulfur emissions. Particulate emissions were controlled by an electrostatic precipitator operating at 300 degrees Fahrenheit. The stack gas from the scrubber was reheated from 125 degrees Fahrenheit to 250 degrees Fahrenheit as a base case, and from 125 degrees Fahrenheit to 175 degrees Fahrenheit as an alternate case. The study was performed on a basis consistent with the General Electric ECAS Phase II evaluation of advanced energy conversion systems for electric utility baseload applications using coal or coal-derived fuels. A conceptual design of the power plant was developed, including the on-site calcination of limestone to lime and the provision of sludge ponds to store the products of flue gas scrubbing. From this design, estimates were derived for power plant efficiency, capital cost, environmental intrusion characteristics, natural resource requirements, and cost of electricity at an assumed capacity factor of 65 percent. An implementation assessment was performed where factors affecting applicability of the conceptual design power plant in electric utility generation systems were appraised. At 250 degrees Fahrenheit and 175 degrees Fahrenheit stack gas temperatures respectively, the plants showed a cost of electricity of 39.8 and 37.0 mills per kilowatt-hours and overall plant efficiencies of 32 percent and 34 percent.
Economies of scale and asset values in power production
DOE Office of Scientific and Technical Information (OSTI.GOV)
Considine, T.J.
While innovative trading tools have become an increasingly important aspect of the electricity business, the future of any firm in the industry boils down to a basic bread and butter issue of generating power at competitive costs. While buying electricity from power pools at spot prices instead of generating power to service load may be profitable for some firms in the short run, the need to efficiently utilize existing plants in the long run remains. These competitive forces will force the closure of many inefficient plants. As firms close plants and re-evaluate their generating asset portfolios, the basic structure ofmore » the industry will change. This article presents some quantitative analysis that sheds light on this unfolding transformation.« less
Integrated power sector efficiency analysis: A case study of Costa Rica
DOE Office of Scientific and Technical Information (OSTI.GOV)
Waddle, D.B.; MacDonald, J.M.
1990-03-01
In an effort to analyze and document the potential for power sector efficiency improvements from generation to end-use, the Agency for International Development and the Government of Costa Rica are jointly conducting an integrated power sector efficiency analysis. Potential for energy and cost savings in power plants, transmission and distribution, and demand-side management programs are being evaluated. The product of this study will be an integrated investment plan for the Instituto Costarricense de Electricidad, incorporating both supply and demand side investment options. This paper presents the methodology employed in the study, as well as preliminary estimates of the results ofmore » the study. 14 refs., 2 figs., 5 tabs.« less
NASA Astrophysics Data System (ADS)
Saar, Martin; Garapati, Nagasree; Adams, Benjamin; Randolph, Jimmy; Kuehn, Thomas
2016-04-01
Safe, sustainable, and economic development of deep geothermal resources, particularly in less favourable regions, often requires employment of unconventional geothermal energy extraction and utilization methods. Often "unconventional geothermal methods" is synonymously and solely used as meaning enhanced geothermal systems, where the permeability of hot, dry rock with naturally low permeability at greater depths (4-6 km), is enhanced. Here we present an alternative unconventional geothermal energy utilization approach that uses low-temperature regions that are shallower, thereby drastically reducing drilling costs. While not a pure geothermal energy system, this hybrid approach may enable utilization of geothermal energy in many regions worldwide that can otherwise not be used for geothermal electricity generation, thereby increasing the global geothermal resource base. Moreover, in some realizations of this hybrid approach that generate carbon dioxide (CO2), the technology may be combined with carbon dioxide capture and storage (CCS) and CO2-based geothermal energy utilization, resulting in a high-efficiency (hybrid) geothermal power plant with a negative carbon footprint. Typically, low- to moderate-temperature geothermal resources are more effectively used for direct heat energy applications. However, due to high thermal losses during transport, direct use requires that the heat resource is located near the user. Alternatively, we show here that if such a low-temperature geothermal resource is combined with an additional or secondary energy resource, the power production is increased compared to the sum from two separate (geothermal and secondary fuel) power plants (DiPippo et al. 1978) and the thermal losses are minimized because the thermal energy is utilized where it is produced. Since Adams et al. (2015) found that using CO2 as a subsurface working fluid produces more net power than brine at low- to moderate-temperature geothermal resource conditions, we compare over a range of parameters the net power and efficiencies of hybrid geothermal power plants that use brine or CO2 as the subsurface working fluid, that are then heated further with a secondary energy source that is unspecified here. Parameters varied include the subsurface working fluid (brine vs. CO2), geothermal reservoir depth (2.5-4.5 km), and turbine inlet temperature (200-600°C) after auxiliary heating. The hybrid power plant is numerically modeled using an iterative coupling approach of TOUGH2-ECO2N/ECO2H (Pruess, 2004) for simulation of the subsurface reservoir and Engineering Equation Solver for well bore fluid flow and surface power plant performance. We find that hybrid power plants that are CO2-based (subsurface) systems produce more net power than the sum of the power produced by individual power plants at low turbine inlet temperatures and brine based systems produce more power at high turbine inlet temperatures. Specifically, our results indicate that geothermal hybrid plants that are CO2-based are more efficient than brine-based systems when the contribution of the geothermal resource energy is higher than 48%.
USDA-ARS?s Scientific Manuscript database
Citrus propagation by conventional means is restricted to particular season and availability of plant material. It doesn’t guarantee trueness of cultivars and mass production of certified Citrus plants throughout the year. Plant tissue culture has emerged as a powerful tool to propagation and improv...
Liquid-metal magnetohydrodynamic system evaluation. [coal-fired designs
NASA Technical Reports Server (NTRS)
Holman, R. R.; Lippert, T. E.
1976-01-01
The present study emphasizes a direct coal-fired design using a bubbly two-component flow of sodium and argon in the MHD generator and a Rankine steam-bottoming plant. Two basic cycles were studied, corresponding to argon temperatures of 922 and 1089 K at the duct inlet. The MHD duct system consisted of multiple ducts arranged in clusters and separated by iron magnet pole pieces. The ducts, each with an output of about 100 MW, were parallel to the flow, but were connected in series electrically to provide a higher MHD voltage. With channel efficiencies of 80%, a pump efficiency of 90%, and a 45% efficient steam-bottoming plant, the overall efficiency of the 1089 K liquid-metal MHD power plant was 43%.
Noncombatant Evacuation Operations (NEO) Decision-Making Process Effects on Efficiency
2012-02-15
the eastern coast of Japan. On 12 March, the Fukushima Daiichi nuclear power plant experienced explosions and fires within four reactors.51 Over... awareness , and understanding the mission objectives.43 The following outlines recent NEO successes and failures. First, a strategic look at the evacuation... Daiichi nuclear power plant. Over the next 30 days, the JTF and embassy worked intensely to develop a comprehensive plan overcoming many of the
d'Entremont, Anna; Corgnale, Claudio; Hardy, Bruce; ...
2018-01-11
Concentrating solar power plants can achieve low cost and efficient renewable electricity production if equipped with adequate thermal energy storage systems. Metal hydride based thermal energy storage systems are appealing candidates due to their demonstrated potential for very high volumetric energy densities, high exergetic efficiencies, and low costs. The feasibility and performance of a thermal energy storage system based on NaMgH 2F hydride paired with TiCr 1.6Mn 0.2 is examined, discussing its integration with a solar-driven ultra-supercritical steam power plant. The simulated storage system is based on a laboratory-scale experimental apparatus. It is analyzed using a detailed transport model accountingmore » for the thermochemical hydrogen absorption and desorption reactions, including kinetics expressions adequate for the current metal hydride system. The results show that the proposed metal hydride pair can suitably be integrated with a high temperature steam power plant. The thermal energy storage system achieves output energy densities of 226 kWh/m 3, 9 times the DOE SunShot target, with moderate temperature and pressure swings. Also, simulations indicate that there is significant scope for performance improvement via heat-transfer enhancement strategies.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
d'Entremont, Anna; Corgnale, Claudio; Hardy, Bruce
Concentrating solar power plants can achieve low cost and efficient renewable electricity production if equipped with adequate thermal energy storage systems. Metal hydride based thermal energy storage systems are appealing candidates due to their demonstrated potential for very high volumetric energy densities, high exergetic efficiencies, and low costs. The feasibility and performance of a thermal energy storage system based on NaMgH 2F hydride paired with TiCr 1.6Mn 0.2 is examined, discussing its integration with a solar-driven ultra-supercritical steam power plant. The simulated storage system is based on a laboratory-scale experimental apparatus. It is analyzed using a detailed transport model accountingmore » for the thermochemical hydrogen absorption and desorption reactions, including kinetics expressions adequate for the current metal hydride system. The results show that the proposed metal hydride pair can suitably be integrated with a high temperature steam power plant. The thermal energy storage system achieves output energy densities of 226 kWh/m 3, 9 times the DOE SunShot target, with moderate temperature and pressure swings. Also, simulations indicate that there is significant scope for performance improvement via heat-transfer enhancement strategies.« less
NASA Astrophysics Data System (ADS)
Mousavi, Seyed Hosein; Nazemi, Ali; Hafezalkotob, Ashkan
2016-09-01
With the increasing use of different types of auctions in market designing, modeling of participants' behaviors to evaluate the market structure is one of the main discussions in the studies related to the deregulated power industries. In this article, we apply an approach of the optimal bidding behavior to the Iran wholesale electricity market as a restructured electric power industry and model how the participants of the market bid in the spot electricity market. The problem is formulated analytically using the Nash equilibrium concept composed of large numbers of players having discrete and very large strategy spaces. Then, we compute and draw supply curve of the competitive market in which all generators' proposed prices are equal to their marginal costs and supply curve of the real market in which the pricing mechanism is pay-as-bid. We finally calculate the lost welfare or inefficiency of the Nash equilibrium and the real market by comparing their supply curves with the competitive curve. We examine 3 cases on November 24 (2 cases) and July 24 (1 case), 2012. It is observed that in the Nash equilibrium on November 24 and demand of 23,487 MW, there are 212 allowed plants for the first case (plants are allowed to choose any quantity of generation except one of them that should be equal to maximum Power) and the economic efficiency or social welfare of Nash equilibrium is 2.77 times as much as the real market. In addition, there are 184 allowed plants for the second case (plants should offer their maximum power with different prices) and the efficiency or social welfare of Nash equilibrium is 3.6 times as much as the real market. On July 24 and demand of 42,421 MW, all 370 plants should generate maximum energy due to the high electricity demand that the economic efficiency or social welfare of the Nash equilibrium is about 2 times as much as the real market.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Goodson, J.O.
This is the first of three volumes which document the historical development of the first US compressed-air energy storage (CAES) Power-generation facility. Volume 1 is a background report and presents a chronicle of the development of the CAES facility from the early interest in CAES until inception of engineering/construction on August 11, 1988. The 110 MW - 26 hr CAES plant is owned and operated by Alabama Electric Cooperative, Inc. (AEC) of Andalusia, Alabama. The plant is the first CAES plant in the United States and the world's first CAES facility incorporating a recuperator to improve efficiency. The plant suppliesmore » competitively priced peaking power to the AEC owner members. The economics of CAES-produced power is attractive because the energy-intensive air-compression mode is powered by relatively inexpensive base-load power external to the CAES plant. The compressed-air energy is stored underground until needed, and during the power-production mode, the only fuel required is that to heat the compressed air to expander-inlet temperature. The project development for AEC's CAES plant involved much planning and preliminary design work. Specifically, this included load and generation-planning studies, power-supply selections, conceptual designs, project administration, air-storage cavern and turbomachinery specifications and design, contract requirements, environmental and licensing issues, and construction planning.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Goodson, J.O.
This is the first of three volumes which document the historical development of the first US compressed-air energy storage (CAES) Power-generation facility. Volume 1 is a background report and presents a chronicle of the development of the CAES facility from the early interest in CAES until inception of engineering/construction on August 11, 1988. The 110 MW - 26 hr CAES plant is owned and operated by Alabama Electric Cooperative, Inc. (AEC) of Andalusia, Alabama. The plant is the first CAES plant in the United States and the world`s first CAES facility incorporating a recuperator to improve efficiency. The plant suppliesmore » competitively priced peaking power to the AEC owner members. The economics of CAES-produced power is attractive because the energy-intensive air-compression mode is powered by relatively inexpensive base-load power external to the CAES plant. The compressed-air energy is stored underground until needed, and during the power-production mode, the only fuel required is that to heat the compressed air to expander-inlet temperature. The project development for AEC`s CAES plant involved much planning and preliminary design work. Specifically, this included load and generation-planning studies, power-supply selections, conceptual designs, project administration, air-storage cavern and turbomachinery specifications and design, contract requirements, environmental and licensing issues, and construction planning.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Phadke, Amol; Abhyankar, Nikit; Shah, Nihar
Electricity demand for room ACs is growing very rapidly in emerging economies such as India. We estimate the electricity demand from room ACs in 2030 in India considering factors such as weather and income growth using market data on penetration of ACs in different income classes and climatic regions. We discuss the status of the current standards, labels, and incentive programs to improve the efficiency of room ACs in these markets and assess the potential for further large improvements in efficiency and find that efficiency can be improved by over 40% cost effectively. The total potential energy savings from Roommore » AC efficiency improvement in India using the best available technology will reach over 118 TWh in 2030; potential peak demand saving is found to be 60 GW by 2030. This is equivalent to avoiding 120 new coal fired power plants of 500 MW each. We discuss policy options to complement, expand and improve the ongoing programs to capture this large potential.« less
Pressure pulsations and hydraulic efficiency at Smeland power plant
NASA Astrophysics Data System (ADS)
Ulvan, V. S.; Kverno, J. O.; Dahlhaug, O. G.
2018-06-01
Smeland power plant in Norway is experiencing pressure pulsations in their Francis turbine when running above best efficiency point. By measuring both the pressure pulsations and runner efficiency, the cause and effect of the pulsations are to be investigated thoroughly, which is this works main purpose. To find the Francis runners efficiency the thermodynamic method has been used, which builds on the principle that all of the hydraulic losses turns into heat in the flow itself. By measuring the change of temperature before and after the turbine one can, with little other data, calculate the hydraulic efficiency. To identify the pressure pulsations, pressure transducers were placed on the inlet to the spiral casing, draft tube, and upper labyrinth. While doing measurements, air-injection through the runner was tested on full load, which nearly eradicated the pressure pulsations. This might be due to an increase of volume in a pulsating full load vortex that changed its eigenfrequency, and therefore stopped resonating.
NASA Astrophysics Data System (ADS)
Yeo, M. J.; Kim, Y. P.
2017-12-01
Recently, concerns about the atmospheric environmental problems in North Korea (NK) have been growing. According to the World Health Organization (WHO) (2017), NK was the first ranked country in mortality rate attributed to household and ambient air pollution in 2012. Reliable energy-related data in NK were needed to understand the characteristics of air quality in NK. However, data from the North Korean government were limited. Nevertheless, we could find specific energy-related data produced by NK in the Project Design Documents (PDDs) of the Clean Development Mechanism (CDM) submitted to the United Nations Framework Convention on Climate Change (UNFCCC). There were the 6 registered CDM projects hosted by North Korea, developed as small hydropower plants. Several data of each power plant, such as the electricity output, connected to the Eastern Power Grid (EPG) or the Western Power Grid (WPG) in North Korea were provided in the CDM PDDs. We (1) figured out the trends of the electricity output, the `power conversion efficiency' which we defined the amount of generated electricity to the supplied input primary energy for power generation, and fuel mix as grid emission factor in NK as using the data produced by NK between 2005 and 2009, (2) discussed the operating status of the thermal power plants in NK, and (3) discussed the energy/environmental-related policies and the priority issues in NK in this study.
A summary of the ECAS MHD power plant results
NASA Technical Reports Server (NTRS)
Seikel, G. R.; Harris, L. P.
1976-01-01
The performance and the cost of electricity (COE) for MHD systems utilizing coal or coal derived fuels are summarized along with a conceptual open cycle MHD plant design. The results show that open cycle coal fired recuperatively preheated MHD systems have potentially one of the highest coal-pile-to-bus bar efficiencies (48.3%) and also one of the lowest COE of the systems studied. Closed cycle, inert gas systems do not appear to have the potential of exceeding the efficiency of or competing with the COE of advanced steam plants.
Performance analysis and optimization of power plants with gas turbines
NASA Astrophysics Data System (ADS)
Besharati-Givi, Maryam
The gas turbine is one of the most important applications for power generation. The purpose of this research is performance analysis and optimization of power plants by using different design systems at different operation conditions. In this research, accurate efficiency calculation and finding optimum values of efficiency for design of chiller inlet cooling and blade cooled gas turbine are investigated. This research shows how it is possible to find the optimum design for different operation conditions, like ambient temperature, relative humidity, turbine inlet temperature, and compressor pressure ratio. The simulated designs include the chiller, with varied COP and fogging cooling for a compressor. In addition, the overall thermal efficiency is improved by adding some design systems like reheat and regenerative heating. The other goal of this research focuses on the blade-cooled gas turbine for higher turbine inlet temperature, and consequently, higher efficiency. New film cooling equations, along with changing film cooling effectiveness for optimum cooling air requirement at the first-stage blades, and an internal and trailing edge cooling for the second stage, are innovated for optimal efficiency calculation. This research sets the groundwork for using the optimum value of efficiency calculation, while using inlet cooling and blade cooling designs. In the final step, the designed systems in the gas cycles are combined with a steam cycle for performance improvement.
Flexible operation of thermal plants with integrated energy storage technologies
NASA Astrophysics Data System (ADS)
Koytsoumpa, Efthymia Ioanna; Bergins, Christian; Kakaras, Emmanouil
2017-08-01
The energy system in the EU requires today as well as towards 2030 to 2050 significant amounts of thermal power plants in combination with the continuously increasing share of Renewables Energy Sources (RES) to assure the grid stability and to secure electricity supply as well as to provide heat. The operation of the conventional fleet should be harmonised with the fluctuating renewable energy sources and their intermittent electricity production. Flexible thermal plants should be able to reach their lowest minimum load capabilities while keeping the efficiency drop moderate as well as to increase their ramp up and down rates. A novel approach for integrating energy storage as an evolutionary measure to overcome many of the challenges, which arise from increasing RES and balancing with thermal power is presented. Energy storage technologies such as Power to Fuel, Liquid Air Energy Storage and Batteries are investigated in conjunction with flexible power plants.
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.
Efficiencies of power plants, quasi-static models and the geometric-mean temperature
NASA Astrophysics Data System (ADS)
Johal, Ramandeep S.
2017-02-01
Observed efficiencies of industrial power plants are often approximated by the square-root formula: 1 - √ T -/ T +, where T +( T -) is the highest (lowest) temperature achieved in the plant. This expression can be derived within finite-time thermodynamics, or, by entropy generation minimization, based on finite rates for the processes. In these analyses, a closely related quantity is the optimal value of the intermediate temperature for the hot stream, given by the geometric-mean value: √ T +/ T -. In this paper, instead of finite-time models, we propose to model the operation of plants by quasi-static work extraction models, with one reservoir (source/sink) as finite, while the other as practically infinite. No simplifying assumption is made on the nature of the finite system. This description is consistent with two model hypotheses, each yielding a specific value of the intermediate temperature, say T 1 and T 2. The lack of additional information on validity of the hypothesis that may be actually realized, motivates to approach the problem as an exercise in inductive inference. Thus we define an expected value of the intermediate temperature as the equally weighted mean: ( T 1 + T 2)/2. It is shown that the expected value is very closely given by the geometric-mean value for almost all of the observed power plants.
Energy regeneration model of self-consistent field of electron beams into electric power*
NASA Astrophysics Data System (ADS)
Kazmin, B. N.; Ryzhov, D. R.; Trifanov, I. V.; Snezhko, A. A.; Savelyeva, M. V.
2016-04-01
We consider physic-mathematical models of electric processes in electron beams, conversion of beam parameters into electric power values and their transformation into users’ electric power grid (onboard spacecraft network). We perform computer simulation validating high energy efficiency of the studied processes to be applied in the electric power technology to produce the power as well as electric power plants and propulsion installation in the spacecraft.
General fuel cell hybrid synergies and hybrid system testing status
NASA Astrophysics Data System (ADS)
Winkler, Wolfgang; Nehter, Pedro; Williams, Mark C.; Tucker, David; Gemmen, Randy
FCT hybrid power systems offer the highest efficiency and the cleanest emissions of all fossil fuelled power. The engineering for the highest possible efficiency at lowest cost and weight depends on general system architecture issues and the performance of the components. Presented in this paper are system studies which provide direction for the most efficient path toward achieving the most beneficial result for this technology. Ultimately, fuel cell-turbine (FCT) hybrid systems applicable to integrated gasification combined cycle power systems will form the basis for reaching the goals for advanced coal-based power generation. The FCT hybrid power island will also be important for the FutureGen plant and will provide new options for carbon dioxide capture and sequestration as well as power and hydrogen generation. The system studies presented in this paper provide insight to current technology 'benchmarks' versus expected benefits from hybrid applications. Discussion is also presented on the effects of different balance of plant arrangements and approaches. Finally, we discuss the status of US DOE is sponsored projects that are looking to help understand the unique requirements for these systems. One of these projects, Hyper, will provide information on FCT dynamics and will help identify technical needs and opportunities for cycle advancement. The methods studied show promise for effective control of a hybrid system without the direct intervention of isolation valves or check valves in the main pressure loop of the system, which introduce substantial pressure losses, allowing for realization of the full potential efficiency of the hybrid system.
A Technical Feasibility Study of a Green Area
2012-09-01
40 Biomass Gasification Combined Cycle 40 Waste-to-Electricity 22 - 28 Nuclear 33 - 36 Table 21. Power Plants Efficiencies. After [17] 71 VI...10 6. Biomass and Biofuels ........................................................... 11 7. Earthquakes...31 5. Tidal Power ............................................................................. 32 6. Biomass and Biofuels
Benefits of full scope simulators during solar thermal power plants design and construction
NASA Astrophysics Data System (ADS)
Gallego, José F.; Gil, Elena; Rey, Pablo
2017-06-01
In order to efficiently develop high-precision dynamic simulators for solar thermal power plants, Tecnatom adapted its simulation technology to consider solar thermal models. This effort and the excellent response of the simulation market have allowed Tecnatom to develop simulators with both parabolic trough and solar power tower technologies, including molten salt energy storage. These simulators may pursue different objectives, giving rise to training or engineering simulators. Solar thermal power market combines the need for the training of the operators with the potential benefits associated to the improvement of the design of the plants. This fact along with the simulation capabilities enabled by the current technology and the broad experience of Tecnatom present the development of an engineering+training simulator as a very advantageous option. This paper describes the challenge of the development and integration of a full scope simulator during the design and construction stages of a solar thermal power plant, showing the added value to the different engineering areas.
NASA Astrophysics Data System (ADS)
Leucht, Florian; Bessler, Wolfgang G.; Kallo, Josef; Friedrich, K. Andreas; Müller-Steinhagen, H.
A sustainable future power supply requires high fuel-to-electricity conversion efficiencies even in small-scale power plants. A promising technology to reach this goal is a hybrid power plant in which a gas turbine (GT) is coupled with a solid oxide fuel cell (SOFC). This paper presents a dynamic model of a pressurized SOFC system consisting of the fuel cell stack with combustion zone and balance-of-plant components such as desulphurization, humidification, reformer, ejector and heat exchangers. The model includes thermal coupling between the different components. A number of control loops for fuel and air flows as well as power management are integrated in order to keep the system within the desired operation window. Models and controls are implemented in a MATLAB/SIMULINK environment. Different hybrid cycles proposed earlier are discussed and a preferred cycle is developed. Simulation results show the prospects of the developed modeling and control system.
Modern process designs for very high NGL recovery
DOE Office of Scientific and Technical Information (OSTI.GOV)
Finn, A.J.; Tomlinson, T.R.; Johnson, G.L.
1999-07-01
Typical margins between NGL and sales gas can justify consideration of very high NGL recovery from natural gas but traditionally, very high percentage recovery of propane or ethane has led to disproportionally high incremental power consumption and hence expensive compressors. Recent technical advances in the process design of cryogenic gas processing plants and in the equipment they se have led to a new breed of flowsheets that can cost-effectively give propane recoveries of as high as 99%. The high NGL recovery achievable with modern plants is economically possible due to their high thermodynamic efficiency. This is mainly because they usemore » the refrigeration available from the process more effectively and so recover more NGL. A high pressure rectification step can further improve NGL recovery economically, especially on larger plants. This residual NGL content would normally remain in the sales gas on a conventional turboexpander plant. Improved recovery of NGL can be obtained with little or no increase in sales gas compression power compared to conventional plants by judicious use of heat exchanger area. With high feed gas pressure and particularly with dense phase operation, the use of two expanders in series for feed gas let-down gives good process efficiency and relatively low specific power per ton of NGL recovered. Use of two expanders also avoids excessive liquid flows in the expander exhaust, thus improving the performance and reliability of the turboexpander system. The techniques discussed in the paper can be employed on revamps to improve NGL recovery. Improved process performance relies heavily on the use of efficient, multistream plant-fin exchangers and these can be easily added to an existing facility to increase NGL production.« less
NASA Astrophysics Data System (ADS)
Azharuddin; Santarelli, Massimo
2016-09-01
Thermodynamic analysis of a closed cycle, solar powered Brayton gas turbine power plant with Concentrating Receiver system has been studied. A Brayton cycle is simpler than a Rankine cycle and has an advantage where the water is scarce. With the normal Brayton cycle a Concentrating Receiver System has been analysed which has a dependence on field density and optical system. This study presents a method of optimization of design parameter, such as the receiver working temperature and the heliostats density. This method aims at maximizing the overall efficiency of the three major subsystem that constitute the entire plant, namely, the heliostat field and the tower, the receiver and the power block. The results of the optimization process are shown and analysed.
Combined Cycle Power Generation Employing Pressure Gain Combustion
DOE Office of Scientific and Technical Information (OSTI.GOV)
Holley, Adam
The Phase I program assessed the potential benefit of applying pressure gain combustion (PGC) technology to a natural gas combined cycle power plant. A conceptual design of the PGC integrated gas turbine was generated which was simulated in a detailed system modeling tool. The PGC integrated system was 1.93% more efficient, produced 3.09% more power, and reduced COE by 0.58%. Since the PGC system used had the same fuel flow rate as the baseline system, it also reduced CO 2 emissions by 3.09%. The PGC system did produce more NOx than standard systems, but even with the performanceand cost penaltiesmore » associated with the cleanup system it is better in every measure. This technology benefits all of DOE’s stated program goals to improve plant efficiency, reduce CO 2 production, and reduce COE.« less
Removal of Iron Oxide Scale from Feed-water in Thermal Power Plant by Using Magnetic Separation
NASA Astrophysics Data System (ADS)
Nakanishi, Motohiro; Shibatani, Saori; Mishima, Fumihito; Akiyama, Yoko; Nishijima, Shigehiro
2017-09-01
One of the factors of deterioration in thermal power generation efficiency is adhesion of the scale to inner wall in feed-water system. Though thermal power plants have employed All Volatile Treatment (AVT) or Oxygen Treatment (OT) to prevent scale formation, these treatments cannot prevent it completely. In order to remove iron oxide scale, we proposed magnetic separation system using solenoidal superconducting magnet. Magnetic separation efficiency is influenced by component and morphology of scale which changes their property depending on the type of water treatment and temperature. In this study, we estimated component and morphology of iron oxide scale at each equipment in the feed-water system by analyzing simulated scale generated in the pressure vessel at 320 K to 550 K. Based on the results, we considered installation sites of the magnetic separation system.
NASA Astrophysics Data System (ADS)
Králik, Juraj
2017-07-01
The paper presents the probabilistic and sensitivity analysis of the efficiency of the damping devices cover of nuclear power plant under impact of the container of nuclear fuel of type TK C30 drop. The finite element idealization of nuclear power plant structure is used in space. The steel pipe damper system is proposed for dissipation of the kinetic energy of the container free fall. The experimental results of the shock-damper basic element behavior under impact loads are presented. The Newmark integration method is used for solution of the dynamic equations. The sensitivity and probabilistic analysis of damping devices was realized in the AntHILL and ANSYS software.
The design of photovoltaic plants - An optimization procedure
NASA Astrophysics Data System (ADS)
Bartoli, B.; Cuomo, V.; Fontana, F.; Serio, C.; Silvestrini, V.
An analytical model is developed to match the components and overall size of a solar power facility (comprising photovoltaic array), maximum-power tracker, battery storage system, and inverter) to the load requirements and climatic conditions of a proposed site at the smallest possible cost. Input parameters are the efficiencies and unit costs of the components, the load fraction to be covered (for stand-alone systems), the statistically analyzed meteorological data, and the cost and efficiency data of the support system (for fuel-generator-assisted plants). Numerical results are presented in graphs and tables for sites in Italy, and it is found that the explicit form of the model equation is independent of locality, at least for this region.
NASA Technical Reports Server (NTRS)
Marston, C. H.; Alyea, F. N.; Bender, D. J.; Davis, L. K.; Dellinger, T. C.; Hnat, J. G.; Komito, E. H.; Peterson, C. A.; Rogers, D. A.; Roman, A. J.
1980-01-01
The performance and cost of moderate technology coal-fired open cycle MHD/steam power plant designs which can be expected to require a shorter development time and have a lower development cost than previously considered mature OCMHD/steam plants were determined. Three base cases were considered: an indirectly-fired high temperature air heater (HTAH) subsystem delivering air at 2700 F, fired by a state of the art atmospheric pressure gasifier, and the HTAH subsystem was deleted and oxygen enrichment was used to obtain requisite MHD combustion temperature. Coal pile to bus bar efficiencies in ease case 1 ranged from 41.4% to 42.9%, and cost of electricity (COE) was highest of the three base cases. For base case 2 the efficiency range was 42.0% to 45.6%, and COE was lowest. For base case 3 the efficiency range was 42.9% to 44.4%, and COE was intermediate. The best parametric cases in bases cases 2 and 3 are recommended for conceptual design. Eventual choice between these approaches is dependent on further evaluation of the tradeoffs among HTAH development risk, O2 plant integration, and further refinements of comparative costs.
Optical study of solar tower power plants
NASA Astrophysics Data System (ADS)
Eddhibi, F.; Ben Amara, M.; Balghouthi, M.; Guizani, A.
2015-04-01
The central receiver technology for electricity generation consists of concentrating solar radiation coming from the solar tracker field into a central receiver surface located on the top of the tower. The heliostat field is constituted of a big number of reflective mirrors; each heliostat tracks the sun individually and reflects the sunlight to a focal point. Therefore, the heliostat should be positioned with high precision in order to minimize optical losses. In the current work, a mathematical model for the analysis of the optical efficiency of solar tower field power plant is proposed. The impact of the different factors which influence the optical efficiency is analyzed. These parameters are mainly, the shading and blocking losses, the cosine effect, the atmospheric attenuation and the spillage losses. A new method for the calculation of blocking and shadowing efficiency is introduced and validated by open literature.
Optimal PGU operation strategy in CHP systems
NASA Astrophysics Data System (ADS)
Yun, Kyungtae
Traditional power plants only utilize about 30 percent of the primary energy that they consume, and the rest of the energy is usually wasted in the process of generating or transmitting electricity. On-site and near-site power generation has been considered by business, labor, and environmental groups to improve the efficiency and the reliability of power generation. Combined heat and power (CHP) systems are a promising alternative to traditional power plants because of the high efficiency and low CO2 emission achieved by recovering waste thermal energy produced during power generation. A CHP operational algorithm designed to optimize operational costs must be relatively simple to implement in practice such as to minimize the computational requirements from the hardware to be installed. This dissertation focuses on the following aspects pertaining the design of a practical CHP operational algorithm designed to minimize the operational costs: (a) real-time CHP operational strategy using a hierarchical optimization algorithm; (b) analytic solutions for cost-optimal power generation unit operation in CHP Systems; (c) modeling of reciprocating internal combustion engines for power generation and heat recovery; (d) an easy to implement, effective, and reliable hourly building load prediction algorithm.
Hydrogen by electrolysis of water
NASA Technical Reports Server (NTRS)
1975-01-01
Hydrogen production by electrolytic decomposition of water is explained. Power efficiency, efficient energy utilization, and costs were emphasized. Four systems were considered: two were based on current electrolyzer technology using present efficiency values for electrical generation by fossil fired and nuclear thermal stations, and two using projected electrolyzer technology with advanced fossil and nuclear plants.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Waddle, D.B.; MacDonald, J.M.
1990-01-01
In an effort to analyze and document the potential for power sector efficiency improvements from generation to end-use, the Agency for International Development and the Government of Costa Rica are jointly conducting an integrated power sector efficiency analysis. Potential for energy and cost savings in power plants, transmission and distribution, and demand-side management programs are being evaluated. The product of this study will be an integrated investment plan for the Instituto Costarricense de Electricidad, incorporating both supply and demand side investment options. This paper presents the methodology employed in the study, as well as preliminary estimates of the results ofmore » the study. 14 refs., 4 figs., 5 tabs.« less
NASA Astrophysics Data System (ADS)
Xing, Shaoxu; Anakok, Isil; Zuo, Lei
2017-04-01
Accidents like Fukushima Disasters push people to improve the monitoring systems for the nuclear power plants. Thus, various types of energy harvesters are designed to power these systems and the Thermoelectric Generator (TEG) energy harvester is one of them. In order to enhance the amount of harvested power and the system efficiency, the power management stage needs to be carefully designed. In this paper, a power converter with optimized Maximum Power Point Tracking (MPPT) is proposed for the TEG Energy Harvester to power the wireless sensor network in nuclear power plant. The TEG Energy Harvester is installed on the coolant pipe of the nuclear plant and harvests energy from its heat energy while the power converter with optimized MPPT can make the TEG Energy Harvester output the maximum power, quickly response to the voltage change and provide sufficient energy for wireless sensor system to monitor the operation of the nuclear power plant. Due to the special characteristics of the Single-Ended Primary Inductor Converter (SEPIC) when it is working in the Discontinuous Inductor Current Mode (DICM) and Continuous Conduction Mode (CCM), the MPPT method presented in this paper would be able to control the converter to achieve the maximum output power in any working conditions of the TEG system with a simple circuit. The optimized MPPT algorithm will significantly reduce the cost and simplify the system as well as achieve a good performance. Experiment test results have shown that, comparing to a fixed- duty-cycle SEPIC which is specifically designed for the working on the secondary coolant loop in nuclear power plant, the optimized MPPT algorithm increased the output power by 55%.
NASA Astrophysics Data System (ADS)
Rimov, A. A.; Chukanova, T. I.; Trofimov, Yu. V.
2016-12-01
Data on the comparative analysis variants of the quality of power installations (benchmarking) applied in the power industry is systematized. It is shown that the most efficient variant of implementation of the benchmarking technique is the analysis of statistical distributions of the indicators in the composed homogenous group of the uniform power installations. The benchmarking technique aimed at revealing the available reserves on improvement of the reliability and heat efficiency indicators of the power installations of the thermal power plants is developed in the furtherance of this approach. The technique provides a possibility of reliable comparison of the quality of the power installations in their homogenous group limited by the number and adoption of the adequate decision on improving some or other technical characteristics of this power installation. The technique provides structuring of the list of the comparison indicators and internal factors affecting them represented according to the requirements of the sectoral standards and taking into account the price formation characteristics in the Russian power industry. The mentioned structuring ensures traceability of the reasons of deviation of the internal influencing factors from the specified values. The starting point for further detail analysis of the delay of the certain power installation indicators from the best practice expressed in the specific money equivalent is positioning of this power installation on distribution of the key indicator being a convolution of the comparison indicators. The distribution of the key indicator is simulated by the Monte-Carlo method after receiving the actual distributions of the comparison indicators: specific lost profit due to the short supply of electric energy and short delivery of power, specific cost of losses due to the nonoptimal expenditures for repairs, and specific cost of excess fuel equivalent consumption. The quality loss indicators are developed facilitating the analysis of the benchmarking results permitting to represent the quality loss of this power installation in the form of the difference between the actual value of the key indicator or comparison indicator and the best quartile of the existing distribution. The uncertainty of the obtained values of the quality loss indicators was evaluated by transforming the standard uncertainties of the input values into the expanded uncertainties of the output values with the confidence level of 95%. The efficiency of the technique is demonstrated in terms of benchmarking of the main thermal and mechanical equipment of the extraction power-generating units T-250 and power installations of the thermal power plants with the main steam pressure 130 atm.
NASA Technical Reports Server (NTRS)
Hals, F. A.
1981-01-01
Plants with a nominal output of 200 and 500 MWe and conforming to the same design configuration as the Task II plant were investigated. This information is intended to permit an assessment of the competitiveness of first generation MHD/steam plants with conventional steam plants over the range of 200 to 1000 MWe. The results show that net plant efficiency of the MHD plant is significantly higher than a conventional steam plant of corresponding size. The cost of electricity is also less for the MHD plant over the entire plant size range. As expected, the cost differential is higher for the larger plant and decreases with plant size. Even at the 200 MWe capacity, however, the differential in COE between the MHD plant and the conventional plant is sufficient attractive to warrant serious consideration. Escalating fuel costs will enhance the competitive position of MHD plants because they can utilize the fuel more efficiently than conventional steam plants.
Optimization of controlled processes in combined-cycle plant (new developments and researches)
NASA Astrophysics Data System (ADS)
Tverskoy, Yu S.; Muravev, I. K.
2017-11-01
All modern complex technical systems, including power units of TPP and nuclear power plants, work in the system-forming structure of multifunctional APCS. The development of the modern APCS mathematical support allows bringing the automation degree to the solution of complex optimization problems of equipment heat-mass-exchange processes in real time. The difficulty of efficient management of a binary power unit is related to the need to solve jointly at least three problems. The first problem is related to the physical issues of combined-cycle technologies. The second problem is determined by the criticality of the CCGT operation to changes in the regime and climatic factors. The third problem is related to a precise description of a vector of controlled coordinates of a complex technological object. To obtain a joint solution of this complex of interconnected problems, the methodology of generalized thermodynamic analysis, methods of the theory of automatic control and mathematical modeling are used. In the present report, results of new developments and studies are shown. These results allow improving the principles of process control and the automatic control systems structural synthesis of power units with combined-cycle plants that provide attainable technical and economic efficiency and operational reliability of equipment.
ERIC Educational Resources Information Center
US Environmental Protection Agency, 2011
2011-01-01
Saving energy through energy efficiency improvements can cost less than generating, transmitting, and distributing energy from power plants, and provides multiple economic and environmental benefits. Local governments can promote energy efficiency in their jurisdictions by developing and implementing strategies that improve the efficiency of…
NASA Technical Reports Server (NTRS)
Sovie, R. J.; Winter, J. M.; Juhasz, A. J.; Berg, R. D.
1982-01-01
A conceptual design study of the MHD/steam plant that incorporates the use of oxygen enriched air preheated in a metallic heat exchanger as the combustor oxidant showed that this plant is the most attractive for early commercial applications. The variation of performance and cost was investigated as a function of plant size. The contractors' results for the overall efficiencies are in reasonable agreement considering the slight differences in their plant designs. NASA LeRC is reviewing cost and performance results for consistency with those of previous studies, including studies of conventional steam plants. LeRC in house efforts show that there are still many tradeoffs to be considered for these oxygen enriched plants and considerable variations can be made in channel length and level of oxygen enrichment with little change in overall plant efficiency.
Diesel fuel to dc power: Navy & Marine Corps Applications
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bloomfield, D.P.
1996-12-31
During the past year Analytic Power has tested fuel cell stacks and diesel fuel processors for US Navy and Marine Corps applications. The units are 10 kW demonstration power plants. The USN power plant was built to demonstrate the feasibility of diesel fueled PEM fuel cell power plants for 250 kW and 2.5 MW shipboard power systems. We designed and tested a ten cell, 1 kW USMC substack and fuel processor. The complete 10 kW prototype power plant, which has application to both power and hydrogen generation, is now under construction. The USN and USMC fuel cell stacks have beenmore » tested on both actual and simulated reformate. Analytic Power has accumulated operating experience with autothermal reforming based fuel processors operating on sulfur bearing diesel fuel, jet fuel, propane and natural gas. We have also completed the design and fabrication of an advanced regenerative ATR for the USMC. One of the significant problems with small fuel processors is heat loss which limits its ability to operate with the high steam to carbon ratios required for coke free high efficiency operation. The new USMC unit specifically addresses these heat transfer issues. The advances in the mill programs have been incorporated into Analytic Power`s commercial units which are now under test.« less
Active Wake Redirection Control to Improve Energy Yield (Poster)
DOE Office of Scientific and Technical Information (OSTI.GOV)
Churchfield, M. J.; Fleming, P.; DeGeorge, E.
