Science.gov

Sample records for overnight electricity generation

  1. Hybrid optimal online-overnight charging coordination of plug-in electric vehicles in smart grid

    NASA Astrophysics Data System (ADS)

    Masoum, Mohammad A. S.; Nabavi, Seyed M. H.

    2016-10-01

    Optimal coordinated charging of plugged-in electric vehicles (PEVs) in smart grid (SG) can be beneficial for both consumers and utilities. This paper proposes a hybrid optimal online followed by overnight charging coordination of high and low priority PEVs using discrete particle swarm optimization (DPSO) that considers the benefits of both consumers and electric utilities. Objective functions are online minimization of total cost (associated with grid losses and energy generation) and overnight valley filling through minimization of the total load levels. The constraints include substation transformer loading, node voltage regulations and the requested final battery state of charge levels (SOCreq). The main challenge is optimal selection of the overnight starting time (toptimal-overnight,start) to guarantee charging of all vehicle batteries to the SOCreq levels before the requested plug-out times (treq) which is done by simultaneously solving the online and overnight objective functions. The online-overnight PEV coordination approach is implemented on a 449-node SG; results are compared for uncoordinated and coordinated battery charging as well as a modified strategy using cost minimizations for both online and overnight coordination. The impact of toptimal-overnight,start on performance of the proposed PEV coordination is investigated.

  2. Electric generator

    DOEpatents

    Foster, Jr., John S.; Wilson, James R.; McDonald, Jr., Charles A.

    1983-01-01

    1. In an electrical energy generator, the combination comprising a first elongated annular electrical current conductor having at least one bare surface extending longitudinally and facing radially inwards therein, a second elongated annular electrical current conductor disposed coaxially within said first conductor and having an outer bare surface area extending longitudinally and facing said bare surface of said first conductor, the contiguous coaxial areas of said first and second conductors defining an inductive element, means for applying an electrical current to at least one of said conductors for generating a magnetic field encompassing said inductive element, and explosive charge means disposed concentrically with respect to said conductors including at least the area of said inductive element, said explosive charge means including means disposed to initiate an explosive wave front in said explosive advancing longitudinally along said inductive element, said wave front being effective to progressively deform at least one of said conductors to bring said bare surfaces thereof into electrically conductive contact to progressively reduce the inductance of the inductive element defined by said conductors and transferring explosive energy to said magnetic field effective to generate an electrical potential between undeformed portions of said conductors ahead of said explosive wave front.

  3. Electrical Generation.

    ERIC Educational Resources Information Center

    Science and Children, 1990

    1990-01-01

    Described are two activities designed to help children investigate electrical charges, electric meters, and electromagnets. Included are background information, a list of materials, procedures, and follow-up questions. Sources of additional information are cited. (CW)

  4. Thermoacoustic magnetohydrodynamic electrical generator

    DOEpatents

    Wheatley, J.C.; Swift, G.W.; Migliori, A.

    1984-11-16

    A thermoacoustic magnetohydrodynamic electrical generator includes an intrinsically irreversible thermoacoustic heat engine coupled to a magnetohydrodynamic electrical generator. The heat engine includes an electrically conductive liquid metal as the working fluid and includes two heat exchange and thermoacoustic structure assemblies which drive the liquid in a push-pull arrangement to cause the liquid metal to oscillate at a resonant acoustic frequency on the order of 1000 Hz. The engine is positioned in the field of a magnet and is oriented such that the liquid metal oscillates in a direction orthogonal to the field of the magnet, whereby an alternating electrical potential is generated in the liquid metal. Low-loss, low-inductance electrical conductors electrically connected to opposite sides of the liquid metal conduct an output signal to a transformer adapted to convert the low-voltage, high-current output signal to a more usable higher voltage, lower current signal.

  5. Thermoacoustic magnetohydrodynamic electrical generator

    DOEpatents

    Wheatley, John C.; Swift, Gregory W.; Migliori, Albert

    1986-01-01

    A thermoacoustic magnetohydrodynamic electrical generator includes an intrinsically irreversible thermoacoustic heat engine coupled to a magnetohydrodynamic electrical generator. The heat engine includes an electrically conductive liquid metal as the working fluid and includes two heat exchange and thermoacoustic structure assemblies which drive the liquid in a push-pull arrangement to cause the liquid metal to oscillate at a resonant acoustic frequency on the order of 1,000 Hz. The engine is positioned in the field of a magnet and is oriented such that the liquid metal oscillates in a direction orthogonal to the field of the magnet, whereby an alternating electrical potential is generated in the liquid metal. Low-loss, low-inductance electrical conductors electrically connected to opposite sides of the liquid metal conduct an output signal to a transformer adapted to convert the low-voltage, high-current output signal to a more usable higher voltage, lower current signal.

  6. Biomass for Electricity Generation

    EIA Publications

    2002-01-01

    This paper examines issues affecting the uses of biomass for electricity generation. The methodology used in the National Energy Modeling System to account for various types of biomass is discussed, and the underlying assumptions are explained.

  7. Wave Motion Electric Generator

    SciTech Connect

    Jacobi, E. F.; Winkler, R. J.

    1983-12-27

    Set out herein is an electrical generator conformed for installation in a buoy, the generator comprising an inverted pendulum having two windings formed at the free end thereof and aligned to articulate between two end stops each provided with a magnetic circuit. As the loops thus pass through the magnetic circuit, electrical current is induced which may be rectified through a full way rectifier to charge up a storage battery. The buoy itself may be ballasted to have its fundamental resonance at more than double the wave frequency with the result that during each passing of a wave at least two induction cycles occur.

  8. Wind electric generator project

    NASA Astrophysics Data System (ADS)

    1983-09-01

    A wind generator was installed and connected at Iowa Western Community College. It is heating water through four hot water tanks and proved to be an excellent demonstration project for the community. The college gets frequent inquiries about the windmill and has been very cooperative in informing the public about the success. The windmill generates more electricity than is needed to heat four hot water heaters and future plans are to hook up more. The project requires very little maintenance.

  9. Overnight Scentsation Rose Plant

    NASA Technical Reports Server (NTRS)

    1998-01-01

    International Flavors and Fragrances Inc., Dr. Braja Mookherjee with the Overnight Scentsation rose plant after its flight aboard NASA's shuttle mission STS-95 for experimentation on scent in microgravity.

  10. Thermophotovoltaic Generation of Electricity

    NASA Astrophysics Data System (ADS)

    Gopinath, Ashok; Coutts, Timothy J.; Luther, Joachim

    Thermophotovoltaic (TPV) technology is a promising new means for the direct conversion of thermal to electric energy. Its potential applications range from military power, to space propulsion, to commercial products for market niches in auxiliary power sources, co-generation of electricity and heat, and high temperature waste heat utilization. The papers in this conference volume are divided into broad sections based on topic as follows: (a) systems and modeling on the performance of the latest TPV systems and current modeling efforts (b) emitter and filter technologies on optical cavity spectral control for energy recuperation, (c) photovoltaic device technologies based on antimony and InGaAs based cell designs.

  11. Economic Analysis of the Leveled Cost of Electricity Generation

    SciTech Connect

    Alonso, Gustavo; Ramirez, J. Ramon; Palacios, Javier C.

    2006-07-01

    Nuclear option is currently a cost competitive option due to among other things the high natural gas prices volatility. Currently, the overnight cost for a new nuclear power plant is estimated between 1200 and 1600 USD/kW with an output power between 1100 and 1600 MWe, construction time, from first concrete to commercial operation, is about five years as it has been demonstrated in the last reactors built in Asia (e.g. Japan and China). In this paper a leveled electricity cost analysis is performed to compared different scenarios of electricity generation using combined cycles by using natural gas and nuclear power stations. A nuclear reactor leveled cost analysis for several overnight costs is performed. Also a sensitivity analysis for construction time and capacity factors is offered. The scenarios considered comprise three different discount rates, 5%, 8% and 10%. (authors)

  12. Wind power. [electricity generation

    NASA Technical Reports Server (NTRS)

    Savino, J. M.

    1975-01-01

    A historical background on windmill use, the nature of wind, wind conversion system technology and requirements, the economics of wind power and comparisons with alternative systems, data needs, technology development needs, and an implementation plan for wind energy are presented. Considerable progress took place during the 1950's. Most of the modern windmills feature a wind turbine electricity generator located directly at the top of their rotor towers.

  13. Electrical pulse generator

    DOEpatents

    Norris, Neil J.

    1979-01-01

    A technique for generating high-voltage, wide dynamic range, shaped electrical pulses in the nanosecond range. Two transmission lines are coupled together by resistive elements distributed along the length of the lines. The conductance of each coupling resistive element as a function of its position along the line is selected to produce the desired pulse shape in the output line when an easily produced pulse, such as a step function pulse, is applied to the input line.

  14. Electricity generation and health.

    PubMed

    Markandya, Anil; Wilkinson, Paul

    2007-09-15

    The provision of electricity has been a great benefit to society, particularly in health terms, but it also carries health costs. Comparison of different forms of commercial power generation by use of the fuel cycle methods developed in European studies shows the health burdens to be greatest for power stations that most pollute outdoor air (those based on lignite, coal, and oil). The health burdens are appreciably smaller for generation from natural gas, and lower still for nuclear power. This same ranking also applies in terms of greenhouse-gas emissions and thus, potentially, to long-term health, social, and economic effects arising from climate change. Nuclear power remains controversial, however, because of public concern about storage of nuclear waste, the potential for catastrophic accident or terrorist attack, and the diversion of fissionable material for weapons production. Health risks are smaller for nuclear fusion, but commercial exploitation will not be achieved in time to help the crucial near-term reduction in greenhouse-gas emissions. The negative effects on health of electricity generation from renewable sources have not been assessed as fully as those from conventional sources, but for solar, wind, and wave power, such effects seem to be small; those of biofuels depend on the type of fuel and the mode of combustion. Carbon dioxide (CO2) capture and storage is increasingly being considered for reduction of CO2 emissions from fossil fuel plants, but the health effects associated with this technology are largely unquantified and probably mixed: efficiency losses mean greater consumption of the primary fuel and accompanying increases in some waste products. This paper reviews the state of knowledge regarding the health effects of different methods of generating electricity.