Wake effects can dramatically reduce the efficiency of waked turbines relative to the unwaked turbines. Wakes can be deflected, or 'redirected,' by applying yaw misalignment to the turbines. Yaw misalignment causes part of the rotor thrust vector to be pointed in the cross-stream direction, deflecting the flow and the wake. Yaw misalignment reduces power production, but the global increase in wind plant power due to decreased wake effect creates a net increase in power production. It is also a fairly simple control idea to implement at existing or new wind plants. We performed high-fidelity computational fluid dynamics simulations of themore » wake flow of the proposed Fishermen's Atlantic City Windfarm (FACW) that predict that under certain waking conditions, wake redirection can increase plant efficiency by 10%. This means that by applying wake redirection control, for a given watersheet area, a wind plant can either produce more power, or the same amount of power can be produced with a smaller watersheet area. With the power increase may come increased loads, though, due to the yaw misalignment. If misalignment is applied properly, or if layered with individual blade pitch control, though, the load increase can be mitigated. In this talk we will discuss the concept of wake redirection through yaw misalignment and present our CFD results of the FACW project. We will also discuss the implications of wake redirection control on annual energy production, and finally we will discuss plans to implement wake redirection control at FACW when it is operational.« less
NASA Astrophysics Data System (ADS)
Welaya, Yousri M. A.; Mosleh, M.; Ammar, Nader R.
2013-12-01
Strong restrictions on emissions from marine power plants (particularly SOx, NOx) will probably be adopted in the near future. In this paper, a combined solid oxide fuel cell (SOFC) and gas turbine fuelled by natural gas is proposed as an attractive option to limit the environmental impact of the marine sector. It includes a study of a heatrecovery system for 18 MW SOFC fuelled by natural gas, to provide the electric power demand onboard commercial vessels. Feasible heat-recovery systems are investigated, taking into account different operating conditions of the combined system. Two types of SOFC are considered, tubular and planar SOFCs, operated with either natural gas or hydrogen fuels. This paper includes a detailed thermodynamic analysis for the combined system. Mass and energy balances are performed, not only for the whole plant but also for each individual component, in order to evaluate the thermal efficiency of the combined cycle. In addition, the effect of using natural gas as a fuel on the fuel cell voltage and performance is investigated. It is found that a high overall efficiency approaching 70% may be achieved with an optimum configuration using SOFC system under pressure. The hybrid system would also reduce emissions, fuel consumption, and improve the total system efficiency.
NASA Astrophysics Data System (ADS)
Aminov, R. Z.; Kozhevnikov, A. I.
2017-10-01
In recent years in most power systems all over the world, a trend towards the growing nonuniformity of energy consumption and generation schedules has been observed. The increase in the portion of renewable energy sources is one of the important challenges for many countries. The ill-predictable character of such energy sources necessitates a search for practical solutions. Presently, the most efficient method for compensating for nonuniform generation of the electric power by the renewable energy sources—predominantly by the wind and solar energy—is generation of power at conventional fossil-fuel-fired power stations. In Russia, this problem is caused by the increasing portion in the generating capacity structure of the nuclear power stations, which are most efficient when operating under basic conditions. Introduction of hydropower and pumped storage hydroelectric power plants and other energy-storage technologies does not cover the demand for load-following power capacities. Owing to a simple design, low construction costs, and a sufficiently high economic efficiency, gas turbine plants (GTPs) prove to be the most suitable for covering the nonuniform electric-demand schedules. However, when the gas turbines are operated under varying duty conditions, the lifetime of the primary thermostressed components is considerably reduced and, consequently, the repair costs increase. A method is proposed for determination of the total operating costs considering the deterioration of the gas turbine equipment under varying duty and start-stop conditions. A methodology for optimization of the loading modes for the gas turbine equipment is developed. The consideration of the lifetime component allows varying the optimal operating conditions and, in some cases, rejecting short-time stops of the gas turbine plants. The calculations performed in a wide range of varying fuel prices and capital investments per gas turbine equipment unit show that the economic effectiveness can be increased by 5-15% by varying the operating conditions and switching to the optimal operating modes. Consequently, irrespective of the fuel price, the application of the proposed method results in selection of the most beneficial operating conditions. Consideration of the lifetime expenditure included in the optimization criterion enables enhancement of the operating efficiency.
NASA Astrophysics Data System (ADS)
Seitz, M.; Hübner, S.; Johnson, M.
2016-05-01
Direct steam generation enables the implementation of a higher steam temperature for parabolic trough concentrated solar power plants. This leads to much better cycle efficiencies and lower electricity generating costs. For a flexible and more economic operation of such a power plant, it is necessary to develop thermal energy storage systems for the extension of the production time of the power plant. In the case of steam as the heat transfer fluid, it is important to use a storage material that uses latent heat for the storage process. This leads to a minimum of exergy losses during the storage process. In the case of a concentrating solar power plant, superheated steam is needed during the discharging process. This steam cannot be superheated by the latent heat storage system. Therefore, a sensible molten salt storage system is used for this task. In contrast to the state-of-the-art thermal energy storages within the concentrating solar power area of application, a storage system for a direct steam generation plant consists of a latent and a sensible storage part. Thus far, no partial load behaviors of sensible and latent heat storage systems have been analyzed in detail. In this work, an optimized fin structure was developed in order to minimize the costs of the latent heat storage. A complete system simulation of the power plant process, including the solar field, power block and sensible and latent heat energy storage calculates the interaction between the solar field, the power block and the thermal energy storage system.
Optimizing Hydropower Day-Ahead Scheduling for the Oroville-Thermalito Project
NASA Astrophysics Data System (ADS)
Veselka, T. D.; Mahalik, M.
2012-12-01
Under an award from the U.S. Department of Energy, Office of Energy Efficiency and Renewable Energy, Water Power Program, a team of national laboratories is developing and demonstrating a suite of advanced, integrated analytical tools to assist managers and planners increase hydropower resources while enhancing the environment. As part of the project, Argonne National Laboratory is developing the Conventional Hydropower Energy and Environmental Systems (CHEERS) model to optimize day-ahead scheduling and real-time operations. We will present the application of CHEERS to the Oroville-Thermalito Project located in Northern California. CHEERS will aid California Department of Water Resources (CDWR) schedulers in making decisions about unit commitments and turbine-level operating points using a system-wide approach to increase hydropower efficiency and the value of power generation and ancillary services. The model determines schedules and operations that are constrained by physical limitations, characteristics of plant components, operational preferences, reliability, and environmental considerations. The optimization considers forebay and afterbay implications, interactions between cascaded power plants, turbine efficiency curves and rough zones, and operator preferences. CHEERS simultaneously considers over time the interactions among all CDWR power and water resources, hydropower economics, reservoir storage limitations, and a set of complex environmental constraints for the Thermalito Afterbay and Feather River habitats. Power marketers, day-ahead schedulers, and plant operators provide system configuration and detailed operational data, along with feedback on model design and performance. CHEERS is integrated with CDWR data systems to obtain historic and initial conditions of the system as the basis from which future operations are then optimized. Model results suggest alternative operational regimes that improve the value of CDWR resources to the grid while enhancing the environment and complying with water delivery obligations for non-power uses.
NASA Astrophysics Data System (ADS)
Newmark, R. L.; Cohen, S. M.; Averyt, K.; Macknick, J.; Meldrum, J.; Sullivan, P.
2014-12-01
Climate change has the potential to exacerbate reliability concerns for the power sector through changes in water availability and air temperatures. The power sector is responsible for 41% of U.S. freshwater withdrawals, primarily for power plant cooling needs, and any changes in the water available for the power sector, given increasing competition among water users, could affect decisions about new power plant builds and reliable operations for existing generators. Similarly, increases in air temperatures can reduce power plant efficiencies, which in turn increases fuel consumption as well as water withdrawal and consumption rates. This analysis describes an initial link between climate, water, and electricity systems using the National Renewable Energy Laboratory's (NREL) Regional Energy Deployment System (ReEDS) electricity system capacity expansion model. Average surface water runoff projections from Coupled Model Intercomparison Project 5 (CMIP5) data are applied to surface water available to generating capacity in ReEDS, and electric sector growth is compared with and without climate-influenced water availability for the 134 electricity balancing regions in the ReEDS model. In addition, air temperature changes are considered for their impacts on electricity load, transmission capacity, and power plant efficiencies and water use rates. Mean climate projections have only a small impact on national or regional capacity growth and water use because most regions have sufficient unappropriated or previously retired water access to offset climate impacts. Climate impacts are notable in southwestern states, which experience reduced water access purchases and a greater share of water acquired from wastewater and other higher-cost water resources. The electric sector climate impacts demonstrated herein establish a methodology to be later exercised with more extreme climate scenarios and a more rigorous representation of legal and physical water availability.
Study on emission of hazardous trace elements in a 350 MW coal-fired power plant. Part 1. Mercury.
Zhao, Shilin; Duan, Yufeng; Chen, Lei; Li, Yaning; Yao, Ting; Liu, Shuai; Liu, Meng; Lu, Jianhong
2017-10-01
Hazardous trace elements (HTEs), especially mercury, emitted from coal-fired power plants had caused widespread concern worldwide. Field test on mercury emissions at three different loads (100%, 85%, 68% output) using different types of coal was conducted in a 350 MW pulverized coal combustion power plant equipped with selective catalytic reduction (SCR), electrostatic precipitator and fabric filter (ESP + FF), and wet flue gas desulfurization (WFGD). The Ontario Hydro Method was used for simultaneous flue gas mercury sampling for mercury at the inlet and outlet of each of the air pollutant control device (APCD). Results showed that mercury mass balance rates of the system or each APCD were in the range of 70%-130%. Mercury was mainly distributed in the flue gas, followed by ESP + FF ash, WFGD wastewater, and slag. Oxidized mercury (Hg 2+ ) was the main form of mercury form in the flue gas emitted to the atmosphere, which accounted for 57.64%-61.87% of total mercury. SCR was favorable for elemental mercury (Hg 0 ) removal, with oxidation efficiency of 50.13%-67.68%. ESP + FF had high particle-bound mercury (Hg p ) capture efficiency, at 99.95%-99.97%. Overall removal efficiency of mercury by the existing APCDs was 58.78%-73.32%. Addition of halogens or oxidants for Hg 0 conversion, and inhibitors for Hg 0 re-emission, plus the installation of a wet electrostatic precipitator (WESP) was a good way to improve the overall removal efficiency of mercury in the power plants. Mercury emission factor determined in this study was from 0.92 to 1.17 g/10 12 J. Mercury concentration in the emitted flue gas was much less than the regulatory limit of 30 μg/m 3 . Contamination of mercury in desulfurization wastewater should be given enough focus. Copyright © 2017. Published by Elsevier Ltd.
NASA Astrophysics Data System (ADS)
Sinaga, R. H. M.; Manik, Y.
2018-03-01
Sibayak Geothermal Power Plant (SGPP) is one of the plants being developed by Pertamina Geothermal Energy (PGE) at the upstream phase. At the downstream phase, State - owned Electricity Company (PLN) through PT. Dizamatra Powerindo is the developer. The gross capacity of the power plant is 13.3 MW, consisting 1 unit of Monoblock (2 MW) developed by PGE and 2 units (2×5.65 MW) operated through Energy Sales Contract by PLN. During the development phase of a geothermal power plant, there is a chance to reduce the utility power in order to increase the overall plant efficiency. Reducing the utility power can be attempted by utilizing the wet bulb temperature fluctuation. In this study, a modeling process is developed by using Engineering Equation Solver (EES) software version 9.430. The possibility of energy saving is indicated by condenser pressure changes as a result of wet bulb temperature fluctuation. The result of this study indicates that the change of condenser pressure is about 50.8% on the constant liquid/gas (L/G) condition of the wet bulb temperature of 15°C to 25°C. Further result indicates that in this power plant, Cooling Tower Fan (CTF) is the facility that has the greatest utility load, followed by Hot Well Pump (HWP). The saving of the greatest utility load is applied trough Variable Frequency Drive (VFD) instrumentation. The result of this modeling has been validated by actual operations data (log sheet). The developed model has also been reviewed trough Specific Steam Consumption (SSC), resulting that constant L/G condition allows the optimum condition on of the wet bulb temperature of 15°C to 25°C.
NASA Technical Reports Server (NTRS)
Maag, W. L.; Bollenbacher, G.
1974-01-01
Energy and economic analyses were performed for an on-site power-plant with waste heat recovery. The results show that for any specific application there is a characteristic power conversion efficiency that minimizes fuel consumption, and that efficiencies greater than this do not significantly improve fuel consumption. This type of powerplant appears to be a reasonably attractive investment if higher fuel costs continue.
Fuel Cell Power Plants Renewable and Waste Fuels
2011-01-13
of FuelCell Energy, Inc. Fuels Resources for DFC • Natural Gas and LNG • Propane • Biogas (by Anaerobicnaerobic Digestion) - Municipal Waste...FUEL RESOURCES z NATURAL GAS z PROPANE z DFC H2 (50-60%) z ETHANOL zWASTE METHANE z BIOGAS z COAL GAS Diversity of Fuels plus High Efficiency...trademarks (®) of FuelCell Energy, Inc. DFC Advantages for Biogas • More power for given amount of biogas : Higher efficiency than
Wireless microwave acoustic sensor system for condition monitoring in power plant environments
DOE Office of Scientific and Technical Information (OSTI.GOV)
Pereira da Cunha, Mauricio
This project successfully demonstrated novel wireless microwave acoustic temperature and pressure sensors that can be embedded into equipment and structures located in fossil fuel power plant environments to monitor the condition of components such as steam headers, re-heat lines, water walls, burner tubes, and power turbines. The wireless microwave acoustic sensor technology researched and developed through a collaborative partnership between the University of Maine and Environetix Technologies Corporation can provide a revolutionary impact in the power industry since it is anticipated that the wireless sensors will deliver reliable real-time sensing information in harsh power plant conditions that involve temperatures upmore » to 1100oC and pressures up to 750 psi. The work involved the research and development of novel high temperature harsh environment thin film electrodes, piezoelectric smart microwave acoustic sensing elements, sensor encapsulation materials that were engineered to function over long times up to 1100oC, and a radio-frequency (RF) wireless interrogation electronics unit that are located both inside and outside the high temperature harsh environment. The UMaine / Environetix team have interacted with diverse power plant facilities, and identified as a testbed a local power generation facility, which burns municipal solid waste (MSW), the Penobscot Energy Recovery Company (PERC), Orrington, Maine. In this facility Environetix / UMaine successfully implemented and tested multiple wireless temperature sensor systems within the harsh-environment of the economizer chamber and at the boiler tubes, transferring the developed technology to the power plant environment to perform real-time sensor monitoring experiments under typical operating conditions, as initially targeted in the project. The wireless microwave acoustic sensor technology developed under this project for power plant applications offers several significant advantages including wireless, battery-free, maintenance-free operation, and operation in the harsh-environment of power plant equipment up to about 1100 oC. Their small size and configuration allows flexible sensor placement and embedding of multiple sensor arrays into a variety of components within power systems that can be interrogated by a single RF unit. The outcomes of this project and technological transfer respond to a DOE analysis need, which indicated that if one percent efficiency in coal burning is achieved, an additional 2 gigawatt-hours of energy per year is generated and the resulting coal cost savings is $300 million per year, also accompanied by a reduction of more than 10 million metric tons of CO2 per year emitted into the atmosphere. Therefore, the developed harsh environment wireless microwave acoustic sensor technology and the technological transfer achievements that resulted from the execution of this project have significant impact for power plant equipment and systems and are well-positioned to contribute to the cost reduction in power generation, the increase in power plant efficiency, the improvement in maintenance, the reduction in down-time, and the decrease in environmental pollution. The technology is also in a position to be extended to address other types of high-temperature harsh-environment power plant and energy sector sensing needs.« less
Understanding refractory failures
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bases, G.J.
2006-01-15
Compared to most pieces of a power plant, refractory costs very little to install. Yet, if improperly manufactured, specified, stored, mixed installed, cured, or dried, refractory may cause problems that can significantly decrease a plant's operating efficiency and flexibility. Like Rodney Dangerfield, refractory design and installation deserve more respect. 4 photos.
Accurate measurement of transgene copy number in crop plants using droplet digital PCR
USDA-ARS?s Scientific Manuscript database
Technical abstract: Genetic transformation is a powerful means for the improvement of crop plants, but requires labor and resource intensive methods. An efficient method for identifying single copy transgene insertion events from a population of independent transgenic lines is desirable. Currently ...
Accurate measure of transgene copy number in crop plants using droplet digital PCR
USDA-ARS?s Scientific Manuscript database
Genetic transformation is a powerful means for the improvement of crop plants, but requires labor- and resource-intensive methods. An efficient method for identifying single-copy transgene insertion events from a population of independent transgenic lines is desirable. Currently, transgene copy numb...
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ali, Syed Firasat; Hajek, Brian K.; Usman, Shoaib
The report emphasizes smooth transition from paper-based procedure systems (PBPSs) to computer-based procedure systems (CBPSs) for the existing commercial nuclear power plants in the U.S. The expected advantages and of the transition are mentioned including continued, safe and efficient operation of the plants under their recently acquired or desired extended licenses. The report proposes a three-stage survey to aid in developing a national strategic plan for the transition from PBPSs to CBPSs. It also includes a comprehensive questionnaire that can be readily used for the first stage of the suggested survey.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kuehn, S.E.
1995-03-01
This article examines why the diesel engine is a very attractive choice for producing power in the combined-cycle configuration. The medium-speed diesel is already one of the most efficient simple cycle sources of electricity, especially with lower grade fuels. Large units have heat-rate efficiencies as high as 45%, equating to a heat rate of 7,580 Btu/k Whr, and no other power production prime mover can match this efficiency. Diesels also offer designers fuel flexibility and can burn an extreme variety of fuels without sacrificing many of its positive operating attributes. Diesels are the first building block in a highly efficientmore » combined cycle system that relies on the hot gas and oxygen in the diesel`s exhaust to combust either natural gas, light distillate oil, heavy oil or coal, in a boiler. By using a fired boiler, steam can be generated at sufficient temperature and pressure to operate a Rankine steam cycle efficiently. Diesel combined-cycle plants can be configured in much the same way a gas turbine plant would be. However, the diesel combined-cycle scheme requires supplemental firing to generate appropriate steam conditions. The most efficient cycle, therefore, would not be achieved until combustion air and supplemental fuel are minimized to levels that satisfy steam conditions, steam generation and power generation constraints.« less
Ion collector design for an energy recovery test proposal with the negative ion source NIO1
DOE Office of Scientific and Technical Information (OSTI.GOV)
Variale, V., E-mail: vincenzo.variale@ba.infn.it; Cavenago, M.; Agostinetti, P.
2016-02-15
Commercial viability of thermonuclear fusion power plants depends also on minimizing the recirculation power used to operate the reactor. The neutral beam injector (NBI) remains one of the most important method for plasma heating and control. For the future fusion power plant project DEMO, a NBI wall plug efficiency at least of 0.45 is required, while efficiency of present NBI project is about 0.25. The D{sup −} beam from a negative ion source is partially neutralized by a gas cell, which leaves more than 40% of energy in residual beams (D{sup −} and D{sup +}), so that an ion beammore » energy recovery system can significantly contribute to optimize efficiency. Recently, the test negative ion source NIO1 (60 keV, 9 beamlets with 15 mA H{sup −} each) has been designed and built at RFX (Padua) for negative ion production efficiency and the beam quality optimization. In this paper, a study proposal to use the NIO1 source also for a beam energy recovery test experiment is presented and a preliminary design of a negative ion beam collector with simulations of beam energy recovery is discussed.« less
Life cycle assessment of sewage sludge co-incineration in a coal-based power station.
Hong, Jingmin; Xu, Changqing; Hong, Jinglan; Tan, Xianfeng; Chen, Wei
2013-09-01
A life cycle assessment was conducted to evaluate the environmental and economic effects of sewage sludge co-incineration in a coal-fired power plant. The general approach employed by a coal-fired power plant was also assessed as control. Sewage sludge co-incineration technology causes greater environmental burden than does coal-based energy production technology because of the additional electricity consumption and wastewater treatment required for the pretreatment of sewage sludge, direct emissions from sludge incineration, and incinerated ash disposal processes. However, sewage sludge co-incineration presents higher economic benefits because of electricity subsidies and the income generating potential of sludge. Environmental assessment results indicate that sewage sludge co-incineration is unsuitable for mitigating the increasing pressure brought on by sewage sludge pollution. Reducing the overall environmental effect of sludge co-incineration power stations necessitates increasing net coal consumption efficiency, incinerated ash reuse rate, dedust system efficiency, and sludge water content rate. Copyright © 2013 Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Brzęczek, Mateusz; Bartela, Łukasz
2013-12-01
This paper presents the parameters of the reference oxy combustion block operating with supercritical steam parameters, equipped with an air separation unit and a carbon dioxide capture and compression installation. The possibility to recover the heat in the analyzed power plant is discussed. The decision variables and the thermodynamic functions for the optimization algorithm were identified. The principles of operation of genetic algorithm and methodology of conducted calculations are presented. The sensitivity analysis was performed for the best solutions to determine the effects of the selected variables on the power and efficiency of the unit. Optimization of the heat recovery from the air separation unit, flue gas condition and CO2 capture and compression installation using genetic algorithm was designed to replace the low-pressure section of the regenerative water heaters of steam cycle in analyzed unit. The result was to increase the power and efficiency of the entire power plant.
Diesel Fueled SOFC for Class 7/Class 8 On-Highway Truck Auxiliary Power
DOE Office of Scientific and Technical Information (OSTI.GOV)
Vesely, Charles John-Paul; Fuchs, Benjamin S.; Booten, Chuck W.
2010-03-31
The following report documents the progress of the Cummins Power Generation (CPG) Diesel Fueled SOFC for Class 7/Class 8 On-Highway Truck Auxiliary Power (SOFC APU) development and final testing under the U.S. Department of Energy (DOE) Energy Efficiency and Renewable Energy (EERE) contract DE-FC36-04GO14318. This report overviews and summarizes CPG and partner development leading to successful demonstration of the SOFC APU objectives and significant progress towards SOFC commercialization. Significant SOFC APU Milestones: Demonstrated: Operation meeting SOFC APU requirements on commercial Ultra Low Sulfur Diesel (ULSD) fuel. SOFC systems operating on dry CPOX reformate. Successful start-up and shut-down of SOFC APUmore » system without inert gas purge. Developed: Low cost balance of plant concepts and compatible systems designs. Identified low cost, high volume components for balance of plant systems. Demonstrated efficient SOFC output power conditioning. Demonstrated SOFC control strategies and tuning methods.« less
Bracale, Antonio; Barros, Julio; Cacciapuoti, Angela Sara; ...
2015-06-10
Electrical power systems are undergoing a radical change in structure, components, and operational paradigms, and are progressively approaching the new concept of smart grids (SGs). Future power distribution systems will be characterized by the simultaneous presence of various distributed resources, such as renewable energy systems (i.e., photovoltaic power plant and wind farms), storage systems, and controllable/non-controllable loads. Control and optimization architectures will enable network-wide coordination of these grid components in order to improve system efficiency and reliability and to limit greenhouse gas emissions. In this context, the energy flows will be bidirectional from large power plants to end users andmore » vice versa; producers and consumers will continuously interact at different voltage levels to determine in advance the requests of loads and to adapt the production and demand for electricity flexibly and efficiently also taking into account the presence of storage systems.« less
Solar perspectives - Israel, solar pond innovator
NASA Astrophysics Data System (ADS)
Winsberg, S.
1981-07-01
Existing and planned solar pond electricity producing power plants in Israel and California are discussed. Salt ponds, with salinity increasing with depth, are coupled with low temperature, organic working fluid Rankine cycle engines to form self-storage, nonpolluting, electric plants. Average pond thermal gradients range from 25 C surface to 90 C at the bottom; 160 GW of potential power have been projected as currently available from existing natural solar ponds from a partial survey of 14 countries. The largest installation to date has a 220 kW output, and a 5 MW plant is scheduled for completion in 1983. Efficiencies of 10% and a cost of $2,000/kW for a 40 MW plant are projected, a cost which is comparable to that of conventional plants. The 40 MW plant is an optimized design, allowing for modular plant additions to increase capacity.
Xu, Changqing; Hong, Jinglan; Ren, Yixin; Wang, Qingsong; Yuan, Xueliang
2015-08-01
This study aims at qualifying air pollutants and environmental impacts generated from coal-based power plants and providing useful information for decision makers on the management of coal-based power plants in China. Results showed that approximately 9.03, 54.95, 62.08, and 12.12% of the national carbon dioxide, sulfur dioxide, nitrogen oxides, and particulate matter emissions, respectively, in 2011were generated from coal-based electricity generation. The air pollutants were mainly generated from east China because of the well-developed economy and energy-intensive industries in the region. Coal-washing technology can simply and significantly reduce the environmental burden because of the relativity low content of coal gangue and sulfur in washed coal. Optimizing the efficiency of raw materials and energy consumption is additional key factor to reduce the potential environmental impacts. In addition, improving the efficiency of air pollutants (e.g., dust, mercury, sulfur dioxide, nitrogen oxides) control system and implementing the strict requirements on air pollutants for power plants are important ways for reducing the potential environmental impacts of coal-based electricity generation in China.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mukherjee, S., E-mail: sankha.deepp@gmail.com; Mondal, P., E-mail: mondal.pradip87@gmail.com; Ghosh, S., E-mail: sudipghosh.becollege@gmail.com
Rapid depletion of fossil fuel has forced mankind to look into alternative fuel resources. In this context, biomass based power generation employing gas turbine appears to be a popular choice. Bio-gasification based combined cycle provides a feasible solution as far as grid-independent power generation is concerned for rural electrification projects. Indirectly heated gas turbine cycles are promising alternatives as they avoid downstream gas cleaning systems. Advanced thermodynamic cycles have become an interesting area of study to improve plant efficiency. Water injected system is one of the most attractive options in this field of applications. This paper presents a theoretical modelmore » of a biomass gasification based combined cycle that employs an indirectly heated humid air turbine (HAT) in the topping cycle. Maximum overall electrical efficiency is found to be around 41%. Gas turbine specific air consumption by mass is minimum when pressure ratio is 6. The study reveals that, incorporation of the humidification process helps to improve the overall performance of the plant.« less
Vakalis, Stergios; Moustakas, Konstantinos; Loizidou, Maria
2018-06-01
Waste-to-energy plants have the peculiarity of being considered both as energy production and as waste destruction facilities and this distinction is important for legislative reasons. The efficiency of waste-to-energy plants must be objective and consistent, independently if the focus is the production of energy, the destruction of waste or the recovery/upgrade of materials. With the introduction of polygeneration technologies, like gasification, the production of energy and the recovery/upgrade of materials, are interconnected. The existing methodology for assessing the efficiency of waste-to-energy plants is the R1 formula, which does not take into consideration the full spectrum of the operations that take place in waste-to-energy plants. This study introduces a novel methodology for assessing the efficiency of waste-to-energy plants and is defined as the 3T method, which stands for 'trapezoidal thermodynamic technique'. The 3T method is an integrated approach for assessing the efficiency of waste-to-energy plants, which takes into consideration not only the production of energy but also the quality of the products. The value that is returned from the 3T method can be placed in a tertiary diagram and the global efficiency map of waste-to-energy plants can be produced. The application of the 3T method showed that the waste-to-energy plants with high combined heat and power efficiency and high recovery of materials are favoured and these outcomes are in accordance with the cascade principle and with the high cogeneration standards that are set by the EU Energy Efficiency Directive.
NASA Technical Reports Server (NTRS)
Hertzberg, A.; Decher, R.; Mattick, A. T.; Lau, C. V.
1978-01-01
High temperature heat engines designed to make maximum use of the thermodynamic potential of concentrated solar radiation are described. Plasmas between 2000 K and 4000 K can be achieved by volumetric absorption of radiation in alkali metal vapors, leading to thermal efficiencies up to 75% for terrestrial solar power plants and up to 50% for space power plants. Two machines capable of expanding hot plasmas using practical technology are discussed. A binary Rankine cycle uses fluid mechanical energy transfer in a device known as the 'Comprex' or 'energy exchanger.' The second machine utilizes magnetohydrodynamics in a Brayton cycle for space applications. Absorption of solar energy and plasma radiation losses are investigated for a solar superheater using potassium vapor.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bland, Alan E.; Sellakumar, Kumar Muthusami; Newcomer, Jesse D.
Efficient coal pre-processing systems (69) integrated with gasification, oxy-combustion, and power plant systems include a drying chamber (28), a volatile metal removal chamber (30), recirculated gases, including recycled carbon dioxide (21), nitrogen (6), and gaseous exhaust (60) for increasing the efficiencies and lowering emissions in various coal processing systems.
NASA Astrophysics Data System (ADS)
Miara, A.; Macknick, J.; Vorosmarty, C. J.; Cohen, S. M.; Rosenzweig, B.
2014-12-01
The Northeastern United States (NE) relies heavily on thermoelectric power plants (90% of total capacity) to provide electricity to more than 70 million people. This region's power plants require consistent, large volumes of water at sufficiently cold temperatures to generate electricity efficiently, and withdraw approximately 10.5 trillion gallons of water annually. Previous findings indicate that assessments of future electricity pathways must account for water availability, water temperature and the changing climate, as changes in these conditions may limit operational efficiency in the future. To account for such electric system vulnerabilities, we have created a link between an electricity system capacity expansion model (ReEDS) and a hydrologic model that is coupled to a power plant simulation model (FrAMES-TP2M) that allows for a new approach to analyze electricity system development, performance, and environmental impacts. Together, these coupled tools allow us to estimate electricity development and operations in the context of a changing climate and impacts on the seasonal spatial and temporal variability of water resources, downstream thermal effluents that cause plant-to-plant interferences and harm aquatic habitat, economic costs of water conservation methods and associated carbon emissions. In this study, we test and compare a business-as-usual strategy with three alternative water management scenarios that include changes in cooling technologies and water sources utilized for the years 2014-2050. Results of these experiments can provide useful insight into the feasibility of the electricity expansion scenarios in terms of associated water use and thermal impacts, carbon emissions, the cost of generating electricity, and also highlight the importance of accounting for water resources in future power sector planning and performance assessments.
Analysis of a fuel cell on-site integrated energy system for a residential complex
NASA Technical Reports Server (NTRS)
Simons, S. N.; Maag, W. L.
1979-01-01
Declining supplies of domestic oil and gas and the increased cost of energy resulted in a renewed emphasis in utilizing available resources in the most efficient manner possible. This, in turn, brought about a reassessment of a number of methods for converting fossil fuels to end uses at the highest practical efficiency. One of these is the on-site integrated energy system (OS/IES). This system provides electric power from an on-site power plant and recovers heat from the power plant that would normally be rejected to the environment. An OS/IES is potentially useful in any application that requires both electricity and heat. Several OS/IES are analyzed for a residential complex. The paper is divided into two sections; the first compares three energy supply systems, the second compares various designs for fuel cell OS/IES.
Beyond ITER: neutral beams for a demonstration fusion reactor (DEMO) (invited).
McAdams, R
2014-02-01
In the development of magnetically confined fusion as an economically sustainable power source, International Tokamak Experimental Reactor (ITER) is currently under construction. Beyond ITER is the demonstration fusion reactor (DEMO) programme in which the physics and engineering aspects of a future fusion power plant will be demonstrated. DEMO will produce net electrical power. The DEMO programme will be outlined and the role of neutral beams for heating and current drive will be described. In particular, the importance of the efficiency of neutral beam systems in terms of injected neutral beam power compared to wallplug power will be discussed. Options for improving this efficiency including advanced neutralisers and energy recovery are discussed.
Efficient, full-spectrum, long-lived, non-toxic microwave lamp for plant growth
NASA Technical Reports Server (NTRS)
Maclennan, Donald A.; Turner, Brian P.; Dolan, James T.; Ury, Michael G.; Gustafson, Paul
1994-01-01
Fusion Systems Corporation has developed a mercury-free, low infrared, efficient microwave lamp using a benign sulfur based fill optimized for visible light. Our literature search and discussions with researchers directed us to enhance the bulbs red output. We have demonstrated a photosynthetic efficacy of over 2 micro-moles per microwave joule which corresponds to over 1.3 micro-moles per joule at the power main. Recent work has shown we can make additional increases in overall system efficiency. During the next two years, we expect to demonstrate a system capable of producing more than 1.5 micro-moles/joule measured at the power main with significantly less IR than alternative lamp systems. We determined optimal plant growth light requirements via a literature search and researcher input. We surveyed candidate lamp fill materials to be used in combination with sulfur and explored several methods of increasing photosynthetic efficacy.
Techno-economic analysis of supercritical carbon dioxide power blocks
NASA Astrophysics Data System (ADS)
Meybodi, Mehdi Aghaei; Beath, Andrew; Gwynn-Jones, Stephen; Veeraragavan, Anand; Gurgenci, Hal; Hooman, Kamel
2017-06-01
Developing highly efficient power blocks holds the key to enhancing the cost competitiveness of Concentration Solar Thermal (CST) technologies. Supercritical CO2 (sCO2) Brayton cycles have proved promising in providing equivalent or higher cycle efficiency than supercritical or superheated steam cycles at temperatures and scales relevant for Australian CST applications. In this study, a techno-economic methodology is developed using a stochastic approach to determine the ranges for the cost and performance of different components of central receiver power plants utilizing sCO2 power blocks that are necessary to meet the Australian Solar Thermal Initiative (ASTRI) final LCOE target of 12 c/kWh.
Space solar power - An energy alternative
NASA Technical Reports Server (NTRS)
Johnson, R. W.
1978-01-01
The space solar power concept is concerned with the use of a Space Power Satellite (SPS) which orbits the earth at geostationary altitude. Two large symmetrical solar collectors convert solar energy directly to electricity using photovoltaic cells woven into blankets. The dc electricity is directed to microwave generators incorporated in a transmitting antenna located between the solar collectors. The antenna directs the microwave beam to a receiving antenna on earth where the microwave energy is efficiently converted back to dc electricity. The SPS design promises 30-year and beyond lifetimes. The SPS is relatively pollution free as it promises earth-equivalence of 80-85% efficient ground-based thermal power plant.
NASA Astrophysics Data System (ADS)
Khroustalev, V. A.; Simonyan, A. A.
2017-11-01
There was carried out an analysis of technical characteristics of boiler houses in a number of Russian NPPs. We justified the possibility of their usage for autonomous generation of electrical energy and improvement of maneuvering properties of power complexes as a single object of regulation, as well as the possibility of increasing the total generation capacity of NPP power units during peak hours. Then the selection of the main equipment of house boiler for its autonomous work was done. There were composed basic thermal diagrams of the power complex on the basis of NPP start-up boiler (SUB) and the satellite turbine. The article also considers some options of reconstruction of SUB into the heat-recovery boiler. The developed power complexes are designed to be used on the basis of the two-loop NPP with pressurized power reactors (PWR). They can be applied with serial and projected domestic NPP units with the aim of getting more power, improving the plant capacity factor (PCF), as well as with the aim of NPP participation in the regulation of the load curve above the nominal value with partial replacement of new construction. The power complexes can be a relevant solution in the light of the energy strategy of the Russian Federation, which is aimed at, firstly, further improvement of efficiency and safety at the NPP, and, secondly, solving the problem of adequate maneuverability and ensuring the adjustment range limits in power systems with high share of nuclear power plants. Implementation of new hybrid thermal diagrams allows simultaneous increase in the safety of NPP, and usage of nuclear power plants emergency frequency control in power systems by fast load drop and rise by -4÷+2 % of the nominal value. Due to the usage of different fuels in power complexes, uranium loading in the core of reactor facilities and gas in SUB, there was proposed and formalized the criterion of “thermoeconomic index”. This criterion represents the ratio of the gross receipt from the sale of electricity to the total cost of fuel of all kinds, spent on ensuring power efficiency.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Phadke, Amol; Abhyankar, Nikit; Shah, Nihar
Electricity demand for room ACs is growing very rapidly in emerging economies such as India. We estimate the electricity demand from room ACs in 2030 in India considering factors such as weather and income growth using market data on penetration of ACs in different income classes and climatic regions. We discuss the status of the current standards, labels, and incentive programs to improve the efficiency of room ACs in these markets and assess the potential for further large improvements in efficiency and find that efficiency can be improved by over 40percent cost effectively. The total potential energy savings from Roommore » AC efficiency improvement in India using the best available technology will reach over 118 TWh in 2030; potential peak demand saving is found to be 60 GW by 2030. This is equivalent to avoiding 120 new coal fired power plants of 500 MW each. We discuss policy options to complement, expand and improve the ongoing programs to capture this large potential.« less
NASA Technical Reports Server (NTRS)
Schum, Harold J.; Whitney, Warren J.
1949-01-01
A single-stage modification of the turbine from a Mark 25 torpedo power plant was investigated to determine the performance with two nozzle designs in combination with special rotor blades having a 20 inlet angle. The performance is presented in terms of blade, rotor, and brake efficiency as a function of blade-jet speed ratio for pressure ratios of 8, 15 (design), and 20. The blade efficiency with the nozzle having circular pas- sages (K) was equal to or higher than that with the nozzle having rectangular passages (J) for all pressure ratios and speeds investigated. The maximum blade efficiency of 0.571 was obtained with nozzle K at a pressure ratio of 8 and a blade-jet speed ratio of 0.296. The difference in blade efficiency was negligible at a pressure ratio of 8 at the low speeds; the maxim difference was 0.040 at a pressure ratio of 20 and a blade-jet speed ratio of 0.260.
NASA Astrophysics Data System (ADS)
Moshkbar-Bakhshayesh, Khalil; Ghofrani, Mohammad B.
2014-02-01
This study aims to improve the performance of nuclear power plants (NPPs) transients training and identification using the latest advances of error back-propagation (EBP) learning algorithm. To this end, elements of EBP, including input data, initial weights, learning rate, cost function, activation function, and weights updating procedure are investigated and an efficient neural network is developed. Usefulness of modular networks is also examined and appropriate identifiers, one for each transient, are employed. Furthermore, the effect of transient type on transient identifier performance is illustrated. Subsequently, the developed transient identifier is applied to Bushehr nuclear power plant (BNPP). Seven types of the plant events are probed to analyze the ability of the proposed identifier. The results reveal that identification occurs very early with only five plant variables, whilst in the previous studies a larger number of variables (typically 15 to 20) were required. Modular networks facilitated identification due to its sole dependency on the sign of each network output signal. Fast training of input patterns, extendibility for identification of more transients and reduction of false identification are other advantageous of the proposed identifier. Finally, the balance between the correct answer to the trained transients (memorization) and reasonable response to the test transients (generalization) is improved, meeting one of the primary design criteria of identifiers.
Magnetic power conversion with machines containing full or porous wheel heat exchangers
NASA Astrophysics Data System (ADS)
Egolf, Peter W.; Kitanovski, Andrej; Diebold, Marc; Gonin, Cyrill; Vuarnoz, Didier
2009-04-01
A first part of the article contains a thermodynamic theory describing the temperature distribution in a Curie wheel. The occurring nonlinear ordinary differential equation has an analytical solution. If a Curie wheel is stabilized by levitation, it is named Palmy wheel. These wheels show a full structure, and because of this reason, their uptake of heat from a flame (Curie wheel) or by (solar) light absorption (Palmy wheel) only on the periphery of a cylinder is very limited. To improve the method, a modification of the principle by introducing a convective heat transport into a porous wheel is discussed. By this the power conversion rate from a heat flux to mechanical and electric power is very much increased. The second part of the article presents results of a theoretical/numerical study on the efficiencies of magnetic power conversion plants operating with porous wheels. Furthermore, these efficiencies—which are promising—are compared with those of existing power conversion plants, as e.g. geothermal binary cycle power plants.
Carbonate fuel cells: Milliwatts to megawatts
NASA Astrophysics Data System (ADS)
Farooque, M.; Maru, H. C.