  15. Electricity generation and health.

    PubMed

    Markandya, Anil; Wilkinson, Paul

    2007-09-15

    The provision of electricity has been a great benefit to society, particularly in health terms, but it also carries health costs. Comparison of different forms of commercial power generation by use of the fuel cycle methods developed in European studies shows the health burdens to be greatest for power stations that most pollute outdoor air (those based on lignite, coal, and oil). The health burdens are appreciably smaller for generation from natural gas, and lower still for nuclear power. This same ranking also applies in terms of greenhouse-gas emissions and thus, potentially, to long-term health, social, and economic effects arising from climate change. Nuclear power remains controversial, however, because of public concern about storage of nuclear waste, the potential for catastrophic accident or terrorist attack, and the diversion of fissionable material for weapons production. Health risks are smaller for nuclear fusion, but commercial exploitation will not be achieved in time to help the crucial near-term reduction in greenhouse-gas emissions. The negative effects on health of electricity generation from renewable sources have not been assessed as fully as those from conventional sources, but for solar, wind, and wave power, such effects seem to be small; those of biofuels depend on the type of fuel and the mode of combustion. Carbon dioxide (CO2) capture and storage is increasingly being considered for reduction of CO2 emissions from fossil fuel plants, but the health effects associated with this technology are largely unquantified and probably mixed: efficiency losses mean greater consumption of the primary fuel and accompanying increases in some waste products. This paper reviews the state of knowledge regarding the health effects of different methods of generating electricity. PMID:17876910

  16. Electric energy generator.

    PubMed

    Chen, Chih-Ta; Islam, Rashed Adnan; Priya, Shashank

    2006-03-01

    This study reports an extremely cost-effective mechanism for converting wind energy into electric energy using piezoelectric bimorph actuators at small scale. The total dimensions of the electric energy generator are 5.08 x 11.6 x 7.7 cm3. The rectangular, box-shaped body of the overall structure is made using 3.2-mm thick plastic. Slits are made on two opposite faces of the box so that two columns and six rows of bimorph actuators can be inserted. Each row of bimorph actuators is separated from each other by a gap of 6 mm, and the two columns of bimorphs are separated from each other by a gap of 6.35 mm. In between the two columns, a cylindrical rod is inserted consisting of six rectangular hooks. The hooks are positioned in such a way that each of them just touches the two bimorphs on either side in a particular row. As the wind flows across the generator, it creates a rotary motion on the attached fan that is converted into vertical motion of the cylindrical rod using the cam-shaft mechanism. This vertical motion of the cylindrical rod creates oscillating stress on the bimorphs due to attached hooks. The bimorphs produce output voltage proportional to the applied oscillating stress through piezoelectric effect. The prototype fabricated in this study was found to generate 1.2 mW power at a wind speed of 12 mph across the load of 1.7 komega.

  17. Ocean wave electric generators

    SciTech Connect

    Rosenberg, H.R.

    1986-02-04

    This patent describes an apparatus for generating electricity from ocean waves. It consists of: 1.) a hollow buoyant duck positioned in the path of waves including a core about the center axis of which the duck rotates, a lower chamber portion having liquid therein and an upper chamber portion having air therein. The air is alternately compressed and expanded by the liquid in the chamber during the rotational motion of the duck caused by waves. A turbine mounted in the upper portion of the duck is driven by the compressed and expanded air. A generator is coupled to the turbine and operated to produce electrical energy and an air bulb; 2.) a spine having a transverse axial shaft anchoring the spine to the ocean floor. The upper portion of the spine engages the duck to maintain the duck in position. The spine has a curved configuration to concentrate and direct wave energy. The spine configuration acts as a scoop to increase the height of wave peaks and as a foil to increase the depth of wave troughs.

  18. Generation of electrical power

    DOEpatents

    Hursen, Thomas F.; Kolenik, Steven A.; Purdy, David L.

    1976-01-01

    A heat-to-electricity converter is disclosed which includes a radioactive heat source and a thermoelectric element of relatively short overall length capable of delivering a low voltage of the order of a few tenths of a volt. Such a thermoelectric element operates at a higher efficiency than longer higher-voltage elements; for example, elements producing 6 volts. In the generation of required power, thermoelectric element drives a solid-state converter which is controlled by input current rather than input voltage and operates efficiently for a high signal-plus-noise to signal ratio of current. The solid-state converter has the voltage gain necessary to deliver the required voltage at the low input of the thermoelectric element.

  19. Overnight Changes Recorded by Phoenix Conductivity Probe

    NASA Technical Reports Server (NTRS)

    2008-01-01

    This graph presents simplified data from overnight measurements by the Thermal and Electrical Conductivity Probe on NASA's Phoenix Mars Lander from noon of the mission's 70th Martian day, or sol, to noon the following sol (Aug. 5 to Aug. 6, 2008).

    The graph shows that water disappeared from the atmosphere overnight, at the same time that electrical measurements detected changes consistent with addition of water to the soil.

    Water in soil appears to increase overnight, when water in the atmosphere disappears.

    The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

  20. Method for protecting an electric generator

    DOEpatents

    Kuehnle, Barry W.; Roberts, Jeffrey B.; Folkers, Ralph W.

    2008-11-18

    A method for protecting an electrical generator which includes providing an electrical generator which is normally synchronously operated with an electrical power grid; providing a synchronizing signal from the electrical generator; establishing a reference signal; and electrically isolating the electrical generator from the electrical power grid if the synchronizing signal is not in phase with the reference signal.

  1. THERMO-ELECTRIC GENERATOR

    DOEpatents

    Jordan, K.C.

    1958-07-22

    The conversion of heat energy into electrical energy by a small compact device is descrtbed. Where the heat energy is supplied by a radioactive material and thermopIIes convert the heat to electrical energy. The particular battery construction includes two insulating discs with conductive rods disposed between them to form a circular cage. In the center of the cage is disposed a cup in which the sealed radioactive source is located. Each thermopile is formed by connecting wires from two adjacent rods to a potnt on an annular ring fastened to the outside of the cup, the ring having insulation on its surface to prevent electrica1 contact with the thermopiles. One advantage of this battery construction is that the radioactive source may be inserted after the device is fabricated, reducing the radiation hazard to personnel assembling the battery.

  2. Heat operated cryogenic electrical generator

    NASA Technical Reports Server (NTRS)

    Wang, T. G.; Saffren, M. M.; Elleman, D. D. (Inventor)

    1975-01-01

    An electrical generator useful for providing electrical power in deep space, is disclosed. The electrical generator utilizes the unusual hydrodynamic property exhibited by liquid helium as it is converted to and from a superfluid state to cause opposite directions of rotary motion for a rotor cell thereof. The physical motion of the rotor cell was employed to move a magnetic field provided by a charged superconductive coil mounted on the exterior of the cell. An electrical conductor was placed in surrounding proximity to the cell to interact with the moving magnetic field provided by the superconductive coil and thereby generate electrical energy. A heat control arrangement was provided for the purpose of causing the liquid helium to be partially converted to and from a superfluid state by being cooled and heated, respectively.

  3. Solar Thermal Electricity Generating System

    NASA Astrophysics Data System (ADS)

    Mishra, Sambeet; Tripathy, Pratyasha

    2012-08-01

    A Solar Thermal Electricity generating system also known as Solar Thermal Power plant is an emerging renewable energy technology, where we generate the thermal energy by concentrating and converting the direct solar radiationat medium/high temperature (300∫C ñ 800∫C). The resulting thermal energy is then used in a thermodynamic cycleto produce electricity, by running a heat engine, which turns a generator to make electricity. Solar thermal power is currently paving the way for the most cost-effective solar technology on a large scale and is heading to establish a cleaner, pollution free and secured future. Photovoltaic (PV) and solar thermal technologies are two main ways of generating energy from the sun, which is considered the inexhaustible source of energy. PV converts sunlight directly into electricity whereas in Solar thermal technology, heat from the sun's rays is concentrated to heat a fluid, whose steam powers a generator that produces electricity. It is similar to the way fossil fuel-burning power plants work except that the steam is produced by the collected heat rather than from the combustion of fossil fuels. In order to generate electricity, five major varieties of solar thermal technologies used are:* Parabolic Trough Solar Electric Generating System (SEGS).* Central Receiver Power Plant.* Solar Chimney Power Plant.* Dish Sterling System.* Solar Pond Power Plant.Most parts of India,Asia experiences a clear sunny weather for about 250 to 300 days a year, because of its location in the equatorial sun belt of the earth, receiving fairly large amount of radiation as compared to many parts of the world especially Japan, Europe and the US where development and deployment of solar technologies is maximum.Whether accompanied with this benefit or not, usually we have to concentrate the solar radiation in order to compensate for the attenuation of solar radiation in its way to earthís surface, which results in from 63,2 GW/m2 at the Sun to 1 kW/m2 at

  4. Electromechanically generating electricity with a gapped-graphene electric generator

    NASA Astrophysics Data System (ADS)

    Dressen, Donald; Golovchenko, Jene

    2015-03-01

    We demonstrate the fabrication and operation of a gapped-graphene electric generator (G-GEG) device. The G-GEG generates electricity from the mechanical oscillation of droplets of electrolytes and ionic liquids. The spontaneous adsorption of ionic species on graphene charges opposing electric double-layer capacitors (EDLCs) on each half of the device. Modulating the area of contact between the droplet and graphene leads to adsorption/desorption of ions, effectively charging/discharging each EDLC and generating a current. The flow of current supports a potential difference across the G-GEG due to the device's internal impedance. Both the magnitude and polarity of the induced current and voltage show a strong dependence on the type of ionic species used, suggesting that certain ions interact more strongly with graphene than others. We find that a simple model circuit consisting of an AC current source in series with a resistor and a time-varying capacitor accurately predicts the device's dynamic behavior. Additionally, we discuss the effect of graphene's intrinsic quantum capacitance on the G-GEG's performance and speculate on the utility of the device in the context of energy harvesting.

  5. Electrical power generation systems - Combat aircraft perspective

    NASA Astrophysics Data System (ADS)

    Moeller, R.

    The electrical power generation system requirements of combat aircraft are briefly examined. In particular, attention is given to customer requirements, development of the installed electrical power in aircraft, electrical load analysis for designing the power generation system, and definition of aircraft electrical power supply characteristics and consumer qualities. The discussion also covers reliability requirements for power generation systems, design of a power generation system, control and protection equipment in power generation systems, and helicopter electrical power systems.

  6. Apparatuses and methods for generating electric fields

    DOEpatents

    Scott, Jill R; McJunkin, Timothy R; Tremblay, Paul L

    2013-08-06

    Apparatuses and methods relating to generating an electric field are disclosed. An electric field generator may include a semiconductive material configured in a physical shape substantially different from a shape of an electric field to be generated thereby. The electric field is generated when a voltage drop exists across the semiconductive material. A method for generating an electric field may include applying a voltage to a shaped semiconductive material to generate a complex, substantially nonlinear electric field. The shape of the complex, substantially nonlinear electric field may be configured for directing charged particles to a desired location. Other apparatuses and methods are disclosed.