The carbonate fuel cell power plant is an emerging high efficiency, ultra-clean power generator utilizing a variety of gaseous, liquid, and solid carbonaceous fuels for commercial and industrial applications. The primary mover of this generator is a carbonate fuel cell. The fuel cell uses alkali metal carbonate mixtures as electrolyte and operates at ∼650 °C. Corrosion of the cell hardware and stability of the ceramic components have been important design considerations in the early stages of development. The material and electrolyte choices are founded on extensive fundamental research carried out around the world in the 60s and early 70s. The cell components were developed in the late 1970s and early 1980s. The present day carbonate fuel cell construction employs commonly available stainless steels. The electrodes are based on nickel and well-established manufacturing processes. Manufacturing process development, scale-up, stack tests, and pilot system tests dominated throughout the 1990s. Commercial product development efforts began in late 1990s leading to prototype field tests beginning in the current decade leading to commercial customer applications. Cost reduction has been an integral part of the product effort. Cost-competitive product designs have evolved as a result. Approximately half a dozen teams around the world are pursuing carbonate fuel cell product development. The power plant development efforts to date have mainly focused on several hundred kW (submegawatt) to megawatt-class plants. Almost 40 submegawatt units have been operating at customer sites in the US, Europe, and Asia. Several of these units are operating on renewable bio-fuels. A 1 MW unit is operating on the digester gas from a municipal wastewater treatment plant in Seattle, Washington (US). Presently, there are a total of approximately 10 MW capacity carbonate fuel cell power plants installed around the world. Carbonate fuel cell products are also being developed to operate on coal-derived gases, diesel, and other logistic fuels. Innovative carbonate fuel cell/turbine hybrid power plant designs promising record energy conversion efficiencies approaching 75% have also emerged. This paper will review the historical development of this unique technology from milliwatt-scale laboratory cells to present megawatt-scale commercial power plants.
Fuel cell programs in the United States for stationary power applications
DOE Office of Scientific and Technical Information (OSTI.GOV)
Singer, M.
1996-04-01
The Department of Energy (DOE), Office of Fossil Energy, is participating with the private sector in sponsoring the development of molten carbonate fuel cell (MCFC) and solid oxide fuel cell (SOFC) technologies for application in the utility, commercial and industrial sectors. Phosphoric acid fuel cell (PAFC) development was sponsored by the Office of Fossil Energy in previous years and is now being commercialized by the private sector. Private sector participants with the Department of Energy include the Electric Power Research Institute (EPRI), the Gas Research institute (GRI), electric and gas utilities, universities, manufacturing companies and their suppliers. through continued governmentmore » and private sector support, fuel cell systems are emerging power generation technologies which are expected to have significant worldwide impacts. An industry with annual sales of over a billion dollars is envisioned early in the 21st century. PAFC power plants have begun to enter the marketplace and MCFC and SOFC power plants are expected to be ready to enter the marketplace in the late 1990s. In support of the efficient and effective use of our natural resources, the fuel cell program seeks to increase energy efficiency and economic effectiveness of power generation. This is to be accomplished through effectiveness of power generation. This is accomplished through the development and commercialization of cost-effective, efficient and environmentally desirable fuel cell systems which will operate on fossil fuels in multiple and end use sectors.« less
NASA Technical Reports Server (NTRS)
1984-01-01
Chesebrough-Pond's operates 32 plants across the nation and in those plants are more than 10,000 electric motors. In an effort to cut down on waste of electrical power used by these motors, Chesebrough organized a Corporate Advanced Technology Group to devise ways of improving productivity and cut manufacturing costs. Chesebrough used NASA's Marshall Space Flight Center's Power Factor Controller technology as a departure point for development of their own computerized motor controller that enables motors to operate at maximum efficiency regardless of the motor's applications or operating condition.
5. 7 MW Tornados for Dunn Paper mill power CHP plant
DOE Office of Scientific and Technical Information (OSTI.GOV)
Jeffs, E.
The first commercial installation in the United States of Ruston's high efficiency Tornado gas turbine is now fully operational at the Dunn Paper Company's Port Huron, Michigan paper mill where they make special light weight papers for packaging and business forms. It's a cogeneration installation powered by three Tornados and two waste heat recovery boilers which provide the mill with all of its electricity and process steam requirements - at high overall thermal efficiency.
Economics of internal and external energy storage in solar power plant operation
NASA Technical Reports Server (NTRS)
Manvi, R.; Fujita, T.
1977-01-01
A simple approach is formulated to investigate the effect of energy storage on the bus-bar electrical energy cost of solar thermal power plants. Economic analysis based on this approach does not require detailed definition of a specific storage system. A wide spectrum of storage system candidates ranging from hot water to superconducting magnets can be studied based on total investment and a rough knowledge of energy in and out efficiencies. Preliminary analysis indicates that internal energy storage (thermal) schemes offer better opportunities for energy cost reduction than external energy storage (nonthermal) schemes for solar applications. Based on data and assumptions used in JPL evaluation studies, differential energy costs due to storage are presented for a 100 MWe solar power plant by varying the energy capacity. The simple approach presented in this paper provides useful insight regarding the operation of energy storage in solar power plant applications, while also indicating a range of design parameters where storage can be cost effective.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Fraas, A.P.
1971-08-01
The facts of fuel supply limitations, environmental quality demands, and spiraling electric generating costs strongly favor development of electric power plants that simultaneously run at higher efficiency, i.e., higher temperature, use to advantage clean fuels, and have as low a capital cost as possible. Both fuel supply and thermal pollution considerations that are becoming progressively more important strongly favor the development of a higher temperature, and more efficient, thermodynamic cycle for electric power plants. About 200,000 hr of operation of boiling potassium systems, including over 15,000 hr of potassium vapor turbine operation under the space power plant program, suggest thatmore » a potassium vapor topping cycle with a turbine inlet temperature of approximately 1500/sup 0/F merits consideration. A design study has been carried out to indicate the size, cost, and development problems of the new types of equipment required. The results indicate that a potassium vapor cycle superimposed on a conventional 1050/sup 0/F steam cycle would give an overall thermal efficiency of about 54% as compared to only 40% from a conventional steam cycle. Thus the proposed system would have a fuel consumption only 75% and a heat rejection rate only 50% that of a conventional plant. The system requires clean fuel, and takes advantage of the present trend toward eliminating SO/sub 2/, NO/sub x/ and ash emissions. Surprisingly, at first sight, the assessment at this stage shows that the capital cost may be less than that of a conventional plant. The main reason for this is use of pressurized combustion, which leads to a much smaller combustor, and thin tube walls to contain potassium at about the same pressure.« less
Maximum power point tracker for photovoltaic power plants
NASA Astrophysics Data System (ADS)
Arcidiacono, V.; Corsi, S.; Lambri, L.
The paper describes two different closed-loop control criteria for the maximum power point tracking of the voltage-current characteristic of a photovoltaic generator. The two criteria are discussed and compared, inter alia, with regard to the setting-up problems that they pose. Although a detailed analysis is not embarked upon, the paper also provides some quantitative information on the energy advantages obtained by using electronic maximum power point tracking systems, as compared with the situation in which the point of operation of the photovoltaic generator is not controlled at all. Lastly, the paper presents two high-efficiency MPPT converters for experimental photovoltaic plants of the stand-alone and the grid-interconnected type.
NASA Astrophysics Data System (ADS)
Warmer, F.; Beidler, C. D.; Dinklage, A.; Wolf, R.; The W7-X Team
2016-07-01
As a starting point for a more in-depth discussion of a research strategy leading from Wendelstein 7-X to a HELIAS power plant, the respective steps in physics and engineering are considered from different vantage points. The first approach discusses the direct extrapolation of selected physics and engineering parameters. This is followed by an examination of advancing the understanding of stellarator optimisation. Finally, combining a dimensionless parameter approach with an empirical energy confinement time scaling, the necessary development steps are highlighted. From this analysis it is concluded that an intermediate-step burning-plasma stellarator is the most prudent approach to bridge the gap between W7-X and a HELIAS power plant. Using a systems code approach in combination with transport simulations, a range of possible conceptual designs is analysed. This range is exemplified by two bounding cases, a fast-track, cost-efficient device with low magnetic field and without a blanket and a device similar to a demonstration power plant with blanket and net electricity power production.
Gretzschel, Oliver; Schmitt, Theo G; Hansen, Joachim; Siekmann, Klaus; Jakob, Jürgen
2014-01-01
As a consequence of a worldwide increase of energy costs, the efficient use of sewage sludge as a renewable energy resource must be considered, even for smaller wastewater treatment plants (WWTPs) with design capacities between 10,000 and 50,000 population equivalent (PE). To find the lower limit for an economical conversion of an aerobic stabilisation plant into an anaerobic stabilisation plant, we derived cost functions for specific capital costs and operating cost savings. With these tools, it is possible to evaluate if it would be promising to further investigate refitting aerobic plants into plants that produce biogas. By comparing capital costs with operation cost savings, a break-even point for process conversion could be determined. The break-even point varies depending on project specific constraints and assumptions related to future energy and operation costs and variable interest rates. A 5% increase of energy and operation costs leads to a cost efficient conversion for plants above 7,500 PE. A conversion of WWTPs results in different positive effects on energy generation and plant operations: increased efficiency, energy savings, and on-site renewable power generation by digester gas which can be used in the plant. Also, the optimisation of energy efficiency results in a reduction of primary energy consumption.
NASA Astrophysics Data System (ADS)
Kasharin, D. V.
2017-11-01
The article tackles the issues of designing seasonal water and power supply systems for small recreational facilities in the south of Russia based on intelligent decision support systems. The paper proposes modular prefabricated shell water and power supply works (MPSW&PW) along with energy-efficient standalone water-treatment plants as the principal facilities compliant with the environmental and infrastructural requirements applied to specially protected areas and ensuring the least possible damage to the environment due to a maximum possible use of local construction materials characterized by impressive safety margins in highly seismic environments. The task of designing water and power supply systems requires the consideration of issues pertaining to the development of an intelligent GIS-based system for the selection of water intake sites that facilitate automation of data-processing systems using a priori scanning methods with a variable step and random directions. The paper duly addresses such issues and develops parameterized optimization algorithms for MPSW&PW shell facilities. It equally provides the substantiation of water-treatment plants intelligent design based on energy recovery reverse osmosis and nanofiltration plants that enhance the energy efficiency of such plants serving as the optimum solution for the decentralized water supply of small recreational facilities from renewable energy sources.
NASA Astrophysics Data System (ADS)
Virgen, Matthew Miguel
Two significant goals in solar plant operation are lower cost and higher efficiencies. To achieve those goals, a combined cycle gas turbine (CCGT) system, which uses the hot gas turbine exhaust to produce superheated steam for a bottoming Rankine cycle by way of a heat recovery steam generator (HRSG), is investigated in this work. Building off of a previous gas turbine model created at the Combustion and Solar Energy Laboratory at SDSU, here are added the HRSG and steam turbine model, which had to handle significant change in the mass flow and temperature of air exiting the gas turbine due to varying solar input. A wide range of cases were run to explore options for maximizing both power and efficiency from the proposed CSP CCGT plant. Variable guide vanes (VGVs) were found in the earlier model to be an effective tool in providing operational flexibility to address the variable nature of solar input. Combined cycle efficiencies in the range of 50% were found to result from this plant configuration. However, a combustor inlet temperature (CIT) limit leads to two distinct Modes of operation, with a sharp drop in both plant efficiency and power occurring when the air flow through the receiver exceeded the CIT limit. This drawback can be partially addressed through strategic use of the VGVs. Since system response is fully established for the relevant range of solar input and variable guide vane angles, the System Advisor Model (SAM) from NREL can be used to find what the actual expected solar input would be over the course of the day, and plan accordingly. While the SAM software is not yet equipped to model a Brayton cycle cavity receiver, appropriate approximations were made in order to produce a suitable heliostat field to fit this system. Since the SPHER uses carbon nano-particles as the solar absorbers, questions of particle longevity and how the particles might affect the flame behavior in the combustor were addressed using the chemical kinetics software ChemkinPro by modeling the combustion characteristics both with and without the particles. This work is presented in the Appendix.
Trends and problems in development of the power plants electrical part
NASA Astrophysics Data System (ADS)
Gusev, Yu. P.
2015-03-01
The article discusses some problems relating to development of the electrical part of modern nuclear and thermal power plants, which are stemming from the use of new process and electrical equipment, such as gas turbine units, power converters, and intellectual microprocessor devices in relay protection and automated control systems. It is pointed out that the failure rates of electrical equipment at Russian and foreign power plants tend to increase. The ongoing power plant technical refitting and innovative development processes generate the need to significantly widen the scope of research works on the electrical part of power plants and rendering scientific support to works on putting in use innovative equipment. It is indicated that one of main factors causing the growth of electrical equipment failures is that some of components of this equipment have insufficiently compatible dynamic characteristics. This, in turn may be due to lack or obsolescence of regulatory documents specifying the requirements for design solutions and operation of electric power equipment that incorporates electronic and microprocessor control and protection devices. It is proposed to restore the system of developing new and updating existing departmental regulatory technical documents that existed in the 1970s, one of the fundamental principles of which was placing long-term responsibility on higher schools and leading design institutions for rendering scientific-technical support to innovative development of components and systems forming the electrical part of power plants. This will make it possible to achieve lower failure rates of electrical equipment and to steadily improve the competitiveness of the Russian electric power industry and energy efficiency of generating companies.
Comparison of thermal testing of MS9001FA type GTPs at shatura and nizhnevartovsk GRES
NASA Astrophysics Data System (ADS)
Ol'khovskii, G. G.
2016-11-01
Domestic power plants use combined-cycle plants in which a gas-turbine plant (GTP) and a steam turbine rotate a common electric generator. In this instance, it is impossible to measure the power of each of them, so we have to resort to some assumptions. We have succeeded to check the validity of these assumptions and possible errors of their application testing combined-cycle plants (CCP) with the same GTP and a steam turbine but operating each on its own electrical generator. Comparative tests of a MS901FA GTP of the PGU-400 power-generating unit commissioned at Shatura GRES (a thermal power station) and a GTP of the same type installed at Nizhnevartovsk GRES were performed. As a result of these tests, dependences of the electric power of both gas-turbine plants and a turbine outlet temperature on the inlet temperature were obtained. A relation of the GTP efficiency, heat and air rate on the load are determined, and characteristics of compressors and turbines of both GTPs are defined. The performed tests have confirmed the accuracy of the determined characteristics of the two GTPs using both a direct measurement of net power (Nizhnevartovsk GRES) and an indirect measurement (Shatura GRES).
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mueller, Steffen; Weigel, Robert; Koelpin, Alexander
2015-07-01
Signal conditioning and transmission for sensor systems and networks within the containment of nuclear power plants (NPPs) still poses a challenge to engineers, particularly in the case of equipment upgrades for existing plants, temporary measurements, decommissioning of plants, but also for new builds. This paper presents an innovative method for efficient and cost-effective instrumentation within high dose rate areas inside the containment. A transmitter-receiver topology is proposed that allows simultaneous, unidirectional point-to-point transmission of multiple sensor signals by superimposing them on existing AC or DC power supply cables using power line communication (PLC) technology. Thereby the need for costly installationmore » of additional cables and containment penetrations is eliminated. Based on commercial off-the-shelf (COTS) electronic parts, a radiation hard transmitter is designed to operate in harsh environment within the containment during full plant operation. Hardware modularity of the transmitter allows application specific tradeoffs between redundancy and channel bandwidth. At receiver side in non-radiated areas, signals are extracted from the power line, demodulated, and provided either in analog or digital output format. Laboratory qualification tests and field test results within a boiling water reactor (BWR) are validating the proof of concept of the proposed system. (authors)« less
Investigation of waste heat recovery of binary geothermal plants using single component refrigerants
NASA Astrophysics Data System (ADS)
Unverdi, M.
2017-08-01
In this study, the availability of waste heat in a power generating capacity of 47.4 MW in Germencik Geothermal Power Plant has been investigated via binary geothermal power plant. Refrigerant fluids of 7 different single components such as R-134a, R-152a, R-227ea, R-236fa, R-600, R-143m and R-161 have been selected. The binary cycle has been modeled using the waste heat equaling to mass flow rate of 100 kg/s geothermal fluid. While the inlet temperature of the geothermal fluid into the counter flow heat exchanger has been accepted as 110°C, the outlet temperature has been accepted as 70°C. The inlet conditions have been determined for the refrigerants to be used in the binary cycle. Finally, the mass flow rate of refrigerant fluid and of cooling water and pump power consumption and power generated in the turbine have been calculated for each inlet condition of the refrigerant. Additionally, in the binary cycle, energy and exergy efficiencies have been calculated for 7 refrigerants in the availability of waste heat. In the binary geothermal cycle, it has been found out that the highest exergy destruction for all refrigerants occurs in the heat exchanger. And the highest and lowest first and second law efficiencies has been obtained for R-600 and R-161 refrigerants, respectively.
Geothermal Risk Reduction via Geothermal/Solar Hybrid Power Plants. Final Report
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wendt, Daniel; Mines, Greg; Turchi, Craig
There are numerous technical merits associated with a renewable geothermal-solar hybrid plant concept. The performance of air-cooled binary plants is lowest when ambient temperatures are high due to the decrease in air-cooled binary plant performance that occurs when the working fluid condensing temperature, and consequently the turbine exhaust pressure, increases. Electrical power demand is generally at peak levels during periods of elevated ambient temperature and it is therefore especially important to utilities to be able to provide electrical power during these periods. The time periods in which air-cooled binary geothermal power plant performance is lowest generally correspond to periods ofmore » high solar insolation. Use of solar heat to increase air-cooled geothermal power plant performance during these periods can improve the correlation between power plant output and utility load curves. While solar energy is a renewable energy source with long term performance that can be accurately characterized, on shorter time scales of hours or days it can be highly intermittent. Concentrating solar power (CSP), aka solar-thermal, plants often incorporate thermal energy storage to ensure continued operation during cloud events or after sunset. Hybridization with a geothermal power plant can eliminate the need for thermal storage due to the constant availability of geothermal heat. In addition to the elimination of the requirement for solar thermal storage, the ability of a geothermal/solar-thermal hybrid plant to share a common power block can reduce capital costs relative to separate, stand-alone geothermal and solar-thermal power plant installations. The common occurrence of long-term geothermal resource productivity decline provides additional motivation to consider the use of hybrid power plants in geothermal power production. Geothermal resource productivity decline is a source of significant risk in geothermal power generation. Many, if not all, geothermal resources are subject to decreasing productivity manifested in the form of decreasing production fluid temperature, flow rate, or both during the life span of the associated power generation project. The impacts of geothermal production fluid temperature decline on power plant performance can be significant; a reduction in heat input to a power plant not only decreases the thermal energy available for conversion to electrical power, but also adversely impacts the power plant efficiency. The impact of resource productivity decline on power generation project economics can be equally detrimental. The reduction in power generation is directly correlated to a reduction in revenues from power sales. Further, projects with Power Purchase Agreement (PPA) contracts in place may be subject to significant economic penalties if power generation falls below a specified default level. While the magnitude of PPA penalties varies on a case-by-case basis, it is not unrealistic for these penalties to be on the order of the value of the deficit power sales such that the utility may purchase the power elsewhere. This report evaluates the use of geothermal/solar-thermal hybrid plant technology for mitigation of resource productivity decline, which has not been a primary topic of investigation in previous analyses in the open literature.« less
Microbial fuel cells: Running on gas
NASA Astrophysics Data System (ADS)
Ren, Zhiyong Jason
2017-06-01
Methane is an abundant energy source that is used for power generation in thermal power plants via combustion, but direct conversion to electricity in fuel cells remains challenging. Now, a microbial fuel cell is demonstrated to efficiently convert methane directly to current by careful selection of a consortium of microorganisms.
Liquid-metal binary cycles for stationary power
NASA Technical Reports Server (NTRS)
Gutstein, M.; Furman, E. R.; Kaplan, G. M.
1975-01-01
The use of topping cycles to increase electric power plant efficiency is discussed, with particular attention to mercury and alkali metal Rankine cycle systems that could be considered for topping cycle applications. An overview of this technology, possible system applications, the required development, and possible problem areas is presented.
NASA Technical Reports Server (NTRS)
Rosenberg, L. S.; Revere, W. R.; Selcuk, M. K.
1981-01-01
A computer simulation code was employed to evaluate several generic types of solar power systems (up to 10 MWe). Details of the simulation methodology, and the solar plant concepts are given along with cost and performance results. The Solar Energy Simulation computer code (SESII) was used, which optimizes the size of the collector field and energy storage subsystem for given engine-generator and energy-transport characteristics. Nine plant types were examined which employed combinations of different technology options, such as: distributed or central receivers with one- or two-axis tracking or no tracking; point- or line-focusing concentrator; central or distributed power conversion; Rankin, Brayton, or Stirling thermodynamic cycles; and thermal or electrical storage. Optimal cost curves were plotted as a function of levelized busbar energy cost and annualized plant capacity. Point-focusing distributed receiver systems were found to be most efficient (17-26 percent).
[Avoidance of injuries to migrating fish by hydropower and water intake plants].
Adam, B
2004-03-01
Every year numerous downstream migrating fish are lethally injured by hydro power plants and inlet works. Especially the katadromous Eel (Anguilla anguilla) and anadromous species like Atlantic Salmon (Salmo salar), which have to migrate downstream into the ocean for closing their life cycle, are highly endangered. Due to their specific migratory behavioral pattern, size and morphology conventional protection techniques, like screens do not properly keep them out from getting into the power plant intakes. Despite of the relevance of this problem for ecology and fishing, there are no protection and downstream migration facilities in Europe available, which can efficiently avoid the damage of all species and sizes of downstream migrating fish. Nevertheless according to protect the fish populations it's necessary to use consequently fish protection and downstream migration facilities, i.e. mechanical barrieres or alternative techniques like early warning systems as a prerequisit for a fish-friendly operational management of hydro power plants.
NASA Astrophysics Data System (ADS)
Mehrpooya, Mehdi; Ansarinasab, Hojat; Moftakhari Sharifzadeh, Mohammad Mehdi; Rosen, Marc A.
2017-10-01
An integrated power plant with a net electrical power output of 3.71 × 105 kW is developed and investigated. The electrical efficiency of the process is found to be 60.1%. The process includes three main sub-systems: molten carbonate fuel cell system, heat recovery section and cryogenic carbon dioxide capturing process. Conventional and advanced exergoeconomic methods are used for analyzing the process. Advanced exergoeconomic analysis is a comprehensive evaluation tool which combines an exergetic approach with economic analysis procedures. With this method, investment and exergy destruction costs of the process components are divided into endogenous/exogenous and avoidable/unavoidable parts. Results of the conventional exergoeconomic analyses demonstrate that the combustion chamber has the largest exergy destruction rate (182 MW) and cost rate (13,100 /h). Also, the total process cost rate can be decreased by reducing the cost rate of the fuel cell and improving the efficiency of the combustion chamber and heat recovery steam generator. Based on the total avoidable endogenous cost rate, the priority for modification is the heat recovery steam generator, a compressor and a turbine of the power plant, in rank order. A sensitivity analysis is done to investigate the exergoeconomic factor parameters through changing the effective parameter variations.
Water-carbon trade-off in China's coal power industry.
Zhang, Chao; Anadon, Laura Diaz; Mo, Hongpin; Zhao, Zhongnan; Liu, Zhu
2014-10-07
The energy sector is increasingly facing water scarcity constraints in many regions around the globe, especially in China, where the unprecedented large-scale construction of coal-fired thermal power plants is taking place in its extremely arid northwest regions. As a response to water scarcity, air-cooled coal power plants have experienced dramatic diffusion in China since the middle 2000s. By the end of 2012, air-cooled coal-fired thermal power plants in China amounted to 112 GW, making up 14% of China's thermal power generation capacity. But the water conservation benefit of air-cooled units is achieved at the cost of lower thermal efficiency and consequently higher carbon emission intensity. We estimate that in 2012 the deployment of air-cooled units contributed an additional 24.3-31.9 million tonnes of CO2 emissions (equivalent to 0.7-1.0% of the total CO2 emissions by China's electric power sector), while saving 832-942 million m(3) of consumptive water use (about 60% of the total annual water use of Beijing) when compared to a scenario with water-cooled plants. Additional CO2 emissions from air-cooled plants largely offset the CO2 emissions reduction benefits from Chinese policies of retiring small and outdated coal plants. This water-carbon trade-off is poised to become even more significant by 2020, as air-cooled units are expected to grow by a factor of 2-260 GW, accounting for 22% of China's total coal-fired power generation capacity.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zitney, S.E.
Emerging fossil energy power generation systems must operate with unprecedented efficiency and near-zero emissions, while optimizing profitably amid cost fluctuations for raw materials, finished products, and energy. To help address these challenges, the fossil energy industry will have to rely increasingly on the use advanced computational tools for modeling and simulating complex process systems. In this paper, we present the computational research challenges and opportunities for the optimization of fossil energy power generation systems across the plant lifecycle from process synthesis and design to plant operations. We also look beyond the plant gates to discuss research challenges and opportunities formore » enterprise-wide optimization, including planning, scheduling, and supply chain technologies.« less
Analysis of carbon dioxide emission of gas fuelled cogeneration plant
NASA Astrophysics Data System (ADS)
Nordin, Adzuieen; Amin, M.; Majid, A.
2013-12-01
Gas turbines are widely used for power generation. In cogeneration system, the gas turbine generates electricity and the exhaust heat from the gas turbine is used to generate steam or chilled water. Besides enhancing the efficiency of the system, the process assists in reducing the emission of CO2 to the environment. This study analyzes the amount of CO2 emission by Universiti Teknologi Petronas gas fuelled cogeneration system using energy balance equations. The results indicate that the cogeneration system reduces the CO2 emission to the environment by 60%. This finding could encourage the power plant owners to install heat recovery systems to their respective plants.
Projection of distributed-collector solar-thermal electric power plant economics to years 1990-2000
NASA Technical Reports Server (NTRS)
Fujita, T.; Elgabalawi, N.; Herrera, G.; Turner, R. H.
1977-01-01
A preliminary comparative evaluation of distributed-collector solar thermal power plants was undertaken by projecting power plant economics of selected systems to the 1990 to 2000 time frame. The selected systems include: (1) fixed orientation collectors with concentrating reflectors and vacuum tube absorbers, (2) one axis tracking linear concentrator including parabolic trough and variable slat designs, and (3) two axis tracking parabolic dish systems including concepts with small heat engine-electric generator assemblies at each focal point as well as approaches having steam generators at the focal point with pipeline collection to a central power conversion unit. Comparisons are presented primarily in terms of energy cost and capital cost over a wide range of operating load factors. Sensitvity of energy costs for a range of efficiency and cost of major subsystems/components is presented to delineate critical technological development needs.
NASA Astrophysics Data System (ADS)
Butler, Thomas S.
Throughout the United States the electric utility industry is restructuring in response to federal legislation mandating deregulation. The electric utility industry has embarked upon an extraordinary experiment by restructuring in response to deregulation that has been advocated on the premise of improving economic efficiency by encouraging competition in as many sectors of the industry as possible. However, unlike the telephone, trucking, and airline industries, the potential effects of electric deregulation reach far beyond simple energy economics. This dissertation presents the potential safety risks involved with the deregulation of the electric power industry in the United States and abroad. The pressures of a competitive environment on utilities with nuclear power plants in their portfolio to lower operation and maintenance costs could squeeze them to resort to some risky cost-cutting measures. These include deferring maintenance, reducing training, downsizing staff, excessive reductions in refueling down time, and increasing the use of on-line maintenance. The results of this study indicate statistically significant differences at the .01 level between the safety of pressurized water reactor nuclear power plants and boiling water reactor nuclear power plants. Boiling water reactors exhibited significantly more problems than did pressurized water reactors.
Solid Oxide Fuel Cell Hybrid System for Distributed Power Generation
DOE Office of Scientific and Technical Information (OSTI.GOV)
David Deangelis; Rich Depuy; Debashis Dey
2004-09-30
This report summarizes the work performed by Hybrid Power Generation Systems, LLC (HPGS) during the April to October 2004 reporting period in Task 2.3 (SOFC Scaleup for Hybrid and Fuel Cell Systems) under Cooperative Agreement DE-FC26-01NT40779 for the U. S. Department of Energy, National Energy Technology Laboratory (DOE/NETL), entitled ''Solid Oxide Fuel Cell Hybrid System for Distributed Power Generation''. This study analyzes the performance and economics of power generation systems for central power generation application based on Solid Oxide Fuel Cell (SOFC) technology and fueled by natural gas. The main objective of this task is to develop credible scale upmore » strategies for large solid oxide fuel cell-gas turbine systems. System concepts that integrate a SOFC with a gas turbine were developed and analyzed for plant sizes in excess of 20 MW. A 25 MW plant configuration was selected with projected system efficiency of over 65% and a factory cost of under $400/kW. The plant design is modular and can be scaled to both higher and lower plant power ratings. Technology gaps and required engineering development efforts were identified and evaluated.« less
Environmentally Clean Mitigation of Undesirable Plant Life Using Lasers
DOE Office of Scientific and Technical Information (OSTI.GOV)
Rubenchik, A M; McGrann, T J; Yamamoto, R M
This concept comprises a method for environmentally clean destruction of undesirable plant life using visible or infrared radiation. We believe that during the blossom stage, plant life is very sensitive to electromagnetic radiation, with an enhanced sensitivity to specific spectral ranges. Small doses of irradiation can arrest further plant growth, cause flower destruction or promote plant death. Surrounding plants, which are not in the blossoming stage, should not be affected. Our proposed mechanism to initiate this effect is radiation produced by a laser. Tender parts of the blossom possess enhanced absorptivity in some spectral ranges. This absorption can increase themore » local tissue temperature by several degrees, which is sufficient to induce bio-tissue damage. In some instances, the radiation may actually stimulate plant growth, as an alternative for use in increased crop production. This would be dependent on factors such as plant type, the wavelength of the laser radiation being used and the amount of the radiation dose. Practical, economically viable realization of this concept is possible today with the advent of high efficiency, compact and powerful laser diodes. The laser diodes provide an efficient, environmentally clean source of radiation at a variety of power levels and radiation wavelengths. Figure 1 shows the overall concept, with the laser diodes mounted on a movable platform, traversing and directing the laser radiation over a field of opium poppies.« less
Some methods for achieving more efficient performance of fuel assemblies
NASA Astrophysics Data System (ADS)
Boltenko, E. A.
2014-07-01
More efficient operation of reactor plant fuel assemblies can be achieved through the use of new technical solutions aimed at obtaining more uniform distribution of coolant over the fuel assembly section, more intense heat removal on convex heat-transfer surfaces, and higher values of departure from nucleate boiling ratio (DNBR). Technical solutions using which it is possible to obtain more intense heat removal on convex heat-transfer surfaces and higher DNBR values in reactor plant fuel assemblies are considered. An alternative heat removal arrangement is described using which it is possible to obtain a significantly higher power density in a reactor plant and essentially lower maximal fuel rod temperature.
NASA Astrophysics Data System (ADS)
Post, Alexander; Beath, Andrew; Sauret, Emilie; Persky, Rodney
2017-06-01
Concentrated solar thermal power generation poses a unique situation for power block selection, in which a capital intensive heat source is subject to daily and seasonal fluctuations in intensity. In this study, a method is developed to easily evaluate the favourability of different power blocks for converting the heat supplied by a concentrated solar thermal plant into power at the 100MWe scale based on several key parameters. The method is then applied to a range of commercially available power cycles that operate over different temperatures and efficiencies, and with differing capital costs, each with performance and economic parameters selected to be typical of their technology type, as reported in literature. Using this method, the power cycle is identified among those examined that is most likely to result in a minimum levelised cost of energy of a solar thermal plant.
NASA Astrophysics Data System (ADS)
Aminov, R. Z.; Khrustalev, V. A.; Portyankin, A. V.
2015-02-01
The effectiveness of combining nuclear power plants equipped with water-cooled water-moderated power-generating reactors (VVER) with other sources of energy within unified power-generating complexes is analyzed. The use of such power-generating complexes makes it possible to achieve the necessary load pickup capability and flexibility in performing the mandatory selective primary and emergency control of load, as well as participation in passing the night minimums of electric load curves while retaining high values of the capacity utilization factor of the entire power-generating complex at higher levels of the steam-turbine part efficiency. Versions involving combined use of nuclear power plants with hydrogen toppings and gas turbine units for generating electricity are considered. In view of the fact that hydrogen is an unsafe energy carrier, the use of which introduces additional elements of risk, a procedure for evaluating these risks under different conditions of implementing the fuel-and-hydrogen cycle at nuclear power plants is proposed. Risk accounting technique with the use of statistical data is considered, including the characteristics of hydrogen and gas pipelines, and the process pipelines equipment tightness loss occurrence rate. The expected intensities of fires and explosions at nuclear power plants fitted with hydrogen toppings and gas turbine units are calculated. In estimating the damage inflicted by events (fires and explosions) occurred in nuclear power plant turbine buildings, the US statistical data were used. Conservative scenarios of fires and explosions of hydrogen-air mixtures in nuclear power plant turbine buildings are presented. Results from calculations of the introduced annual risk to the attained net annual profit ratio in commensurable versions are given. This ratio can be used in selecting projects characterized by the most technically attainable and socially acceptable safety.
SOXAL{trademark} pilot plant demonstration at Niagara Mohawk`s Dunkirk Station
DOE Office of Scientific and Technical Information (OSTI.GOV)
Strangway, P.K.
This paper describes a six-month, nominal three megawatt (3 MW) pilot plant demonstration of the SOXAL{trademark} regenerative flue gas desulfurization (FGD) process at Niagara Mohawk Power Corporation`s Dunkirk, NY coal-fired power station. Using a slip-stream of flue gas from an actual coal-fired boiler, the pilot plant successfully demonstrated the absorption of sulfur dioxide and the simultaneous regeneration of sodium-based scrubbing liquor via bipolar membrane electrodialysis. Sulfur dioxide removal efficiency of greater than 98% was routinely achieved. The absorption and regeneration stages were both proven reliable and controllable. The pilot plant was successfully operated in both continuous and decoupled modes ofmore » operation, thus demonstrating the flexibility of this process.« less
Power-plant modernization program in Latvia. Desk Study Report No. 1. Export trade information
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
1992-08-01
The Government of Latvia has requested the U.S. Trade and Development Program's (TDP's) assistance in financing the cost of a feasibility study to develop a modernization program for its thermal power stations aimed at improving their performance and efficiency. The consultant will work with engineers and managers of Latvenergo, Latvia's power utility, to review the performance of the country's two thermal power stations and carry out a detailed study for the rehabilitation and modernization of the TEC-2 thermal power station in Riga. The overall goal of the program will be to maximize the output capacity of the country's two powermore » stations through the implementation of economically efficient rehabilitation projects.« less
Power processing and control requirements of dispersed solar thermal electric generation systems
NASA Technical Reports Server (NTRS)
Das, R. L.
1980-01-01
Power Processing and Control requirements of Dispersed Receiver Solar Thermal Electric Generation Systems are presented. Kinematic Stirling Engines, Brayton Engines and Rankine Engines are considered as prime movers. Various types of generators are considered for ac and dc link generations. It is found that ac-ac Power Conversion is not suitable for implementation at this time. It is also found that ac-dc-ac Power Conversion with a large central inverter is more efficient than ac-dc-ac Power Conversion using small dispersed inverters. Ac-link solar thermal electric plants face potential stability and synchronization problems. Research and development efforts are needed in improving component performance characteristics and generation efficiency to make Solar Thermal Electric Generation economically attractive.
Flow Control in Wells Turbines for Harnessing Maximum Wave Power.
Lekube, Jon; Garrido, Aitor J; Garrido, Izaskun; Otaola, Erlantz; Maseda, Javier
2018-02-10
Oceans, and particularly waves, offer a huge potential for energy harnessing all over the world. Nevertheless, the performance of current energy converters does not yet allow us to use the wave energy efficiently. However, new control techniques can improve the efficiency of energy converters. In this sense, the plant sensors play a key role within the control scheme, as necessary tools for parameter measuring and monitoring that are then used as control input variables to the feedback loop. Therefore, the aim of this work is to manage the rotational speed control loop in order to optimize the output power. With the help of outward looking sensors, a Maximum Power Point Tracking (MPPT) technique is employed to maximize the system efficiency. Then, the control decisions are based on the pressure drop measured by pressure sensors located along the turbine. A complete wave-to-wire model is developed so as to validate the performance of the proposed control method. For this purpose, a novel sensor-based flow controller is implemented based on the different measured signals. Thus, the performance of the proposed controller has been analyzed and compared with a case of uncontrolled plant. The simulations demonstrate that the flow control-based MPPT strategy is able to increase the output power, and they confirm both the viability and goodness.
Flow Control in Wells Turbines for Harnessing Maximum Wave Power
Garrido, Aitor J.; Garrido, Izaskun; Otaola, Erlantz; Maseda, Javier
2018-01-01
Oceans, and particularly waves, offer a huge potential for energy harnessing all over the world. Nevertheless, the performance of current energy converters does not yet allow us to use the wave energy efficiently. However, new control techniques can improve the efficiency of energy converters. In this sense, the plant sensors play a key role within the control scheme, as necessary tools for parameter measuring and monitoring that are then used as control input variables to the feedback loop. Therefore, the aim of this work is to manage the rotational speed control loop in order to optimize the output power. With the help of outward looking sensors, a Maximum Power Point Tracking (MPPT) technique is employed to maximize the system efficiency. Then, the control decisions are based on the pressure drop measured by pressure sensors located along the turbine. A complete wave-to-wire model is developed so as to validate the performance of the proposed control method. For this purpose, a novel sensor-based flow controller is implemented based on the different measured signals. Thus, the performance of the proposed controller has been analyzed and compared with a case of uncontrolled plant. The simulations demonstrate that the flow control-based MPPT strategy is able to increase the output power, and they confirm both the viability and goodness. PMID:29439408
Agarwal, Vivek; Buttles, John W.; Beaty, Lawrence H.; ...
2016-10-05
In the current competitive energy market, the nuclear industry is committed to lower the operations and maintenance cost; increase productivity and efficiency while maintaining safe and reliable operation. The present operating model of nuclear power plants is dependent on large technical staffs that put the nuclear industry at long-term economic disadvantage. Technology can play a key role in nuclear power plant configuration management in offsetting labor costs by automating manually performed plant activities. The technology being developed, tested, and demonstrated in this paper will enable the continued safe operation of today’s fleet of light water reactors by providing the technicalmore » means to monitor components in plants today that are only routinely monitored through manual activities. The wireless enabled valve position indicators that are the subject of this paper are able to provide a valid position indication available continuously, rather than only periodically. As a result, a real-time (online) availability of valve positions using an affordable technologies are vital to plant configuration when compared with long-term labor rates, and provide information that can be used for a variety of plant engineering, maintenance, and management applications.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Agarwal, Vivek; Buttles, John W.; Beaty, Lawrence H.
In the current competitive energy market, the nuclear industry is committed to lower the operations and maintenance cost; increase productivity and efficiency while maintaining safe and reliable operation. The present operating model of nuclear power plants is dependent on large technical staffs that put the nuclear industry at long-term economic disadvantage. Technology can play a key role in nuclear power plant configuration management in offsetting labor costs by automating manually performed plant activities. The technology being developed, tested, and demonstrated in this paper will enable the continued safe operation of today’s fleet of light water reactors by providing the technicalmore » means to monitor components in plants today that are only routinely monitored through manual activities. The wireless enabled valve position indicators that are the subject of this paper are able to provide a valid position indication available continuously, rather than only periodically. As a result, a real-time (online) availability of valve positions using an affordable technologies are vital to plant configuration when compared with long-term labor rates, and provide information that can be used for a variety of plant engineering, maintenance, and management applications.« less
NASA Astrophysics Data System (ADS)
Hotta, Arto
During recent years, once-through supercritical (OTSC) CFB technology has been developed, enabling the CFB technology to proceed to medium-scale (500 MWe) utility projects such as Łagisza Power Plant in Poland owned by Poludniowy Koncern Energetyczny SA. (PKE), with net efficiency nearly 44%. Łagisza power plant is currently under commissioning and has reached full load operation in March 2009. The initial operation shows very good performance and confirms, that the CFB process has no problems with the scaling up to this size. Also the once-through steam cycle utilizing Siemens' vertical tube Benson technology has performed as predicted in the CFB process. Foster Wheeler has developed the CFB design further up to 800 MWe with net efficiency of ≥45%.
Yi, Honghong; Hao, Jiming; Duan, Lei; Li, Xinghua; Guo, Xingming
2006-09-01
In this investigation, the collection efficiency of particulate emission control devices (PECDs), particulate matter (PM) emissions, and PM size distribution were determined experimentally at the inlet and outlet of PECDs at five coal-fired power plants. Different boilers, coals, and PECDs are used in these power plants. Measurement in situ was performed by an electrical low-pressure impactor with a sampling system, which consisted of an isokinetic sampler probe, precut cyclone, and two-stage dilution system with a sample line to the instruments. The size distribution was measured over a range from 0.03 to 10 microm. Before and after all of the PECDs, the particle number size distributions display a bimodal distribution. The PM2.5 fraction emitted to atmosphere includes a significant amount of the mass from the coarse particle mode. The controlled and uncontrolled emission factors of total PM, inhalable PM (PM10), and fine PM P(M2.5) were obtained. Electrostatic precipitator (ESP) and baghouse total collection efficiencies are 96.38-99.89% and 99.94%, respectively. The minimum collection efficiency of the ESP and the baghouse both appear in the particle size range of 0.1-1 microm. In this size range, ESP and baghouse collection efficiencies are 85.79-98.6% and 99.54%. Real-time measurement shows that the mass and number concentration of PM10 will be greatly affected by the operating conditions of the PECDs. The number of emitted particles increases with increasing boiler load level because of higher combustion temperature. During test run periods, the data reproducibility is satisfactory.
Eco-development and energy efficient technologies in Russia: prospects and reality
NASA Astrophysics Data System (ADS)
Kurakova, Oksana
2017-10-01
The article highlights the concept of eco-standards in Russia, and discusses new technologies that allow to build energy-efficient houses in the form of countryside real estate. Special attention is given to the principle of heat production based on the use of individual facilities, power centers mini thermal power plants, as well as to ways to reduce water consumption at home. Presents analysis of the advantages projects “built-to-suit” for the introduction of the energy efficient technologies. Justified idea and principles of “green construction” in Russia in the real estate market. Conclusion about the effectiveness of the use, opportunities and development of energy efficient technologies.
A summary of the ECAS performance and cost results for MHD systems
NASA Technical Reports Server (NTRS)
Seikel, G. R.; Sovie, R. J.; Burns, R. K.; Barna, G. J.; Burkhart, J. A.; Nainiger, J. J.; Smith, J. M.
1976-01-01
The potential is examined of various advanced power plant concepts using coal and coal-derived fuel. The results indicate that open cycle coal fired direct preheat MHD systems have potentially one of the highest coal-pile-to-bus-bar efficiencies and also one of the lowest costs of electricity (COE) of the systems studied. Closed cycle MHD systems may have the potential to approach the efficiency and COE of open cycle MHD. The 1200-1500 F liquid metal MHD systems studied do not appear to have the potential of exceeding the efficiency or competing with the COE of advanced steam plants.
NASA Astrophysics Data System (ADS)
Hnydiuk-Stefan, Anna; Składzień, Jan
2015-03-01
The paper examines from the thermodynamic point of view operation of coal fired power unit cooperating with the cryogenic oxygen unit, with a particular emphasis on the characteristic performance parameters of the oxygen unit. The relatively high purity technical oxygen produced in the oxygen unit is then used as the oxidant in the fluidized bed boiler of the modern coal fired power unit with electric power output of approximately 460 MW. The analyzed oxygen unit has a classical two-column structure with an expansion turbine (turboexpander), which allows the use of relatively low pressure initially compressed air. Multivariant calculations were performed, the main result being the loss of power and efficiency of the unit due to the need to ensure adequate driving power to the compressor system of the oxygen generating plant.
Solving large scale unit dilemma in electricity system by applying commutative law
NASA Astrophysics Data System (ADS)
Legino, Supriadi; Arianto, Rakhmat
2018-03-01
The conventional system, pooling resources with large centralized power plant interconnected as a network. provides a lot of advantages compare to the isolated one include optimizing efficiency and reliability. However, such a large plant need a huge capital. In addition, more problems emerged to hinder the construction of big power plant as well as its associated transmission lines. By applying commutative law of math, ab = ba, for all a,b €-R, the problem associated with conventional system as depicted above, can be reduced. The idea of having small unit but many power plants, namely “Listrik Kerakyatan,” abbreviated as LK provides both social and environmental benefit that could be capitalized by using proper assumption. This study compares the cost and benefit of LK to those of conventional system, using simulation method to prove that LK offers alternative solution to answer many problems associated with the large system. Commutative Law of Algebra can be used as a simple mathematical model to analyze whether the LK system as an eco-friendly distributed generation can be applied to solve various problems associated with a large scale conventional system. The result of simulation shows that LK provides more value if its plants operate in less than 11 hours as peaker power plant or load follower power plant to improve load curve balance of the power system. The result of simulation indicates that the investment cost of LK plant should be optimized in order to minimize the plant investment cost. This study indicates that the benefit of economies of scale principle does not always apply to every condition, particularly if the portion of intangible cost and benefit is relatively high.
Sun-to-Wheels Exergy Efficiencies for Bio-Ethanol and Photovoltaics.
Williams, Eric; Sekar, Ashok; Matteson, Schuyler; Rittmann, Bruce E
2015-06-02
The two main paths to power vehicles with sunlight are to use photosynthesis to grow biomass, converting to a liquid fuel for an internal combustion engine or to generate photovoltaic electricity that powers the battery of an electric vehicle. While the environmental attributes of these two paths have been much analyzed, prior studies consider the current state of technology. Technologies for biofuel and photovoltaic paths are evolving; it is critical to consider how progress might improve environmental performance. We address this challenge by assessing the current and maximum theoretical exergy efficiencies of bioethanol and photovoltaic sun-to-wheels process chains. The maximum theoretical efficiency is an upper bound stipulated by physical laws. The current net efficiency to produce motive power from silicon photovoltaic modules is estimated at 5.4%, much higher than 0.03% efficiency for corn-based ethanol. Flat-plate photovoltaic panels also have a much higher theoretical maximum efficiency than a C4 crop plant, 48% versus 0.19%. Photovoltaic-based power will always be vastly more efficient than a terrestrial crop biofuel. Providing all mobility in the U.S. via crop biofuels would require 130% of arable land with current technology and 20% in the thermodynamic limit. Comparable values for photovoltaic-based power are 0.7% and 0.081%, respectively.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
1991-11-01
The National Power Corporation (NAPCOR) of Philippines has requested the Trade and Development Program (TDP) to fund a study to evaluate the technical and economic feasibility of converting its existing oil and coal fired power plants to natural gas. The decision to undertake the study resulted from preliminary information on a large gas find off the coast of Palawan island. However, a second exploration well has come up dry. Now, the conversion of the existing power plants to natural gas seems very questionable. Even if the proven gas reserves prove to be commercially viable, the gas will not be availablemore » until 1998 or later for utilization. At that time several of NAPCOR's plants would have aged further, the political and economic situation in Philippines could have altered significantly, possibly improved, private power companies might be able to use the gas more efficiently by building state-of-the-art combined cycle power plants which will make more economic sense than converting existing old boilers to natural gas. In addition, most of the existing power equipment was manufactured by Japanese and/or European firms. It makes sense for NAPCOR to solicit services from these firms if it decides to go ahead with the implementation of the power plant conversion project. The potential for any follow on work for U.S. businesses is minimal to zero in the thermal conversion project. Therefore, at this time, TDP funding for the feasibility would be premature and not recommended.« less
Climate and water resource change impacts and adaptation potential for US power supply
Miara, Ariel; Macknick, Jordan E.; Vorosmarty, Charles J.; ...
2017-10-30
Power plants that require cooling currently (2015) provide 85% of electricity generation in the United States. These facilities need large volumes of water and sufficiently cool temperatures for optimal operations, and projected climate conditions may lower their potential power output and affect reliability. We evaluate the performance of 1,080 thermoelectric plants across the contiguous US under future climates (2035-2064) and their collective performance at 19 North American Electric Reliability Corporation (NERC) sub-regions. Joint consideration of engineering interactions with climate, hydrology and environmental regulations reveals the region-specific performance of energy systems and the need for regional energy security and climate-water adaptationmore » strategies. Despite climate-water constraints on individual plants, the current power supply infrastructure shows potential for adaptation to future climates by capitalizing on the size of regional power systems, grid configuration and improvements in thermal efficiencies. Without placing climate-water impacts on individual plants in a broader power systems context, vulnerability assessments that aim to support adaptation and resilience strategies misgauge the extent to which regional energy systems are vulnerable. As a result, climate-water impacts can lower thermoelectric reserve margins, a measure of systems-level reliability, highlighting the need to integrate climate-water constraints on thermoelectric power supply into energy planning, risk assessments, and system reliability management.« less
Climate and water resource change impacts and adaptation potential for US power supply
NASA Astrophysics Data System (ADS)
Miara, Ariel; Macknick, Jordan E.; Vörösmarty, Charles J.; Tidwell, Vincent C.; Newmark, Robin; Fekete, Balazs
2017-11-01
Power plants that require cooling currently (2015) provide 85% of electricity generation in the United States. These facilities need large volumes of water and sufficiently cool temperatures for optimal operations, and projected climate conditions may lower their potential power output and affect reliability. We evaluate the performance of 1,080 thermoelectric plants across the contiguous US under future climates (2035-2064) and their collective performance at 19 North American Electric Reliability Corporation (NERC) sub-regions. Joint consideration of engineering interactions with climate, hydrology and environmental regulations reveals the region-specific performance of energy systems and the need for regional energy security and climate-water adaptation strategies. Despite climate-water constraints on individual plants, the current power supply infrastructure shows potential for adaptation to future climates by capitalizing on the size of regional power systems, grid configuration and improvements in thermal efficiencies. Without placing climate-water impacts on individual plants in a broader power systems context, vulnerability assessments that aim to support adaptation and resilience strategies misgauge the extent to which regional energy systems are vulnerable. Climate-water impacts can lower thermoelectric reserve margins, a measure of systems-level reliability, highlighting the need to integrate climate-water constraints on thermoelectric power supply into energy planning, risk assessments, and system reliability management.
Climate and water resource change impacts and adaptation potential for US power supply
DOE Office of Scientific and Technical Information (OSTI.GOV)
Miara, Ariel; Macknick, Jordan E.; Vorosmarty, Charles J.
Power plants that require cooling currently (2015) provide 85% of electricity generation in the United States. These facilities need large volumes of water and sufficiently cool temperatures for optimal operations, and projected climate conditions may lower their potential power output and affect reliability. We evaluate the performance of 1,080 thermoelectric plants across the contiguous US under future climates (2035-2064) and their collective performance at 19 North American Electric Reliability Corporation (NERC) sub-regions. Joint consideration of engineering interactions with climate, hydrology and environmental regulations reveals the region-specific performance of energy systems and the need for regional energy security and climate-water adaptationmore » strategies. Despite climate-water constraints on individual plants, the current power supply infrastructure shows potential for adaptation to future climates by capitalizing on the size of regional power systems, grid configuration and improvements in thermal efficiencies. Without placing climate-water impacts on individual plants in a broader power systems context, vulnerability assessments that aim to support adaptation and resilience strategies misgauge the extent to which regional energy systems are vulnerable. As a result, climate-water impacts can lower thermoelectric reserve margins, a measure of systems-level reliability, highlighting the need to integrate climate-water constraints on thermoelectric power supply into energy planning, risk assessments, and system reliability management.« less
NASA Astrophysics Data System (ADS)
Kumar, Ashish; Chatterjee, Snehamoy
2017-05-01
Production scheduling is a crucial aspect of the mining industry. An optimal and efficient production schedule can increase the profits manifold and reduce the amount of waste to be handled. Production scheduling for coal mines is necessary to maintain consistency in the quality and quantity parameters of coal supplied to power plants. Irregularity in the quality parameters of the coal can lead to heavy losses in coal-fired power plants. Moreover, the stockpiling of coal poses environmental and fire problems owing to low incubation periods. This article proposes a production scheduling formulation for open-pit coal mines including stockpiling and blending opportunities, which play a major role in maintaining the quality and quantity of supplied coal. The proposed formulation was applied to a large open-pit coal mine in India. This contribution provides an efficient production scheduling formulation for coal mines after utilizing the stockpile coal within the incubation periods with the maximization of discounted cash flows. At the same time, consistency is maintained in the quality and quantity of coal to power plants through blending and stockpiling options to ensure smooth functioning.
NREL: News - NREL Wins Research and Development Awards
and chemicals, energy-efficient buildings, advanced vehicle design, geothermal energy and hydrogen the U.S. Department of Energy's National Renewable Energy Laboratory (NREL) are among this year's 100 components in geothermal power plants; a solar power system that produces electricity while still allowing
Energy 101: Concentrating Solar Power
None
2018-02-07
From towers to dishes to linear mirrors to troughs, concentrating solar power (CSP) technologies reflect and collect solar heat to generate electricity. A single CSP plant can generate enough power for about 90,000 homes. This video explains what CSP is, how it works, and how systems like parabolic troughs produce renewable power. For more information on the Office of Energy Efficiency and Renewable Energy's CSP research, see the Solar Energy Technology Program's Concentrating Solar Power Web page at http://www1.eere.energy.gov/solar/csp_program.html.
Activity and accomplishments of dish/Stirling electric power system development
NASA Technical Reports Server (NTRS)
Livingston, F. R.
1985-01-01
The development of the solar parabolic-dish/Stirling-engine electricity generating plant known as the dish/Stirling electric power system is described. The dish/Stirling electric power system converts sunlight to electricity more efficiently than any known existing solar electric power system. The fabrication and characterization of the test bed concentrators that were used for Stirling module testing and of the development of parabolic dish concentrator No. 2, an advanced solar concentrator unit considered for use with the Stirling power conversion unit is discussed.
NASA Astrophysics Data System (ADS)
Alkhasov, A. B.; Alkhasova, D. A.
2018-02-01
The article substantiates the possibility of efficiently harnessing the geothermal resources available in the North Caucasian region through constructing binary geothermal power plants (GeoTPPs) using idle petroleum and gas wells. The power capacities of GeoTPPs are evaluated, and the basic characteristics of these power plants in case of constructing them in the promising areas are determined. The overall useful GeoTPP capacity equal to approximately 330 MW can be obtained from using the entire fleet of idle wells available in these areas. Diagrams confirming the possibility of reaching the optimal flowrate of geothermal heat carrier circulating in the geothermal circulation system loop are presented. This flowrate corresponds to a binary GeoTPP's maximal useful power output. The article shows, taking the Ternair geothermal field as an example, that it is inefficient to use medium-enthalpy thermal waters for generating energy at a binary GeoTPP involving reinjection of a spent heat carrier. It is shown that good prospects can be expected from applying a hybrid geothermal and combined-cycle technology, by means of which it is possible to use lowenthalpy (80-100°C) thermal waters for generating electricity in a highly efficient manner. In accordance with such technology, geothermal heat is used in the binary GeoTPP cycle for heating low-boiling working fluid to its evaporation temperature. The working fluid is evaporated and superheated by using the heat of exhaust gases from a gas turbine power unit. Owing to combined use of the thermal water heat potential and the heat of exhaust gases from a gas turbine power plant in a hybrid process system, it becomes possible to obtain high power performance indicators of hybrid geothermal and combined-cycle power plants. This conclusion is confirmed by the results from numerical evaluations carried out as applied to the Ternair geothermal field. With the fully harnessed resource potential of the Ternair field, the total capacity of hybrid geothermal and combined-cycle power plants may reach 60 MW, a level that would make it possible to relieve a significant part of energy, environmental, economic, and social problems faced by the city of Makhachkala.
NASA Astrophysics Data System (ADS)
Shahzad, Muhammad Wakil; Ng, Kim Choon; Thu, Kyaw
2016-06-01
Power and desalination cogeneration plants are common in many water scared courtiers. Designers and planners for cogeneration face tough challenges in deciding the options:- Is it better to operate a power plant (PP) with the reverse osmosis (i.e., PP+RO) or the thermally-driven multi-effect distillation/multi-stage flashed (PP+MED/MSF) methods. From literature, the RO methods are known to be energy efficient whilst the MED/MSF are known to have excellent thermodynamic synergies as only low pressure and temperature steam are used. Not with-standing the challenges of severe feed seawater of the Gulf, such as the frequent harmful algae blooms (HABs) and high silt contents, this presentation presents a quantitative analyses using the exergy and energetic approaches in evaluating the performances of a real cogeneration plant that was recently proposed in the eastern part of Saudi Arabia. We demonstrate that the process choice of PP+RO versus PP+MED depends on the inherent efficiencies of individual process method which is closely related to innovative process design. In this connection, a method of primary fuel cost apportionment for a co-generation plant with a MED desalination is presented. We show that an energy approach, that captures the quality of expanding steam, is a better method over the conventional work output (energetic) and the energy method seems to be over-penalizing a thermally-driven MED by as much as 22% in the operating cost of water.
Effect of calcium formate as an additive on desulfurization in power plants.
Li, Zhenhua; Xie, Chunfang; Lv, Jing; Zhai, Ruiguo
2018-05-01
SO 2 in flue gas needs to be eliminated to alleviate air pollution. As the quality of coal decreases and environmental standard requirements become more stringent, the high-efficiency desulfurization of flue gas faces more and more challenges. As an economical and environmentally friendly solution, the effect of calcium formate as an additive on desulfurization efficiency in the wet flue gas desulfurization (WFGD) process was studied for the first time. Improvement of the desulfurization efficiency was achieved with limited change in pH after calcium formate was added into the reactor, and it was found to work better than other additives tested. The positive effects were further verified in a power plant, which showed that adding calcium formate could promote the dissolution of calcium carbonate, accelerate the growth of gypsum crystals and improve the efficiency of desulfurization. Thus, calcium formate was proved to be an effective additive and can potentially be used to reduce the amount of limestone slurry required, as well as the energy consumption and operating costs in industrial desulfurization. Copyright © 2017. Published by Elsevier B.V.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chattopadhyay, S., E-mail: suman.mech09@gmail.com; Mondal, P., E-mail: mondal.pradip87@gmail.com; Ghosh, S., E-mail: sudipghosh.becollege@gmail.com
Thermal performance analysis and sizing of a biomass gasification based combined power and refrigeration plant (CPR) is reported in this study. The plant is capable of producing 100 kWe of electrical output while simultaneously producing a refrigeration effect, varying from 28-68 ton of refrigeration (TR). The topping gas turbine cycle is an indirectly heated all-air cycle. A combustor heat exchanger duplex (CHX) unit burns producer gas and transfer heat to air. This arrangement avoids complex gas cleaning requirements for the biomass-derived producer gas. The exhaust air of the topping GT is utilized to run a bottoming ammonia absorption refrigeration (AAR)more » cycle via a heat recovery steam generator (HRSG), steam produced in the HRSG supplying heat to the generator of the refrigeration cycle. Effects of major operating parameters like topping cycle pressure ratio (r{sub p}) and turbine inlet temperature (TIT) on the energetic performance of the plant are studied. Energetic performance of the plant is evaluated via energy efficiency, required biomass consumption and fuel energy savings ratio (FESR). The FESR calculation method is significant for indicating the savings in fuel of a combined power and process heat plant instead of separate plants for power and process heat. The study reveals that, topping cycle attains maximum power efficiency of 30%in pressure ratio range of 8-10. Up to a certain value of pressure ratio the required air flow rate through the GT unit decreases with increase in pressure ratio and then increases with further increase in pressure ratio. The capacity of refrigeration of the AAR unit initially decreases up to a certain value of topping GT cycle pressure ratio and then increases with further increase in pressure ratio. The FESR is found to be maximized at a pressure ratio of 9 (when TIT=1100°C), the maximum value being 53%. The FESR is higher for higher TIT. The heat exchanger sizing is also influenced by the topping cycle pressure ratio and GT-TIT.« less
NASA Astrophysics Data System (ADS)
Iakovleva, E. V.; Momot, B. A.
2017-10-01
The object of this study is to develop a power plant and an electric propulsion control system for autonomous remotely controlled vessels. The tasks of the study are as follows: to assess remotely controlled vessels usage reasonability, to define the requirements for this type of vessel navigation. In addition, the paper presents the analysis of technical diagnostics systems. The developed electric propulsion control systems for vessels should provide improved reliability and efficiency of the propulsion complex to ensure the profitability of remotely controlled vessels.
2015-11-01
energy efficiency.25 The rules are scheduled to go into effect in 2016. One of the toughest components for coal power plants to meet will be the NOx...coal power plants out of business by the early-2020s.30 High Cost and Other Challenges of Renewables. Renewable energy has been a focus of the envi...will be explained later in detail. Coal: An Environmentally Problematic Energy Source. Besides CO2 emissions, burning coal pollutes the environment
NASA Technical Reports Server (NTRS)
Amos, D. J.; Grube, J. E.
1976-01-01
Open-cycle recuperated gas turbine plant with inlet temperatures of 1255 to 1644 K (1800 to 2500 F) and recuperators with effectiveness values of 0, 70, 80 and 90% are considered. A 1644 K (2500 F) gas turbine would have a 33.5% plant efficiency in a simple cycle, 37.6% in a recuperated cycle and 47.6% when combined with a sulfur dioxide bottomer. The distillate burning recuperated plant was calculated to produce electricity at a cost of 8.19 mills/MJ (29.5 mills/kWh). Due to their low capital cost $170 to 200 $/kW, the open cycle gas turbine plant should see duty for peaking and intermediate load duty.
Economics of nuclear power and climate change mitigation policies.
Bauer, Nico; Brecha, Robert J; Luderer, Gunnar
2012-10-16
The events of March 2011 at the nuclear power complex in Fukushima, Japan, raised questions about the safe operation of nuclear power plants, with early retirement of existing nuclear power plants being debated in the policy arena and considered by regulators. Also, the future of building new nuclear power plants is highly uncertain. Should nuclear power policies become more restrictive, one potential option for climate change mitigation will be less available. However, a systematic analysis of nuclear power policies, including early retirement, has been missing in the climate change mitigation literature. We apply an energy economy model framework to derive scenarios and analyze the interactions and tradeoffs between these two policy fields. Our results indicate that early retirement of nuclear power plants leads to discounted cumulative global GDP losses of 0.07% by 2020. If, in addition, new nuclear investments are excluded, total losses will double. The effect of climate policies imposed by an intertemporal carbon budget on incremental costs of policies restricting nuclear power use is small. However, climate policies have much larger impacts than policies restricting the use of nuclear power. The carbon budget leads to cumulative discounted near term reductions of global GDP of 0.64% until 2020. Intertemporal flexibility of the carbon budget approach enables higher near-term emissions as a result of increased power generation from natural gas to fill the emerging gap in electricity supply, while still remaining within the overall carbon budget. Demand reductions and efficiency improvements are the second major response strategy.
Economics of nuclear power and climate change mitigation policies
Bauer, Nico; Brecha, Robert J.; Luderer, Gunnar
2012-01-01
The events of March 2011 at the nuclear power complex in Fukushima, Japan, raised questions about the safe operation of nuclear power plants, with early retirement of existing nuclear power plants being debated in the policy arena and considered by regulators. Also, the future of building new nuclear power plants is highly uncertain. Should nuclear power policies become more restrictive, one potential option for climate change mitigation will be less available. However, a systematic analysis of nuclear power policies, including early retirement, has been missing in the climate change mitigation literature. We apply an energy economy model framework to derive scenarios and analyze the interactions and tradeoffs between these two policy fields. Our results indicate that early retirement of nuclear power plants leads to discounted cumulative global GDP losses of 0.07% by 2020. If, in addition, new nuclear investments are excluded, total losses will double. The effect of climate policies imposed by an intertemporal carbon budget on incremental costs of policies restricting nuclear power use is small. However, climate policies have much larger impacts than policies restricting the use of nuclear power. The carbon budget leads to cumulative discounted near term reductions of global GDP of 0.64% until 2020. Intertemporal flexibility of the carbon budget approach enables higher near-term emissions as a result of increased power generation from natural gas to fill the emerging gap in electricity supply, while still remaining within the overall carbon budget. Demand reductions and efficiency improvements are the second major response strategy. PMID:23027963
AVERT Main Module Quick Start Guide
Learn how to get started with the AVERT tool, which guides non-experts in evaluating county-level emissions displaced at electric power plants by energy efficiency and renewable energy policies and programs.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lucchini, F.M.; Pezzella, B.
1998-07-01
The paper has the goal to give a general overview of the current approach for the design of modern Waste to Energy (WtE) plants. The thermal treatment of solid waste is an environmentally sound method to get rid of the garbage produced by everyone and to recover energy simultaneously. A typical waste to energy plant is divided in four segments: incineration/boiler, air pollution control, residues treatment and power generation. Still in the 80's a WtE plant was simply consisting of a these four segments without any particular effort in putting them together into a coordinated plant; therefore the results weremore » very poor in term of overall plant performances even if the single segments were properly designed. This paper shows how this approach is changing and how the synergism between the segments allows to reach interesting performances in term of electric efficiency, always keeping in mind that power must be considered a by-product of the incinerator. Therefore all these efforts have to be done without affecting the burning capacity of the station. The new Milan WtE plant is taken as example throughout the paper. The first section of the paper tries to consider the Municipal Solid Waste as standard fuel; then focal point becomes the electrical efficiency of the plant. In the fourth section the flue gas cleaning system is approached, pointing out the gas quality at stack. Then in the fifth and sixth paragraphs all most important and innovative technical solutions of the Milan plant are shown with some details on water/steam cycle, giving also some availability results. Chapter seven shows some interesting key-figures, related to the combustion of 1,000 kg of MSW at 11 MJ/kg, with also some economical evaluations in term of investment cost per ton of waste per day.« less
NASA Astrophysics Data System (ADS)
Siam, M. S.; Alqatari, S.; Ibrahim, H. D.; AlAloula, R. A.; Alrished, M.; AlSaati, A.; Eltahir, E. A. B.
2016-12-01
Increasing water demand in Saudi Arabia due to rapid population growth has forced the rapid expansion of seawater desalination plants in order to meet both current and future freshwater needs. Saudi Arabia has a huge potential for solar energy, hence, solar-powered desalination plants provide an opportunity to sustainably address the freshwater demand in the kingdom without relying on fossil fuels energy. However, the desert climate of Saudi Arabia and limited access to the open ocean imposes several challenges to the expansion and sustainability of solar-powered desalination plants. For example, the frequent and intense dust storms that occur in the region can degrade solar panels and significantly reduce their efficiency. Moreover, the high salinity Arabian Gulf is both the source of feedwater and sink of hypersaline discharge (brine) for many plants in the east of the Kingdom, and the brine may alter the salinity, temperature and movement of the water thereby reducing the quality of the feedwater to the desalination plants. Here, we propose a framework to investigate the different interactions between climate, dust, solar power generation and seawater desalination in order to identify optimal parameters such as locations of solar panels and seawater intake for sustainable implementation of solar-powered desalination plants. This framework integrates several numerical models including regional climate, hydrodynamics, Photovoltaics (PV) and Photovoltaic-Reverse Osmosis (PV-RO) models that are used to investigate these interactions for a solar-powered desalination plant at AlKhafji on the Northeastern coast of Saudi Arabia.
Nuclear power program and technology development in Korea
DOE Office of Scientific and Technical Information (OSTI.GOV)
Cho, Byung-Oke
1994-12-31
KEPCO has successfully implemented the construction and operation of nuclear power plants since the early 1970s, and will continue to build safer and more efficient nuclear plants in the future in accordance with the nuclear power development plan previously established. KEPCO will also make every effort to enhance nuclear safety and obtain the public`s acceptance for nuclear power. We are, however, facing the same difficulties, as United States and other countries have, in strengthened regulatory requirements, public acceptance, radwaste disposal, and acquisition of new plant sites despite an active nuclear power program. Story of Ted Turner, CNN; {open_quotes}It ain`t asmore » easy as it looks.{close_quotes} Yes! It is difficult. But we will cope with these issues so that we can promote the nuclear power development and continue to supply a highly economical and clean energy to the world. In this regard, it is my sincere wish that each organization participating in the nuclear industry, especially Korea and United States strengthen their ties and help each other so that we together can successfully accomplish our goals.« less
Supplier selection criteria for sustainable supply chain management in thermal power plant
NASA Astrophysics Data System (ADS)
Firoz, Faisal; Narayan Biswal, Jitendra; Satapathy, Suchismita
2018-02-01
Supplies are always in great demand when it comes to industrial operations. The quality of raw material their price accompanied by sustainability and environmental effects are a major concern for industrial operators these days. Supply Chain Management is the subject which is focused on how the supply of different products is carried out. The motive is that each operation performed can be optimized and inherently the efficiency of the whole chain is integrated. In this paper we will be dealing with all the criteria that are required to be evaluated before selecting a supplier, in particular, focusing on Thermal Power Plant. The most suppliers of the thermal power plant are the coal suppliers. The quality of coal directly determines the efficiency of the whole plant. And when there are matters concerning coal environmental pollution plays a very crucial role. ANP method has been used here to select suppliers of thermal power sectors in Indian context. After applying ANP to prioritize the sustainable supplier selection criteria, it is found that for thermal power industries best suppliers are Nationalized/State owned suppliers then 2nd ranked suppliers are imported supplier. Private owned suppliers are ranked least. So private owned suppliers must be more concerned about their performance. Among these suppliers it is found that to compete in the global market privatized suppliers have to give more emphasize on most important criteria like sustainability, then fuel cost and quality. Still some sub-criteria like a clean program, environmental issues, quality, reliability, service rate, investment in high technology, green transportation channel, waste management etc needs for continuous improvement as per their priority.
NASA Astrophysics Data System (ADS)
Reyes-Belmonte, Miguel A.; Sebastián, Andrés; González-Aguilar, José; Romero, Manuel
2017-06-01
The potential of using different thermodynamic cycles coupled to a solar tower central receiver that uses a novel heat transfer fluid is analyzed. The new fluid, named as DPS, is a dense suspension of solid particles aerated through a tubular receiver used to convert concentrated solar energy into thermal power. This novel fluid allows reaching high temperatures at the solar receiver what opens a wide range of possibilities for power cycle selection. This work has been focused into the assessment of power plant performance using conventional, but optimized cycles but also novel thermodynamic concepts. Cases studied are ranging from subcritical steam Rankine cycle; open regenerative Brayton air configurations at medium and high temperature; combined cycle; closed regenerative Brayton helium scheme and closed recompression supercritical carbon dioxide Brayton cycle. Power cycle diagrams and working conditions for design point are compared amongst the studied cases for a common reference thermal power of 57 MWth reaching the central cavity receiver. It has been found that Brayton air cycle working at high temperature or using supercritical carbon dioxide are the most promising solutions in terms of efficiency conversion for the power block of future generation by means of concentrated solar power plants.
NASA Astrophysics Data System (ADS)
Grigor'ev, S. A.; Grigor'ev, A. S.; Kuleshov, N. V.; Fateev, V. N.; Kuleshov, V. N.
2015-02-01
The layout of a combined heat and power (cogeneration) plant based on renewable energy sources (RESs) and hydrogen electrochemical systems for the accumulation of energy via the direct and inverse conversion of the electrical energy from RESs into the chemical energy of hydrogen with the storage of the latter is described. Some efficient technical solutions on the use of electrochemical hydrogen systems in power engineering for the storage of energy with a cyclic energy conversion efficiency of more than 40% are proposed. It is shown that the storage of energy in the form of hydrogen is environmentally safe and considerably surpasses traditional accumulator batteries by its capacitance characteristics, being especially topical in the prolonged absence of energy supply from RESs, e.g., under the conditions of polar night and breathless weather. To provide the required heat consumption of an object during the peak period, it is proposed to burn some hydrogen in a boiler house.
Development of heat sink concept for near-term fusion power plant divertor
NASA Astrophysics Data System (ADS)
Rimza, Sandeep; Khirwadkar, Samir; Velusamy, Karupanna
2017-04-01
Development of an efficient divertor concept is an important task to meet in the scenario of the future fusion power plant. The divertor, which is a vital part of the reactor has to discharge the considerable fraction of the total fusion thermal power (∼15%). Therefore, it has to survive very high thermal fluxes (∼10 MW/m2). In the present paper, an efficient divertor heat exchanger cooled by helium is proposed for the fusion tokamak. The Plasma facing surface of divertor made-up of several modules to overcome the stresses caused by high heat flux. The thermal hydraulic performance of one such module is numerically investigated in the present work. The result shows that the proposed design is capable of handling target heat flux values of 10 MW/m2. The computational model has been validated against high-heat flux experiments and a satisfactory agreement is noticed between the present simulation and the reported results.
NASA Astrophysics Data System (ADS)
Gabderakhmanova, T. S.; Kiseleva, S. V.; Frid, S. E.; Tarasenko, A. B.
2016-11-01
This paper is devoted to calculation of yearly energy production, demanded area and capital costs for first Russian 5 MW grid-tie photovoltaic (PV) plant in Altay Republic that is named Kosh-Agach. Simple linear calculation model, involving average solar radiation and temperature data, grid-tie inverter power-efficiency dependence and PV modules parameters is proposed. Monthly and yearly energy production, equipment costs and demanded area for PV plant are estimated for mono-, polycrystalline and amorphous modules. Calculation includes three types of initial radiation and temperature data—average day for every month from NASA SSE, average radiation and temperature for each day of the year from NASA POWER and typical meteorology year generated from average data for every month. The peculiarities for each type of initial data and their influence on results are discussed.
Erbay, Celal; Carreon-Bautista, Salvador; Sanchez-Sinencio, Edgar; Han, Arum
2014-12-02
Microbial fuel cell (MFC) that can directly generate electricity from organic waste or biomass is a promising renewable and clean technology. However, low power and low voltage output of MFCs typically do not allow directly operating most electrical applications, whether it is supplementing electricity to wastewater treatment plants or for powering autonomous wireless sensor networks. Power management systems (PMSs) can overcome this limitation by boosting the MFC output voltage and managing the power for maximum efficiency. We present a monolithic low-power-consuming PMS integrated circuit (IC) chip capable of dynamic maximum power point tracking (MPPT) to maximize the extracted power from MFCs, regardless of the power and voltage fluctuations from MFCs over time. The proposed PMS continuously detects the maximum power point (MPP) of the MFC and matches the load impedance of the PMS for maximum efficiency. The system also operates autonomously by directly drawing power from the MFC itself without any external power. The overall system efficiency, defined as the ratio between input energy from the MFC and output energy stored into the supercapacitor of the PMS, was 30%. As a demonstration, the PMS connected to a 240 mL two-chamber MFC (generating 0.4 V and 512 μW at MPP) successfully powered a wireless temperature sensor that requires a voltage of 2.5 V and consumes power of 85 mW each time it transmit the sensor data, and successfully transmitted a sensor reading every 7.5 min. The PMS also efficiently managed the power output of a lower-power producing MFC, demonstrating that the PMS works efficiently at various MFC power output level.
Gasification of agricultural residues in a demonstrative plant: corn cobs.
Biagini, Enrico; Barontini, Federica; Tognotti, Leonardo
2014-12-01
Biomass gasification couples the high power efficiency with the possibility of valuably using the byproducts heat and biochar. The use of agricultural wastes instead of woody feedstock extends the seasonal availability of biomasses. The downdraft type is the most used reactor but has narrow ranges of feedstock specifications (above all on moisture and particle size distribution), so tests on a demonstrative scale are conducted to prove the versatility of the gasifier. Measurements on pressure drops, syngas flow rate and composition are studied to assess the feasibility of such operations with corn cobs. Material and energy balances, and performance indexes are compared for the four tests carried out under different biomass loads (66-85 kg/h). A good operability of the plant and interesting results are obtained (gas specific production of 2 m3/kg, gas heating value 5.6-5.8 MJ/m3, cold gas efficiency in the range 66-68%, potential net power efficiency 21.1-21.6%). Copyright © 2014 Elsevier Ltd. All rights reserved.
Welding Metallurgy of Nickel-Based Superalloys for Power Plant Construction
NASA Astrophysics Data System (ADS)
Tung, David C.
Increasing the steam temperature and pressure in coal-fired power plants is a perpetual goal driven by the pursuit of increasing thermal cycle efficiency and reducing fuel consumption and emissions. The next target steam operating conditions, which are 760°C (1400°F) and 35 MPa (5000 psi) are known as Advanced Ultra Supercritical (AUSC), and can reduce CO2 emissions up to 13% but this cannot be achieved with traditional power plant construction materials. The use of precipitation-strengthened Nickel-based alloys (superalloys) is required for components which will experience the highest operating temperatures. The leading candidate superalloys for power plant construction are alloys 740H, 282, and 617. Superalloys have excellent elevated temperature properties due to careful microstructural design which is achieved through very specific heat treatments, often requiring solution annealing or homogenization at temperatures of 1100 °C or higher. A series of postweld heat treatments was investigated and it was found that homogenization steps before aging had no noticeable effect on weld metal microhardness, however; there were clear improvements in weld metal homogeneity. The full abstract can be viewed in the document itself.
Treatment of wastewater from flue gas desulphurization plants in the Netherlands
DOE Office of Scientific and Technical Information (OSTI.GOV)
Vredenbregt, L.H.J.; Brugghen, F.W. van der; Enoch, G.D.
1995-06-01
In the Netherlands, all coal fired boilers of power stations are equipped with a wet lime(stone)-gypsum flue gas desulphurization (FGD) installation in order to fulfill the emission demands for SO{sub 2}. These wet FGD installations produce a wastewater stream containing impurities like suspended solids and traces of heavy metals like As, Cd, Cr, Cu, Hg, Ni, Pb, Sb, Se and Za. As the target values stated by the licensing authorities are very stringent, most of these heavy metals and suspended solids have to be removed to very low concentration levels. Therefore, a very efficient treatment method, based on coprecipitation ofmore » heavy metal hydroxides and sulphides, which was developed by KEMA, has been installed at all, the coal fired power plants. This paper describes the operational experiences until now with these wastewater treatment installations at two coal fired power plants using sea-water for make-up and one using fresh water. The following aspects will be discussed in more detail: reliability of the wastewater treatment processes both with respect to removal efficiency of heavy metals and suspended solids and plant operation itself influence of a changing composition of the wastewater on the performance of these wastewater treatment installations. Finally, also the impact of co-firing of the sludge produced in these wastewater treatment installations will be discussed.« less
Kim, Byeong-Uk; Kim, Okgil; Kim, Hyun Cheol; Kim, Soontae
2016-09-01
The South Korean government plans to reduce region-wide annual PM2.5 (particulate matter with an aerodynamic diameter ≤2.5 μm) concentrations in the Seoul Capital Area (SCA) from 2010 levels of 27 µg/m(3) to 20 µg/m(3) by 2024. At the same time, it is inevitable that emissions from fossil-fuel power plants will continue to increase if electricity generation expands and the generation portfolio remains the same in the future. To estimate incremental PM2.5 contributions due to projected electricity generation growth in South Korea, we utilized an ensemble forecasting member of the Integrated Multidimensional Air Quality System for Korea based on the Community Multi-scale Air Quality model. We performed sensitivity runs with across-the-board emission reductions for all fossil-fuel power plants in South Korea to estimate the contribution of PM2.5 from domestic fossil-fuel power plants. We estimated that fossil-fuel power plants are responsible for 2.4% of the annual PM2.5 national ambient air quality standard in the SCA as of 2010. Based on the electricity generation and the annual contribution of fossil-fuel power plants in 2010, we estimated that annual PM2.5 concentrations may increase by 0.2 µg/m(3) per 100 TWhr due to additional electricity generation. With currently available information on future electricity demands, we estimated that the total future contribution of fossil-fuel power plants would be 0.87 µg/m(3), which is 12.4% of the target reduction amount of the annual PM2.5 concentration by 2024. We also approximated that the number of premature deaths caused by existing fossil-fuel power plants would be 736 in 2024. Since the proximity of power plants to the SCA and the types of fuel used significantly impact this estimation, further studies are warranted on the impact of physical parameters of plants, such as location and stack height, on PM2.5 concentrations in the SCA due to each precursor. Improving air quality by reducing fine particle pollution is challenging when fossil-fuel-based electricity production is increasing. We show that an air quality forecasting system based on a photochemical model can be utilized to efficiently estimate PM2.5 contributions from and health impacts of domestic power plants. We derived PM2.5 concentrations per unit amount of electricity production from existing fossil-fuel power plants in South Korea. We assessed the health impacts of existing fossil-fuel power plants and the PM2.5 concentrations per unit electricity production to quantify the significance of existing and future fossil-fuel power plants with respect to the planned PM2.5 reduction target.