  7. Electricity Generation Cost Simulation Model

    2003-04-25

    The Electricity Generation Cost Simulation Model (GENSIM) is a user-friendly, high-level dynamic simulation model that calculates electricity production costs for variety of electricity generation technologies, including: pulverized coal, gas combustion turbine, gas combined cycle, nuclear, solar (PV and thermal), and wind. The model allows the user to quickly conduct sensitivity analysis on key variables, including: capital, O&M, and fuel costs; interest rates; construction time; heat rates; and capacity factors. The model also includes consideration ofmore » a wide range of externality costs and pollution control options for carbon dioxide, nitrogen oxides, sulfur dioxide, and mercury. Two different data sets are included in the model; one from the U.S. Department of Energy (DOE) and the other from Platt's Research Group. Likely users of this model include executives and staff in the Congress, the Administration and private industry (power plant builders, industrial electricity users and electric utilities). The model seeks to improve understanding of the economic viability of various generating technologies and their emission trade-offs. The base case results using the DOE data, indicate that in the absence of externality costs, or renewable tax credits, pulverized coal and gas combined cycle plants are the least cost alternatives at 3.7 and 3.5 cents/kwhr, respectively. A complete sensitivity analysis on fuel, capital, and construction time shows that these results coal and gas are much more sensitive to assumption about fuel prices than they are to capital costs or construction times. The results also show that making nuclear competitive with coal or gas requires significant reductions in capital costs, to the $1000/kW level, if no other changes are made. For renewables, the results indicate that wind is now competitive with the nuclear option and is only competitive with coal and gas for grid connected applications if one includes the federal production tax

  8. Mini-biomass electric generation

    SciTech Connect

    Elliot, G.

    1997-12-01

    Awareness of the living standards achieved by others has resulted in a Russian population which is yearning for a higher standard of living. Such a situation demands access to affordable electricity in remote areas. Remote energy requirements creates the need to transport power or fossil fuels over long distances. Application of local renewable energy resources could eliminate the need for and costs of long distance power supply. Vast forest resources spread over most of Russia make biomass an ideal renewable energy candidate for many off-grid villages. The primary objective for this preliminary evaluation is to examine the economic feasibility of replacing distillate and gasoline fuels with local waste biomass as the primary fuel for village energy in outlying regions of Russia. Approximately 20 million people live in regions where Russia`s Unified Electric System grid does not penetrate. Most of these people are connected to smaller independent power grids, but approximately 8 million Russians live in off-grid villages and small towns served by stand-alone generation systems using either diesel fuel or gasoline. The off-grid villages depend on expensive distillate fuels and gasoline for combustion in small boilers and engines. These fuels are used for both electricity generation and district heating. Typically, diesel generator systems with a capacity of up to 1 MW serve a collective farm, settlement and their rural enterprises (there are an estimated 10,000 such systems in Russia). Smaller gasoline-fueled generator systems with capacities in the range of 0.5 - 5 kW serve smaller farms or rural enterprises (there are about 60,000 such systems in Russia).

  9. Electricity generation from defective tomatoes.

    PubMed

    Shrestha, Namita; Fogg, Alex; Wilder, Joseph; Franco, Daniel; Komisar, Simeon; Gadhamshetty, Venkataramana

    2016-12-01

    The United States faces a significant burden in treating 0.61billionkg of defective tomatoes (culls) every year. We present a proof-of-concept for generating electricity from culled tomatoes in microbial-electrochemical systems (MESs). This study delineates impedance behavior of the culled tomatoes in MESs and compares its impedance spectra with that of soluble substrates (dextrose, acetate, and wastewater). A series of AC and DC diagnostic tests have revealed the superior performance of the culled tomatoes compared to the pure substrates. Cyclic voltammetry results have indicated the active role of indigenous, diffusible redox-active pigments in the culled tomatoes on overall electricity production. Electrochemical impedance spectroscopy results have elucidated the role of peel and seed on the oxidation behavior of the culled tomatoes. PMID:27474917

  10. The Overnight Scentsation Rose Plant

    NASA Technical Reports Server (NTRS)

    1998-01-01

    International Flavors and Fragrances Inc., is a company that creates and manufactures flavors, fragrances and aroma chemicals. The Overnight Scentsation rose plant will be housed aboard NASA's shuttle flight STS-95 in a specially-designed structure under ultraviolet lights. The flowering plant was brought to Cape Canaveral from its home at IFF's greenhouse in Union Beach, New Jersey.

  11. Wind wheel electric power generator

    SciTech Connect

    Kaufman, J.W.

    1980-03-04

    Wind wheel electric power generator apparatus is disclosed as including a housing rotatably mounted upon a vertically disposed support column. Primary and auxiliary funnel-type, venturi ducts are fixedly mounted upon the housing for capturing wind currents and for conducting the same to a bladed wheel adapted to be operatively connected with generator apparatus. Additional air flows are also conducted onto the bladed wheel, all of the air flows positively effecting rotation of the wheel in a cumulative manner. The auxiliary ducts are disposed at an acute angle with respect to the longitudinal axis of the housing, and this feature , together with the rotatability of the housing and the ducts, permits capture of wind currents within a variable directional range.

  12. Wind wheel electric power generator

    NASA Technical Reports Server (NTRS)

    Kaufman, J. W. (Inventor)

    1980-01-01

    Wind wheel electric power generator apparatus includes a housing rotatably mounted upon a vertical support column. Primary and auxiliary funnel-type, venturi ducts are fixed onto the housing for capturing wind currents and conducting to a bladed wheel adapted to be operatively connected with the generator apparatus. Additional air flows are also conducted onto the bladed wheel; all of the air flows positively effecting rotation of the wheel in a cumulative manner. The auxiliary ducts are disposed at an acute angle with respect to the longitudinal axis of the housing, and this feature, together with the rotatability of the housing and the ducts, permits capture of wind currents within a variable directional range.

  13. Solar energy thermally powered electrical generating system

    NASA Technical Reports Server (NTRS)

    Owens, William R. (Inventor)

    1989-01-01

    A thermally powered electrical generating system for use in a space vehicle is disclosed. The rate of storage in a thermal energy storage medium is controlled by varying the rate of generation and dissipation of electrical energy in a thermally powered electrical generating system which is powered from heat stored in the thermal energy storage medium without exceeding a maximum quantity of heat. A control system (10) varies the rate at which electrical energy is generated by the electrical generating system and the rate at which electrical energy is consumed by a variable parasitic electrical load to cause storage of an amount of thermal energy in the thermal energy storage system at the end of a period of insolation which is sufficient to satisfy the scheduled demand for electrical power to be generated during the next period of eclipse. The control system is based upon Kalman filter theory.

  14. Electrical power generating system. [for windpowered generation

    NASA Technical Reports Server (NTRS)

    Nola, F. J. (Inventor)

    1981-01-01

    An alternating current power generation system adopted to inject power in an already powered power line is discussed. The power generating system solves to adjustably coup an induction motor, as a generator, to an ac power line wherein the motor and power line are connected through a triac. The triac is regulated to normally turn on at a relatively late point in each half cycle of its operation, whereby at less than operating speed, and thus when the induction motor functions as a motor rather than as a generator, power consumption from the line is substantially reduced. The principal application will be for windmill powered generation.

  15. LIFE CYCLE ASSESSMENT OF ELECTRICITY GENERATION ALTERNATIVES

    EPA Science Inventory

    This presentation summarizes various electricity and electricity/steam cogeneration alternatives. Among these alternatives, are fossil fuel and biomass power generation plants. These plants have different designs due to the need in fossil fuel (coal) plants to include process u...

  16. Wind turbine generator for electrical powered vehicles

    SciTech Connect

    Boodman, L.; Malone, J.P.

    1982-02-02

    Means to provide additional electrical power in an electrically powered vehicle are disclosed. An air scoop is mounted on the vehicle. The air scoop opens in a generally forward direction. A turbine wheel is mounted in the rear of the air scoop. An electric generator is connected to the turbine wheel, whereby air passing through the air scoop will generate additional electricity for the vehicle batteries. The air scoop is rotatable and means are provided to lock it in position.

  17. Electrical power generation by mechanically modulating electrical double layers.

    PubMed

    Moon, Jong Kyun; Jeong, Jaeki; Lee, Dongyun; Pak, Hyuk Kyu

    2013-01-01

    Since Michael Faraday and Joseph Henry made their great discovery of electromagnetic induction, there have been continuous developments in electrical power generation. Most people today get electricity from thermal, hydroelectric, or nuclear power generation systems, which use this electromagnetic induction phenomenon. Here we propose a new method for electrical power generation, without using electromagnetic induction, by mechanically modulating the electrical double layers at the interfacial areas of a water bridge between two conducting plates. We find that when the height of the water bridge is mechanically modulated, the electrical double layer capacitors formed on the two interfacial areas are continuously charged and discharged at different phases from each other, thus generating an AC electric current across the plates. We use a resistor-capacitor circuit model to explain the results of this experiment. This observation could be useful for constructing a micro-fluidic power generation system in the near future. PMID:23403587

  18. Electrical power generation by mechanically modulating electrical double layers.

    PubMed

    Moon, Jong Kyun; Jeong, Jaeki; Lee, Dongyun; Pak, Hyuk Kyu

    2013-01-01

    Since Michael Faraday and Joseph Henry made their great discovery of electromagnetic induction, there have been continuous developments in electrical power generation. Most people today get electricity from thermal, hydroelectric, or nuclear power generation systems, which use this electromagnetic induction phenomenon. Here we propose a new method for electrical power generation, without using electromagnetic induction, by mechanically modulating the electrical double layers at the interfacial areas of a water bridge between two conducting plates. We find that when the height of the water bridge is mechanically modulated, the electrical double layer capacitors formed on the two interfacial areas are continuously charged and discharged at different phases from each other, thus generating an AC electric current across the plates. We use a resistor-capacitor circuit model to explain the results of this experiment. This observation could be useful for constructing a micro-fluidic power generation system in the near future.

  19. Entanglement generation by electric field background

    SciTech Connect

    Ebadi, Zahra Mirza, Behrouz

    2014-12-15

    The quantum vacuum is unstable under the influence of an external electric field and decays into pairs of charged particles, a process which is known as the Schwinger pair production. We propose and demonstrate that this electric field can generate entanglement. Using the Schwinger pair production for constant and pulsed electric fields, we study entanglement for scalar particles with zero spins and Dirac fermions. One can observe the variation of the entanglement produced for bosonic and fermionic modes with respect to different parameters.

  20. Electrical Power Generation by Mechanically Modulating Electrical Double Layers

    NASA Astrophysics Data System (ADS)

    Pak, Hyuk Kyu; Moon, Jong Kyun

    2014-11-01

    Since Michael Faraday and Joseph Henry made their great discovery of electromagnetic induction, there have been continuous developments in electrical power generation. Most people today get electricity from thermal, hydroelectric, or nuclear power generation systems, which use this electromagnetic induction phenomenon. Here we propose a new method for electrical power generation, without using electromagnetic induction, by mechanically modulating the electrical double layers at the interfacial areas of a water bridge between two conducting plates. We find that when the height of the water bridge is mechanically modulated, the electrical double layer capacitors formed on the two interfacial areas are continuously charged and discharged at different phases from each other, thus generating an AC electric current across the plates. We use a resistor-capacitor circuit model to explain the results of this experiment. This observation could be useful for constructing a micro-fluidic power generation system and for understanding the interfacial charge distribution in solid-liquid interfaces in the near future. This work was supported by Center for Soft and Living Matter through IBS prgram in Korea.