Pyroelectric Energy Scavenging Techniques for Self-Powered Nuclear Reactor Wireless Sensor Networks
Hunter, Scott Robert; Lavrik, Nickolay V; Datskos, Panos G; ...
2014-11-01
Recent advances in technologies for harvesting waste thermal energy from ambient environments present an opportunity to implement truly wireless sensor nodes in nuclear power plants. These sensors could continue to operate during extended station blackouts and during periods when operation of the plant s internal power distribution system has been disrupted. The energy required to power the wireless sensors must be generated using energy harvesting techniques from locally available energy sources, and the energy consumption within the sensor circuitry must therefore be low to minimize power and hence the size requirements of the energy harvester. Harvesting electrical energy from thermalmore » energy sources can be achieved using pyroelectric or thermoelectric conversion techniques. Recent modeling and experimental studies have shown that pyroelectric techniques can be cost competitive with thermoelectrics in self powered wireless sensor applications and, using new temperature cycling techniques, has the potential to be several times as efficient as thermoelectrics under comparable operating conditions. The development of a new thermal energy harvester concept, based on temperature cycled pyroelectric thermal-to-electrical energy conversion, is outlined. This paper outlines the modeling of cantilever and pyroelectric structures and single element devices that demonstrate the potential of this technology for the development of high efficiency thermal-to-electrical energy conversion devices.« less
Pyroelectric Energy Scavenging Techniques for Self-Powered Nuclear Reactor Wireless Sensor Networks
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hunter, Scott Robert; Lavrik, Nickolay V; Datskos, Panos G
Recent advances in technologies for harvesting waste thermal energy from ambient environments present an opportunity to implement truly wireless sensor nodes in nuclear power plants. These sensors could continue to operate during extended station blackouts and during periods when operation of the plant s internal power distribution system has been disrupted. The energy required to power the wireless sensors must be generated using energy harvesting techniques from locally available energy sources, and the energy consumption within the sensor circuitry must therefore be low to minimize power and hence the size requirements of the energy harvester. Harvesting electrical energy from thermalmore » energy sources can be achieved using pyroelectric or thermoelectric conversion techniques. Recent modeling and experimental studies have shown that pyroelectric techniques can be cost competitive with thermoelectrics in self powered wireless sensor applications and, using new temperature cycling techniques, has the potential to be several times as efficient as thermoelectrics under comparable operating conditions. The development of a new thermal energy harvester concept, based on temperature cycled pyroelectric thermal-to-electrical energy conversion, is outlined. This paper outlines the modeling of cantilever and pyroelectric structures and single element devices that demonstrate the potential of this technology for the development of high efficiency thermal-to-electrical energy conversion devices.« less
NASA Astrophysics Data System (ADS)
Ho, S. Ping; Hsu, Yaowen
2015-04-01
In order to meet the requirements of the rapid economic growth, many countries demand an increasing number of power plants to meet the increasing electricity usage. Since high capital requirements of power plants present a big issue for these countries, PPPs have been considered an alternative to provide power plant infrastructure. In particular, in emerging or developing countries, PPPs may be the fastest way to provide the infrastructure needed. However, while PPPs are a promising alternative to providing various types of infrastructure, many failed power plant PPP projects have made it evident that PPPs, under certain situations, can be very costly or even a wrong choice of governance structure. While the higher efficiency due to better pooling of resources is greatly emphasized in Public-Private Partnerships (PPPs), the embedded transaction inefficiencies are often understated or even ignored. Through the lens of Transaction Cost Economics (TCE), this paper aims to answer why and when PPPs may become a costly governance structure for power plants. Specifically, we develop a TCE-based theory of PPPs as a governance structure. This theory suggests that three major opportunism problems embedded in infrastructure PPPs are possible to cause substantial transaction costs and render PPPs a costly governance structure. The three main opportunism problems are principal-principal problem, firm's hold-up problem, and government-led hold-up problem. Moreover, project and institutional characteristics that may lead to opportunism problems are identified. Based on these characteristics, an opportunism-focused transaction cost analysis (OTCA) for PPPs as a governance structure is proposed to supplement the current practice of PPP feasibility analysis. As a part of theory development, a case study of PPP power plants is performed to evaluate the proposed theory and to illustrate how the proposed OTCA can be applied in practice. Policies and administration strategies for power plant PPPs are derived based on the proposed theory.
Chiller plant design rules...Have they changed?
DOE Office of Scientific and Technical Information (OSTI.GOV)
Eppelheimer, D.
1995-09-01
Chilled water plants are often viewed as energy consumers, actually they are only energy movers. In just the simple process of chilling water, there are four discrete energy moving functions. The chilled water pumps, condenser water pumps, and cooling tower fans are all forms of transport energy. The chiller is a heat pump where energy is consumed to raise the temperature of the heat stream. Insight into improved chiller plant performance can be obtained by tracking the power consumption of these four functions. The performance of centrifugal chillers has improved dramatically in the past 25 years. Certainly some of thismore » improvement is due to technology improvements in heat transfer and compressor efficiency. However, the lion`s share of gain in chiller efficiency is a result of chiller owners budgeting more funds to energy conservation and purchasing more efficient chillers. Since 1970, the efficiency of electric water chillers has improved by nearly 4 percent! The intent of this presentation is to review the energy cost associated with central chilled water plants and identify opportunities in design that may reduce energy costs.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Harrison, T. J.
2014-02-01
The cost of nuclear power is a straightforward yet complicated topic. It is straightforward in that the cost of nuclear power is a function of the cost to build the nuclear power plant, the cost to operate and maintain it, and the cost to provide fuel for it. It is complicated in that some of those costs are not necessarily known, introducing uncertainty into the analysis. For large light water reactor (LWR)-based nuclear power plants, the uncertainty is mainly contained within the cost of construction. The typical costs of operations and maintenance (O&M), as well as fuel, are well knownmore » based on the current fleet of LWRs. However, the last currently operating reactor to come online was Watts Bar 1 in May 1996; thus, the expected construction costs for gigawatt (GW)-class reactors in the United States are based on information nearly two decades old. Extrapolating construction, O&M, and fuel costs from GW-class LWRs to LWR-based small modular reactors (SMRs) introduces even more complication. The per-installed-kilowatt construction costs for SMRs are likely to be higher than those for the GW-class reactors based on the property of the economy of scale. Generally speaking, the economy of scale is the tendency for overall costs to increase slower than the overall production capacity. For power plants, this means that doubling the power production capacity would be expected to cost less than twice as much. Applying this property in the opposite direction, halving the power production capacity would be expected to cost more than half as much. This can potentially make the SMRs less competitive in the electricity market against the GW-class reactors, as well as against other power sources such as natural gas and subsidized renewables. One factor that can potentially aid the SMRs in achieving economic competitiveness is an economy of numbers, as opposed to the economy of scale, associated with learning curves. The basic concept of the learning curve is that the more a new process is repeated, the more efficient the process can be made. Assuming that efficiency directly relates to cost means that the more a new process is repeated successfully and efficiently, the less costly the process can be made. This factor ties directly into the factory fabrication and modularization aspect of the SMR paradigm—manufacturing serial, standardized, identical components for use in nuclear power plants can allow the SMR industry to use the learning curves to predict and optimize deployment costs.« less
Theoretical Investigation For The Effect of Fuel Quality on Gas Turbine Power Plants
NASA Astrophysics Data System (ADS)
AbdulRazzak khudair, Omar; Alwan Abass, Khetam; Saadi Abed, Noor; Hussain Ali, Khalid; AbdulAziz, Saad; Chlaib Shaboot, Ali
2018-05-01
Gas turbine engine power generation is declined dramatically because of the reduction in thermodynamic parameters as a work of turbine, compressor ratio, compressor work, and air mass flow rate and fuel consumption. There are two main objectives of this work, the first is related with the effect of fuel kinds and their quality on the operation of fuel flow divider and its performance specifically gear pump displacement and fuel flow rate to the combustion chambers of gas power plant. AL-DORA gas turbine power plant 35MW was chosen to predict these effects on its performance MATLAB Software program is used to perform thermodynamic calculations. Fuel distribution stage before the process of combustion and as a result of the kind and its quality, chemical reaction will occur between the fuel and the parts of the gear system of each pump of the flow divider, which causes the erosion of the internal pump wall and the teeth of the gear system, thus hampering the pump operation in terms of fuel discharge. The discharge of fuel form the eight external gates of flow divider is decreased and varied when going to the combustion chambers, so that, flow divider does not give reliable mass flow rate due to absence of accurate pressure in each of eight exit pipes. The second objective deals with the stage of fuel combustion process inside the combustion chamber. A comparative study based upon performance parameters, such as specific fuel consumption for gas and gasoil and power generation. Fuel poor quality causes incomplete combustion and increased its consumption, so that combustion products are interacted with the surface of the turbine blades, causing the erosion and create surface roughness of the blade and disruption of gas flow. As a result of this situation, turbulence flow of these gases will increase causing the separation of gas boundary layers over the suction surface of the blade. Therefore the amount of extracted gas will decrease causing retreat work done by turbine, as a result decline of power and gas turbine power plant efficiency causing the drop in the level of electric generation. The fuel quality is found to be a strong function of specific fuel consumption and its effects on the power generation and the efficiency of the gas turbine power plants and hence, the cycle performance shifts towards favorable conditions.
NASA Astrophysics Data System (ADS)
1985-12-01
Topics related to aerospace power are discussed, taking into account trends and issues of military space power systems technology, space station power system advanced development, the application and use of nuclear power for future spacecraft, the current status of advanced solar array technology development, the application of a parabolic trough concentrator to space station power needs, life test results of the Intelsat-V nickel-cadmium battery, and metal hydride hydrogen storage in nickel hydrogen batteries. Other subjects explored are concerned with alternative fuels, biomass energy, biomedical power, coal gasification, electric power cycles, and electric propulsion. Attention is given to an advanced terrestrial vehicle electric propulsion systems assessment, fuel cells as electric propulsion power plants, a sinewave synthesis for high efficiency dc-ac conversion, steam desulfurization of coal, leadless transfer of energy into the body to power implanted blood pumps, oil production via entrained flow pyrolysis of biomass, and a New Zealand synthetic gasoline plant.
Thermal pollution impacts on rivers and power supply in the Mississippi River watershed
DOE Office of Scientific and Technical Information (OSTI.GOV)
Miara, Ariel; Vorosmarty, Charles J.; Macknick, Jordan E.
Thermal pollution from power plants degrades riverine ecosystems with ramifications beyond the natural environment as it affects power supply. The transport of thermal effluents along river reaches may lead to plant-to-plant interferences by elevating condenser inlet temperatures at downstream locations, which lower thermal efficiencies and trigger regulatory-forced power curtailments. We evaluate thermal pollution impacts on rivers and power supply across 128 plants with once-through cooling technologies in the Mississippi River watershed. By leveraging river network topologies with higher resolutions (0.05 degrees) than previous studies, we reveal the need to address the issue in a more spatially resolved manner, capable ofmore » uncovering diverse impacts across individual plants, river reaches and sub-basins. Results show that the use of coarse river network resolutions may lead to substantial overestimations in magnitude and length of impaired river reaches. Overall, there is a modest limitation on power production due to thermal pollution, given existing infrastructure, regulatory and climate conditions. However, tradeoffs between thermal pollution and electricity generation show important implications for the role of alternative cooling technologies and environmental regulation under current and future climates. Recirculating cooling technologies may nearly eliminate thermal pollution and improve power system reliability under stressed climate-water conditions. Regulatory limits also reduce thermal pollution, but at the expense of significant reductions in electricity generation capacity. However, results show several instances when power production capacity rises at individual plants when regulatory limits reduce upstream thermal pollution. Furthermore, these dynamics across energy-water systems highlight the need for high-resolution simulations and the value of coherent planning and optimization across infrastructure with mutual dependencies on natural resources to overcome climate-water constraints on productivity and bring to fruition energy and environmental win-win opportunities.« less
Thermal pollution impacts on rivers and power supply in the Mississippi River watershed
Miara, Ariel; Vorosmarty, Charles J.; Macknick, Jordan E.; ...
2018-03-08
Thermal pollution from power plants degrades riverine ecosystems with ramifications beyond the natural environment as it affects power supply. The transport of thermal effluents along river reaches may lead to plant-to-plant interferences by elevating condenser inlet temperatures at downstream locations, which lower thermal efficiencies and trigger regulatory-forced power curtailments. We evaluate thermal pollution impacts on rivers and power supply across 128 plants with once-through cooling technologies in the Mississippi River watershed. By leveraging river network topologies with higher resolutions (0.05 degrees) than previous studies, we reveal the need to address the issue in a more spatially resolved manner, capable ofmore » uncovering diverse impacts across individual plants, river reaches and sub-basins. Results show that the use of coarse river network resolutions may lead to substantial overestimations in magnitude and length of impaired river reaches. Overall, there is a modest limitation on power production due to thermal pollution, given existing infrastructure, regulatory and climate conditions. However, tradeoffs between thermal pollution and electricity generation show important implications for the role of alternative cooling technologies and environmental regulation under current and future climates. Recirculating cooling technologies may nearly eliminate thermal pollution and improve power system reliability under stressed climate-water conditions. Regulatory limits also reduce thermal pollution, but at the expense of significant reductions in electricity generation capacity. However, results show several instances when power production capacity rises at individual plants when regulatory limits reduce upstream thermal pollution. Furthermore, these dynamics across energy-water systems highlight the need for high-resolution simulations and the value of coherent planning and optimization across infrastructure with mutual dependencies on natural resources to overcome climate-water constraints on productivity and bring to fruition energy and environmental win-win opportunities.« less
Thermal pollution impacts on rivers and power supply in the Mississippi River watershed
NASA Astrophysics Data System (ADS)
Miara, Ariel; Vörösmarty, Charles J.; Macknick, Jordan E.; Tidwell, Vincent C.; Fekete, Balazs; Corsi, Fabio; Newmark, Robin
2018-03-01
Thermal pollution from power plants degrades riverine ecosystems with ramifications beyond the natural environment as it affects power supply. The transport of thermal effluents along river reaches may lead to plant-to-plant interferences by elevating condenser inlet temperatures at downstream locations, which lower thermal efficiencies and trigger regulatory-forced power curtailments. We evaluate thermal pollution impacts on rivers and power supply across 128 plants with once-through cooling technologies in the Mississippi River watershed. By leveraging river network topologies with higher resolutions (0.05°) than previous studies, we reveal the need to address the issue in a more spatially resolved manner, capable of uncovering diverse impacts across individual plants, river reaches and sub-basins. Results show that the use of coarse river network resolutions may lead to substantial overestimations in magnitude and length of impaired river reaches. Overall, there is a modest limitation on power production due to thermal pollution, given existing infrastructure, regulatory and climate conditions. However, tradeoffs between thermal pollution and electricity generation show important implications for the role of alternative cooling technologies and environmental regulation under current and future climates. Recirculating cooling technologies may nearly eliminate thermal pollution and improve power system reliability under stressed climate-water conditions. Regulatory limits also reduce thermal pollution, but at the expense of significant reductions in electricity generation capacity. However, results show several instances when power production capacity rises at individual plants when regulatory limits reduce upstream thermal pollution. These dynamics across energy-water systems highlight the need for high-resolution simulations and the value of coherent planning and optimization across infrastructure with mutual dependencies on natural resources to overcome climate-water constraints on productivity and bring to fruition energy and environmental win-win opportunities.
Long-Term Heating to Improve Receiver Performance
DOE Office of Scientific and Technical Information (OSTI.GOV)
Glatzmaier, Greg C.; Cable, Robert; Newmarker, Marc
The buildup of hydrogen in the heat transfer fluid (HTF) that circulates through components of parabolic trough power plants decreases receiver thermal efficiency, and ultimately, it decreases plant performance and electricity output. The generation and occurrence of hydrogen in the HTF provides the driving force for hydrogen to permeate from the HTF through the absorber tube wall and into the receiver annulus. Getters adsorb hydrogen from the annulus volume until they saturate and are no longer able to maintain low hydrogen pressure. The increase in hydrogen pressure within the annulus significantly degrades thermal performance of the receiver and decreases overallmore » power-plant efficiency. NREL and Acciona Energy North America (Acciona) are developing a method to control the levels of dissolved hydrogen in the circulating HTF. The basic approach is to remove hydrogen from the expansion tanks of the HTF subsystem at a rate that maintains hydrogen in the circulating HTF to a target level. Full-plant steady-state models developed by the National Renewable Energy Laboratory (NREL) predict that if hydrogen is removed from the HTF within the expansion tanks, the HTF that circulates through the collector field remains essentially free of hydrogen until the HTF returns to the power block in the hot headers. One of the key findings of our modeling is the prediction that hydrogen will reverse-permeate out of the receiver annulus if dissolved hydrogen in the HTF is kept sufficiently low. To test this prediction, we performed extended heating of an in-service receiver that initially had high levels of hydrogen in its annulus. The heating was performed using NREL's receiver test stand. Results of our testing showed that receiver heat loss steadily decreased with daily heating, resulting in a corresponding improvement in receiver thermal efficiency.« less
NASA Astrophysics Data System (ADS)
Douvartzides, S.; Karmalis, I.
2016-11-01
A detailed method is presented on the thermal design of a natural gas - diesel dual fuel internal combustion engine. An 18 cylinder four stroke turbocharged engine is considered to operate at a maximum speed of 500 rpm for marine and power plant applications. Thermodynamic, heat transfer and fluid flow phenomena are mathematically analyzed to provide a real cycle analysis together with a complete set of calculated operation conditions, power characteristics and engine efficiencies. The method is found to provide results in close agreement to published data for the actual performance of similar engines such as V18 MAN 51/60DF.
In Hot Water: A Cooling Tower Case Study. Instructor's Manual
ERIC Educational Resources Information Center
Cochran, Justin; Raju, P. K.; Sankar, Chetan
2005-01-01
Vogtle Electric Generating Plant operated by Southern Nuclear Operating Company, a subsidiary of Southern Company, has found itself at a decision point. Vogtle depends on their natural draft cooling towers to remove heat from the power cycle. Depending on the efficiency of the towers, the cycle can realize more or less power output. The efficiency…
Electricity's Future: The Shift to Efficiency and Small-Scale Power. Worldwatch Paper 61.
ERIC Educational Resources Information Center
Flavin, Christopher
Electricity, which has largely supplanted oil as the most controversial energy issue of the 1980s, is at the center of some of the world's bitterest economic and environmental controversies. Soaring costs, high interest rates, and environmental damage caused by large power plants have wreaked havoc on the once booming electricity industry.…
Power and Leader Effectiveness in Organizations: A Literature Review
2008-09-01
cinema and television as dramatic, memorable verbal reprimands for poor performance or an unaccomplished mission. However, coercive power does not...character played by Michael Keaton improved American automotive plant efficiency by improving working relations between the Japanese management and...attraction between the Japanese management and the American laborers. The relational benefits translated into happier employees that were more
High Efficiency and Low Cost Thermal Energy Storage System
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sienicki, James J.; Lv, Qiuping; Moisseytsev, Anton
BgtL, LLC (BgtL) is focused on developing and commercializing its proprietary compact technology for processes in the energy sector. One such application is a compact high efficiency Thermal Energy Storage (TES) system that utilizes the heat of fusion through phase change between solid and liquid to store and release energy at high temperatures and incorporate state-of-the-art insulation to minimize heat dissipation. BgtL’s TES system would greatly improve the economics of existing nuclear and coal-fired power plants by allowing the power plant to store energy when power prices are low and sell power into the grid when prices are high. Comparedmore » to existing battery storage technology, BgtL’s novel thermal energy storage solution can be significantly less costly to acquire and maintain, does not have any waste or environmental emissions, and does not deteriorate over time; it can keep constant efficiency and operates cleanly and safely. BgtL’s engineers are experienced in this field and are able to design and engineer such a system to a specific power plant’s requirements. BgtL also has a strong manufacturing partner to fabricate the system such that it qualifies for an ASME code stamp. BgtL’s vision is to be the leading provider of compact systems for various applications including energy storage. BgtL requests that all technical information about the TES designs be protected as proprietary information. To honor that request, only non-proprietay summaries are included in this report.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zhang, Yanliang; Butt, Darryl; Agarwal, Vivek
2015-07-01
The objective of this Nuclear Energy Enabling Technology research project is to develop high-efficiency and reliable thermoelectric generators for self-powered wireless sensors nodes utilizing thermal energy from nuclear plant or fuel cycle. The power harvesting technology has crosscutting significance to address critical technology gaps in monitoring nuclear plants and fuel cycle. The outcomes of the project will lead to significant advancement in sensors and instrumentation technology, reducing cost, improving monitoring reliability and therefore enhancing safety. The self-powered wireless sensor networks could support the long-term safe and economical operation of all the reactor designs and fuel cycle concepts, as well asmore » spent fuel storage and many other nuclear science and engineering applications. The research is based on recent breakthroughs in high-performance nanostructured bulk (nanobulk) thermoelectric materials that enable high-efficiency direct heat-to-electricity conversion over a wide temperature range. The nanobulk thermoelectric materials that the research team at Boise State University and University of Houston has developed yield up to a 50% increase in the thermoelectric figure of merit, ZT, compared with state-of-the-art bulk counterparts. This report focuses on the selection of optimal thermoelectric materials for this project. The team has performed extensive study on two thermoelectric materials systems, i.e. the half-Heusler materials, and the Bismuth-Telluride materials. The report contains our recent research results on the fabrication, characterization and thermoelectric property measurements of these two materials.« less
Static Converter for High Energy Utilization, Modular, Small Nuclear Power Plants
DOE Office of Scientific and Technical Information (OSTI.GOV)
El-Genk, Mohamed S.; Tournier, Jean-Michel P.
2002-07-01
This paper presents and analyzes the performance of high efficiency, high total energy utilization, static converters, which could be used in conjunction with small nuclear reactor plants in remote locations and in undersea applications, requiring little or no maintenance. The converters consist of a top cycle of Alkali Metal Thermal-to-Electric Conversion (AMTEC) units and PbTe thermoelectric (TE) bottom cycle. In addition to converting the reactor thermal power to electricity at 1150 K or less, at a thermodynamic efficiency in the low to mid thirties, the heat rejection from the TE bottom cycle could be used for space heating, industrial processing,more » or sea water desalination. The results indicated that for space heating applications, where the rejected thermal power from the TE bottom cycle is removed by natural convection of ambient air, a total utilization of the reactor thermal power of > 80% is possible. When operated at 1030 K, potassium AMTEC/TE converters are not only more efficient than the sodium AMTEC/TE converters but produce more electrical power. The present analysis showed that a single converter could be sized to produce up to 100 kWe and 70 kWe, for the Na-AMTEC/TE units when operating at 1150 K and the K-AMTEC/TE units when operating at 1030 K, respectively. Such modularity is an added advantage to the high-energy utilization of the present AMTEC/TE converters. (authors)« less
Optimization of the oxidant supply system for combined cycle MHD power plants
NASA Technical Reports Server (NTRS)
Juhasz, A. J.
1982-01-01
An in-depth study was conducted to determine what, if any, improvements could be made on the oxidant supply system for combined cycle MHD power plants which could be reflected in higher thermal efficiency and a reduction in the cost of electricity, COE. A systematic analysis of air separation process varitions which showed that the specific energy consumption could be minimized when the product stream oxygen concentration is about 70 mole percent was conducted. The use of advanced air compressors, having variable speed and guide vane position control, results in additional power savings. The study also led to the conceptual design of a new air separation process, sized for a 500 MW sub e MHD plant, referred to a internal compression is discussed. In addition to its lower overall energy consumption, potential capital cost savings were identified for air separation plants using this process when constructed in a single large air separation train rather than multiple parallel trains, typical of conventional practice.
A role for high frequency superconducting devices in free space power transmission systems
NASA Technical Reports Server (NTRS)
Christian, Jose L., Jr.; Cull, Ronald C.
1988-01-01
Major advances in space power technology are being made in photovoltaic, solar thermal, and nuclear systems. Despite these advances, the power systems required by the energy and power intensive mission of the future will be massive due to the large collecting surfaces, large thermal management systems, and heavy shielding. Reducing this mass on board the space vehicle can result in significant benefits because of the high cost of transporting and moving mass about in space. An approach to this problem is beaming the power from a point where the massiveness of the power plant is not such a major concern. The viability of such an approach was already investigated. Efficient microwave power beam transmission at 2.45 GHz was demonstrated over short range. Higher frequencies are desired for efficient transmission over several hundred or thousand kilometers in space. Superconducting DC-RF conversion as well as RF-DC conversion offers exciting possibilities. Multivoltage power conditioning for multicavity high power RF tubes could be eliminated since only low voltages are required for Josephson junctions. Small, high efficiency receivers may be possible using the reverse Josephson effects. A conceptual receiving antenna design using superconducting devices to determine possible system operating efficiency is assessed. If realized, these preliminary assessments indicate a role for superconducting devices in millimeter and submillimeter free space power transmission systems.
Heritability of targeted gene modifications induced by plant-optimized CRISPR systems.
Mao, Yanfei; Botella, Jose Ramon; Zhu, Jian-Kang
2017-03-01
The Streptococcus-derived CRISPR (Clustered Regularly Interspaced Short Palindromic Repeats)/Cas9 (CRISPR-associated protein 9) system has emerged as a very powerful tool for targeted gene modifications in many living organisms including plants. Since the first application of this system for plant gene modification in 2013, this RNA-guided DNA endonuclease system has been extensively engineered to meet the requirements of functional genomics and crop trait improvement in a number of plant species. Given its short history, the emphasis of many studies has been the optimization of the technology to improve its reliability and efficiency to generate heritable gene modifications in plants. Here we review and analyze the features of customized CRISPR/Cas9 systems developed for plant genetic studies and crop breeding. We focus on two essential aspects: the heritability of gene modifications induced by CRISPR/Cas9 and the factors affecting its efficiency, and we provide strategies for future design of systems with improved activity and heritability in plants.
Transfer of control system interface solutions from other domains to the thermal power industry.
Bligård, L-O; Andersson, J; Osvalder, A-L
2012-01-01
In a thermal power plant the operators' roles are to control and monitor the process to achieve efficient and safe production. To achieve this, the human-machine interfaces have a central part. The interfaces need to be updated and upgraded together with the technical functionality to maintain optimal operation. One way of achieving relevant updates is to study other domains and see how they have solved similar issues in their design solutions. The purpose of this paper is to present how interface design solution ideas can be transferred from domains with operator control to thermal power plants. In the study 15 domains were compared using a model for categorisation of human-machine systems. The result from the domain comparison showed that nuclear power, refinery and ship engine control were most similar to thermal power control. From the findings a basic interface structure and three specific display solutions were proposed for thermal power control: process parameter overview, plant overview, and feed water view. The systematic comparison of the properties of a human-machine system allowed interface designers to find suitable objects, structures and navigation logics in a range of domains that could be transferred to the thermal power domain.
Plant-pathogen interactions: toward development of next-generation disease-resistant plants.
Nejat, Naghmeh; Rookes, James; Mantri, Nitin L; Cahill, David M
2017-03-01
Briskly evolving phytopathogens are dire threats to our food supplies and threaten global food security. From the recent advances made toward high-throughput sequencing technologies, understanding of pathogenesis and effector biology, and plant innate immunity, translation of these means into new control tools is being introduced to develop durable disease resistance. Effectoromics as a powerful genetic tool for uncovering effector-target genes, both susceptibility genes and executor resistance genes in effector-assisted breeding, open up new avenues to improve resistance. TALENs (Transcription Activator-Like Effector Nucleases), engineered nucleases and CRISPR (Clustered Regulatory Interspaced Short Palindromic Repeats)/Cas9 systems are breakthrough and powerful techniques for genome editing, providing efficient mechanisms for targeted crop protection strategies in disease resistance programs. In this review, major advances in plant disease management to confer durable disease resistance and novel strategies for boosting plant innate immunity are highlighted.
NASA Astrophysics Data System (ADS)
Schwaiger, Karl; Haider, Markus; Haemmerle, Martin; Steiner, Peter; Obermaier, Michael-Dario
2016-05-01
Flexible dispatch able solar thermal electricity plants applying state of the art power cycles have the potential of playing a vital role in modern electricity systems and even participating in the ancillary market. By replacing molten salt via particles, operation temperatures can be increased and plant efficiencies of over 45 % can be reached. In this work the concept for a utility scale plant using corundum as storage/heat transfer material is thermodynamically modeled and its key performance data are cited. A novel indirect fluidized bed particle receiver concept is presented, profiting from a near black body behavior being able to heat up large particle flows by realizing temperature cycles over 500°C. Specialized fluidized bed steam-generators are applied with negligible auxiliary power demand. The performance of the key components is discussed and a rough sketch of the plant is provided.
Secondary Heat Exchanger Design and Comparison for Advanced High Temperature Reactor
DOE Office of Scientific and Technical Information (OSTI.GOV)
Piyush Sabharwall; Ali Siahpush; Michael McKellar
2012-06-01
The goals of next generation nuclear reactors, such as the high temperature gas-cooled reactor and advance high temperature reactor (AHTR), are to increase energy efficiency in the production of electricity and provide high temperature heat for industrial processes. The efficient transfer of energy for industrial applications depends on the ability to incorporate effective heat exchangers between the nuclear heat transport system and the industrial process heat transport system. The need for efficiency, compactness, and safety challenge the boundaries of existing heat exchanger technology, giving rise to the following study. Various studies have been performed in attempts to update the secondarymore » heat exchanger that is downstream of the primary heat exchanger, mostly because its performance is strongly tied to the ability to employ more efficient conversion cycles, such as the Rankine super critical and subcritical cycles. This study considers two different types of heat exchangers—helical coiled heat exchanger and printed circuit heat exchanger—as possible options for the AHTR secondary heat exchangers with the following three different options: (1) A single heat exchanger transfers all the heat (3,400 MW(t)) from the intermediate heat transfer loop to the power conversion system or process plants; (2) Two heat exchangers share heat to transfer total heat of 3,400 MW(t) from the intermediate heat transfer loop to the power conversion system or process plants, each exchanger transfers 1,700 MW(t) with a parallel configuration; and (3) Three heat exchangers share heat to transfer total heat of 3,400 MW(t) from the intermediate heat transfer loop to the power conversion system or process plants. Each heat exchanger transfers 1,130 MW(t) with a parallel configuration. A preliminary cost comparison will be provided for all different cases along with challenges and recommendations.« less
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.
Electric utility of the year for 1984: Potomac Electric Power
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
1984-11-01
High performance, efficiency improvements, a modest construction program, a clear balance sheet, and an effort to expend power plant life were among the qualities that earned Potomac Electric Power (PEPCO) the title of 1984 Utility of the Year. Other key elements in the utility's selection were its strategy for purchasing power, a load management plan, diversified investments into subsidiary businesses, community concern that considers the aesthetics of transmission facilities, and its interest in personnel development, especially among minorities. 3 figures.
Solar power satellite status report
NASA Technical Reports Server (NTRS)
Davis, H. P.
1977-01-01
The development of a solar power satellite program is considered. It is suggested that the solar power satellite is an engineering rather than a science program - that is, that no scientific breakthroughs are required before initiating the project. Available technology is examined, and several key questions are discussed: how efficient is microwave transfer of energy; how feasible is construction in space; and will the advantages of continuous insolation compensate for the costs of building a solar power plant in synchronous orbit 23,000 miles above the earth.
Fractal structures and fractal functions as disease indicators
Escos, J.M; Alados, C.L.; Emlen, J.M.
1995-01-01
Developmental instability is an early indicator of stress, and has been used to monitor the impacts of human disturbance on natural ecosystems. Here we investigate the use of different measures of developmental instability on two species, green peppers (Capsicum annuum), a plant, and Spanish ibex (Capra pyrenaica), an animal. For green peppers we compared the variance in allometric relationship between control plants, and a treatment group infected with the tomato spotted wilt virus. The results show that infected plants have a greater variance about the allometric regression line than the control plants. We also observed a reduction in complexity of branch structure in green pepper with a viral infection. Box-counting fractal dimension of branch architecture declined under stress infection. We also tested the reduction in complexity of behavioral patterns under stress situations in Spanish ibex (Capra pyrenaica). Fractal dimension of head-lift frequency distribution measures predator detection efficiency. This dimension decreased under stressful conditions, such as advanced pregnancy and parasitic infection. Feeding distribution activities reflect food searching efficiency. Power spectral analysis proves to be the most powerful tool for character- izing fractal behavior, revealing a reduction in complexity of time distribution activity under parasitic infection.
Analytical modeling of helium turbomachinery using FORTRAN 77
NASA Astrophysics Data System (ADS)
Balaji, Purushotham
Advanced Generation IV modular reactors, including Very High Temperature Reactors (VHTRs), utilize helium as the working fluid, with a potential for high efficiency power production utilizing helium turbomachinery. Helium is chemically inert and nonradioactive which makes the gas ideal for a nuclear power-plant environment where radioactive leaks are a high concern. These properties of helium gas helps to increase the safety features as well as to decrease the aging process of plant components. The lack of sufficient helium turbomachinery data has made it difficult to study the vital role played by the gas turbine components of these VHTR powered cycles. Therefore, this research work focuses on predicting the performance of helium compressors. A FORTRAN77 program is developed to simulate helium compressor operation, including surge line prediction. The resulting design point and off design performance data can be used to develop compressor map files readable by Numerical Propulsion Simulation Software (NPSS). This multi-physics simulation software that was developed for propulsion system analysis has found applications in simulating power-plant cycles.
Makita, Yuko; Kobayashi, Norio; Mochizuki, Yoshiki; Yoshida, Yuko; Asano, Satomi; Heida, Naohiko; Deshpande, Mrinalini; Bhatia, Rinki; Matsushima, Akihiro; Ishii, Manabu; Kawaguchi, Shuji; Iida, Kei; Hanada, Kosuke; Kuromori, Takashi; Seki, Motoaki; Shinozaki, Kazuo; Toyoda, Tetsuro
2009-07-01
Molecular breeding of crops is an efficient way to upgrade plant functions useful to mankind. A key step is forward genetics or positional cloning to identify the genes that confer useful functions. In order to accelerate the whole research process, we have developed an integrated database system powered by an intelligent data-retrieval engine termed PosMed-plus (Positional Medline for plant upgrading science), allowing us to prioritize highly promising candidate genes in a given chromosomal interval(s) of Arabidopsis thaliana and rice, Oryza sativa. By inferentially integrating cross-species information resources including genomes, transcriptomes, proteomes, localizomes, phenomes and literature, the system compares a user's query, such as phenotypic or functional keywords, with the literature associated with the relevant genes located within the interval. By utilizing orthologous and paralogous correspondences, PosMed-plus efficiently integrates cross-species information to facilitate the ranking of rice candidate genes based on evidence from other model species such as Arabidopsis. PosMed-plus is a plant science version of the PosMed system widely used by mammalian researchers, and provides both a powerful integrative search function and a rich integrative display of the integrated databases. PosMed-plus is the first cross-species integrated database that inferentially prioritizes candidate genes for forward genetics approaches in plant science, and will be expanded for wider use in plant upgrading in many species.
Thermal energy storage heat exchanger: Molten salt heat exchanger design for utility power plants
NASA Technical Reports Server (NTRS)
Ferarra, A.; Yenetchi, G.; Haslett, R.; Kosson, R.
1977-01-01
The use of thermal energy storage (TES) in the latent heat of molten salts as a means of conserving fossil fuels and lowering the cost of electric power was evaluated. Public utility systems provided electric power on demand. This demand is generally maximum during late weekday afternoons, with considerably lower overnight and weekend loads. Typically, the average demand is only 60% to 80% of peak load. As peak load increases, the present practice is to purchase power from other grid facilities or to bring older less efficient fossil-fuel plants on line which increase the cost of electric power. The widespread use of oil-fired boilers, gas turbine and diesel equipment to meet peaking loads depletes our oil-based energy resources. Heat exchangers utilizing molten salts can be used to level the energy consumption curve. The study begins with a demand analysis and the consideration of several existing modern fossil-fuel and nuclear power plants for use as models. Salts are evaluated for thermodynamic, economic, corrosive, and safety characteristics. Heat exchanger concepts are explored and heat exchanger designs are conceived. Finally, the economics of TES conversions in existing plants and new construction is analyzed. The study concluded that TES is feasible in electric power generation. Substantial data are presented for TES design, and reference material for further investigation of techniques is included.
Optimization of biogas production using MEMS based near infrared inline-sensor
NASA Astrophysics Data System (ADS)
Saupe, Ray; Seider, Thomas; Stock, Volker; Kujawski, Olaf; Otto, Thomas; Gessner, Thomas
2013-03-01
Due to climate protection and increasing oil prices, renewable energy is becoming extremely important. Anaerobic digestion is a particular environmental and resource-saving way of heat and power production in biogas plants. These plants can be operated decentralized and independent of weather conditions and allow peak load operation. To maximize energy production, plants should be operated at a high efficiency. That means the entire installed power production capacity (e.g. CHP) and biogas production have to be used. However, current plant utilization in many areas is significantly lower, which is economically and environmentally inefficient, since the biochemical process responds to fluctuations in boundary conditions, e.g. mixing in the conditions and substrate composition. At present only a few easily accessible parameters such as fill level, flow rates and temperature are determined on-line. Monitoring of substrate composition occurs only sporadically with the help of laboratory methods. Direct acquisition of substrate composition combined with a smart control and regulation concept enables significant improvement in plant efficiency. This requires a compact, reliable and cost-efficient sensor. It is for this reason that a MEMS sensor system based on NIR spectroscopy has been developed. Requirements are high accuracy, which is the basic condition for exact chemometric evaluation of the sample as well as optimized MEMS design and packaging in order to work in poor environmental conditions. Another issue is sample presentation, which needs an exact adopted optical-mechanical system. In this paper, the development and application of a MEMS-based analyzer for biogas plants will be explained. The above mentioned problems and challenges will be discussed. Measurement results will be shown to demonstrate its performance.
Mars, the Moon, and the Ends of the Earth: Autonomy for Small Reactor Power Systems
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wood, Richard Thomas
2008-01-01
In recent years, the National Aeronautics and Space Administration (NASA) has been considering deep space missions that utilize a small-reactor power system (SRPS) to provide energy for propulsion and spacecraft power. Additionally, application of SRPS modules as a planetary power source is being investigated to enable a continuous human presence for nonpolar lunar sites and on Mars. A SRPS can supply high-sustained power for space and surface applications that is both reliable and mass efficient. The use of small nuclear reactors for deep space or planetary missions presents some unique challenges regarding the operations and control of the power system.more » Current-generation terrestrial nuclear reactors employ varying degrees of human control and decision-making for operations and benefit from periodic human interaction for maintenance. In contrast, the control system of a SRPS employed for deep space missions must be able to accommodate unattended operations due to communications delays and periods of planetary occlusion while adapting to evolving or degraded conditions with no opportunity for repair or refurbishment. While surface power systems for planetary outposts face less extreme delays and periods of isolation and may benefit from limited maintenance capabilities, considerations such as human safety, resource limitations and usage priorities, and economics favor minimizing direct, continuous human interaction with the SRPS for online, dedicated power system management. Thus, a SRPS control system for space or planetary missions must provide capabilities for operational autonomy. For terrestrial reactors, large-scale power plants remain the preferred near-term option for nuclear power generation. However, the desire to reduce reliance on carbon-emitting power sources in developing countries may lead to increased consideration of SRPS modules for local power generation in remote regions that are characterized by emerging, less established infrastructures. Additionally, many Generation IV (Gen IV) reactor concepts have goals for optimizing investment recovery and economic efficiency that promote significant reductions in plant operations and maintenance staff over current-generation nuclear power plants. To accomplish these Gen IV goals and also address the SRPS remote-siting challenges, higher levels of automation, fault tolerance, and advanced diagnostic capabilities are needed to provide nearly autonomous operations with anticipatory maintenance. Essentially, the SRPS control system for several anticipated terrestrial applications can benefit from the kind of operational autonomy that is necessary for deep space and planetary SRPS-enabled missions. Investigation of the state of the technology for autonomous control confirmed that control systems with varying levels of autonomy have been employed in robotic, transportation, spacecraft, and manufacturing applications. As an example, NASA has pursued autonomy for spacecraft and surface exploration vehicles (e.g., rovers) to reduce mission costs, increase efficiency for communications between ground control and the vehicle, and enable independent operation of the vehicle during times of communications blackout. However, autonomous control has not been implemented for an operating terrestrial nuclear power plant nor has there been any experience beyond automating simple control loops for space reactors. Current automated control technologies for nuclear power plants are reasonably mature, and fully automated control of normal SRPS operations is clearly feasible. However, the space-based and remote terrestrial applications of SRPS modules require autonomous capabilities that can accommodate nonoptimum operations when degradation, failure, and other off-normal events challenge the performance of the reactor while immediate human intervention is not possible. The independent action provided by autonomous control, which is distinct from the more limited self action of automated control, can satisfy these conditions. Key characteristics that distinguish autonomous control include: (1) intelligence to confirm system performance and detect degraded or failed conditions, (2) optimization to minimize stress on SRPS components and efficiently react to operational events without compromising system integrity, (3) robustness to accommodate uncertainties and changing conditions, and (4) flexibility and adaptability to accommodate failures through reconfiguration among available control system elements or adjustment of control system strategies, algorithms, or parameters.« less
Range Performance of Bombers Powered by Turbine-Propeller Power Plants
NASA Technical Reports Server (NTRS)
Cline, Charles W.
1950-01-01
Calculations have been made to find range? attainable by bombers of gross weights from l40,000 to 300,000 pounds powered by turbine-propeller power plants. Only conventional configurations were considered and emphasis was placed upon using data for structural and aerodynamic characteristics which are typical of modern military airplanes. An effort was made to limit the various parameters invoked in the airplane configuration to practical values. Therefore, extremely high wing loadings, large amounts of sweepback, and very high aspect ratios have not been considered. Power-plant performance was based upon the performance of a typical turbine-propeller engine equipped with propellers designed to maintain high efficiencies at high-subsonic speeds. Results indicated, in general, that the greatest range, for a given gross weight, is obtained by airplanes of high wing loading, unless the higher cruising speeds associated with the high-wing-loading airplanes require-the use of thinner wing sections. Further results showed the effect of cruising at-high speeds, of operation at very high altitudes, and of carrying large bomb loads.
Schmitt, Kara
2012-01-01
Nuclear power is one of the ways that we can design an efficient sustainable future. Automation is the primary system used to assist operators in the task of monitoring and controlling nuclear power plants (NPP). Automation performs tasks such as assessing the status of the plant's operations as well as making real time life critical situational specific decisions. While the advantages and disadvantages of automation are well studied in variety of domains, accidents remind us that there is still vulnerability to unknown variables. This paper will look at the effects of automation within three NPP accidents and incidents and will consider why automation failed in preventing these accidents from occurring. It will also review the accidents at the Three Mile Island, Chernobyl, and Fukushima Daiichi NPP's in order to determine where better use of automation could have resulted in a more desirable outcome.
2016-10-28
constraints and wire routing issues. • Outside sites have more space, but require outdoor rated equipment (NEMA outdoor rated.. ) and more maintenance...sustainable power, in many different types, sizes and capacities, as follows: • Cogen Plant #1 B1579: 7.2MW gas-fired turbine at Substation “AA...Cogen Plant #2 B1991: (2) 4.6MW gas-fired turbines at “Gillespie” Substation • 300kW fuel cell at Substation “AA” • PPA: 1.015MW solar photovoltaic
Method and apparatus for steam mixing a nuclear fueled electricity generation system
Tsiklauri, Georgi V.; Durst, Bruce M.
1996-01-01
A method and apparatus for improving the efficiency and performance of a nuclear electrical generation system that comprises the addition of steam handling equipment to an existing plant that results in a surprising increase in plant performance. More particularly, a gas turbine electrical generation system with heat recovery boiler is installed along with a micro-jet high pressure and a low pressure mixer superheater. Depending upon plant characteristics, the existing moisture separator reheater (MSR) can be either augmented or done away with. The instant invention enables a reduction in T.sub.hot without a derating of the reactor unit, and improves efficiency of the plant's electrical conversion cycle. Coupled with this advantage is a possible extension of the plant's fuel cycle length due to an increased electrical conversion efficiency. The reduction in T.sub.hot further allows for a surprising extension of steam generator life. An additional advantage is the reduction in erosion/corrosion of secondary system components including turbine blades and diaphragms. The gas turbine generator used in the instant invention can also replace or augment existing peak or emergency power needs. Another benefit of the instant invention is the extension of plant life and the reduction of downtime due to refueling.
Thermoelectric energy conversion with solid electrolytes
NASA Astrophysics Data System (ADS)
Cole, T.
1983-09-01
The alkali metal thermoelectric converter (AMTEC) is a device for the direct conversion of heat to electrical energy. The sodium ion conductor beta-double prime-alumina is used to form a high-temperature regenerative concentration cell for elemental sodium. An AMTEC of mature design should have an efficiency of 20 to 40 percent, a power density of 0.5 kilowatt per kilogram or more, no moving parts, low maintenance requirements, high durability, and efficiency independent of size. It should be usable with high-temperature combustion, nuclear, or solar heat sources. Experiments have demonstrated the feasibility of the AMTEC and confirmed the theoretical analysis of the device. A wide range of applications from aerospace power to utility power plants appears possible.
Thermoelectric energy conversion with solid electrolytes.
Cole, T
1983-09-02
The alkali metal thermoelectric converter (AMTEC) is a device for the direct conversion of heat to electrical energy. The sodium ion conductor beta"- alumina is used to form a high-temperature regenerative concentration cell for elemental sodium. An AMTEC of mature design should have an efficiency of 20 to 40 percent, a power density of 0.5 kilowatt per kilogram or more, no moving parts, low maintenance requirements, high durability, and efficiency independent of size. It should be usable with high-temperature combustion, nuclear, or solar heat sources. Experiments have demonstrated the feasibility of the AMTEC and confirmed the theoretical analysis of the device. A wide range of applications from aerospace power to utility power plants appears possible.
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.
Study of boron behaviour in two Spanish coal combustion power plants.
Ochoa-González, Raquel; Cuesta, Aida Fuente; Córdoba, Patricia; Díaz-Somoano, Mercedes; Font, Oriol; López-Antón, M Antonia; Querol, Xavier; Martínez-Tarazona, M Rosa; Giménez, Antonio
2011-10-01
A full-scale field study was carried out at two Spanish coal-fired power plants equipped with electrostatic precipitator (ESP) and wet flue gas desulfurisation (FGD) systems to investigate the distribution of boron in coals, solid by-products, wastewater streams and flue gases. The results were obtained from the simultaneous sampling of solid, liquid and gaseous streams and their subsequent analysis in two different laboratories for purposes of comparison. Although the final aim of this study was to evaluate the partitioning of boron in a (co-)combustion power plant, special attention was paid to the analytical procedure for boron determination. A sample preparation procedure was optimised for coal and combustion by-products to overcome some specific shortcomings of the currently used acid digestion methods. In addition boron mass balances and removal efficiencies in ESP and FGD devices were calculated. Mass balance closures between 83 and 149% were obtained. During coal combustion, 95% of the incoming boron was collected in the fly ashes. The use of petroleum coke as co-combustible produced a decrease in the removal efficiency of the ESP (87%). Nevertheless, more than 90% of the remaining gaseous boron was eliminated via the FGD in the wastewater discharged from the scrubber, thereby causing environmental problems. Copyright © 2011 Elsevier Ltd. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Udomsri, Seksan, E-mail: seksan.udomsri@energy.kth.s; Martin, Andrew R.; Fransson, Torsten H.
Finding environmentally benign methods related to sound municipal solid waste (MSW) management is of highest priority in Southeast Asia. It is very important to study new approaches which can reduce waste generation and simultaneously enhance energy recovery. One concrete example of particular significance is the concept of hybrid dual-fuel power plants featuring MSW and another high-quality fuel like natural gas. The hybrid dual-fuel cycles provide significantly higher electrical efficiencies than a composite of separate single-fuel power plant (standalone gas turbine combined cycle and MSW incineration). Although hybrid versions are of great importance for energy conversion from MSW, an economic assessmentmore » of these systems must be addressed for a realistic appraisal of these technologies. This paper aims to further examine an economic assessment and energy model analysis of different conversion technologies. Energy models are developed to further refine the expected potential of MSW incineration with regards to energy recovery and environmental issues. Results show that MSW incineration can play role for greenhouse gas reduction, energy recovery and waste management. In Bangkok, the electric power production via conventional incineration and hybrid power plants can cover 2.5% and 8% of total electricity consumption, respectively. The hybrid power plants have a relative short payback period (5 years) and can further reduce the CO{sub 2} levels by 3% in comparison with current thermal power plants.« less
Udomsri, Seksan; Martin, Andrew R; Fransson, Torsten H
2010-07-01
Finding environmentally benign methods related to sound municipal solid waste (MSW) management is of highest priority in Southeast Asia. It is very important to study new approaches which can reduce waste generation and simultaneously enhance energy recovery. One concrete example of particular significance is the concept of hybrid dual-fuel power plants featuring MSW and another high-quality fuel like natural gas. The hybrid dual-fuel cycles provide significantly higher electrical efficiencies than a composite of separate single-fuel power plant (standalone gas turbine combined cycle and MSW incineration). Although hybrid versions are of great importance for energy conversion from MSW, an economic assessment of these systems must be addressed for a realistic appraisal of these technologies. This paper aims to further examine an economic assessment and energy model analysis of different conversion technologies. Energy models are developed to further refine the expected potential of MSW incineration with regards to energy recovery and environmental issues. Results show that MSW incineration can play role for greenhouse gas reduction, energy recovery and waste management. In Bangkok, the electric power production via conventional incineration and hybrid power plants can cover 2.5% and 8% of total electricity consumption, respectively. The hybrid power plants have a relative short payback period (5 years) and can further reduce the CO(2) levels by 3% in comparison with current thermal power plants. Copyright (c) 2010 Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Veselov, F. V.; Erokhina, I. V.; Makarova, A. S.; Khorshev, A. A.
2017-03-01
The article deals with issues of technical and economic substantiation of priorities and scopes of modernizing the existing thermal power plants (TPPs) in Russia to work out long-term forecasts of the development of the industry. The current situation in the TPP modernization trends is analyzed. The updated initial figures of the capital and operation costs are presented and the obtained estimates of the comparative efficiency of various investment decisions on modernization and equipment replacement at gas-and-oil-burning and coal-fired TPPs with regard to the main zones of the national Unified Power System (UPS) of Russia are cited. The results of optimization of the generating capacity structure underlie a study of alternative TPP modernization strategies that differ in the scope of switching to new technologies, capital intensity, and energy efficiency (decrease in the average heat rate). To provide an integral economic assessment of the above strategies, the authors modified the traditional approach based on determination of the overall discounted costs of power supply (least-cost planning) supplemented with a comparison by the weighted average wholesale price of the electricity. A method for prediction of the wholesale price is proposed reasoning from the direct and dual solutions of the optimization problem. The method can be adapted to various combinations of the mechanisms of payment for the electricity and the capacity on the basis of marginal and average costs. Energy and economic analysis showed that the opposite effects of reduction in the capital investment and fuel saving change in a nonlinear way as the scope of the switch to more advanced power generation technologies at the TPPs increases. As a consequence, a strategy for modernization of the existing power plants rational with respect to total costs of the power supply and wholesale electricity prices has been formulated. The strategy combines decisions on upgrade and replacement of the equipment at the existing power plants of various types. The basic parameters of the strategy for the future until 2035 are provided.
Method of operating a thermal engine powered by a chemical reaction
Ross, John; Escher, Claus
1988-01-01
The invention involves a novel method of increasing the efficiency of a thermal engine. Heat is generated by a non-linear chemical reaction of reactants, said heat being transferred to a thermal engine such as Rankine cycle power plant. The novel method includes externally perturbing one or more of the thermodynamic variables of said non-linear chemical reaction.
Method of operating a thermal engine powered by a chemical reaction
Ross, J.; Escher, C.
1988-06-07
The invention involves a novel method of increasing the efficiency of a thermal engine. Heat is generated by a non-linear chemical reaction of reactants, said heat being transferred to a thermal engine such as Rankine cycle power plant. The novel method includes externally perturbing one or more of the thermodynamic variables of said non-linear chemical reaction. 7 figs.
A robust gene-stacking method utilizing yeast assembly for plant synthetic biology
DOE Office of Scientific and Technical Information (OSTI.GOV)
Shih, Patrick M.; Vuu, Khanh; Mansoori, Nasim
The advent and growth of synthetic biology has demonstrated its potential as a promising avenue of research to address many societal needs. But, plant synthetic biology efforts have been hampered by a dearth of DNA part libraries, versatile transformation vectors and efficient assembly strategies. We describe a versatile system (named jStack) utilizing yeast homologous recombination to efficiently assemble DNA into plant transformation vectors. We also demonstrate how this method can facilitate pathway engineering of molecules of pharmaceutical interest, production of potential biofuels and shuffling of disease-resistance traits between crop species. Our approach provides a powerful alternative to conventional strategies formore » stacking genes and traits to address many impending environmental and agricultural challenges.« less
A robust gene-stacking method utilizing yeast assembly for plant synthetic biology
Shih, Patrick M.; Vuu, Khanh; Mansoori, Nasim; ...
2016-10-26
The advent and growth of synthetic biology has demonstrated its potential as a promising avenue of research to address many societal needs. But, plant synthetic biology efforts have been hampered by a dearth of DNA part libraries, versatile transformation vectors and efficient assembly strategies. We describe a versatile system (named jStack) utilizing yeast homologous recombination to efficiently assemble DNA into plant transformation vectors. We also demonstrate how this method can facilitate pathway engineering of molecules of pharmaceutical interest, production of potential biofuels and shuffling of disease-resistance traits between crop species. Our approach provides a powerful alternative to conventional strategies formore » stacking genes and traits to address many impending environmental and agricultural challenges.« less
Adaptive Neural Network Algorithm for Power Control in Nuclear Power Plants
NASA Astrophysics Data System (ADS)
Masri Husam Fayiz, Al
2017-01-01
The aim of this paper is to design, test and evaluate a prototype of an adaptive neural network algorithm for the power controlling system of a nuclear power plant. The task of power control in nuclear reactors is one of the fundamental tasks in this field. Therefore, researches are constantly conducted to ameliorate the power reactor control process. Currently, in the Department of Automation in the National Research Nuclear University (NRNU) MEPhI, numerous studies are utilizing various methodologies of artificial intelligence (expert systems, neural networks, fuzzy systems and genetic algorithms) to enhance the performance, safety, efficiency and reliability of nuclear power plants. In particular, a study of an adaptive artificial intelligent power regulator in the control systems of nuclear power reactors is being undertaken to enhance performance and to minimize the output error of the Automatic Power Controller (APC) on the grounds of a multifunctional computer analyzer (simulator) of the Water-Water Energetic Reactor known as Vodo-Vodyanoi Energetichesky Reaktor (VVER) in Russian. In this paper, a block diagram of an adaptive reactor power controller was built on the basis of an intelligent control algorithm. When implementing intelligent neural network principles, it is possible to improve the quality and dynamic of any control system in accordance with the principles of adaptive control. It is common knowledge that an adaptive control system permits adjusting the controller’s parameters according to the transitions in the characteristics of the control object or external disturbances. In this project, it is demonstrated that the propitious options for an automatic power controller in nuclear power plants is a control system constructed on intelligent neural network algorithms.
Water demand for electricity in deep decarbonisation scenarios: a multi-model assessment
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mouratiadou, I.; Bevione, M.; Bijl, D. L.
This study assesses the effects of deep electricity decarbonisation and shifts in the choice of power plant cooling technologies on global electricity water demand, using a suite of five integrated assessment models. We find that electricity sector decarbonisation results in co-benefits for water resources primarily due to the phase-out of water-intensive coal-based thermoelectric power generation, although these co-benefits vary substantially across decarbonisation scenarios. Wind and solar photovoltaic power represent a win-win option for both climate and water resources, but further expansion of nuclear or fossil- and biomass-fuelled power plants with carbon capture and storage may result in increased pressures onmore » the water environment. Further to these results, the paper provides insights on the most crucial factors of uncertainty with regards to future estimates of water demand. These estimates varied substantially across models in scenarios where the effects of decarbonisation on the electricity mix were less clear-cut. Future thermal and water efficiency improvements of power generation technologies and demand-side energy efficiency improvements were also identified to be important factors of uncertainty. We conclude that in order to ensure positive effects of decarbonisation on water resources, climate policy should be combined with technology-specific energy and/or water policies.« less
Monitoring of hot pipes at the power plant Neurath using guided waves
NASA Astrophysics Data System (ADS)
Weihnacht, Bianca; Klesse, Thomas; Neubeck, Robert; Schubert, Lars
2013-04-01
In order to reduce the CO2-emissions and to increase the energy efficiency, the operating temperatures of power plants will be increased up to 720°C. This demands for novel high-performance steels in the piping systems. Higher temperatures lead to a higher risk of damage and have a direct impact on the structure stability and the deposition structure. Adequately trusted results for the prediction of the residual service life of those high strength steels are not available so far. To overcome these problems the implementation of an online monitoring system in addition to periodic testing is needed. RWE operates the lignite power plant Neurath. All test and research activities have to be checked regarding their safety and have to be coordinated with the business operation of the plant. An extra bypass was established for this research and made the investigations independent from the power plant operating. In order to protect the actuators and sensors from the heat radiated from the pipe, waveguides were welded to the bypass. The data was evaluated regarding their dependencies on the environmental influences like temperature and correction algorithms were developed. Furthermore, damages were introduced into the pipe with diameters of 8 mm to 10 mm and successfully detected by the acoustic method.
Nitrogen oxides emissions from thermal power plants in china: current status and future predictions.
Tian, Hezhong; Liu, Kaiyun; Hao, Jiming; Wang, Yan; Gao, Jiajia; Qiu, Peipei; Zhu, Chuanyong
2013-10-01
Increasing emissions of nitrogen oxides (NOx) over the Chinese mainland have been of great concern due to their adverse impacts on regional air quality and public health. To explore and obtain the temporal and spatial characteristics of NOx emissions from thermal power plants in China, a unit-based method is developed. The method assesses NOx emissions based on detailed information on unit capacity, boiler and burner patterns, feed fuel types, emission control technologies, and geographical locations. The national total NOx emissions in 2010 are estimated at 7801.6 kt, of which 5495.8 kt is released from coal-fired power plant units of considerable size between 300 and 1000 MW. The top provincial emitter is Shandong where plants are densely concentrated. The average NOx-intensity is estimated at 2.28 g/kWh, markedly higher than that of developed countries, mainly owing to the inadequate application of high-efficiency denitrification devices such as selective catalytic reduction (SCR). Future NOx emissions are predicted by applying scenario analysis, indicating that a reduction of about 40% by the year 2020 can be achieved compared with emissions in 2010. These results suggest that NOx emissions from Chinese thermal power plants could be substantially mitigated within 10 years if reasonable control measures were implemented effectively.
Radioactivity of coals and ash and slag wastes at coal-fired thermal power plants
NASA Astrophysics Data System (ADS)
Krylov, D. A.; Sidorova, G. P.
2013-04-01
This paper presents an analysis of published data on the content of radioactive nuclides in coals originating from various coal deposits, and in ash and slag wastes produced at coal-fired thermal power plants, as well as in fly ash emitted from thermal power plants into the atmosphere. Problems related to the use of coals with an elevated content of natural radionuclides (NRNs) and methods of their solution implemented at the Urtuyskoe coalfield are dealt with. Data on the analysis of Transbaikal coals for the NRN content, as well as weighted mean content of uranium and thorium in coals from the Siberian Region, are given. In order to reduce irradiation of plant personnel and the population of the areas where coal producers and coal-fired thermal power plants are located, it is necessary to organize very careful control of the NRN content in both coals and products of their combustion that are released into the environment. To solve the problem related to the control of radioactivity, the centralized approach and creation of a proper normative base are needed. Experience gained in developing the Urtuyskoe coalfield shows that it is possible to create an efficient system of coal quality control with respect to the radiation hygiene factor and provide protection of the environment and health of the population.
Preliminary thermodynamic study for an efficient turbo-blower external combustion Rankine cycle
NASA Astrophysics Data System (ADS)
Romero Gómez, Manuel; Romero Gómez, Javier; Ferreiro Garcia, Ramón; Baaliña Insua, Álvaro
2014-08-01
This research paper presents a preliminary thermodynamic study of an innovative power plant operating under a Rankine cycle fed by an external combustion system with turbo-blower (TB). The power plant comprises an external combustion system for natural gas, where the combustion gases yield their thermal energy, through a heat exchanger, to a carbon dioxide Rankine cycle operating under supercritical conditions and with quasi-critical condensation. The TB exploits the energy from the pressurised exhaust gases for compressing the combustion air. The study is focused on the comparison of the combustion system's conventional technology with that of the proposed. An energy analysis is carried out and the effect of the flue gas pressure on the efficiency and on the heat transfer in the heat exchanger is studied. The coupling of the TB results in an increase in efficiency and of the convection coefficient of the flue gas with pressure, favouring a reduced volume of the heat exchanger. The proposed innovative system achieves increases in efficiency of around 12 % as well as a decrease in the heat exchanger volume of 3/5 compared with the conventional technology without TB.
Rao, Anand B; Rubin, Edward S
2002-10-15
Capture and sequestration of CO2 from fossil fuel power plants is gaining widespread interest as a potential method of controlling greenhouse gas emissions. Performance and cost models of an amine (MEA)-based CO2 absorption system for postcombustion flue gas applications have been developed and integrated with an existing power plant modeling framework that includes multipollutant control technologies for other regulated emissions. The integrated model has been applied to study the feasibility and cost of carbon capture and sequestration at both new and existing coal-burning power plants. The cost of carbon avoidance was shown to depend strongly on assumptions about the reference plant design, details of the CO2 capture system design, interactions with other pollution control systems, and method of CO2 storage. The CO2 avoidance cost for retrofit systems was found to be generally higher than for new plants, mainly because of the higher energy penalty resulting from less efficient heat integration as well as site-specific difficulties typically encountered in retrofit applications. For all cases, a small reduction in CO2 capture cost was afforded by the SO2 emission trading credits generated by amine-based capture systems. Efforts are underway to model a broader suite of carbon capture and sequestration technologies for more comprehensive assessments in the context of multipollutant environmental management.
Foxtail Mosaic Virus-Induced Gene Silencing in Monocot Plants.
Liu, Na; Xie, Ke; Jia, Qi; Zhao, Jinping; Chen, Tianyuan; Li, Huangai; Wei, Xiang; Diao, Xianmin; Hong, Yiguo; Liu, Yule
2016-07-01
Virus-induced gene silencing (VIGS) is a powerful technique to study gene function in plants. However, very few VIGS vectors are available for monocot plants. Here we report that Foxtail mosaic virus (FoMV) can be engineered as an effective VIGS system to induce efficient silencing of endogenous genes in monocot plants including barley (Hordeum vulgare L.), wheat (Triticum aestivum) and foxtail millet (Setaria italica). This is evidenced by FoMV-based silencing of phytoene desaturase (PDS) and magnesium chelatase in barley, of PDS and Cloroplastos alterados1 in foxtail millet and wheat, and of an additional gene IspH in foxtail millet. Silencing of these genes resulted in photobleached or chlorosis phenotypes in barley, wheat, and foxtail millet. Furthermore, our FoMV-based gene silencing is the first VIGS system reported for foxtail millet, an important C4 model plant. It may provide an efficient toolbox for high-throughput functional genomics in economically important monocot crops. © 2016 American Society of Plant Biologists. All Rights Reserved.
NASA Astrophysics Data System (ADS)
Nur, T. B.; Pane, Z.; Amin, M. N.
2017-03-01
Due to increasing oil and gas demand with the depletion of fossil resources in the current situation make efficient energy systems and alternative energy conversion processes are urgently needed. With the great potential of resources in Indonesia, make biomass has been considered as one of major potential fuel and renewable resource for the near future. In this paper, the potential of palm oil mill waste as a bioenergy source has been investigated. An organic Rankine cycle (ORC) small scale power plant has been preliminary designed to generate electricity. The working fluid candidates for the ORC plant based on the heat source temperature domains have been investigated. The ORC system with a regenerator has higher thermal efficiency than the basic ORC system. The study demonstrates the technical feasibility of ORC solutions in terms of resources optimizations and reducing of greenhouse gas emissions.
Combustion distribution control using the extremum seeking algorithm
NASA Astrophysics Data System (ADS)
Marjanovic, A.; Krstic, M.; Djurovic, Z.; Kvascev, G.; Papic, V.
2014-12-01
Quality regulation of the combustion process inside the furnace is the basis of high demands for increasing robustness, safety and efficiency of thermal power plants. The paper considers the possibility of spatial temperature distribution control inside the boiler, based on the correction of distribution of coal over the mills. Such control system ensures the maintenance of the flame focus away from the walls of the boiler, and thus preserves the equipment and reduces the possibility of ash slugging. At the same time, uniform heat dissipation over mills enhances the energy efficiency of the boiler, while reducing the pollution of the system. A constrained multivariable extremum seeking algorithm is proposed as a tool for combustion process optimization with the main objective of centralizing the flame in the furnace. Simulations are conducted on a model corresponding to the 350MW boiler of the Nikola Tesla Power Plant, in Obrenovac, Serbia.
Supercritical Brayton Cycle Nuclear Power System Concepts
NASA Astrophysics Data System (ADS)
Wright, Steven A.
2007-01-01
Both the NASA and DOE have programs that are investigating advanced power conversion cycles for planetary surface power on the moon or Mars, and for next generation nuclear power plants on earth. The gas Brayton cycle offers many practical solutions for space nuclear power systems and was selected as the nuclear power system of choice for the NASA Prometheus project. An alternative Brayton cycle that offers high efficiency at a lower reactor coolant outlet temperature is the supercritical Brayton cycle (SCBC). The supercritical cycle is a true Brayton cycle because it uses a single phase fluid with a compressor inlet temperature that is just above the critical point of the fluid. This paper describes the use of a supercritical Brayton cycle that achieves a cycle efficiency of 26.6% with a peak coolant temperature of 750 K and for a compressor inlet temperature of 390 K. The working fluid uses a clear odorless, nontoxic refrigerant C318 perflurocarbon (C4F8) that always operates in the gas phase. This coolant was selected because it has a critical temperature and pressure of 388.38 K and 2.777 MPa. The relatively high critical temperature allows for efficient thermal radiation that keeps the radiator mass small. The SCBC achieves high efficiency because the loop design takes advantage of the non-ideal nature of the coolant equation of state just above the critical point. The lower coolant temperature means that metal fuels, uranium oxide fuels, and uranium zirconium hydride fuels with stainless steel, ferretic steel, or superalloy cladding can be used with little mass penalty or reduction in cycle efficiency. The reactor can use liquid-metal coolants and no high temperature heat exchangers need to be developed. Indirect gas cooling or perhaps even direct gas cooling can be used if the C4F8 coolant is found to be sufficiently radiation tolerant. Other fluids can also be used in the supercritical Brayton cycle including Propane (C3H8, Tcritical = 369 K) and Hexane (C6H14, Tcritical = 506.1 K) provided they have adequate chemical compatibility and stability. Overall the use of supercritical Brayton cycles may offer ``break through'' operating capabilities for space nuclear power plants because high efficiencies can be achieved a very low reactor operating temperatures which in turn allows for the use of available fuels, cladding, and structural materials.
UF6 breeder reactor power plants for electric power generation
NASA Technical Reports Server (NTRS)
Rust, J. H.; Clement, J. D.; Hohl, F.
1976-01-01
The reactor concept analyzed is a U-233F6 core surrounded by a molten salt (Li(7)F, BeF2, ThF4) blanket. Nuclear survey calculations were carried out for both spherical and cylindrical geometries. Thermodynamic cycle calculations were performed for a variety of Rankine cycles. A conceptual design is presented along with a system layout for a 1000 MW stationary power plant. Advantages of the gas core breeder reactor (GCBR) are as follows: (1) high efficiency; (2) simplified on-line reprocessing; (3) inherent safety considerations; (4) high breeding ratio; (5) possibility of burning all or most of the long-lived nuclear waste actinides; and (6) possibility of extrapolating the technology to higher temperatures and MHD direct conversion.
NASA Astrophysics Data System (ADS)
Shchelik, S. V.; Pavlov, A. S.
2013-07-01
Results of work on restoring the service properties of filtering material used in the high-temperature reactor coolant purification system of a VVER-1000 reactor are presented. A quantitative assessment is given to the effect from subjecting a high-temperature sorbent to backwashing operations carried out with the use of regular capacities available in the design process circuit in the first years of operation of Unit 3 at the Kalinin nuclear power plant. Approaches to optimizing this process are suggested. A conceptual idea about comprehensively solving the problem of achieving more efficient and safe operation of the high-temperature active water treatment system (AWT-1) on a nuclear power industry-wide scale is outlined.
Geysers advanced direct contact condenser research
DOE Office of Scientific and Technical Information (OSTI.GOV)
Henderson, J.; Bahning, T.; Bharathan, D.
1997-12-31
The first geothermal application of the Advanced Direct Contact Condenser (ADCC) technology developed by the National Renewable Energy Laboratory (NREL) is now operational and is being tested at The Geysers Power Plant Unit 11. This major research effort is being supported through the combined efforts of NREL, The Department of Energy (DOE), and Pacific Gas and Electric (PG&E). NREL and PG&E have entered into a Cooperative Research And Development Agreement (CRADA) for a project to improve the direct-contact condenser performance at The Geysers Power Plant. This project is the first geothermal adaptation of an advanced condenser design developed for themore » Ocean Thermal Energy Conversion (OTEC) systems. PG&E expects this technology to improve power plant performance and to help extend the life of the steam field by using steam more efficiently. In accordance with the CRADA, no money is transferred between the contracting parties. In this case the Department of Energy is funding NREL for their efforts in this project and PG&E is contributing funds in kind. Successful application of this technology at The Geysers will provide a basis for NREL to continue to develop this technology for other geothermal and fossil power plant systems.« less
Growth and development of Arabidopsis thaliana under single-wavelength red and blue laser light.
Ooi, Amanda; Wong, Aloysius; Ng, Tien Khee; Marondedze, Claudius; Gehring, Christoph; Ooi, Boon S
2016-09-23
Indoor horticulture offers a sensible solution for sustainable food production and is becoming increasingly widespread. However, it incurs high energy and cost due to the use of artificial lighting such as high-pressure sodium lamps, fluorescent light or increasingly, the light-emitting diodes (LEDs). The energy efficiency and light quality of currently available horticultural lighting is suboptimal, and therefore less than ideal for sustainable and cost-effective large-scale plant production. Here, we demonstrate the use of high-powered single-wavelength lasers for indoor horticulture. They are highly energy-efficient and can be remotely guided to the site of plant growth, thus reducing on-site heat accumulation. Furthermore, laser beams can be tailored to match the absorption profiles of different plant species. We have developed a prototype laser growth chamber and demonstrate that plants grown under laser illumination can complete a full growth cycle from seed to seed with phenotypes resembling those of plants grown under LEDs reported previously. Importantly, the plants have lower expression of proteins diagnostic for light and radiation stress. The phenotypical, biochemical and proteome data show that the single-wavelength laser light is suitable for plant growth and therefore, potentially able to unlock the advantages of this next generation lighting technology for highly energy-efficient horticulture.
Growth and development of Arabidopsis thaliana under single-wavelength red and blue laser light
Ooi, Amanda; Wong, Aloysius; Ng, Tien Khee; Marondedze, Claudius; Gehring, Christoph; Ooi, Boon S.
2016-01-01
Indoor horticulture offers a sensible solution for sustainable food production and is becoming increasingly widespread. However, it incurs high energy and cost due to the use of artificial lighting such as high-pressure sodium lamps, fluorescent light or increasingly, the light-emitting diodes (LEDs). The energy efficiency and light quality of currently available horticultural lighting is suboptimal, and therefore less than ideal for sustainable and cost-effective large-scale plant production. Here, we demonstrate the use of high-powered single-wavelength lasers for indoor horticulture. They are highly energy-efficient and can be remotely guided to the site of plant growth, thus reducing on-site heat accumulation. Furthermore, laser beams can be tailored to match the absorption profiles of different plant species. We have developed a prototype laser growth chamber and demonstrate that plants grown under laser illumination can complete a full growth cycle from seed to seed with phenotypes resembling those of plants grown under LEDs reported previously. Importantly, the plants have lower expression of proteins diagnostic for light and radiation stress. The phenotypical, biochemical and proteome data show that the single-wavelength laser light is suitable for plant growth and therefore, potentially able to unlock the advantages of this next generation lighting technology for highly energy-efficient horticulture. PMID:27659906
Modeling and Economic Analysis of Power Grid Operations in a Water Constrained System
NASA Astrophysics Data System (ADS)
Zhou, Z.; Xia, Y.; Veselka, T.; Yan, E.; Betrie, G.; Qiu, F.
2016-12-01
The power sector is the largest water user in the United States. Depending on the cooling technology employed at a facility, steam-electric power stations withdrawal and consume large amounts of water for each megawatt hour of electricity generated. The amounts are dependent on many factors, including ambient air and water temperatures, cooling technology, etc. Water demands from most economic sectors are typically highest during summertime. For most systems, this coincides with peak electricity demand and consequently a high demand for thermal power plant cooling water. Supplies however are sometimes limited due to seasonal precipitation fluctuations including sporadic droughts that lead to water scarcity. When this occurs there is an impact on both unit commitments and the real-time dispatch. In this work, we model the cooling efficiency of several different types of thermal power generation technologies as a function of power output level and daily temperature profiles. Unit specific relationships are then integrated in a power grid operational model that minimizes total grid production cost while reliably meeting hourly loads. Grid operation is subject to power plant physical constraints, transmission limitations, water availability and environmental constraints such as power plant water exit temperature limits. The model is applied to a standard IEEE-118 bus system under various water availability scenarios. Results show that water availability has a significant impact on power grid economics.
Multi-Stage Metering Mechanism for Transplanting of Vegetable Seedlings in Paper Pots
NASA Astrophysics Data System (ADS)
Nandede, B. M.; Raheman, H.
2015-12-01
A multi-stage rotating cup type metering mechanism was developed for transplanting of vegetable seedlings of tomato, brinjal and chili raised in paper pots. The developed setup consisted of a seedling feeding wheel, metering wheel, fixed slotted plate, seedling delivery tube, furrow opener, furrow closer and a power transmission system. Its evaluation was carried out with pot seedlings of tomato, brinjal and chili of 8-11 cm height at five forward speeds (0.6, 0.9, 1.2, 2.2 and 3.2 km/h) and two plant spacings (45 and 60 cm) in controlled soil bin condition. The mean values of feeding efficiency, conveying efficiency, planting efficiency and overall efficiency of the multistage metering unit were observed to be higher than 90 % for forward speeds of 0.6 to 2.2 km/h. With further increase in speed to 3.2 km/h, the feeding and conveying efficiency were observed to be higher than 90 %, whereas, the planting efficiency drastically reduced to around 50 % due to the problem in getting the pot seedlings vertically in the furrow. Also the seedlings were falling into the furrow at an angle greater than 70° to the vertical, hence not suitable for transplanting.
International water and steam quality standards on thermal power plants at all-volatile treatment
NASA Astrophysics Data System (ADS)
Petrova, T. I.; Orlov, K. A.; Dooley, R. B.
2016-12-01
One of the methods for the improvement of reliability and efficiency of the equipment at heat power plants is the decrease in the rate of corrosion of structural materials and sedimentation in water/steam circuit. These processes can be reduced to minimum by using the water with low impurity content and coolant treatment. For many years, water and steam quality standards were developed in various countries (United States, Germany, Japan, etc.) for specific types of equipment. The International Association for the Properties of Water and Steam (IAPWS), which brings together specialists from 21 countries, developed the water and steam quality standards for various types of power equipment based on theoretical studies and long-term operating experience of power equipment. Recently, various water-chemistry conditions are applied on heatpower equipment including conventional boilers and HRSGs with combined cycle power plants (Combined Cycle Power Plants (CCPP)). In paper, the maintenance conditions of water chemistry with ammonia or volatile amine dosing are described: reducing AVT(R), oxidizing AVT(O), and oxygen OT. Each of them is provided by the water and steam quality standards and recommendations are given on their maintenance under various operation conditions. It is noted that the quality control of heat carrier must be carried out with a particular care on the HPPs with combined cycle gas turbine units, where frequent starts and halts are performed.
Final Technical Report - Modernization of the Boulder Canyon Hydroelectric Project
DOE Office of Scientific and Technical Information (OSTI.GOV)
Taddeucci, Joe
2013-03-29
The Boulder Canyon Hydroelectric Project (BCH) was purchased by the City of Boulder, CO (the city) in 2001. Project facilities were originally constructed in 1910 and upgraded in the 1930s and 1940s. By 2009, the two 10 MW turbine/generators had reached or were nearing the end of their useful lives. One generator had grounded out and was beyond repair, reducing plant capacity to 10 MW. The remaining 10 MW unit was expected to fail at any time. When the BCH power plant was originally constructed, a sizeable water supply was available for the sole purpose of hydroelectric power generation. Betweenmore » 1950 and 2001, that water supply had gradually been converted to municipal water supply by the city. By 2001, the water available for hydroelectric power generation at BCH could not support even one 10 MW unit. Boulder lacked the financial resources to modernize the facilities, and Boulder anticipated that when the single, operational historical unit failed, the project would cease operation. In 2009, the City of Boulder applied for and received a U.S. Department of Energy (DOE) grant for $1.18 million toward a total estimated project cost of $5.155 million to modernize BCH. The federal funding allowed Boulder to move forward with plant modifications that would ensure BCH would continue operation. Federal funding was made available through the American Recovery and Reinvestment Act (ARRA) of 2009. Boulder determined that a single 5 MW turbine/generator would be the most appropriate capacity, given the reduced water supply to the plant. Average annual BCH generation with the old 10 MW unit had been about 8,500 MW-hr, whereas annual generation with a new, efficient turbine could average 11,000 to 12,000 MW-hr. The incremental change in annual generation represents a 30% increase in generation over pre-project conditions. The old turbine/generator was a single nozzle Pelton turbine with a 5-to-1 flow turndown and a maximum turbine/generator efficiency of 82%. The new unit is a double nozzle Pelton turbine with a 10-to-1 flow turndown and a maximum turbine/generator efficiency of 88%. This alone represents a 6% increase in overall efficiency. The old turbine operated at low efficiencies due to age and non-optimal sizing of the turbine for the water flow available to the unit. It was shut down whenever water flow dropped to less than 4-5 cfs, and at that flow, efficiency was 55 to 60%. The new turbine will operate in the range of 70 to 88% efficiency through a large portion of the existing flow range and would only have to be shut down at flow rates less than 3.7 cfs. Efficiency is expected to increase by 15-30%, depending on flow. In addition to the installation of new equipment, other goals for the project included: Increasing safety at Boulder Canyon Hydro Increasing protection of the Boulder Creek environment Modernizing and integrating control equipment into Boulder's municipal water supply system, and Preserving significant historical engineering information prior to power plant modernization. From January 1, 2010 through December 31, 2012, combined consultant and contractor personnel hours paid for by both the city and the federal government have totaled approximately 40,000. This equates roughly to seven people working full time on the project from January 2010 through December 2012. This project also involved considerable material expense (steel pipe, a variety of valves, electrical equipment, and the various components of the turbine and generator), which were not accounted for in terms of hours spent on the project. However, the material expense related to this project did help to create or preserve manufacturing/industrial jobs throughout the United States. As required by ARRA, the various components of the hydroelectric project were manufactured or substantially transformed in the U.S. BCH is eligible for nomination to the National Register of Historic Places due in part to its unique engineering features and innovative construction techniques. Special efforts were directed toward documenting the (largely original) interior of the plant and installing new equipment without modifying the power plant exterior in order to preserve the historical significance of the facility. In addition, a significant portion of the historical equipment within the power plant was preserved in place. The modernization project began with DOE grant award on January 1, 2010, and the project was completed on December 31, 2012. In addition to city engineering and hydroelectric staff, major project participants included AECOM (design/engineering) Canyon Industries (turbine/generator manufacture), Gracon Corporation (general construction contractor), Exponential Engineering Company (electrical engineering) and URS Corporation (historical documentation), as well as numerous other subcontractors and consultants.« less
Design and Control of Integrated Systems for Hydrogen Production and Power Generation
NASA Astrophysics Data System (ADS)
Georgis, Dimitrios
Growing concerns on CO2 emissions have led to the development of highly efficient power plants. Options for increased energy efficiencies include alternative energy conversion pathways, energy integration and process intensification. Solid oxide fuel cells (SOFC) constitute a promising alternative for power generation since they convert the chemical energy electrochemically directly to electricity. Their high operating temperature shows potential for energy integration with energy intensive units (e.g. steam reforming reactors). Although energy integration is an essential tool for increased efficiencies, it leads to highly complex process schemes with rich dynamic behavior, which are challenging to control. Furthermore, the use of process intensification for increased energy efficiency imposes an additional control challenge. This dissertation identifies and proposes solutions on design, operational and control challenges of integrated systems for hydrogen production and power generation. Initially, a study on energy integrated SOFC systems is presented. Design alternatives are identified, control strategies are proposed for each alternative and their validity is evaluated under different operational scenarios. The operational range of the proposed control strategies is also analyzed. Next, thermal management of water gas shift membrane reactors, which are a typical application of process intensification, is considered. Design and operational objectives are identified and a control strategy is proposed employing advanced control algorithms. The performance of the proposed control strategy is evaluated and compared with classical control strategies. Finally SOFC systems for combined heat and power applications are considered. Multiple recycle loops are placed to increase design flexibility. Different operational objectives are identified and a nonlinear optimization problem is formulated. Optimal designs are obtained and their features are discussed and compared. The results of the dissertation provide a deeper understanding on the design, operational and control challenges of the above systems and can potentially guide further commercialization efforts. In addition to this, the results can be generalized and used for applications from the transportation and residential sector to large--scale power plants.