  1. Evaluation of biomass systems for electricity generation

    NASA Astrophysics Data System (ADS)

    Lipinsky, E. S.; Ball, D. A.; Anson, D.

    1982-02-01

    State-of-the-art information and evaluation of alternative biomass systems for generation of electricity are provided. The biomass systems consist of silvicultural or agricultural resources, processing and conversion technology to make biomass-derived fuels, and electricity-generating technology. The systems are delineated in energy network charts and are evaluated in matrices that display biomass-system alternatives and multiple technical, economic, and environmental-impact criteria.

  2. Electricity generation by intermittent sources

    NASA Astrophysics Data System (ADS)

    Wagner, F.

    2015-08-01

    This paper deals with the production of electricity by wind and photovoltaic (PV) power mostly in Germany. The German data of 2012 are scaled to a 100% supply of the electricity consumption by renewable sources. Wind and PV power are mixed in a ratio which minimises back-up energy. The 100%, optimal mix data are used to identify the powers to be installed, the accumulating backup and surplus energies, the size of storage to replace thermal back-up power, the possibilities of demand-side-management, and the specific CO2 production. The benefits of using an EU-wide field of renewable energies (RES) instead of the national one are quantified and the interconnection capacities specified. Finally, the costs of installing RES are discussed. The conclusion is that a 100% supply by RES may not be meaningful. Large-scale supply by RES alone has deficiencies and it will remain a major task for science and technology to either improve such a system or find a suitable replacement.

  3. Traveling-wave thermoacoustic electric generator

    NASA Astrophysics Data System (ADS)

    Backhaus, S.; Tward, E.; Petach, M.

    2004-08-01

    Traveling-wave thermoacoustic heat engines have been demonstrated to convert high-temperature heat to acoustic power with high efficiency without using moving parts. Electrodynamic linear alternators and compressors have demonstrated high acoustic-to-electric transduction efficiency as well as long maintenance-free lifetimes. By optimizing a small-scale traveling-wave thermoacoustic engine for use with an electrodynamic linear alternator, we have created a traveling-wave thermoacoustic electric generator; a power conversion system suitable for demanding applications such as electricity generation aboard spacecraft.

  4. Fluidic Active Transducer for Electricity Generation.

    PubMed

    Yang, YoungJun; Park, Junwoo; Kwon, Soon-Hyung; Kim, Youn Sang

    2015-01-01

    Flows in small size channels have been studied for a long time over multidisciplinary field such as chemistry, biology and medical through the various topics. Recently, the attempts of electricity generation from the small flows as a new area for energy harvesting in microfluidics have been reported. Here, we propose for the first time a new fluidic electricity generator (FEG) by modulating the electric double layer (EDL) with two phase flows of water and air without external power sources. We find that an electric current flowed by the forming/deforming of the EDL with a simple separated phase flow of water and air at the surface of the FEG. Electric signals between two electrodes of the FEG are checked from various water/air passing conditions. Moreover, we verify the possibility of a self-powered air slug sensor by applying the FEG in the detection of an air slug.

  5. Fluidic Active Transducer for Electricity Generation

    PubMed Central

    Yang, YoungJun; Park, Junwoo; Kwon, Soon-Hyung; Kim, Youn Sang

    2015-01-01

    Flows in small size channels have been studied for a long time over multidisciplinary field such as chemistry, biology and medical through the various topics. Recently, the attempts of electricity generation from the small flows as a new area for energy harvesting in microfluidics have been reported. Here, we propose for the first time a new fluidic electricity generator (FEG) by modulating the electric double layer (EDL) with two phase flows of water and air without external power sources. We find that an electric current flowed by the forming/deforming of the EDL with a simple separated phase flow of water and air at the surface of the FEG. Electric signals between two electrodes of the FEG are checked from various water/air passing conditions. Moreover, we verify the possibility of a self-powered air slug sensor by applying the FEG in the detection of an air slug. PMID:26511626

  6. Electricity generation choices for the near term

    NASA Astrophysics Data System (ADS)

    Bodansky, D.

    1980-02-01

    The alternatives available for the generation of electricity in the United States in the next few decades are evaluated. The present sources of electricity and recent trends in the amount of electricity generated by the various sources are reviewed, and widely varying projections of future energy demand are discussed, noting that electricity demand is expected to increase considerably if a significant reduction in oil consumption is achieved. The renewable energy resources hydroelectric power, biomass energy, geothermal power, direct solar power and wind energy are found to be incapable of making a major contribution to electricity expansion by the year 2000. Coal and nuclear power are then discussed as the most practical alternatives, and the advantages of nuclear power in the areas of cost and safety, despite the Three Mile Island accident, are pointed out. It is concluded that for the near future, all of the possible options deserve investigation.

  7. Fluidic Active Transducer for Electricity Generation.

    PubMed

    Yang, YoungJun; Park, Junwoo; Kwon, Soon-Hyung; Kim, Youn Sang

    2015-01-01

    Flows in small size channels have been studied for a long time over multidisciplinary field such as chemistry, biology and medical through the various topics. Recently, the attempts of electricity generation from the small flows as a new area for energy harvesting in microfluidics have been reported. Here, we propose for the first time a new fluidic electricity generator (FEG) by modulating the electric double layer (EDL) with two phase flows of water and air without external power sources. We find that an electric current flowed by the forming/deforming of the EDL with a simple separated phase flow of water and air at the surface of the FEG. Electric signals between two electrodes of the FEG are checked from various water/air passing conditions. Moreover, we verify the possibility of a self-powered air slug sensor by applying the FEG in the detection of an air slug. PMID:26511626

  8. Electrical Power Generation by Mechanically Modulating Electrical Double Layers

    NASA Astrophysics Data System (ADS)

    Lee, Dongyun; Moon, Jong Kyun; Jeong, Jaeki; Pak, Hyuk Kyu

    2012-11-01

    Many objects in contact with a liquid acquire some electronic charges on their surfaces. These charges on the surface attract counter ions from the liquid phase. This complex system is called electrical double layer (EDL). Since its geometry and structure is similar to an electric capacitor, it is also called an electrical double layer capacitor (EDLC). In this work we studied two EDLCs formed in a liquid droplet bridge between two parallel solid conducting plates. We found that when the bridge height was mechanically modulated, each EDLC was continuously charged and discharged generating an AC electric current across the plates. The results of this experiment can be useful for constructing a micro-fluidic power generation.

  9. Algae fuel clean electricity generation

    SciTech Connect

    O'Sullivan, D.

    1993-02-08

    The paper describes plans for a 600-kW pilot generating unit, fueled by diesel and Chlorella, a green alga commonly seen growing on the surface of ponds. The plant contains Biocoil units in which Chlorella are grown using the liquid effluents from sewage treatment plants and dissolved carbon dioxide from exhaust gases from the combustion unit. The algae are partially dried and fed into the combustor where diesel fuel is used to maintain ignition. Diesel fuel is also used for start-up and as a backup fuel for seasonal shifts that affect the algae growing conditions. Since the algae use the carbon dioxide emitted during the combustion process, the process will not contribute to global warming.

  10. Dysfunctional overnight memory consolidation in ecstasy users.

    PubMed

    Smithies, Vanessa; Broadbear, Jillian; Verdejo-Garcia, Antonio; Conduit, Russell

    2014-08-01

    Sleep plays an important role in the consolidation and integration of memory in a process called overnight memory consolidation. Previous studies indicate that ecstasy users have marked and persistent neurocognitive and sleep-related impairments. We extend past research by examining overnight memory consolidation among regular ecstasy users (n=12) and drug naïve healthy controls (n=26). Memory recall of word pairs was evaluated before and after a period of sleep, with and without interference prior to testing. In addition, we assessed neurocognitive performances across tasks of learning, memory and executive functioning. Ecstasy users demonstrated impaired overnight memory consolidation, a finding that was more pronounced following associative interference. Additionally, ecstasy users demonstrated impairments on tasks recruiting frontostriatal and hippocampal neural circuitry, in the domains of proactive interference memory, long-term memory, encoding, working memory and complex planning. We suggest that ecstasy-associated dysfunction in fronto-temporal circuitry may underlie overnight consolidation memory impairments in regular ecstasy users.

  11. Subabul: A wood species for electricity generation

    SciTech Connect

    Kumar, M.; Gupta, R.C.

    1996-10-01

    In view of energy and environmental considerations, efforts have been made in this article to suggest the use of biomass as a renewable and nonpolluting source of energy for power generation. This article presents the results of the proximate analyses and energy contents of various components of the Subabul tree and their impact on land requirements to generate necessary biomass for small-scale electricity generation units. The results have shown that for the Subabul-wood-based thermal power plant, approximately 400 ha of land are required to generate 2,000 kWh/d.

  12. Partnership for electrical generation technology education

    SciTech Connect

    Rasmussen, R. S.; Beaty, L.; Holman, R.

    2006-07-01

    This Engineering Technician education effort adapts an existing two-year Instrumentation and Control (I and C) education program into a model that is focused on electrical-generation technologies. It will also locally implement a program developed elsewhere with National Science Foundation funding, aimed at public schools, and adapt it to stimulate pre-college interest in pursuing energy careers in general. (authors)

  13. Implementation of optimum solar electricity generating system

    SciTech Connect

    Singh, Balbir Singh Mahinder Karim, Samsul Ariffin A.; Sivapalan, Subarna; Najib, Nurul Syafiqah Mohd; Menon, Pradeep

    2014-10-24

    Under the 10{sup th} Malaysian Plan, the government is expecting the renewable energy to contribute approximately 5.5% to the total electricity generation by the year 2015, which amounts to 98MW. One of the initiatives to ensure that the target is achievable was to establish the Sustainable Energy Development Authority of Malaysia. SEDA is given the authority to administer and manage the implementation of the feed-in tariff (FiT) mechanism which is mandated under the Renewable Energy Act 2011. The move to establish SEDA is commendable and the FiT seems to be attractive but there is a need to create awareness on the implementation of the solar electricity generating system (SEGS). In Malaysia, harnessing technologies related to solar energy resources have great potential for implementation. However, the main issue that plagues the implementation of SEGS is the intermittent nature of this source of energy. The availability of sunlight is during the day time, and there is a need for electrical energy storage system, so that there is electricity available during the night time as well. The meteorological condition such as clouds, haze and pollution affects the SEGS as well. The PV based SEGS is seems to be promising electricity generating system that can contribute towards achieving the 5.5% target and will be able to minimize the negative effects of utilizing fossil fuels for electricity generation on the environment. Malaysia is committed to Kyoto Protocol, which emphasizes on fighting global warming by achieving stabilization of greenhouse gas concentrations in the atmosphere at a level that would prevent dangerous anthropogenic interference with the climate system. In this paper, the technical aspects of the implementation of optimum SEGS is discussed, especially pertaining to the positioning of the PV panels.