PVMirrors: Hybrid PV/CSP collectors that enable lower LCOEs
NASA Astrophysics Data System (ADS)
Fisher, Kate; Yu, Zhengshan Jason; Striling, Rob; Holman, Zachary
2017-06-01
The primary challenge with concentrating solar power (CSP) is that the conversion efficiency is low—and the cost high—compared to that of photovoltaics (PV), and the primary challenge with PV is that the energy generated cannot be stored cost effectively. We introduce a technology that hybridizes CSP and PV, resulting in power plants with high energy conversion efficiency and affordable storage. This is accomplished by replacing silvered troughs (or heliostat facets) with "PVMirrors" that and direct photons of each wavelength to the converter (PV or thermal) that may best use them. A PVMirror looks like a curved PV module that includes a spectrum-splitting dichroic mirror film; this film, which is the heart of the technology, transmits near-infrared light to the underlying silicon PV cells while reflecting both longer and shorter wavelengths to a thermal absorber tube. This paper investigates the optical performance of dichroic mirror film, the specularity of PVMirrors, and the anticipated levelized cost of energy (LCOE) from a PVMirror power plant. PVMirrors are found to decrease LCOE by more than 15% relative to CSP while retaining full dispatchability.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Paul, P.; Bhattacharyya, D.; Turton, R.
2012-01-01
Future integrated gasification combined cycle (IGCC) power plants with CO{sub 2} capture will face stricter operational and environmental constraints. Accurate values of relevant states/outputs/disturbances are needed to satisfy these constraints and to maximize the operational efficiency. Unfortunately, a number of these process variables cannot be measured while a number of them can be measured, but have low precision, reliability, or signal-to-noise ratio. In this work, a sensor placement (SP) algorithm is developed for optimal selection of sensor location, number, and type that can maximize the plant efficiency and result in a desired precision of the relevant measured/unmeasured states. In thismore » work, an SP algorithm is developed for an selective, dual-stage Selexol-based acid gas removal (AGR) unit for an IGCC plant with pre-combustion CO{sub 2} capture. A comprehensive nonlinear dynamic model of the AGR unit is developed in Aspen Plus Dynamics® (APD) and used to generate a linear state-space model that is used in the SP algorithm. The SP algorithm is developed with the assumption that an optimal Kalman filter will be implemented in the plant for state and disturbance estimation. The algorithm is developed assuming steady-state Kalman filtering and steady-state operation of the plant. The control system is considered to operate based on the estimated states and thereby, captures the effects of the SP algorithm on the overall plant efficiency. The optimization problem is solved by Genetic Algorithm (GA) considering both linear and nonlinear equality and inequality constraints. Due to the very large number of candidate sets available for sensor placement and because of the long time that it takes to solve the constrained optimization problem that includes more than 1000 states, solution of this problem is computationally expensive. For reducing the computation time, parallel computing is performed using the Distributed Computing Server (DCS®) and the Parallel Computing® toolbox from Mathworks®. In this presentation, we will share our experience in setting up parallel computing using GA in the MATLAB® environment and present the overall approach for achieving higher computational efficiency in this framework.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Paul, P.; Bhattacharyya, D.; Turton, R.
2012-01-01
Future integrated gasification combined cycle (IGCC) power plants with CO{sub 2} capture will face stricter operational and environmental constraints. Accurate values of relevant states/outputs/disturbances are needed to satisfy these constraints and to maximize the operational efficiency. Unfortunately, a number of these process variables cannot be measured while a number of them can be measured, but have low precision, reliability, or signal-to-noise ratio. In this work, a sensor placement (SP) algorithm is developed for optimal selection of sensor location, number, and type that can maximize the plant efficiency and result in a desired precision of the relevant measured/unmeasured states. In thismore » work, an SP algorithm is developed for an selective, dual-stage Selexol-based acid gas removal (AGR) unit for an IGCC plant with pre-combustion CO{sub 2} capture. A comprehensive nonlinear dynamic model of the AGR unit is developed in Aspen Plus Dynamics® (APD) and used to generate a linear state-space model that is used in the SP algorithm. The SP algorithm is developed with the assumption that an optimal Kalman filter will be implemented in the plant for state and disturbance estimation. The algorithm is developed assuming steady-state Kalman filtering and steady-state operation of the plant. The control system is considered to operate based on the estimated states and thereby, captures the effects of the SP algorithm on the overall plant efficiency. The optimization problem is solved by Genetic Algorithm (GA) considering both linear and nonlinear equality and inequality constraints. Due to the very large number of candidate sets available for sensor placement and because of the long time that it takes to solve the constrained optimization problem that includes more than 1000 states, solution of this problem is computationally expensive. For reducing the computation time, parallel computing is performed using the Distributed Computing Server (DCS®) and the Parallel Computing® toolbox from Mathworks®. In this presentation, we will share our experience in setting up parallel computing using GA in the MATLAB® environment and present the overall approach for achieving higher computational efficiency in this framework.« less
Bizarro, João P S; Rodrigues, Paulo
2012-11-01
For work-producing heat engines, or work-consuming refrigerators and heat pumps, the percentage decrease caused by friction in their efficiencies, or coefficients of performance (COP's), is approximately given by the ratio W(fric)/W between the work spent against friction forces and the work performed by, or delivered to, the working fluid. This universal scaling, which applies in the limit of small friction (W(fric)/W ~ 20%) and when the engine's figures of merit (FOM's, either efficiencies or COP's) do not come too close to unity (no higher than, say, 0.5 in the case of heat-engine efficiencies), allows a simple and quick estimate of the impact that friction losses can have on the FOM's of thermal engines and plants, or of the level of those losses from the observed and predicted FOM's. In the case of refrigerators and heat pumps, if W(fric)/W ~ 20% is not ensured (actually a condition that can be largely relaxed for heat engines), the COP percentage decrease due to friction approaches asymptotically (W(fric)/W)/(1+W(fric)/W) instead of W(fric)/W. Estimates for the level of frictional losses using the Carnot (or, for heat engines and power plants only, the Curzon-Ahlborn) predictions and observed FOM's of real power plants, heat engines, refrigerators, and heat pumps show that they usually operate in domains where these behaviors are valid.
Validation of a program for supercritical power plant calculations
NASA Astrophysics Data System (ADS)
Kotowicz, Janusz; Łukowicz, Henryk; Bartela, Łukasz; Michalski, Sebastian
2011-12-01
This article describes the validation of a supercritical steam cycle. The cycle model was created with the commercial program GateCycle and validated using in-house code of the Institute of Power Engineering and Turbomachinery. The Institute's in-house code has been used extensively for industrial power plants calculations with good results. In the first step of the validation process, assumptions were made about the live steam temperature and pressure, net power, characteristic quantities for high- and low-pressure regenerative heat exchangers and pressure losses in heat exchangers. These assumptions were then used to develop a steam cycle model in Gate-Cycle and a model based on the code developed in-house at the Institute of Power Engineering and Turbomachinery. Properties, such as thermodynamic parameters at characteristic points of the steam cycle, net power values and efficiencies, heat provided to the steam cycle and heat taken from the steam cycle, were compared. The last step of the analysis was calculation of relative errors of compared values. The method used for relative error calculations is presented in the paper. The assigned relative errors are very slight, generally not exceeding 0.1%. Based on our analysis, it can be concluded that using the GateCycle software for calculations of supercritical power plants is possible.
Chiumenti, Alessandro; da Borso, Francesco; Limina, Sonia
2018-01-01
For years, anaerobic digestion processes have been implemented for the management of organic wastes, agricultural residues, and animal manure. Wet anaerobic digestion still represents the most common technology, while dry fermentation, dedicated to the treatment of solid inputs (TS>20%) can be considered as an emerging technology, not in terms of technological maturity, but of diffusion. The first agricultural dry anaerobic digestion plant constructed in Italy was monitored from the start-up, for over a year. The plant was fed with manure and agricultural products, such as corn silage, triticale, ryegrass, alfalfa, and straw. Three Combined Heat and Power units, for a total installed power of 910kW e , converted biogas into thermal and electric energy. The monitoring included the determination of quality and quantity of input feedstocks, of digestate (including recirculation rate), of leachate, biogas quality (CH 4 , CO 2 , H 2 S), biogas yield, energy production, labor requirement for loading, and unloading operations. The results of the monitoring were compared to performance data obtained in several full scale wet digestion plants. The dry fermentation plant revealed a start-up phase that lasted several months, during which the average power resulted in 641kW e (70.4% of nominal power), and the last period the power resulted in 788kW e (86.6% of installed power). Improving the balance of the input, the dry fermentation process demonstrated biogas yields similar to wet anaerobic digestion, congruent to the energy potential of the biomasses used in the process. Furthermore, the operation of the plant required significant man labor, mainly related to loading and unloading of the anaerobic cells. Copyright © 2017 Elsevier Ltd. All rights reserved.
Nuclear Electric Magnetohydrodynamic Propulsion for Submarine
1989-05-01
develop - ment strategies for the future. The base program includes the development of the LMFBR, and HTGR to...events. Oxide fuel is -134- being retained as a backup, pending the outcome of the metal fuel development program . The design allows for a quick fuel ... HTGR plants can be developed with much higher source temperature and core power density. High efficiency and low power den- sity characteristics
Retrofitting a Geothermal Plant with Solar and Storage to Increase Power Generation
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zhu, Guangdong; McTigue, Joshua Dominic P; Turchi, Craig S
Solar hybridization using concentrating solar power (CSP) can be an effective approach to augment the power generation and power cycle efficiency of a geothermal power plant with a declining resource. Thermal storage can further increase the dispatchability of a geothermal/solar hybrid system, which is particularly valued for a national grid with high renewable penetration. In this paper, a hybrid plant design with thermal storage is proposed based on the requirements of the Coso geothermal field in China Lake, California. The objective is to increase the power production by 4 MWe. In this system, a portion of the injection brine ismore » recirculated through a heat exchanger with the solar heat transfer fluid, before being mixed with the production well brine. In the solar heating loop the brine should be heated to at least 155 degrees C to increase the net power. The solar field and storage were sized based on solar data for China Lake. Thermal storage is used to store excess power at the high-solar-irradiation hours and generate additional power during the evenings. The solar field size, the type and capacity of thermal storage and the operating temperatures are critical factors in determining the most economic hybrid system. Further investigations are required to optimize the hybrid system and evaluate its economic feasibility.« less
NASA Astrophysics Data System (ADS)
Biryuk, V. V.; Tsapkova, A. B.; Larin, E. A.; Livshiz, M. Y.; Sheludko, L. P.
2018-01-01
A set of mathematical models for calculating the reliability indexes of structurally complex multifunctional combined installations in heat and power supply systems was developed. Reliability of energy supply is considered as required condition for the creation and operation of heat and power supply systems. The optimal value of the power supply system coefficient F is based on an economic assessment of the consumers’ loss caused by the under-supply of electric power and additional system expences for the creation and operation of an emergency capacity reserve. Rationing of RI of the industrial heat supply is based on the use of concept of technological margin of safety of technological processes. The definition of rationed RI values of heat supply of communal consumers is based on the air temperature level iside the heated premises. The complex allows solving a number of practical tasks for providing reliability of heat supply for consumers. A probabilistic model is developed for calculating the reliability indexes of combined multipurpose heat and power plants in heat-and-power supply systems. The complex of models and calculation programs can be used to solve a wide range of specific tasks of optimization of schemes and parameters of combined heat and power plants and systems, as well as determining the efficiency of various redundance methods to ensure specified reliability of power supply.
Steady and transient regimes in hydropower plants
NASA Astrophysics Data System (ADS)
Gajic, A.
2013-12-01
Hydropower plant that has been in operation for about 30 years has to be reconstructed. They have already installed 12 Kaplan turbines, the largest in the world at that time. The existing CAM relationship was determined based on hydraulic model tests and checked by efficiency on-site tests. It was also tested based on turbine bearing vibrations. In order to discover vibrations and long cracks on stay vanes detailed on-site measurements were performed. Influence of the modification of the trailing edges on the dynamic stresses of the stay vanes is also shown. In order to improve power output transient regimes were analyzed, both experimentally and numerically. Reversible hydropower plant, a pioneer in Europe since it was the first Pump storage power plant constructed with the highest head pump-turbines in the world. Analyses of transient regimes discover some problems with S-shaped characteristics coupled with non-symmetrical penstock.
Phosphoric acid fuel cell 1.3 MW plant in Milan
DOE Office of Scientific and Technical Information (OSTI.GOV)
Colombo, M.; Vigano, A.
1997-07-01
At the end of the 80`s Aem, ENEA and Ansaldo Ricerche began to design and build a 1.3 MW phosphoric-acid-fuel-cell power plant for the production of electrical power and heat; this plant was built and installed in the Bicocca site, in the north-east area of Milan, where a great development is being promoted. Aem has been taking over the plant since July 1995. Its aim is to test the extensively advantages of this technology for both conversion efficiency and low environmental impact. The experimentation will have to recognize the key elements in order to plan and create the multi-megawatt plantsmore » with the phosphoric acid technology, opening the experimentation to international partners, like users, industries and Universities interested in the development and the application of these new systems of energy cogeneration.« less
Space power system utilizing Fresnel lenses for solar power and also thermal energy storage
NASA Technical Reports Server (NTRS)
Turner, R. H.
1983-01-01
A solar power plant suitable for earth orbits passing through Van Allen radiation belts is described. The solar-to-electricity conversion efficiency is estimated to be around 9 percent, and the expected power-to-weight ratio is competitive with photovoltaic arrays. The system is designed to be self-contained, to be indifferent to radiation belt exposures, store energy for periods when the orbiting system is in earth shadow (so that power generation is contant), have no moving parts and no working fluids, and be robust against micrometeorite attack. No electrical batteries are required.
Process modelling of biomass conversion to biofuels with combined heat and power.
Sharma, Abhishek; Shinde, Yogesh; Pareek, Vishnu; Zhang, Dongke
2015-12-01
A process model has been developed to study the pyrolysis of biomass to produce biofuel with heat and power generation. The gaseous and solid products were used to generate heat and electrical power, whereas the bio-oil was stored and supplied for other applications. The overall efficiency of the base case model was estimated for conversion of biomass into useable forms of bio-energy. It was found that the proposed design is not only significantly efficient but also potentially suitable for distributed operation of pyrolysis plants having centralised post processing facilities for production of other biofuels and chemicals. It was further determined that the bio-oil quality improved using a multi-stage condensation system. However, the recycling of flue gases coming from combustor instead of non-condensable gases in the pyrolyzer led to increase in the overall efficiency of the process with degradation of bio-oil quality. Copyright © 2015 Elsevier Ltd. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ghezel-Ayagh, Hossein
This topical report summarizes the results of an updated Technical & Economic Feasibility Study (T&EFS) which was conducted in Budget Period 3 of the project to evaluate the performance and cost of the Electrochemical Membrane (ECM)-based CO 2 capture system. The ECM technology is derived from commercially available inorganic membranes; the same used in FuelCell Energy’s commercial fuel cell power plants and sold under the trade name Direct FuelCell® (DFC®). The ECM stacks are utilized in the Combined Electric Power (generation) And Carbon dioxide Separation (CEPACS) systems which can be deployed as add-ons to conventional power plants (Pulverized Coal, Combinedmore » Cycle, etc.) or industrial facilities to simultaneously produce power while capturing >90% of the CO 2 from the flue gas. In this study, an ECM-based CEPACS plant was designed to capture and compress >90% of the CO 2 (for sequestration or beneficial use) from the flue gas of a reference 550 MW (nominal, net AC) Pulverized Coal (PC) Rankine Cycle (Subcritical steam) power plant. ECM performance was updated based on bench scale ECM stack test results. The system process simulations were performed to generate the CEPACS plant performance estimates. The performance assessment included estimation of the parasitic power consumption for CO 2 capture and compression, and the efficiency impact on the PC plant. While the ECM-based CEPACS system for the 550 MW PC plant captures 90% of CO 2 from the flue gas, it generates additional (net AC) power after compensating for the auxiliary power requirements of CO 2 capture and compression. An equipment list, ECM stacks packaging design, and CEPACS plant layout were developed to facilitate the economic analysis. Vendor quotes were also solicited. The economic feasibility study included estimation of CEPACS plant capital cost, cost of electricity (COE) analyses and estimation of cost per ton of CO 2 captured. The incremental COE for the ECM-based CO 2 capture is expected to meet U.S. DOE’s target of 35%. This study has indicated that CEPACS systems offer significant benefits with respect to cost, performance, water consumption and emissions to environment. The realization of these benefits will provide a single solution to carbon dioxide capture in addition to meeting the increasing demand for electricity.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ghezel-Ayagh, Hossein
This topical report summarizes the results of an updated Technical & Economic Feasibility Study (T&EFS) which was conducted in Budget Period 3 of the project to evaluate the performance and cost of the Electrochemical Membrane (ECM)-based CO2 capture system. The ECM technology is derived from commercially available inorganic membranes; the same used in FuelCell Energy’s commercial fuel cell power plants and sold under the trade name Direct FuelCell® (DFC®). The ECM stacks are utilized in the Combined Electric Power (generation) And Carbon dioxide Separation (CEPACS) systems which can be deployed as add-ons to conventional power plants (Pulverized Coal, Combined Cycle,more » etc.) or industrial facilities to simultaneously produce power while capturing >90% of the CO2 from the flue gas. In this study, an ECM-based CEPACS plant was designed to capture and compress >90% of the CO2 (for sequestration or beneficial use) from the flue gas of a reference 550 MW (nominal, net AC) Pulverized Coal (PC) Rankine Cycle (Subcritical steam) power plant. ECM performance was updated based on bench scale ECM stack test results. The system process simulations were performed to generate the CEPACS plant performance estimates. The performance assessment included estimation of the parasitic power consumption for CO2 capture and compression, and the efficiency impact on the PC plant. While the ECM-based CEPACS system for the 550 MW PC plant captures 90% of CO2 from the flue gas, it generates additional (net AC) power after compensating for the auxiliary power requirements of CO2 capture and compression. An equipment list, ECM stacks packaging design, and CEPACS plant layout were developed to facilitate the economic analysis. Vendor quotes were also solicited. The economic feasibility study included estimation of CEPACS plant capital cost, cost of electricity (COE) analyses and estimation of cost per ton of CO2 captured. The incremental COE for the ECM-based CO2 capture is expected to meet U.S. DOE’s target of 35%. This study has indicated that CEPACS systems offer significant benefits with respect to cost, performance, water consumption and emissions to environment. The realization of these benefits will provide a single solution to carbon dioxide capture in addition to meeting the increasing demand for electricity.« less
Analysis of a fuel cell on-site integrated energy system for a residential complex
NASA Technical Reports Server (NTRS)
Simons, S. N.; Maag, W. L.
1979-01-01
The energy use and costs of the on-site integrated energy system (OS/IES) which provides electric power from an on-site power plant and recovers heat that would normally be rejected to the environment is compared to a conventional system purchasing electricity from a utility and a phosphoric acid fuel cell powered system. The analysis showed that for a 500-unit apartment complex a fuel OS/IES would be about 10% more energy conservative in terms of total coal consumption than a diesel OS/IES system or a conventional system. The fuel cell OS/IES capital costs could be 30 to 55% greater than the diesel OS/IES capital costs for the same life cycle costs. The life cycle cost of a fuel cell OS/IES would be lower than that for a conventional system as long as the cost of electricity is greater than $0.05 to $0.065/kWh. An analysis of several parametric combinations of fuel cell power plant and state-of-art energy recovery systems and annual fuel requirement calculations for four locations were made. It was shown that OS/IES component choices are a major factor in fuel consumption, with the least efficient system using 25% more fuel than the most efficient. Central air conditioning and heat pumps result in minimum fuel consumption while individual air conditioning units increase it, and in general the fuel cell of highest electrical efficiency has the lowest fuel consumption.
NASA Astrophysics Data System (ADS)
Munts, V. A.; Volkova, Yu. V.; Plotnikov, N. S.; Dubinin, A. M.; Tuponogov, V. G.; Chernishev, V. A.
2015-11-01
The results from tests of a 5 kW power plant on solid-oxide fuel cells (SOFCs), in which natural gas is used as fuel, are presented. The installation's process circuit, the test procedure, and the analysis of the obtained results are described. The characteristics of the power plant developed by the Ural Industrial Company are investigated in four steady-state modes of its operation: with the SOFC nominal power capacity utilized by 40% (2 kW), 60% (3 kW), 90% (4.5 kW) and 110% (5.4 kW) (the peaking mode). The electrical and thermodynamic efficiencies are calculated for all operating modes, and the most efficient mode, in which the electrical efficiency reached almost 70%, is determined. The air excess coefficient and heat loss with flue gases q 2 are determined, and it is revealed that the heat loss q 5 decreases from 40 to 25% with increasing the load. Thermal balances are drawn up for the following components of the system the reformer, the SOFC battery, the catalytic burner for afterburning anode gases, the heat exchanger for heating the cathode air and the mixture of natural gas and steam, and the actual fuel utilization rates in the electrochemical generator are calculated. An equation for the resulting natural gas steam reforming reaction was obtained based on the results from calculating the equilibrium composition of reforming products for the achieved temperatures at the reformer outlet t 3.
Recent Developments in Niobium Containing Austenitic Stainless Steels for Thermal Power Plants
NASA Astrophysics Data System (ADS)
de Oliveira, Mariana Perez; Zhang, Wei; Yu, Hongyao; Bao, Hansheng; Xie, Xishan
The challenge of growing continuously in a sustainable way is the main driver to improve efficiency in the use of natural resources. The increasing demand for energy has made thermal power based countries to set audacious programs to increase efficiency of thermal power generation. In China, coal-burning accounts nowadays for approximately 65% of the total primary energy supply being responsible for around 25% of the countries' CO2 emission, this coal-based energy supply scenario is believed to continue until 2020. Therefore, the country has invested strongly in the last years in the construction of more efficient power plants. To attend higher operating temperatures and steam pressures, the application of higher performance materials is mandatory, presenting improved mechanical resistance — to stand the higher pressures applied — and having sufficient high temperature and corrosion resistance with the best cost-benefit relation possible. The present work addresses some research developments made in niobium containing austenitic stainless steels for super heaters and re-heater tubes in the past years as a joint effort between industry and academia to understand mechanisms and optimize the steel chemical composition, improving its performance. Niobium role has been studied in detail in heat resistant stainless steels TP347H, Super 304 and HR3C, a summary of such studies is presented in this paper. Niobium improves high temperature properties as it precipitates as nano-size MX and NbCrN, well dispersed in the matrix, hindering dislocation movement, increasing precipitation strengthening and creep resistance.
NASA Astrophysics Data System (ADS)
Pochylý, F.; Haluza, M.; Fialová, S.; Dobšáková, L.; Volkov, A. V.; Parygin, A. G.; Naumov, A. V.; Vikhlyantsev, A. A.; Druzhinin, A. A.
2017-11-01
The results of independent research implemented by the teams of authors representing the Brno University of technology (Czech Republic) and Moscow Power Engineering Institute National Research University (Russia) are presented and compared. The possibilities for improving the energy efficiency of slow-speed centrifugal pumps (with a specific speed coefficient n s < 80) widely used in power engineering—in thermal power stations, in heat electric-power stations, in nuclear power plants, and in boiler rooms—were investigated. These are supply pumps, condensate pumps, precharge pumps, etc. The pumps with such values of n s are widely used in some technological cycles of oil-and-gas and chemical industries too. The research was focused on achieving the shape of the pump efficiency characteristics providing a significant extension of its effective working zone and increasing its integrated efficiency. The results were obtained based on new approaches to the formation of a blading system of an impeller of a slow-speed centrifugal pump different from the traditional blading system. The analytical dependences illustrating the influence of individual geometry of a blading system on the efficiency were presented. The possibilities of purposeful changing of its structure were demonstrated. It was experimentally confirmed that use of the innovative blading system makes it possible to increase the pump efficiency by 1-4% (in the experiments for the pumps with n s = 33 and 55) and to extend its efficient working zone approximately by 15-20% (in the experiment for the pumps with n s = 33 and 66). The latter is especially important for the supply pumps of NPP power units. The experimental results for all investigated pumps are presented in comparison with the characteristics of the efficiency provided by the blading systems designed by traditional methods.
Co-Simulation for Advanced Process Design and Optimization
DOE Office of Scientific and Technical Information (OSTI.GOV)
Stephen E. Zitney
2009-01-01
Meeting the increasing demand for clean, affordable, and secure energy is arguably the most important challenge facing the world today. Fossil fuels can play a central role in a portfolio of carbon-neutral energy options provided CO{sub 2} emissions can be dramatically reduced by capturing CO{sub 2} and storing it safely and effectively. Fossil energy industry faces the challenge of meeting aggressive design goals for next-generation power plants with CCS. Process designs will involve large, highly-integrated, and multipurpose systems with advanced equipment items with complex geometries and multiphysics. APECS is enabling software to facilitate effective integration, solution, and analysis of high-fidelitymore » process/equipment (CFD) co-simulations. APECS helps to optimize fluid flow and related phenomena that impact overall power plant performance. APECS offers many advanced capabilities including ROMs, design optimization, parallel execution, stochastic analysis, and virtual plant co-simulations. NETL and its collaborative R&D partners are using APECS to reduce the time, cost, and technical risk of developing high-efficiency, zero-emission power plants with CCS.« less
Thermoelectric energy conversion with solid electrolytes
DOE Office of Scientific and Technical Information (OSTI.GOV)
Cole, T.
1983-09-02
The alkali metal thermoelectric converter (AMTEC) is a device for the direct conversion of heat to electrical energy. The sodium ion conductor beta''-alumina is used to form a high-temperature regenerative concentration cell for elemental sodium. An AMTEC of mature design should have an efficiency of 20 to 40%, a power density of 0.5 kilowatt per kilogram or more, no moving parts, low maintenance requirements, high durability, and efficiency independent of size. It should be usable with high-temperature combustion, nuclear, or solar heat sources. Experiments have demonstrated the feasibility of the AMTEC and confirmed the theoretical analysis of the device. Amore » wide range of applications from aerospace power to utility power plants appears possible.« less
Coping with carbon: a near-term strategy to limit carbon dioxide emissions from power stations.
Breeze, Paul
2008-11-13
Burning coal to generate electricity is one of the key sources of atmospheric carbon dioxide emissions; so, targeting coal-fired power plants offers one of the easiest ways of reducing global carbon emissions. Given that the world's largest economies all rely heavily on coal for electricity production, eliminating coal combustion is not an option. Indeed, coal consumption is likely to increase over the next 20-30 years. However, the introduction of more efficient steam cycles will improve the emission performance of these plants over the short term. To achieve a reduction in carbon emissions from coal-fired plant, however, it will be necessary to develop and introduce carbon capture and sequestration technologies. Given adequate investment, these technologies should be capable of commercial development by ca 2020.
Yttria-stabilized zirconia solid oxide electrolyte fuel cells: Monolithic solid oxide fuel cells
NASA Astrophysics Data System (ADS)
1990-10-01
The monolithic solid oxide fuel cell (MSOFC) is currently under development for a variety of applications including coal-based power generation. The MSOFC is a design concept that places the thin components of a solid oxide fuel cell in lightweight, compact, corrugated structure, and so achieves high efficiency and excellent performance simultaneously with high power density. The MSOFC can be integrated with coal gasification plants and is expected to have high overall efficiency in the conversion of the chemical energy of coal to electrical energy. This report describes work aimed at: (1) assessing manufacturing costs for the MSOFC and system costs for a coal-based plant; (2) modifying electrodes and electrode/electrolyte interfaces to improve the electrochemical performance of the MSOFC; and (3) testing the performance of the MSOFC on hydrogen and simulated coal gas. Manufacturing costs for both the coflow and crossflow MSOFC's were assessed based on the fabrication flow charts developed by direct scaleup of tape calendering and other laboratory processes. Integrated coal-based MSOFC systems were investigated to determine capital costs and costs of electricity. Design criteria were established for a coal-fueled 200-Mw power plant. Four plant arrangements were evaluated, and plant performance was analyzed. Interfacial modification involved modification of electrodes and electrode/electrolyte interfaces to improve the MSOFC electrochemical performance. Work in the cathode and cathode/electrolyte interface was concentrated on modification of electrode porosity, electrode morphology, electrode material, and interfacial bonding. Modifications of the anode and anode/electrolyte interface included the use of additives and improvement of nickel distribution. Single cells have been tested for their electrochemical performance. Performance data were typically obtained with humidified H2 or simulated coal gas and air or oxygen.
Evaluation of the environmental sustainability of different waste-to-energy plant configurations.
Lombardi, Lidia; Carnevale, Ennio A
2018-03-01
Residual municipal solid waste (MSW) has an average lower heating value higher than 10GJ/Mg in the EU, and can be recovered in modern Waste-to-Energy (WtE) plants, producing combined heat and power (CHP) and reaching high levels of energy recovery. CHP is pinpointed as the best technique for energy recovery from waste. However, in some cases, heat recovery is not technically feasible - due to the absence of a thermal user (industrial plant or district heating) in the vicinity of the WtE plant - and power production remains the sole possibility. In these cases, there are some challenges involved in increasing the energy performance as much as possible. High energy recovery efficiency values are very important for the environmental sustainability of WtE plants. The more electricity and heat is produced, the better the saving of natural resources that can be achieved. Within this frame, the aim of this work is to carry out an environmental assessment, through Life Cycle Assessment, of an MSW WtE plant, considering different sizes and operated in different ways, from power production only to full cogeneration. The main assumption is that the electric conversion efficiency increases as the plant size increases, introducing technical improvements thanks to the economies of scale. Impact assessment results were calculated using ReCiPe 2008 methods. The climate change indicator is positive when the WtE plant is operated in power production only mode, with values decreasing for the increasing size. Values for the climate change are negative when cogeneration is applied, requiring increasing cogeneration ratios for decreasing size. Similarly, the fossil fuel depletion indicator benefits from increase of both the plant size and the cogeneration rate, but it is always negative, meaning that the residual MSW burning with energy recovery always provides a saving of fossil primary energy. Other indicator values are in general negative and are also beneficially affected by increasing the plant size, but they worsen when increasing the cogeneration rate. The remaining indicators - i.e. human toxicity and terrestrial ecotoxicity - always have positive values, which decrease for increasing plant size and increase as the cogeneration rate increases. However, the local context should be evaluated carefully with reference to the type of electricity which is substituted and in view of a future massive production of renewable electricity, because conclusions change accordingly. Finally, it was evaluated that the inclusion of bottom ash recovery - instead of landfilling - can significantly improve the values of several impact assessment indicators. Copyright © 2017 Elsevier Ltd. All rights reserved.
World Geothermal Congress WGC-2015
NASA Astrophysics Data System (ADS)
Tomarov, G. V.; Shipkov, A. A.
2016-08-01
This article discusses materials and results of the World Geothermal Congress that was held in Melbourne (Australia) from April 19 to April 25, 2015. Information on the extent and technological features of utilization of geothermal resources for heat supply and power production, as well as in other economic areas, is given. A stable growth in the capacity and number of geothermal power systems that is determined by ecological cleanliness, economic efficiency, and the highest (among renewable energy sources) indicators of installed capacity utilization is shown. It was noted that combined schemes of geothermal power plants (GPPs), such as turbine units of different type (binary units, units with one or two separation pressures, etc.), have become more frequently used to increase the efficiency of utilization of geothermal heat carrier. Actual data determining room heating systems with the total worldwide capacity of nearly 50000 MW thermal (MWt) as the most currently significant segment of consumption of geothermal waters are given. In addition, geothermal resources are also utilized in soil pumps, balneological and sports basins, greenhouse complexes, and other manufactures. It was noted that geological studies were carried out in more than 40 countries, with the development of methods of simulation of tanks for the existing and new geothermal fields. Trends of development and the role of geothermal power engineering in the energy supply of many countries are shown. It was shown that prospects for the development of geothermal power generation are significantly associated with utilization of low-temperature geothermal sources in binary power generating units, as well as with the increase in installed capacity of operating geothermal power plants (GPPs) without drilling additional wells, i.e., by using waste geothermal heat carrier in binary-cycle or combined-cycle power plants. The article provides data on a pilot binary power unit at Pauzhetka GPP and on a promising Russian geothermal project to increase the installed capacity of Mutnovsk GPP (whose current capacity is 50.0 (2 × 25.0) MW of electric power) by 25% by constructing a combined binary-cycle power generating unit on the basis of waste separate utilization.
Increasing Efficiency by Maximizing Electrical Output
2016-07-27
in a few limited areas, one being a geothermal flash plant at Naval Air Weapons Station China Lake. But, there are few other heat to electricity...generation sources (but, closest to geothermal because of the lack of combustion and the maintenance issues involved with combustion). [11] Clearly, a...of Energy Resources Technology, March 2009, Vol. 131 [4] “The Chena Hot Springs 400kW Geothermal Power Plant: Experience Gained During the First
Detection and Sizing of Defects in Structural Components of a Nuclear Power Plant by ECT
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chen Zhenmao; Miya, Kenzo
2005-04-09
In this paper, progress of ECT technique for inspection of stress corrosion cracks in a structural component of a nuclear power plant is reported. Access and scanning vehicle (robot), advanced probes for SG tube inspection, development and evaluation of new probes for welding joint, and ECT based crack sizing technique are described respectively. Based on these new techniques, it is clarified that ECT can play as a supplement of UT for the welding zone inspection. It is also proved in this work that new ECT sensors are efficient even for a stainless plate as thick as 15mm.
Efficient, full-spectrum, long-lived, non-toxic microwave lamp for plant growth
DOE Office of Scientific and Technical Information (OSTI.GOV)
MacLennan, D.A.; Turner, B.P.; Dolan, J.T.
1994-12-31
Fusion Systems Corporation has developed a mercury-free, low infra-red, efficient microwave lamp using a benign sulfur based fill optimized for visible light. Our literature search and discussions with researchers directed us to enhance the bulbs red output. We have demonstrated a photosynthetic efficacy of over 2 micro-moles per microwave joule which corresponds to over 1.3 micro-moles per joule at the power main. Recent work has shown we can make additional increases in overall system efficiency. During the next two years, we expect to demonstrate a system capable of producing more than 1.5 micro-moles/joule measured at the power main with significantlymore » less IR than alternative lamp systems.« less
Thermal Storage Applications Workshop. Volume 1: Plenary Session Analysis
NASA Technical Reports Server (NTRS)
1979-01-01
The importance of the development of inexpensive and efficient thermal and thermochemical energy storage technology to the solar power program is discussed in a summary of workship discussions held to exchange information and plan for future systems. Topics covered include storage in central power applications such as the 10 MW-e demonstration pilot receiver to be constructed in Barstow, California; storage for small dispersed systems, and problems associated with the development of storage systems for solar power plants interfacing with utility systems.
DOE Office of Scientific and Technical Information (OSTI.GOV)
NONE
Topics covered include: energy security; clean energy and low carbon; energy for growth and poverty reduction in Africa; financing of energy efficiency; SMEs for decentralised energy service provision; potential for biofuels in developing countries; clean energy and sustainable development; clean energy finance and private equity funds; power generation and low carbon technologies; beyond traditional finance; rehabilitation and emission control in thermal power plants; and carbon finance. The presentations are mainly in ppt (Power Point) or pdf (Acrobat) format. Some videos of the conference are also available on the website.
Dwivedi, S; Srivastava, S; Mishra, S; Dixit, B; Kumar, A; Tripathi, R D
2008-10-30
The present investigation was carried out to screen native plants growing in fly-ash (FA) contaminated areas near National Thermal Power Corporation, Tanda, Uttar Pradesh, India with a view to using them for the eco-restoration of the area. A total number of 17 plants (9 aquatic, 6 terrestrial and 2 algal species) were collected and screened for heavy metal (Fe, Zn, Cu, Mo, B, Si, Al, Cr, Pb, Cd, Hg and As) accumulation. Differential accumulation of various heavy metals by different species of plants was observed. Hydrilla verticillata was found to be the most efficient metal accumulator among 9 aquatic plants, Eclipta alba among 6 terrestrial plants and Phormedium papyraceum between 2 algal species. In general, the maximum levels of most metals were found in terrestrial plants while the lowest in algal species. However, translocation of the metals from root to shoot was found to be higher in aquatic plants than terrestrial ones. These results suggest that various aquatic, terrestrial and algal species of plants may be used in a synergistic way to remediate and restore the FA contaminated areas.
UTC Power/Delphi SECA CBS Final Report
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gorman, Michael; Kerr, Rich
2013-04-04
The subject report summarizes the results of solid oxide fuel cell development conducted by UTC Power in conjunction with Delphi Automotive Systems under a cost-share program with from October 2008 through March of 2013. Over that period Delphi Automotive Systems developed a nearly four times larger area solid oxide fuel cell stack capable of operating on pre-reformed natural gas and simulated coal gas with durability demonstrated to 5,000 hours and projected to exceed 10,000 hours. The new stack design was scaled to 40-cell stacks with power output in excess of 6.25kW. Delphi also made significant strides in improving the manufacturability,more » yield and production cost of these solid oxide fuel cells over the course of the program. Concurrently, UTC Power developed a conceptual design for a 120 MW Integrated Gasification Fuel Cell (IGFC) operating on coal syngas with as high as 57% Higher Heating Value (HHV) efficiency as a measure of the feasibility of the technology. Subsequently a 400 kW on-site system preliminary design with 55% Lower Heating Value (LHV) efficiency operating on natural gas was down-selected from eighteen candidate designs. That design was used as the basis for a 25kW breadboard power plant incorporating four Delphi cell stacks that was tested on natural gas before the program was discontinued due to the sale of UTC Power in early 2013. Though the program was cut short of the endurance target of 3,000 hours, many aspects of the technology were proven including: large-area, repeatable cell manufacture, cell stack operation on simulated coal gas and natural gas and integrated power plant operation on natural gas. The potential of the technology for high efficiency stationary electric power generation is clear. Acceptable production costs, durability, and reliability in real world environments are the remaining challenges to commercialization.« less
NASA Technical Reports Server (NTRS)
Wolfe, R. W.
1976-01-01
A parametric analysis was made of three types of advanced steam power plants that use coal in order to have a comparison of the cost of electricity produced by them a wide range of primary performance variables. Increasing the temperature and pressure of the steam above current industry levels resulted in increased energy costs because the cost of capital increased more than the fuel cost decreased. While the three plant types produced comparable energy cost levels, the pressurized fluidized bed boiler plant produced the lowest energy cost by the small margin of 0.69 mills/MJ (2.5 mills/kWh). It is recommended that this plant be designed in greater detail to determine its cost and performance more accurately than was possible in a broad parametric study and to ascertain problem areas which will require development effort. Also considered are pollution control measures such as scrubbers and separates for particulate emissions from stack gases.