  14. Implementation of optimum solar electricity generating system

    NASA Astrophysics Data System (ADS)

    Singh, Balbir Singh Mahinder; Sivapalan, Subarna; Najib, Nurul Syafiqah Mohd; Menon, Pradeep; Karim, Samsul Ariffin A.

    2014-10-01

    Under the 10th Malaysian Plan, the government is expecting the renewable energy to contribute approximately 5.5% to the total electricity generation by the year 2015, which amounts to 98MW. One of the initiatives to ensure that the target is achievable was to establish the Sustainable Energy Development Authority of Malaysia. SEDA is given the authority to administer and manage the implementation of the feed-in tariff (FiT) mechanism which is mandated under the Renewable Energy Act 2011. The move to establish SEDA is commendable and the FiT seems to be attractive but there is a need to create awareness on the implementation of the solar electricity generating system (SEGS). In Malaysia, harnessing technologies related to solar energy resources have great potential for implementation. However, the main issue that plagues the implementation of SEGS is the intermittent nature of this source of energy. The availability of sunlight is during the day time, and there is a need for electrical energy storage system, so that there is electricity available during the night time as well. The meteorological condition such as clouds, haze and pollution affects the SEGS as well. The PV based SEGS is seems to be promising electricity generating system that can contribute towards achieving the 5.5% target and will be able to minimize the negative effects of utilizing fossil fuels for electricity generation on the environment. Malaysia is committed to Kyoto Protocol, which emphasizes on fighting global warming by achieving stabilization of greenhouse gas concentrations in the atmosphere at a level that would prevent dangerous anthropogenic interference with the climate system. In this paper, the technical aspects of the implementation of optimum SEGS is discussed, especially pertaining to the positioning of the PV panels.

  15. Electric generation of vortices in polariton superfluids

    NASA Astrophysics Data System (ADS)

    Flayac, H.; Pavlovic, G.; Kaliteevski, M. A.; Shelykh, I. A.

    2012-02-01

    We have theoretically demonstrated the on-demand electric generation of vortices in an exciton-polariton superfluid. Electric pulses applied to a horseshoe-shaped metallic mesa, deposited on top of the microcavity, generate a noncylindrically symmetric solitonic wave in the system. Breakdown of its wave front at focal points leads to the formation of vortex-antivortex pairs, which subsequently propagate in the superfluid. The trajectory of these vortex dipoles can be controlled by applying a voltage to additional electrodes. They can be confined within channels formed by metallic stripes and unbound by a wedged mesa giving birth to grey solitons. Finally, single static vortices can be generated using a single metallic plate configuration.

  16. Electric voltage generation by antiferromagnetic dynamics

    NASA Astrophysics Data System (ADS)

    Yamane, Yuta; Ieda, Jun'ichi; Sinova, Jairo

    2016-05-01

    We theoretically demonstrate dc and ac electric voltage generation due to spin motive forces originating from domain wall motion and magnetic resonance, respectively, in two-sublattice antiferromagnets. Our theory accounts for the canting between the sublattice magnetizations, the nonadiabatic electron spin dynamics, and the Rashba spin-orbit coupling, with the intersublattice electron dynamics treated as a perturbation. This work suggests a way to observe and explore the dynamics of antiferromagnetic textures by electrical means, an important aspect in the emerging field of antiferromagnetic spintronics, where both manipulation and detection of antiferromagnets are needed.

  17. Electrical power systems for distributed generation

    SciTech Connect

    Robertson, T.A.; Huval, S.J.

    1996-12-31

    {open_quotes}Distributed Generation{close_quotes} has become the {open_quotes}buzz{close_quotes} word of an electric utility industry facing deregulation. Many industrial facilities utilize equipment in distributed installations to serve the needs of a thermal host through the capture of exhaust energy in a heat recovery steam generator. The electrical power generated is then sold as a {open_quotes}side benefit{close_quotes} to the cost-effective supply of high quality thermal energy. Distributed generation is desirable for many different reasons, each with unique characteristics of the product. Many years of experience in the distributed generation market has helped Stewart & Stevenson to define a range of product features that are crucial to most any application. The following paper will highlight a few of these applications. The paper will also examine the range of products currently available and in development. Finally, we will survey the additional services offered by Stewart & Stevenson to meet the needs of a rapidly changing power generation industry.

  18. A mechanical model of overnight hair curling.

    PubMed

    Xiao, Hang; Chen, Xi

    2015-09-01

    Based on the observation of overnight hair curling procedure, we establish a mechanical model to describe the temporary wave formation of straight hair (initial curvature is zero), which incorporates the contact between hair and hair roller. Systematic studies are carried out to explore the effects of radius ratio between hair and hair roller, hair's average axial strain, creep time, Poisson's ratio and gravity on the curl retention. The variation of curl retention with respect to time obtained from our numerical model is validated by a simple theoretical model and by overnight curling experiments on hair samples. The results of simulation show that overnight hair curling is suitable to create a wavy hairstyle within about 7 hours, while the combined usage with hair fixatives enables a wavy hairstyle with desired curvature that lasts for a day or more.

  19. Motion Generated Static Electricity in Metals

    NASA Astrophysics Data System (ADS)

    Liao Feng, Chung

    2004-03-01

    The charge state of a metallic object, neutral when stationary, is observed to become positive when in motion. This phenomenon was discovered while testing a hypothesis which expects atoms to be more positive when moving faster. The same hypothesis has also led to the discovery of the phenomena of static electric charges being produced by thermal changes during vaporization, condensation and heating of water. The phenomena due to thermal changes were reported at the American Physical Society meetings of MAR02 (W30 4: Electricity of Vaporization and Condensation) and MAR03 (J1 206: Static Electricity from Heating and Cooling). The phenomenon of charges generated by motion can be seen in simple experiments, by the difference in the charge state of a metal rotor between motionless and spinning. The hypothesis and the phenomenon will be discussed. Some of the experiments will be demonstrated.

  20. Why do particle clouds generate electric charges?

    NASA Astrophysics Data System (ADS)

    Pähtz, T.; Herrmann, H. J.; Shinbrot, T.

    2010-05-01

    Grains in desert sandstorms spontaneously generate strong electrical charges; likewise volcanic dust plumes produce spectacular lightning displays. Charged particle clouds also cause devastating explosions in food, drug and coal processing industries. Despite the wide-ranging importance of granular charging in both nature and industry, even the simplest aspects of its causes remain elusive, because it is difficult to understand how inert grains in contact with little more than other inert grains can generate the large charges observed. Here, we present a simple yet predictive explanation for the charging of granular materials in collisional flows. We argue from very basic considerations that charge transfer can be expected in collisions of identical dielectric grains in the presence of an electric field, and we confirm the model's predictions using discrete-element simulations and a tabletop granular experiment.

  1. Negative reinforcement impairs overnight memory consolidation.

    PubMed

    Stamm, Andrew W; Nguyen, Nam D; Seicol, Benjamin J; Fagan, Abigail; Oh, Angela; Drumm, Michael; Lundt, Maureen; Stickgold, Robert; Wamsley, Erin J

    2014-11-01

    Post-learning sleep is beneficial for human memory. However, it may be that not all memories benefit equally from sleep. Here, we manipulated a spatial learning task using monetary reward and performance feedback, asking whether enhancing the salience of the task would augment overnight memory consolidation and alter its incorporation into dreaming. Contrary to our hypothesis, we found that the addition of reward impaired overnight consolidation of spatial memory. Our findings seemingly contradict prior reports that enhancing the reward value of learned information augments sleep-dependent memory processing. Given that the reward followed a negative reinforcement paradigm, consolidation may have been impaired via a stress-related mechanism.

  2. Negative reinforcement impairs overnight memory consolidation.

    PubMed

    Stamm, Andrew W; Nguyen, Nam D; Seicol, Benjamin J; Fagan, Abigail; Oh, Angela; Drumm, Michael; Lundt, Maureen; Stickgold, Robert; Wamsley, Erin J

    2014-11-01

    Post-learning sleep is beneficial for human memory. However, it may be that not all memories benefit equally from sleep. Here, we manipulated a spatial learning task using monetary reward and performance feedback, asking whether enhancing the salience of the task would augment overnight memory consolidation and alter its incorporation into dreaming. Contrary to our hypothesis, we found that the addition of reward impaired overnight consolidation of spatial memory. Our findings seemingly contradict prior reports that enhancing the reward value of learned information augments sleep-dependent memory processing. Given that the reward followed a negative reinforcement paradigm, consolidation may have been impaired via a stress-related mechanism. PMID:25320351

  3. Negative reinforcement impairs overnight memory consolidation

    PubMed Central

    Stamm, Andrew W.; Nguyen, Nam D.; Seicol, Benjamin J.; Fagan, Abigail; Oh, Angela; Drumm, Michael; Lundt, Maureen; Stickgold, Robert

    2014-01-01

    Post-learning sleep is beneficial for human memory. However, it may be that not all memories benefit equally from sleep. Here, we manipulated a spatial learning task using monetary reward and performance feedback, asking whether enhancing the salience of the task would augment overnight memory consolidation and alter its incorporation into dreaming. Contrary to our hypothesis, we found that the addition of reward impaired overnight consolidation of spatial memory. Our findings seemingly contradict prior reports that enhancing the reward value of learned information augments sleep-dependent memory processing. Given that the reward followed a negative reinforcement paradigm, consolidation may have been impaired via a stress-related mechanism. PMID:25320351

  4. The Birth of Nuclear-Generated Electricity

    DOE R&D Accomplishments Database

    1999-09-01

    The Experimental Breeder Reactor-I (EBR-I), built in Idaho in 1949, generated the first usable electricity from nuclear power on December 20, 1951. More importantly, the reactor was used to prove that it was possible to create more nuclear fuel in the reactor than it consumed during operation -- fuel breeding. The EBR-I facility is now a National Historic Landmark open to the public.

  5. An overview of thermophotovoltaic generation of electricity

    SciTech Connect

    Coutts, T.J.

    1999-09-09

    This paper provides an overview of the developments in thermophotovoltaic (TPV) generation of electricity that have occurred relatively recently-from about 1994 to October 1998. The components considered are the semiconductor converter; the radiator; and the means of recirculating unusable, long-wavelength photons. A short account of the functions and performance of each of these components is given. Also discussed are operational systems and progress in modeling TPV systems.

  6. Negative Reinforcement Impairs Overnight Memory Consolidation

    ERIC Educational Resources Information Center

    Stamm, Andrew W.; Nguyen, Nam D.; Seicol, Benjamin J.; Fagan, Abigail; Oh, Angela; Drumm, Michael; Lundt, Maureen; Stickgold, Robert; Wamsley, Erin J.

    2014-01-01

    Post-learning sleep is beneficial for human memory. However, it may be that not all memories benefit equally from sleep. Here, we manipulated a spatial learning task using monetary reward and performance feedback, asking whether enhancing the salience of the task would augment overnight memory consolidation and alter its incorporation into…

  7. Microbial electricity generation via microfluidic flow control.

    PubMed

    Li, Zhiqiang; Zhang, Ying; LeDuc, Philip R; Gregory, Kelvin B

    2011-09-01

    Next generation battery technology is rapidly evolving to meet the demand for higher power densities and smaller footprints through novel catalysts and battery architecture. We present a µ-scale, biological fuel cell which utilizes microbial electricity generation enabled by microfluidic flow control to produce power. The new fuel cell, the smallest of its kind, with a total volume of 0.3 µL, produces scalable and controllable electrical energy from organic matter which is sustained through microbial respiration and laminar flow separation of the electrolytes. Electrical currents are dependent on specific biofilm formation on the anode, the concentration of electron donor, and a diffusion-limited flow regime. A maximum current density of 18.40 ± 3.48 mA m(-2) (92 ± 17 A m(-3)) was produced by Geobacter sulfurreducens, and 25.42 mA m(-2) (127 A m(-3)) by Shewanella oneidensis. The µ-scale biological fuel cell introduces the necessary small size and fuel flexibility for applications in vivo and in situ sensors which may be remotely deployed and self-powered. PMID:21495007

  8. Microbial electricity generation via microfluidic flow control.

    PubMed

    Li, Zhiqiang; Zhang, Ying; LeDuc, Philip R; Gregory, Kelvin B

    2011-09-01

    Next generation battery technology is rapidly evolving to meet the demand for higher power densities and smaller footprints through novel catalysts and battery architecture. We present a µ-scale, biological fuel cell which utilizes microbial electricity generation enabled by microfluidic flow control to produce power. The new fuel cell, the smallest of its kind, with a total volume of 0.3 µL, produces scalable and controllable electrical energy from organic matter which is sustained through microbial respiration and laminar flow separation of the electrolytes. Electrical currents are dependent on specific biofilm formation on the anode, the concentration of electron donor, and a diffusion-limited flow regime. A maximum current density of 18.40 ± 3.48 mA m(-2) (92 ± 17 A m(-3)) was produced by Geobacter sulfurreducens, and 25.42 mA m(-2) (127 A m(-3)) by Shewanella oneidensis. The µ-scale biological fuel cell introduces the necessary small size and fuel flexibility for applications in vivo and in situ sensors which may be remotely deployed and self-powered.

  9. Solid waste electrical generating feasibility study

    SciTech Connect

    Not Available

    1982-05-01

    The feasibility of recommissioning the existing 3 megawatt steam turbine driven electrical generator of the Municipal Utilities of Valley City, North Dakota, using steam generated in a new facility from the incineration of municipal solid waste generated in the area is examined. It is concluded that (1) there is sufficient municipal solid waste that can be obtained from Valley City, Moorhead and Jamestown (and/or West Fargo) to fuel the plant; (2) the seasonal fluctuation in the amounts of municipal solid waste indicates that a supplementary source of fuel for use during winter would increase plant efficiency; (3) the probable capital cost of the project will be $3,590,000.00; (4) the cost of production of electricity could range from 3.72 cents/kWh to 4.90 cents/kWh, depending on the construction costs, interest rate, lifetime of the project, availability for the plant and steam produced per ton of municipal solid waste; (5) there is no compelling reason why the tertiary cell of the sewage lagoon, cannot be used for cooling water; (6) the State Health Department is ambivalent toward the project; and (7) the public perception of the project is positive. 92 references.

  10. Third Generation Flywheels for electric storage

    SciTech Connect

    Ricci, Michael, R.; Fiske, O. James

    2008-02-29

    Electricity is critical to our economy, but growth in demand has saturated the power grid causing instability and blackouts. The economic penalty due to lost productivity in the US exceeds $100 billion per year. Opposition to new transmission lines and power plants, environmental restrictions, and an expected $100 billion grid upgrade cost have slowed system improvements. Flywheel electricity storage could provide a more economical, environmentally benign alternative and slash economic losses if units could be scaled up in a cost effective manner to much larger power and capacity than the present maximum of a few hundred kW and a few kWh per flywheel. The goal of this project is to design, construct, and demonstrate a small-scale third generation electricity storage flywheel using a revolutionary architecture scalable to megawatt-hours per unit. First generation flywheels are built from bulk materials such as steel and provide inertia to smooth the motion of mechanical devices such as engines. They can be scaled up to tens of tons or more, but have relatively low energy storage density. Second generation flywheels use similar designs but are fabricated with composite materials such as carbon fiber and epoxy. They are capable of much higher energy storage density but cannot economically be built larger than a few kWh of storage capacity due to structural and stability limitations. LaunchPoint is developing a third generation flywheel — the "Power Ring" — with energy densities as high or higher than second generation flywheels and a totally new architecture scalable to enormous sizes. Electricity storage capacities exceeding 5 megawatt-hours per unit appear both technically feasible and economically attractive. Our design uses a new class of magnetic bearing – a radial gap “shear-force levitator” – that we discovered and patented, and a thin-walled composite hoop rotated at high speed to store kinetic energy. One immediate application is power grid

  11. 78 FR 4873 - Electrical Protective Equipment Standard and the Electric Power Generation, Transmission, and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-01-23

    ... Occupational Safety and Health Administration Electrical Protective Equipment Standard and the Electric Power... on Electrical Protective Equipment (29 CFR 1910.137) and Electric Power Generation, Transmission, and... Equipment Standard (29 CFR 1910.137) and the Electric Power Generation, Transmission, and...

  12. Primary electric power generation systems for advanced-technology engines

    NASA Technical Reports Server (NTRS)

    Cronin, M. J.

    1983-01-01

    The advantages of the all electric airplane are discussed. In the all electric airplane the generator is the sole source of electric power; it powers the primary and secondary flight controls, the environmentals, and the landing gear. Five candidates for all electric power systems are discussed and compared. Cost benefits of the all electric airplane are discussed.

  13. 78 FR 36277 - Vogtle Electric Generating Plant, Unit 3

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-06-17

    ... COMMISSION Vogtle Electric Generating Plant, Unit 3 AGENCY: Nuclear Regulatory Commission. ACTION..., and Acceptance Criteria (ITAAC) E.2.5.04.05.05.01, for the Vogtle Electric Generating Plant, Unit 3... Vogtle Electric Generating Plant, Unit 3 ] (ADAMS Accession No. ML13032A592). This ITAAC was approved...

  14. Electrical Generating Capacities of Geothermal Slim Holes

    SciTech Connect

    Pritchett, J.W.

    1998-10-01

    Theoretical calculations are presented to estimate the electrical generating capacity of the hot fluids discharged from individual geothermal wells using small wellhead generating equipment over a wide range of reservoir and operating conditions. The purpose is to appraise the possibility of employing slim holes (instead of conventional production-size wells) to power such generators for remote off-grid applications such as rural electrification in developing countries. Frequently, the generating capacity desired is less than one megawatt, and can be as low as 100 kilowatts; if slim holes can be usefully employed, overall project costs will be significantly reduced. This report presents the final results of the study. Both self-discharging wells and wells equipped with downhole pumps (either of the ''lineshaft'' or the ''submersible'' type) are examined. Several power plant designs are considered, including conventional single-flash backpressure and condensing steam turbines, binary plants, double-flash steam plants, and steam turbine/binary hybrid designs. Well inside diameters from 75 mm to 300 mm are considered; well depths vary from 300 to 1200 meters. Reservoir temperatures from 100 C to 240 C are examined, as are a variety of reservoir pressures and CO2 contents and well productivity index values.

  15. Vogtle Electric Generating Plant ETE Analysis Review

    SciTech Connect

    Diediker, Nona H.; Jones, Joe A.

    2006-12-09

    Under contract with the Nuclear Regulatory Commission (NRC), staff from Pacific Northwest National Laboratory (PNNL) and Sandia National Laboratory (SNL)-Albuquerque reviewed the evacuation time estimate (ETE) analysis dated April 2006 prepared by IEM for the Vogtle Electric Generating Plant (VEGP). The ETE analysis was reviewed for consistency with federal regulations using the NRC guidelines in Review Standard (RS)-002, Supplement 2 and Appendix 4 to NUREG-0654, and NUREG/CR-4831. Additional sources of information referenced in the analysis and used in the review included NUREG/CR-6863 and NUREG/CR-6864. The PNNL report includes general comments, data needs or clarifications, and requests for additional information (RAI) resulting from review of the ETE analysis.

  16. SNAP-8 electrical generating system development program

    NASA Technical Reports Server (NTRS)

    1971-01-01

    The SNAP-8 program has developed the technology base for one class of multikilowatt dynamic space power systems. Electrical power is generated by a turbine-alternator in a mercury Rankine-cycle loop to which heat is transferred and removed by means of sodium-potassium eutectic alloy subsystems. Final system overall criteria include a five-year operating life, restartability, man rating, and deliverable power in the 90 kWe range. The basic technology was demonstrated by more than 400,000 hours of major component endurance testing and numerous startup and shutdown cycles. A test system, comprised of developed components, delivered up to 35 kWe for a period exceeding 12,000 hours. The SNAP-8 system baseline is considered to have achieved a level of technology suitable for final application development for long-term multikilowatt space missions.

  17. 1. GENERAL VIEW OF FISK STREET ELECTRIC GENERATING STATION COMPLEX, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. GENERAL VIEW OF FISK STREET ELECTRIC GENERATING STATION COMPLEX, LOOKING SOUTH; IN THE CENTER, BEHIND THE STACK IS THE GENERATING STATION BUILT IN 1959; THE TALL METAL-CLAD BUILDING CONTAINS A COAL BUNKER, COAL PULVERIZER, FURNACE, BOILER, SUPER-HEATER, STEAM PIPES, AND HOT-AIR DUCTS. TO THE RIGHT OF THIS 1959 GENERATING STATION IS THE ORIGINAL POWERHOUSE. - Commonwealth Electric Company, Fisk Street Electrical Generating Station, 1111 West Cermak Avenue, Chicago, Cook County, IL

  18. 18 CFR 801.12 - Electric power generation.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 18 Conservation of Power and Water Resources 2 2011-04-01 2011-04-01 false Electric power... COMMISSION GENERAL POLICIES § 801.12 Electric power generation. (a) Significant uses are presently being made of the waters of the basin for the generation of electric power at hydro, pumped storage,...