Streamlining and Standardizing Due Diligence to Ensure Quality of PV Power Plants
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kurtz, Sarah
Those investing in PV power plants would like to have confidence that the plants will provide the anticipated return on investment. While due diligence is capably performed by independent engineers today, as PV systems mature, there will be benefit in standardization and streamlining of this process. The IECRE has defined technical information that is needed as a basis for each transaction step such as approving a design to begin construction, documenting readiness to operate, quantifying performance after a year of operation, and assessing the health of the plant in preparation for sale of the plant. The technical requirements have beenmore » defined by IEC Technical Committee 82 and have been designed to be both effective and efficient in completing the assessments. This workshop will describe these new tools that are now available to the community and will include a panel/audience discussion about how and when they can be most effectively used.« less
Efficient air pollution regulation of coal-fired power in China
NASA Astrophysics Data System (ADS)
Feng, Therese
This dissertation evaluates monetary external costs of electricity generation in the People's Republic of China and implications for efficient pollution control policy. It presents an integrated assessment of environmental damages of air emissions of a representative new coal-fired plant in urban areas of north and south China. The simulation evaluates the nature and magnitude of damages in China, transboundary effects in Japan and Korea, and global greenhouse gas warming impacts. The valuation is used to identify efficient abatement policy for Chinese plants over time; evaluate benefits of differentiated policies; and consider the importance of dynamic policy. Potential annual damages of operating a 600-MW power plant without controls in China today would be 43-45 million (U.S. 1995). Annual local damages of 37-40 million far exceed transboundary or greenhouse gas damages (1.4 million and $4.6 million respectively). The largest component of damages is the risk of human mortality and chronic morbidity from long-term exposure to fine particles. Efficient pollution control minimizes the sum of abatement costs and residual unabated damages. Because monetary damages reflect sufferers' willingness to pay to avoid environmental risks, the choice of efficient controls is fundamentally tied to societal values and preferences. The optimal path for Chinese abatement moves from modest dispersion measures at present to combined dispersion and emission controls approaching those of current-day United States, by 2050. The inclusion of transboundary and greenhouse damages does not substantively alter local policies. Welfare benefits are gained by differentiating abatement policy by pollutant, meteorological parameters, and by population density. An analysis of optimal one-time investment in abatement for a plant in a growing economy suggests that some investment is optimal at all incomes but no single level of abatement is suitable for all economies. Forward-looking policy anticipates higher future values for environmental services and provides distinct welfare advantages over time compared to myopic or static policies-such as the imposition of developed country standards-especially if aggregate capacity growth is considered.
Efficiency mark of the two-product power complex of nuclear power plant
NASA Astrophysics Data System (ADS)
Khrustalev, V. A.; Suchkov, V. M.
2017-11-01
The article discusses the combining nuclear power plants (NPP) with pressurized water reactors and distillation-desalination plants (DDP), their joint mode of operation during periods of coating failures of the electric power load graphs and thermo-economical efficiency. Along with the release of heat and generation of electric energy a desalination complex with the nuclear power plant produces distillate. Part of the selected steam “irretrievably lost” with a mix of condensation of this vapor in a desalination machine with a flow of water for distillation. It means that this steam transforms into condition of acquired product - distillate. The article presents technical solutions for the return of the working fluid for turbine К-1000-60/1500-2 и К-1200-6,8/50, as well as permissible part of low pressure regime according to the number of desalination units for each turbine. Patent for the proposed two-product energy complex, obtained by Gagarin State Technical University is analyzed. The energy complex has such system advantages as increasing the capacity factor of a nuclear reactor and also allows to solve the problem of shortage of fresh water. Thermo-economics effectiveness of this complex is determined by introducing a factor-“thermo-economic index”. During analyzing of the results of the calculations of a thermo-economic index we can see a strong influence of the cost factor of the distillate on the market. Then higher participation of the desalination plant in coverage of the failures of the graphs of the electric loading then smaller the payback period of the NPP. It is manifested more clearly, as it’s shown in the article, when pricing options depend on time of day and the configuration of the daily electric load diagram. In the geographical locations of the NPPs with PWR the Russian performance in a number of regions with low freshwater resources and weak internal electrical connections combined with DDP might be one of the ways to improve the competitiveness of NPPs, especially for foreign coastal areas.
Tampa Electric Company Polk Power Station IGCC project: Project status
DOE Office of Scientific and Technical Information (OSTI.GOV)
McDaniel, J.E.; Carlson, M.R.; Hurd, R.
1997-12-31
The Tampa Electric Company Polk Power Station is a nominal 250 MW (net) Integrated Gasification Combined Cycle (IGCC) power plant located to the southeast of Tampa, Florida in Polk County, Florida. This project is being partially funded under the Department of Energy`s Clean Coal Technology Program pursuant to a Round II award. The Polk Power Station uses oxygen-blown, entrained-flow IGCC technology licensed from Texaco Development Corporation to demonstrate significant reductions of SO{sub 2} and NO{sub x} emissions when compared to existing and future conventional coal-fired power plants. In addition, this project demonstrates the technical feasibility of commercial scale IGCC andmore » Hot Gas Clean Up (HGCU) technology. The Polk Power Station achieved ``first fire`` of the gasification system on schedule in mid-July, 1996. Since that time, significant advances have occurred in the operation of the entire IGCC train. This paper addresses the operating experiences which occurred in the start-up and shakedown phase of the plant. Also, with the plant being declared in commercial operation as of September 30, 1996, the paper discusses the challenges encountered in the early phases of commercial operation. Finally, the future plans for improving the reliability and efficiency of the Unit in the first quarter of 1997 and beyond, as well as plans for future alternate fuel test burns, are detailed. The presentation features an up-to-the-minute update on actual performance parameters achieved by the Polk Power Station. These parameters include overall Unit capacity, heat rate, and availability. In addition, the current status of the start-up activities for the HGCU portion of the plant is discussed.« less
Proton exchange membrane fuel cell technology for transportation applications
DOE Office of Scientific and Technical Information (OSTI.GOV)
Swathirajan, S.
1996-04-01
Proton Exchange Membrane (PEM) fuel cells are extremely promising as future power plants in the transportation sector to achieve an increase in energy efficiency and eliminate environmental pollution due to vehicles. GM is currently involved in a multiphase program with the US Department of Energy for developing a proof-of-concept hybrid vehicle based on a PEM fuel cell power plant and a methanol fuel processor. Other participants in the program are Los Alamos National Labs, Dow Chemical Co., Ballard Power Systems and DuPont Co., In the just completed phase 1 of the program, a 10 kW PEM fuel cell power plantmore » was built and tested to demonstrate the feasibility of integrating a methanol fuel processor with a PEM fuel cell stack. However, the fuel cell power plant must overcome stiff technical and economic challenges before it can be commercialized for light duty vehicle applications. Progress achieved in phase I on the use of monolithic catalyst reactors in the fuel processor, managing CO impurity in the fuel cell stack, low-cost electrode-membrane assembles, and on the integration of the fuel processor with a Ballard PEM fuel cell stack will be presented.« less
Foxtail Mosaic Virus-Induced Gene Silencing in Monocot Plants1[OPEN
Liu, Na; Xie, Ke; Jia, Qi; Zhao, Jinping; Chen, Tianyuan; Li, Huangai; Wei, Xiang; Diao, Xianmin; Hong, Yiguo
2016-01-01
Virus-induced gene silencing (VIGS) is a powerful technique to study gene function in plants. However, very few VIGS vectors are available for monocot plants. Here we report that Foxtail mosaic virus (FoMV) can be engineered as an effective VIGS system to induce efficient silencing of endogenous genes in monocot plants including barley (Hordeum vulgare L.), wheat (Triticum aestivum) and foxtail millet (Setaria italica). This is evidenced by FoMV-based silencing of phytoene desaturase (PDS) and magnesium chelatase in barley, of PDS and Cloroplastos alterados1 in foxtail millet and wheat, and of an additional gene IspH in foxtail millet. Silencing of these genes resulted in photobleached or chlorosis phenotypes in barley, wheat, and foxtail millet. Furthermore, our FoMV-based gene silencing is the first VIGS system reported for foxtail millet, an important C4 model plant. It may provide an efficient toolbox for high-throughput functional genomics in economically important monocot crops. PMID:27225900
DOE Office of Scientific and Technical Information (OSTI.GOV)
O'Brien, Kevin C.
The work summarized in this report is the first step towards a project that will re-train and create jobs for personnel in the coal industry and continue regional economic development to benefit regions impacted by previous downturns. The larger project is aimed at capturing ~300 tons/day (272 metric tonnes/day) CO 2 at a 90% capture rate from existing coal- fired boilers at the Abbott Power Plant on the campus of University of Illinois (UI). It will employ the Linde-BASF novel amine-based advanced CO 2 capture technology, which has already shown the potential to be cost-effective, energy efficient and compact atmore » the 0.5-1.5 MWe pilot scales. The overall objective of the project is to design and install a scaled-up system of nominal 15 MWe size, integrate it with the Abbott Power Plant flue gas, steam and other utility systems, and demonstrate the viability of continuous operation under realistic conditions with high efficiency and capacity. The project will also begin to build a workforce that understands how to operate and maintain the capture plants by including students from regional community colleges and universities in the operation and evaluation of the capture system. This project will also lay the groundwork for follow-on projects that pilot utilization of the captured CO 2 from coal-fired power plants. The net impact will be to demonstrate a replicable means to (1) use a standardized procedure to evaluate power plants for their ability to be retrofitted with a pilot capture unit; (2) design and construct reliable capture systems based on the Linde-BASF technology; (3) operate and maintain these systems; (4) implement training programs with local community colleges and universities to establish a workforce to operate and maintain the systems; and (5) prepare to evaluate at the large pilot scale level various methods to utilize the resulting captured CO 2. Towards the larger project goal, the UI-led team, together with Linde, has completed a preliminary design for the carbon capture pilot plant with basic engineering and cost estimates, established permitting needs, identified approaches to address Environmental, Health, and Safety concerns related to pilot plant installation and operation, developed approaches for long-term use of the captured carbon, and established strategies for workforce development and job creation that will re-train coal operators to operate carbon capture plants. This report describes Phase I accomplishments and demonstrates that the project team is well-prepared for full implementation of Phase 2, to design, build, and operate the carbon capture pilot plant.« less
USE OF COAL DRYING TO REDUCE WATER CONSUMED IN PULVERIZED COAL POWER PLANTS
DOE Office of Scientific and Technical Information (OSTI.GOV)
Edward Levy; Nenad Sarunac; Harun Bilirgen
2005-04-01
This is the ninth Quarterly Report for this project. The background and technical justification for the project are described, including potential benefits of reducing fuel moisture using power plant waste heat, prior to firing the coal in a pulverized coal boiler. During this last Quarter, comparative analyses were performed for lignite and PRB coals to determine how unit performance varies with coal product moisture. Results are given showing how the coal product moisture level and coal rank affect parameters such as boiler efficiency, station service power needed for fans and pulverizers and net unit heat rate. Results are also givenmore » for the effects of coal drying on cooling tower makeup water and comparisons are made between makeup water savings for various times of the year.« less
Effects of California's Climate Policy in Facilitating CCUS
DOE Office of Scientific and Technical Information (OSTI.GOV)
Burton, Elizabeth
California is at the forefront of addressing the challenges involved in redesigning its energy infrastructure to meet 2050 GHG reduction goals, but CCUS commercialization lags in California as it does elsewhere. It is unclear why this is the case given the state’s forefront position in aggressive climate change policy. The intent of this paper is to examine the factors that may explain why CCUS has not advanced as rapidly as other GHG emissions mitigation technologies in California and identify ways by which CCUS commercialization may be advanced in the context of California’s future energy infrastructure. CCUS has application to reducemore » GHG emissions from the power, industrial and transportation sectors in the state. Efficiency, use of renewable energy or nuclear generation to replace fossil fuels, use of lower or no-net-carbon feedstocks (such as biomass), and use of CCUS on fossil fuel generation are the main options, but California has fewer options for making the deep cuts in CO 2 emissions within the electricity sector to meet 2050 goals. California is already the most efficient of all 50 states as measured by electricity use per capita, and, while further efficiency measures can reduce per capita consumption, increasing population is still driving electricity demand upwards. A 1976 law prevents building any new nuclear plants until a federal high-level nuclear waste repository is approved. Most all in-state electricity generation already comes from natural gas; although California does plan to eliminate electricity imports from out-of-state coal-fired generation. Thus, the two options with greatest potential to reduce in-state power sector CO 2 emissions are replacing fossil with renewable generation or employing CCUS on natural gas power plants. Although some scenarios call on California to transition its electricity sector to 100 percent renewables, it is unclear how practical this approach is given the intermittency of renewable generation, mismatches between peak generation times and demand times, and the rate of progress in developing technologies for large-scale power storage. Vehicles must be electrified or move to biofuels or zero-carbon fuels in order to decarbonize the transportation sector. These options transfer the carbon footprint of transportation to other sectors: the power sector in the case of electric vehicles and the industrial and agricultural sectors in the case of biofuels or zero-carbon fuels. Thus, the underlying presumption to achieve overall carbon reductions is that the electricity used by vehicles does not raise the carbon emissions of the power sector: biofuel feedstock growth, harvest, and processing uses low carbon energy or production of fuels from fossil feedstocks employs CCUS. This results in future transportation sector energy derived solely from renewables, biomass, or fossil fuel point sources utilizing CCUS. In the industrial sector, the largest contributors to GHG emissions are transportation fuel refineries and cement plants. Emissions from refineries come from on-site power generation and hydrogen plants; while fuel mixes can be changed to reduce the GHG emissions from processing and renewable sources can be used to generate power, total decarbonization requires use of CCUS. Similarly, for cement plants, power generation may use carbon-free feedstocks instead of fossil fuels, but CO 2 emissions associated with the manufacture of cement products must be dealt with through CCUS. Of course, another option for these facilities is the purchase of offsets to create a zero-emissions plant.« less
Effects of California's Climate Policy in Facilitating CCUS
Burton, Elizabeth
2014-12-31
California is at the forefront of addressing the challenges involved in redesigning its energy infrastructure to meet 2050 GHG reduction goals, but CCUS commercialization lags in California as it does elsewhere. It is unclear why this is the case given the state’s forefront position in aggressive climate change policy. The intent of this paper is to examine the factors that may explain why CCUS has not advanced as rapidly as other GHG emissions mitigation technologies in California and identify ways by which CCUS commercialization may be advanced in the context of California’s future energy infrastructure. CCUS has application to reducemore » GHG emissions from the power, industrial and transportation sectors in the state. Efficiency, use of renewable energy or nuclear generation to replace fossil fuels, use of lower or no-net-carbon feedstocks (such as biomass), and use of CCUS on fossil fuel generation are the main options, but California has fewer options for making the deep cuts in CO 2 emissions within the electricity sector to meet 2050 goals. California is already the most efficient of all 50 states as measured by electricity use per capita, and, while further efficiency measures can reduce per capita consumption, increasing population is still driving electricity demand upwards. A 1976 law prevents building any new nuclear plants until a federal high-level nuclear waste repository is approved. Most all in-state electricity generation already comes from natural gas; although California does plan to eliminate electricity imports from out-of-state coal-fired generation. Thus, the two options with greatest potential to reduce in-state power sector CO 2 emissions are replacing fossil with renewable generation or employing CCUS on natural gas power plants. Although some scenarios call on California to transition its electricity sector to 100 percent renewables, it is unclear how practical this approach is given the intermittency of renewable generation, mismatches between peak generation times and demand times, and the rate of progress in developing technologies for large-scale power storage. Vehicles must be electrified or move to biofuels or zero-carbon fuels in order to decarbonize the transportation sector. These options transfer the carbon footprint of transportation to other sectors: the power sector in the case of electric vehicles and the industrial and agricultural sectors in the case of biofuels or zero-carbon fuels. Thus, the underlying presumption to achieve overall carbon reductions is that the electricity used by vehicles does not raise the carbon emissions of the power sector: biofuel feedstock growth, harvest, and processing uses low carbon energy or production of fuels from fossil feedstocks employs CCUS. This results in future transportation sector energy derived solely from renewables, biomass, or fossil fuel point sources utilizing CCUS. In the industrial sector, the largest contributors to GHG emissions are transportation fuel refineries and cement plants. Emissions from refineries come from on-site power generation and hydrogen plants; while fuel mixes can be changed to reduce the GHG emissions from processing and renewable sources can be used to generate power, total decarbonization requires use of CCUS. Similarly, for cement plants, power generation may use carbon-free feedstocks instead of fossil fuels, but CO 2 emissions associated with the manufacture of cement products must be dealt with through CCUS. Of course, another option for these facilities is the purchase of offsets to create a zero-emissions plant.« less
NASA Astrophysics Data System (ADS)
Roche, M.
A solar thermal power plant using fused salt as the heat transfer fluid for steam power generation is analyzed for the feasibility of economic operation. The salt is also stored in a tank reservoir for maintaining the primary heat loop at temperatures high enough for the salts to remain liquid, and also to provide reserve power for the steam generator. Initial studies were with eutectic (hitec) salt comprising Na, KOH, and nitrites melting at 146 C, and further studies were performed employing draw salt, which has no nitrite, is more stable at high temperature, and melts at 225 C. The use of draw salt was found to allow a 5 percent reduction in storage capacity. Further examinations of the effects of the hitec salts on corrosion and composition degradation at high temperatures are indicated. The molten salt system is projected to offer an efficiency of 26 percent.
The Satellite Nuclear Power Station - An option for future power generation.
NASA Technical Reports Server (NTRS)
Williams, J. R.; Clement, J. D.
1973-01-01
A new concept in nuclear power generation is being explored which essentially eliminates major objections to nuclear power. The Satellite Nuclear Power Station, remotely operated in synchronous orbit, would transmit power safely to the ground by a microwave beam. Fuel reprocessing would take place in space and no radioactive materials would ever be returned to earth. Even the worst possible accident to such a plant should have negligible effect on the earth. An exploratory study of a satellite nuclear power station to provide 10,000 MWe to the earth has shown that the system could weigh about 20 million pounds and cost less than $1000/KWe. An advanced breeder reactor operating with an MHD power cycle could achieve an efficiency of about 50% with a 1100 K radiator temperature. If a hydrogen moderated gas core reactor is used, its breeding ratio of 1.10 would result in a fuel doubling time of a few years. A rotating fluidized bed or NERVA type reactor might also be used. The efficiency of power transmission from synchronous orbit would range from 70% to 80%.
Násner, Albany Milena Lozano; Lora, Electo Eduardo Silva; Palacio, José Carlos Escobar; Rocha, Mateus Henrique; Restrepo, Julian Camilo; Venturini, Osvaldo José; Ratner, Albert
2017-11-01
This work deals with the development of a Refuse Derived Fuel (RDF) gasification pilot plant using air as a gasification agent. A downdraft fixed bed reactor is integrated with an Otto cycle Internal Combustion Engine (ICE). Modelling was carried out using the Aspen Plus™ software to predict the ideal operational conditions for maximum efficiency. Thermodynamics package used in the simulation comprised the Non-Random Two-Liquid (NRTL) model and the Hayden-O'Connell (HOC) equation of state. As expected, the results indicated that the Equivalence Ratio (ER) has a direct influence over the gasification temperature and the composition of the Raw Produced Gas (RPG), and effects of ER over the Lower Heating Value (LHV) and Cold Gasification Efficiency (CGE) of the RPG are also discussed. A maximum CGE efficiency of 57-60% was reached for ER values between 0.25 and 0.3, also an average reactor temperature values in the range of 680-700°C, with a peak LHV of 5.8MJ/Nm 3 . RPG was burned in an ICE, reaching an electrical power of 50kW el . The economic assessment of the pilot plant implementation was also performed, showing the project is feasible, with power above 120kW el with an initial investment of approximately US$ 300,000. Copyright © 2017 Elsevier Ltd. All rights reserved.
Pavlović, Pavle; Mitrović, Miroslava; Djurdjević, Lola
2004-05-01
This ecophysiological research on the ash deposits from the "Nikola Tesla-A" thermal power station in Serbia covered 10 plant species (Tamarix gallica, Populus alba, Spiraea van-hauttei, Ambrosia artemisifolia, Amorpha fruticosa, Eupatorium cannabinum, Crepis setosa, Epilobium collinum, Verbascum phlomoides, and Cirsium arvense). This paper presents the results of a water regime analysis, photosynthetic efficiency and trace elements (B, Cu, Mn, Zn, Pb, and Cd) content in vegetative plant parts. Water regime parameters indicate an overall stability in plant-water relations. During the period of summer drought, photosynthetic efficiency (Fv/Fm) was low, ranging from 0.429 to 0.620 for all the species that were analyzed. An analysis of the tissue trace elements content showed a lower trace metal concentration in the plants than in the ash, indicating that heavy metals undergo major concentration during the combustion process and some are not readily taken up by plants. The Zn and Pb concentrations in all of the examined species were normal whereas Cu and Mn concentrations were in the deficiency range. Boron concentrations in plant tissues were high, with some species even showing levels of more than 100 microg/g (Populus sp., Ambrosia sp., Amorpha sp., and Cirsium sp.). The presence of Cd was not detected. In general, it can be concluded from the results of this research that biological recultivation should take into account the existing ecological, vegetation, and floristic potential of an immediate environment that is abundant in life forms and ecological types of plant species that can overgrow the ash deposit relatively quickly. Selected species should be adapted to toxic B concentrations with moderate demands in terms of mineral elements (Cu and Mn).
NASA Astrophysics Data System (ADS)
Summers, Kodi
The increasing global demand for electricity is straining current resources of fossil fuels and placing increased pressure on the environment. The implementation of alternative sources of energy is paramount to satisfying global electricity demand while reducing reliance on fossil fuels and lessen the impact on the environment. Concentrated solar power (CSP) plants have the ability to harness solar energy at an efficiency not yet achieved by other technologies designed to convert solar energy to electricity. The problem of intermittency in power production seen with other renewable technologies can be virtually eliminated with the use of molten salt as a heat transfer fluid in CSP plants. Commercial and economic success of CSP plants requires operating at maximum efficiency and capacity which requires high temperature and material reliability. This study investigates the corrosion behavior of structural alloys and electrochemical testing in molten nitrate salts at three temperatures common to CSP plants. Corrosion behavior was evaluated using gravimetric and inductively-coupled plasma optical emission spectroscopy (ICP-OES) analysis. Surface morphology was studied using scanning electron microscopy. Surface oxide structure and chemistry was characterized using X-ray diffraction, Raman spectroscopy, energy dispersive spectroscopy, and X-ray photoelectron spectroscopy. Electrochemical behavior of candidate structural alloys Alloy 4130, austenitic stainless steel 316, and super-austenitic Incoloy 800H was evaluated using potentiodynamic polarization characteristics. It was observed that electrochemical evaluation of these candidate materials correlates well with the corrosion behavior observed from gravimetric and ICP-OES analysis. This study identifies that all three alloys exhibited acceptable corrosion in 300°C molten salt while elevated salt temperatures require the more corrosion resistant alloys, stainless steel 316 and 800H. Characterization of the sample surfaces revealed the presence of spinels at lower temperatures, while Fe2O3 was the dominant iron oxide at higher temperatures for each alloy. It is recommended that accelerated corrosion testing be investigated further to evaluate alloys in other molten salt systems considered for utilization in concentrated solar power plants.
Increasing nuclear power at liberalised energy markets- case Finland
NASA Astrophysics Data System (ADS)
Syri, S.; Kurki-Suonio, T.; Satka, V.
2012-10-01
Several Finnish projections for future electricity demand and the need for peak load capacity indicate a demand growth of about 2 GW from the present to the year 2030. The retirement of existing fossil fuel plants and old nuclear power plants will cause increased net import needs during 2020's, even when assuming additional energy efficiency measures and the commissioning of two new nuclear power plants recently approved by the Finnish Parliament. By the year 2030, the need for additional new capacity will be about 6 GW. The increased dependence on import is in contradiction with the official Government targets. This situation is not unique to Finland, but rather is likely to be the case in many other European countries as well. Both the energy company Fortum and energy-intensive industry in Finland see nuclear energy as a viable future generation technology. We describe the « Mankala » concept which is successfully used to build new nuclear capacity at liberalised electricity market in Finland.
Solid oxide fuel cell power plant having a bootstrap start-up system
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lines, Michael T
The bootstrap start-up system (42) achieves an efficient start-up of the power plant (10) that minimizes formation of soot within a reformed hydrogen rich fuel. A burner (48) receives un-reformed fuel directly from the fuel supply (30) and combusts the fuel to heat cathode air which then heats an electrolyte (24) within the fuel cell (12). A dilute hydrogen forming gas (68) cycles through a sealed heat-cycling loop (66) to transfer heat and generated steam from an anode side (32) of the electrolyte (24) through fuel processing system (36) components (38, 40) and back to an anode flow field (26)more » until fuel processing system components (38, 40) achieve predetermined optimal temperatures and steam content. Then, the heat-cycling loop (66) is unsealed and the un-reformed fuel is admitted into the fuel processing system (36) and anode flow (26) field to commence ordinary operation of the power plant (10).« less
KERENA safety concept in the context of the Fukushima accident
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zacharias, T.; Novotny, C.; Bielor, E.
Within the last three years AREVA NP and E.On KK finalized the basic design of KERENA which is a medium sized innovative boiling water reactor, based on the operational experience of German BWR nuclear power plants (NPPs). It is a generation III reactor design with a net electrical output of about 1250 MW. It combines active safety equipment of service-proven designs with new passive safety components, both safety classified. The passive systems utilize basic laws of physics, such as gravity and natural convection, enabling them to function without electric power. Even actuation of these systems is performed thanks to basicmore » physic laws. The degree of diversity in component and system design, achieved by combining active and passive equipment, results in a very low core damage frequency. The Fukushima accident enhanced the world wide discussion about the safety of operating nuclear power plants. World wide stress tests for operating nuclear power plants are being performed embracing both natural and man made hazards. Beside the assessment of existing power plants, also new designs are analyzed regarding the system response to beyond design base accidents. KERENA's optimal combination of diversified cooling systems (active and passive) allows passing efficiently such tests, with a high level of confidence. This paper describes the passive safety components and the KERENA reactor behavior after a Fukushima like accident. (authors)« less
Sakadjian, B.; Hu, S.; Maryamchik, M.; ...
2015-06-05
Solar Particle Receivers (SPR) are under development to drive concentrating solar plants (CSP) towards higher operating temperatures to support higher efficiency power conversion cycles. The novel high temperature SPR-based CSP system uses solid particles as the heat transfer medium (HTM) in place of the more conventional fluids such as molten salt or steam used in current state-of-the-art CSP plants. The solar particle receiver (SPR) is designed to heat the HTM to temperatures of 800 °C or higher which is well above the operating temperatures of nitrate-based molten salt thermal energy storage (TES) systems. The solid particles also help overcome somemore » of the other challenges associated with molten salt-based systems such as freezing, instability and degradation. The higher operating temperatures and use of low cost HTM and higher efficiency power cycles are geared towards reducing costs associated with CSP systems. This paper describes the SPR-based CSP system with a focus on the fluidized-bed (FB) heat exchanger and its integration with various power cycles. Furthermore, the SPR technology provides a potential pathway to achieving the levelized cost of electricity (LCOE) target of $0.06/kWh that has been set by the U.S. Department of Energy's SunShot initiative.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sakadjian, B.; Hu, S.; Maryamchik, M.
Solar Particle Receivers (SPR) are under development to drive concentrating solar plants (CSP) towards higher operating temperatures to support higher efficiency power conversion cycles. The novel high temperature SPR-based CSP system uses solid particles as the heat transfer medium (HTM) in place of the more conventional fluids such as molten salt or steam used in current state-of-the-art CSP plants. The solar particle receiver (SPR) is designed to heat the HTM to temperatures of 800 °C or higher which is well above the operating temperatures of nitrate-based molten salt thermal energy storage (TES) systems. The solid particles also help overcome somemore » of the other challenges associated with molten salt-based systems such as freezing, instability and degradation. The higher operating temperatures and use of low cost HTM and higher efficiency power cycles are geared towards reducing costs associated with CSP systems. This paper describes the SPR-based CSP system with a focus on the fluidized-bed (FB) heat exchanger and its integration with various power cycles. Furthermore, the SPR technology provides a potential pathway to achieving the levelized cost of electricity (LCOE) target of $0.06/kWh that has been set by the U.S. Department of Energy's SunShot initiative.« less
Increasing efficiency of TPP fuel suply system due to LNG usage as a reserve fuel
NASA Astrophysics Data System (ADS)
Zhigulina, E. V.; Khromchenkov, V. G.; Mischner, J.; Yavorovsky, Y. V.
2017-11-01
The paper is devoted to the analysis of fuel economy efficiency increase possibility at thermal power plants (TPP) due to the transition from the use of black oil as a reserve fuel to liquefied natural gas (LNG) produced at the very station. The work represents the technical solution that allows to generate, to store and to use LNG as the reserve fuel TPP. The annual amounts of black oil and natural gas that are needed to ensure the reliable operation of several power plants in Russia were assessed. Some original schemes of the liquefied natural gas production and storing as alternative reserve fuel generated by means of application of expansion turbines are proposed. The simulation results of the expansion process for two compositions of natural gas with different contents of high-boiling fractions are presented. The dependences of the condensation outlet and power generation from the flow initial parameters and from the natural gas composition are obtained and analysed. It was shown that the choice of a particular circuit design depends primarily on the specific natural gas composition. The calculations have proved the effectiveness and the technical ability to use liquefied natural gas as a backup fuel at reconstructed and newly designed gas power station.
About opportunities of the sharing of city infrastructure centralized warmly - and water supply
NASA Astrophysics Data System (ADS)
Zamaleev, M. M.; Gubin, I. V.; Sharapov, V. I.
2017-11-01
It is shown that joint use of engineering infrastructure of centralized heat and water supply of consumers will be the cost-efficient decision for municipal services of the city. The new technology for regulated heating of drinking water in the condenser of steam turbines of combined heat and power plant is offered. Calculation of energy efficiency from application of new technology is executed.
NASA Astrophysics Data System (ADS)
Deetjen, Thomas A.; Reimers, Andrew S.; Webber, Michael E.
2018-02-01
This study estimates changes in grid-wide, energy consumption caused by load shifting via cooling thermal energy storage (CTES) in the building sector. It develops a general equation for relating generator fleet fuel consumption to building cooling demand as a function of ambient temperature, relative humidity, transmission and distribution current, and baseline power plant efficiency. The results present a graphical sensitivity analysis that can be used to estimate how shifting load from cooling demand to cooling storage could affect overall, grid-wide, energy consumption. In particular, because power plants, air conditioners and transmission systems all have higher efficiencies at cooler ambient temperatures, it is possible to identify operating conditions such that CTES increases system efficiency rather than decreasing it as is typical for conventional storage approaches. A case study of the Dallas-Fort Worth metro area in Texas, USA shows that using CTES to shift daytime cooling load to nighttime cooling storage can reduce annual, system-wide, primary fuel consumption by 17.6 MWh for each MWh of installed CTES capacity. The study concludes that, under the right circumstances, cooling thermal energy storage can reduce grid-wide energy consumption, challenging the perception of energy storage as a net energy consumer.
NASA Astrophysics Data System (ADS)
Betrie, G.; Yan, E.; Clark, C.
2016-12-01
Thermoelectric power plants use the highest amount of freshwater second to the agriculture sector. However, there is scarcity of information that characterizes the freshwater use of these plants in the United States. This could be attributed to the lack of model and data that are required to conduct analysis and gain insights. The competition for freshwater among sectors will increase in the future as the amount of freshwater gets limited due climate change and population growth. A model that makes use of less data is urgently needed to conduct analysis and identify adaptation strategies. The objectives of this study are to develop a model and simulate the water use of thermoelectric power plants in the United States. The developed model has heat-balance, climate, cooling system, and optimization modules. It computes the amount of heat rejected to the environment, estimates the quantity of heat exchanged through latent and sensible heat to the environment, and computes the amount of water required per unit generation of electricity. To verify the model, we simulated a total of 876 fossil-fired, nuclear and gas-turbine power plants with different cooling systems (CS) using 2010-2014 data obtained from Energy Information Administration. The CS includes once-through with cooling pond, once-through without cooling ponds, recirculating with induced draft and recirculating with induced draft natural draft. The results show that the model reproduced the observed water use per unit generation of electricity for the most of the power plants. It is also noticed that the model slightly overestimates the water use during the summer period when the input water temperatures are higher. We are investigating the possible reasons for the overestimation and address it in the future work. The model could be used individually or coupled to regional models to analyze various adaptation strategies and improve the water use efficiency of thermoelectric power plants.
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
Cost of enlarged operating zone for an existing Francis runner
NASA Astrophysics Data System (ADS)
Monette, Christine; Marmont, Hugues; Chamberland-Lauzon, Joël; Skagerstrand, Anders; Coutu, André; Carlevi, Jens
2016-11-01
Traditionally, hydro power plants have been operated close to best efficiency point, the more stable operating condition for which they have been designed. However, because of changes in the electricity market, many hydro power plants operators wish to operate their machines differently to fulfil those new market needs. New operating conditions can include whole range operation, many start/stops, extensive low load operation, synchronous condenser mode and power/frequency regulation. Many of these new operating conditions may impose more severe fatigue damage than the traditional base load operation close to best efficiency point. Under these conditions, the fatigue life of the runner may be significantly reduced and reparation or replacement cost might occur sooner than expected. In order to design reliable Francis runners for those new challenging operating scenarios, Andritz Hydro has developed various proprietary tools and design rules. These are used within Andritz Hydro to design mechanically robust Francis runners for the operating scenarios fulfilling customer's specifications. To estimate residual life under different operating scenarios of an existing runner designed years ago for best efficiency base load operation, Andritz Hydro's design rules and tools would necessarily lead to conservative results. While the geometry of a new runner can be modified to fulfil all conservative mechanical design rules, the predicted fatigue life of an existing runner under off-design operating conditions may appear rather short because of the conservative safety factor included in the calculations. The most precise and reliable way to calculate residual life of an existing runner under different operating scenarios is to perform a strain gauge measurement campaign on the runner. This paper presents the runner strain gage measurement campaign of a mid-head Francis turbine over all the operating conditions available during the test, the analysis of the measurement signals and the runner residual life assessment under different operating scenarios. With these results, the maintenance cost of the change in operating mode can then be calculated and foreseen by the power plant owner.
Xu, Xiaogang; Wang, Songling; Liu, Jinlian; Liu, Xinyu
2014-01-01
Blower and exhaust fans consume over 30% of electricity in a thermal power plant, and faults of these fans due to rotation stalls are one of the most frequent reasons for power plant outage failures. To accurately predict the occurrence of fan rotation stalls, we propose a support vector regression machine (SVRM) model that predicts the fan internal pressures during operation, leaving ample time for rotation stall detection. We train the SVRM model using experimental data samples, and perform pressure data prediction using the trained SVRM model. To prove the feasibility of using the SVRM model for rotation stall prediction, we further process the predicted pressure data via wavelet-transform-based stall detection. By comparison of the detection results from the predicted and measured pressure data, we demonstrate that the SVRM model can accurately predict the fan pressure and guarantee reliable stall detection with a time advance of up to 0.0625 s. This superior pressure data prediction capability leaves significant time for effective control and prevention of fan rotation stall faults. This model has great potential for use in intelligent fan systems with stall prevention capability, which will ensure safe operation and improve the energy efficiency of power plants. PMID:24854057
Compact Ceramic Microchannel Heat Exchangers
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lewinsohn, Charles
The objective of the proposed work was to demonstrate the feasibility of a step change in power plant efficiency at a commercially viable cost, by obtaining performance data for prototype, compact, ceramic microchannel heat exchangers. By performing the tasks described in the initial proposal, all of the milestones were met. The work performed will advance the technology from Technology Readiness Level 3 (TRL 3) to Technology Readiness Level 4 (TRL 4) and validate the potential of using these heat exchangers for enabling high efficiency solid oxide fuel cell (SOFC) or high-temperature turbine-based power plants. The attached report will describe howmore » this objective was met. In collaboration with The Colorado School of Mines (CSM), specifications were developed for a high temperature heat exchanger for three commercial microturbines. Microturbines were selected because they are a more mature commercial technology than SOFC, they are a low-volume and high-value target for market entry of high-temperature heat exchangers, and they are essentially scaled-down versions of turbines used in utility-scale power plants. Using these specifications, microchannel dimensions were selected to meet the performance requirements. Ceramic plates were fabricated with microchannels of these dimensions. The plates were tested at room temperature and elevated temperature. Plates were joined together to make modular, heat exchanger stacks that were tested at a variety of temperatures and flow rates. Although gas flow rates equivalent to those in microturbines could not be achieved in the laboratory environment, the results showed expected efficiencies, robust operation under significant temperature gradients at high temperature, and the ability to cycle the stacks. Details of the methods and results are presented in this final report.« less
Energy consumption and load profiling at major airports. Final report
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kennedy, J.
1998-12-01
This report describes the results of energy audits at three major US airports. These studies developed load profiles and quantified energy usage at these airports while identifying procedures and electrotechnologies that could reduce their power consumption. The major power consumers at the airports studied included central plants, runway and taxiway lighting, fuel farms, terminals, people mover systems, and hangar facilities. Several major findings emerged during the study. The amount of energy efficient equipment installed at an airport is directly related to the age of the facility. Newer facilities had more energy efficient equipment while older facilities had much of themore » original electric and natural gas equipment still in operation. As redesign, remodeling, and/or replacement projects proceed, responsible design engineers are selecting more energy efficient equipment to replace original devices. The use of computer-controlled energy management systems varies. At airports, the primary purpose of these systems is to monitor and control the lighting and environmental air conditioning and heating of the facility. Of the facilities studied, one used computer management extensively, one used it only marginally, and one had no computer controlled management devices. At all of the facilities studied, natural gas is used to provide heat and hot water. Natural gas consumption is at its highest in the months of November, December, January, and February. The Central Plant contains most of the inductive load at an airport and is also a major contributor to power consumption inefficiency. Power factor correction equipment was used at one facility but was not installed at the other two facilities due to high power factor and/or lack of need.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
William W. Glauz
The Los Angeles Department of Water and Power (LADWP) has developed one of the most recognized fuel cell demonstration programs in the United States. In addition to their high efficiencies and superior environmental performance, fuel cells and other generating technologies that can be located at or near the load, offers several electric utility benefits. Fuel cells can help further reduce costs by reducing peak electricity demand, thereby deferring or avoiding expenses for additional electric utility infrastructure. By locating generators near the load, higher reliability of service is possible and the losses that occur during delivery of electricity from remote generatorsmore » are avoided. The potential to use renewable and locally available fuels, such as landfill or sewage treatment waste gases, provides another attractive outlook. In Los Angeles, there are also many oil producing areas where the gas by-product can be utilized. In June 2000, the LADWP contracted with FCE to install and commission the precommercial 250kW MCFC power plant. The plant was delivered, installed, and began power production at the JFB in August 2001. The plant underwent manufacturer's field trials up for 18 months and was replace with a commercial plant in January 2003. In January 2001, the LADWP contracted with FCE to provide two additional 250kW MCFC power plants. These commercial plants began operations during mid-2003. The locations of these plants are at the Terminal Island Sewage Treatment Plant at the Los Angeles Harbor (for eventual operation on digester gas) and at the LADWP Main Street Service Center east of downtown Los Angeles. All three carbonate fuel cell plants received partial funding through the Department of Defense's Climate Change Fuel Cell Buydown Program. This report covers the technical evaluation and benefit-cost evaluation of the Main Street 250kW MCFC power plant during its first year of operation from September 2003 to August 2004. The data for the month of September 2004 was not available at the time this report was prepared. An addendum to this report will be prepared and transmitted to the Department of Energy once this data becomes available. This fuel cell power plant was originally intended to be installed at an American Airlines facility located at Los Angeles International Airport, however, due to difficulties in obtaining a site, the plant was ultimately installed at the LADWP's Distributed Generation Test Facility at it's Main Street Service Center.« less