  19. 18 CFR 801.12 - Electric power generation.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 18 Conservation of Power and Water Resources 2 2010-04-01 2010-04-01 false Electric power... COMMISSION GENERAL POLICIES § 801.12 Electric power generation. (a) Significant uses are presently being made of the waters of the basin for the generation of electric power at hydro, pumped storage,...

  20. Reliability impact of solar electric generation upon electric utility systems

    NASA Astrophysics Data System (ADS)

    Day, J. T.; Hobbs, W. J.

    1982-08-01

    The introduction of solar electric systems into an electric utility grid brings new considerations in the assessment of the utility's power supply reliability. This paper summarizes a methodology for estimating the reliability impact of solar electric technologies upon electric utilities for value assessment and planning purposes. Utility expansion and operating impacts are considered. Sample results from photovoltaic analysis show that solar electric plants can increase the reliable load-carrying capability of a utility system. However, the load-carrying capability of the incremental power tends to decrease, particularly at significant capacity penetration levels. Other factors influencing reliability impact are identified.

  1. Continuous overnight observation of human premolar eruption.

    PubMed

    Risinger, R K; Proffit, W R

    1996-01-01

    Such observation was made possible by transmitting the image of a mobile ceramic ruling on the erupting maxillary second premolar to a video-microscope via a coaxial fibreoptic cable. The cable was inserted into a reference bar secured to the adjacent first molar and first premolar. The image of the ruling was superimposed with the image from a surveillance camera focused on the patient and continuously recorded on video-tape along with the participant's blood pressure, pulse rate, electromyographic activity and occlusal contact sounds. Overnight data from 12 individuals clearly revealed a circadian rhythm in eruption during the prefunctional spurt. On average, the maxillary second premolar erupted 41 microns during an 11-h overnight observation, with almost all the eruption occurring in the late evening from 8 p.m. to 1 a.m. After 1 a.m., eruption typically ceased, with a tendency for intrusion to occur until 7 a.m. Sleep increased the rate of eruption during the late evening, but did not influence the eruption rate during the early morning. Haemodynamic changes, including blood pressure and pulse rate, did not have a significant impact on the rhythm of eruption. The observed eruption rhythm is most probably caused by changing hormone levels and their effect on the periodontal ligament. The late-evening eruption of human premolars coincides with the late-evening secretion of growth hormone and thyroid hormone typically found in humans. PMID:9022915

  2. Rotary-Atomizer Electric Power Generator

    NASA Astrophysics Data System (ADS)

    Nguyen, Trieu; Tran, Tuan; de Boer, Hans; van den Berg, Albert; Eijkel, Jan C. T.

    2015-03-01

    We report experimental and theoretical results on a ballistic energy-conversion method based on a rotary atomizer working with a droplet acceleration-deceleration cycle. In a rotary atomizer, liquid is fed onto the center of a rotating flat surface, where it spreads out under the action of the centrifugal force and creates "atomized" droplets at its edge. The advantage of using a rotary atomizer is that the centrifugal force exerted on the fluid on a smooth, large surface is not only a robust form of acceleration, as it avoids clogging, but also easily allows high throughput, and produces high electrical power. We successfully demonstrate an output power of 4.9 mW and a high voltage up to 3120 V. At present, the efficiency of the system is still low (0.14%). However, the conversion mechanism of the system is fully interpreted in this paper, permitting a conceptual understanding of system operation and providing a roadmap for system optimization. This observation will open up a road for building power-generation systems in the near future.

  3. Integrated engine-generator concept for aircraft electric secondary power

    NASA Technical Reports Server (NTRS)

    Secunde, R. R.; Macosko, R. P.; Repas, D. S.

    1972-01-01

    The integrated engine-generator concept of locating an electric generator inside an aircraft turbojet or turbofan engine concentric with, and driven by, one of the main engine shafts is discussed. When properly rated, the generator can serve as an engine starter as well as a generator of electric power. The electric power conversion equipment and generator controls are conveniently located in the aircraft. Preliminary layouts of generators in a large engine together with their physical sizes and weights indicate that this concept is a technically feasible approach to aircraft secondary power.

  4. Interior room within eastern lift span, showing auxiliary electric generator. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Interior room within eastern lift span, showing auxiliary electric generator. - Arlington Memorial Bridge, Spanning Potomac River between Lincoln Memorial & Arlington National Cemetery, Washington, District of Columbia, DC

  5. The General Electric MOD-1 wind turbine generator program

    NASA Technical Reports Server (NTRS)

    Poor, R. H.; Hobbs, R. B.

    1979-01-01

    The design, fabrication, installation and checkout of MOD-1, a megawatt class wind turbine generator which generates utility grade electrical power, is described. A MOD-1/MOD-1A tradeoff study is discussed.

  6. Global potential for wind-generated electricity

    PubMed Central

    Lu, Xi; McElroy, Michael B.; Kiviluoma, Juha

    2009-01-01

    The potential of wind power as a global source of electricity is assessed by using winds derived through assimilation of data from a variety of meteorological sources. The analysis indicates that a network of land-based 2.5-megawatt (MW) turbines restricted to nonforested, ice-free, nonurban areas operating at as little as 20% of their rated capacity could supply >40 times current worldwide consumption of electricity, >5 times total global use of energy in all forms. Resources in the contiguous United States, specifically in the central plain states, could accommodate as much as 16 times total current demand for electricity in the United States. Estimates are given also for quantities of electricity that could be obtained by using a network of 3.6-MW turbines deployed in ocean waters with depths <200 m within 50 nautical miles (92.6 km) of closest coastlines. PMID:19549865

  7. Global potential for wind-generated electricity.

    PubMed

    Lu, Xi; McElroy, Michael B; Kiviluoma, Juha

    2009-07-01

    The potential of wind power as a global source of electricity is assessed by using winds derived through assimilation of data from a variety of meteorological sources. The analysis indicates that a network of land-based 2.5-megawatt (MW) turbines restricted to nonforested, ice-free, nonurban areas operating at as little as 20% of their rated capacity could supply >40 times current worldwide consumption of electricity, >5 times total global use of energy in all forms. Resources in the contiguous United States, specifically in the central plain states, could accommodate as much as 16 times total current demand for electricity in the United States. Estimates are given also for quantities of electricity that could be obtained by using a network of 3.6-MW turbines deployed in ocean waters with depths <200 m within 50 nautical miles (92.6 km) of closest coastlines.

  8. Electricity generation choices for the near term.

    PubMed

    Bodansky, D

    1980-02-15

    Electricity demand is expected to increase during the next few decades, especially if it is accepted that the primary goal of energy conservation is to reduce oil consumption. Although the renewable resources in principle have unlimited potential, it is not clear that they can make a major contribution to electricity expansion within the 20th century. Coal and nuclear power are the practical alternatives. The adverse effects of nuclear power probably remain less than those of coal, despite the impact of the Three Mile Island accident. It is important to explore and exploit all options, especially the endangered nuclear option. PMID:17795990

  9. Electrical effects generated by experimental volcanic explosions

    SciTech Connect

    Buettner, R.; Roeder, H.; Zimanowski, B.

    1997-04-01

    We report on the experimental study of electrical phenomena during explosive volcanic eruptions, which provides qualitative and quantitative insight into different fragmentation and eruption mechanisms of magmatic melt. The experiments show that air friction and surface enlargement by hydro- and/or aerodynamic magma fragmentation are only minor contributors to electrical charging of erupted particle clouds in comparison to thermo-hydraulic fracturing of magma by explosive magma/water interaction. This process has the potency to explain the frequently observed occurrence of lightning in eruption clouds of explosive volcanic events. {copyright} {ital 1997 American Institute of Physics.}

  10. Voltaic turbine - A paradigm shift proposed in generating electricity

    NASA Astrophysics Data System (ADS)

    V, Meera

    2013-12-01

    Sustainable demand for electric power results in a warehouse that naturally favors development of wind turbines that are significantly quieter and more efficient for generating electricity than today's fleet. Achieving this will require a revolutionary new concept, in particular "Magneto Voltaic Power plant" that generate electricity with the help of repulsive force which cause the turbine blades to rotate. The magneto voltaic power plant triggered the original development of wind turbines raising its energy and output power. This paper outlines the main issues involved in replacing the wind source to that of the repulsive force. It's shown that implementation of repulsive force generates electric power at a feasible cost and this would clearly be the enabling technology for generating electricity of the future.

  11. An experimental electrical generating unit using sugarcane bagasse as fuel

    SciTech Connect

    Elkoury, J.M.

    1980-12-01

    The purpose of this paper is to present the alternatives that exist within the Puerto Rico Electric Power Authority to develop an experimental electrical generating unit which would use sugarcane bagasse as fuel. The study includes a comparison between the sugarcane bagasse and other fuels, the location of an experimental electrical generating unit with respect to the sugarcane fields, the transportation of the bagasse and the generating equipment available for this project in terms of its fisical condition. This latter part would include any modifications in the equipment which we would have to undertake in order to carry out the study.

  12. Electricity generation modeling and photovoltaic forecasts in China

    NASA Astrophysics Data System (ADS)

    Li, Shengnan

    With the economic development of China, the demand for electricity generation is rapidly increasing. To explain electricity generation, we use gross GDP, the ratio of urban population to rural population, the average per capita income of urban residents, the electricity price for industry in Beijing, and the policy shift that took place in China. Ordinary least squares (OLS) is used to develop a model for the 1979--2009 period. During the process of designing the model, econometric methods are used to test and develop the model. The final model is used to forecast total electricity generation and assess the possible role of photovoltaic generation. Due to the high demand for resources and serious environmental problems, China is pushing to develop the photovoltaic industry. The system price of PV is falling; therefore, photovoltaics may be competitive in the future.

  13. Storing the Electric Energy Produced by an AC Generator

    ERIC Educational Resources Information Center

    Carvalho, P. Simeao; Lima, Ana Paula; Carvalho, Pedro Simeao

    2010-01-01

    Producing energy from renewable energy sources is nowadays a priority in our society. In many cases this energy comes as electric energy, and when we think about electric energy generators, one major issue is how we can store that energy. In this paper we discuss how this can be done and give some ideas for applications that can serve as a…

  14. Liquefied natural gas-freon electricity generation system

    SciTech Connect

    Nozawa, R.

    1983-12-27

    The present invention relates to an electricity generation system, using freon as an agent to circulate between a warm heat source and a cold heat sink, recapturing electrical energy on one side and alleviating thermal pollution in the environment on the other side.

  15. Liquefied natural gas-freon electricity generation system

    SciTech Connect

    Nozawa, R.

    1982-05-25

    The present invention relates to an electricity generation system, using freon as an agent to circulate between a warm heat source and a cold heat sink, recapturing electrical energy on one side and alleviating thermal pollution in the environment on the other side.

  16. The Environmental Impact of Electrical Power Generation: Nuclear and Fossil.

    ERIC Educational Resources Information Center

    Pennsylvania State Dept. of Education, Harrisburg.

    This text was written to accompany a course concerning the need, environmental costs, and benefits of electrical power generation. It was compiled and written by a committee drawn from educators, health physicists, members of industry and conservation groups, and environmental scientists. Topics include: the increasing need for electrical power,…

  17. Evaluation of biomass systems for electricity generation. Final report

    SciTech Connect

    Lipinsky, E.S.; Ball, D.A.; Anson, D.

    1982-02-01

    State-of-the-art information and evaluation of alternative biomass systems for generation of electricity are provided. The biomass systems consist of silvicultural or agricultural resources, processing and conversion technology to make biomass-derived fuels, and electricity-generating technology. The systems are delineated in energy network charts and are evaluated in matrices that display biomass-system alternatives and multiple technical, economic, and environmental-impact criteria.

  18. Spin generation by strong inhomogeneous electric fields

    NASA Astrophysics Data System (ADS)

    Finkler, Ilya; Engel, Hans-Andreas; Rashba, Emmanuel; Halperin, Bertrand

    2007-03-01

    Motivated by recent experiments [1], we propose a model with extrinsic spin-orbit interaction, where an inhomogeneous electric field E in the x-y plane can give rise, through nonlinear effects, to a spin polarization with non-zero sz, away from the sample boundaries. The field E induces a spin current js^z= z x(αjc+βE), where jc=σE is the charge current, and the two terms represent,respectively, the skew scattering and side-jump contributions. [2]. The coefficients α and β are assumed to be E- independent, but conductivity σ is field dependent. We find the spin density sz by solving the equation for spin diffusion and relaxation with a source term ∇.js^z. For sufficiently low fields, jc is linear in E, and the source term vanishes, implying that sz=0 away from the edges. However, for large fields, σ varies with E. Solving the diffusion equation in a T-shaped geometry, where the electric current propagates along the main channel, we find spin accumulation near the entrance of the side channel, similar to experimental findings [1]. Also, we present a toy model where spin accumulation away from the boundary results from a nonlinear and anisotropic conductivity. [1] V. Sih, et al, Phys. Rev. Lett. 97, 096605 (2006). [2] H.-A. Engel, B.I. Halperin, E.I.Rashba, Phys. Rev. Lett. 95, 166605 (2005).

  19. Heat-operated cryogenic electrical generator

    NASA Technical Reports Server (NTRS)

    Wang, T. G.; Saffren, M. M.; Elleman, D. D.

    1975-01-01

    Generator operation is based upon unusual hydrodynamic properties exhibited by liquid helium below superfluid critical point. Below that temperature, liquid behaves as though it is mixture of two interpenetrating fluids. When transition takes place between superfluid and normal states, conservation of momentum is always balanced by normal fluid.

  20. Guide for the assessment of technologies for generating electricity

    SciTech Connect

    Not Available

    1982-06-01

    This guide provides a general understanding of electric power generation, places each technology in perspective with regard to other technologies, refers the reader to supplementary and more detailed information, and provides a framework for future updating of data bases maintained by EIA. The guide includes information on already commercialized technologies for generating electricity and technologies that have not moved beyond the prototype or demonstration state. It does not, however, include nuclear technologies or cogeneration, and does not discuss the fuel costs associated with producing electricity by each technology.

  1. The overnight effect on the Taiwan stock market

    NASA Astrophysics Data System (ADS)

    Tsai, Kuo-Ting; Lih, Jiann-Shing; Ko, Jing-Yuan

    2012-12-01

    This study examines statistical regularities among three components of stocks and indices: daytime (trading hour) return, overnight (off-hour session) return, and total (close-to-close) return. Owing to the fact that the Taiwan Stock Exchange (TWSE) has the longest non-trading periods among major markets, the TWSE is selected to explore the correlation among the three components and compare it with major markets such as the New York Stock Exchange (NYSE) and the National Association of Securities Dealers Automated Quotation (NASDAQ). Analysis results indicate a negative cross correlation between the sign of daytime return and the sign of overnight return; possibly explaining why most stocks feature a negative cross correlation between daytime return and overnight return [F. Wang, S.-J. Shieh, S. Havlin, H.E. Stanley, Statistical analysis of the overnight and daytime return, Phys. Rev. E 79 (2009) 056109]. Additionally, the cross correlation between the magnitude of returns is analyzed. According to those results, a larger magnitude of overnight return implies a higher probability that the sign of the following daytime return is the opposite of the sign of overnight return. Namely, the predictability of daytime return might be improved when a stock undergoes a large magnitude of overnight return. Furthermore, the cross correlations of 29 indices of worldwide markets are discussed.

  2. Role of Energy Storage with Renewable Electricity Generation

    SciTech Connect

    Denholm, P.; Ela, E.; Kirby, B.; Milligan, M.

    2010-01-01

    Renewable energy sources, such as wind and solar, have vast potential to reduce dependence on fossil fuels and greenhouse gas emissions in the electric sector. Climate change concerns, state initiatives including renewable portfolio standards, and consumer efforts are resulting in increased deployments of both technologies. Both solar photovoltaics (PV) and wind energy have variable and uncertain (sometimes referred to as intermittent) output, which are unlike the dispatchable sources used for the majority of electricity generation in the United States. The variability of these sources has led to concerns regarding the reliability of an electric grid that derives a large fraction of its energy from these sources as well as the cost of reliably integrating large amounts of variable generation into the electric grid. In this report, we explore the role of energy storage in the electricity grid, focusing on the effects of large-scale deployment of variable renewable sources (primarily wind and solar energy).

  3. Electric-arc steam plasma generator

    NASA Astrophysics Data System (ADS)

    Anshakov, A. S.; Urbakh, E. K.; Radko, S. I.; Urbakh, A. E.; Faleev, V. A.

    2015-01-01

    Investigation results on the arc plasmatorch for water-steam heating are presented. The construction arrangement of steam plasma generator with copper electrodes of the stepped geometry was firstly implemented. The energy characteristics of plasmatorch and erosion of electrodes reflect the features of their behavior at arc glow in the plasma-forming environment of steam. The results of numerical study of the thermal state of the composite copper-steel electrodes had a significant influence on optimization of anode water-cooling aimed at improvement of its operation life.

  4. Solar powered Stirling cycle electrical generator

    NASA Technical Reports Server (NTRS)

    Shaltens, Richard K.

    1991-01-01

    Under NASA's Civil Space Technology Initiative (CSTI), the NASA Lewis Research Center is developing the technology needed for free-piston Stirling engines as a candidate power source for space systems in the late 1990's and into the next century. Space power requirements include high efficiency, very long life, high reliability, and low vibration. Furthermore, system weight and operating temperature are important. The free-piston Stirling engine has the potential for a highly reliable engine with long life because it has only a few moving parts, non-contacting gas bearings, and can be hermetically sealed. These attributes of the free-piston Stirling engine also make it a viable candidate for terrestrial applications. In cooperation with the Department of Energy, system designs are currently being completed that feature the free-piston Stirling engine for terrestrial applications. Industry teams were assembled and are currently completing designs for two Advanced Stirling Conversion Systems utilizing technology being developed under the NASA CSTI Program. These systems, when coupled with a parabolic mirror to collect the solar energy, are capable of producing about 25 kW of electricity to a utility grid. Industry has identified a niche market for dish Stirling systems for worldwide remote power application. They believe that these niche markets may play a major role in the introduction of Stirling products into the commercial market.

  5. Electrical power generation from salinity gradients using pressure retarded osmosis

    SciTech Connect

    Emery, A.F.; Yourstone, W.H.

    1983-08-01

    The use of a pressure retarded osmosis system (PRO) to generate electricity form naturally available or artificially generated salt is described. Variations in overall system efficiency are analyzed in terms of freshwater and brine flow rates, fluid pressure levels, and membrane permeability. It is shown that the PRO system is economically competitive with other alternative energy systems.

  6. Distributed electrical generation technologies and methods for their economic assessment

    SciTech Connect

    Kreider, J.F.; Curtiss, P.S.

    2000-07-01

    A confluence of events in the electrical generation and transmission industry has produced a new paradigm for distributed electrical generation and distribution in the US Electrical deregulation, reluctance of traditional utilities to commit capital to large central plants and transmission lines, and a suite of new, efficient generation hardware have all combined to bring this about. Persistent environmental concerns have further stimulated several new approaches. In this paper the authors describe the near term distributed generation technologies and their differentiating characteristics along with their readiness for the US market. In order to decide which approaches are well suited to a specific project, an assessment methodology is needed. A technically sound approach is therefore described and example results are given.

  7. Solar electricity supply isolines of generation capacity and storage

    PubMed Central

    Grossmann, Wolf; Grossmann, Iris; Steininger, Karl W.

    2015-01-01

    The recent sharp drop in the cost of photovoltaic (PV) electricity generation accompanied by globally rapidly increasing investment in PV plants calls for new planning and management tools for large-scale distributed solar networks. Of major importance are methods to overcome intermittency of solar electricity, i.e., to provide dispatchable electricity at minimal costs. We find that pairs of electricity generation capacity G and storage S that give dispatchable electricity and are minimal with respect to S for a given G exhibit a smooth relationship of mutual substitutability between G and S. These isolines between G and S support the solving of several tasks, including the optimal sizing of generation capacity and storage, optimal siting of solar parks, optimal connections of solar parks across time zones for minimizing intermittency, and management of storage in situations of far below average insolation to provide dispatchable electricity. G−S isolines allow determining the cost-optimal pair (G,S) as a function of the cost ratio of G and S. G−S isolines provide a method for evaluating the effect of geographic spread and time zone coverage on costs of solar electricity. PMID:25755261

  8. Solar electricity supply isolines of generation capacity and storage.

    PubMed

    Grossmann, Wolf; Grossmann, Iris; Steininger, Karl W

    2015-03-24

    The recent sharp drop in the cost of photovoltaic (PV) electricity generation accompanied by globally rapidly increasing investment in PV plants calls for new planning and management tools for large-scale distributed solar networks. Of major importance are methods to overcome intermittency of solar electricity, i.e., to provide dispatchable electricity at minimal costs. We find that pairs of electricity generation capacity G and storage S that give dispatchable electricity and are minimal with respect to S for a given G exhibit a smooth relationship of mutual substitutability between G and S. These isolines between G and S support the solving of several tasks, including the optimal sizing of generation capacity and storage, optimal siting of solar parks, optimal connections of solar parks across time zones for minimizing intermittency, and management of storage in situations of far below average insolation to provide dispatchable electricity. G-S isolines allow determining the cost-optimal pair (G,S) as a function of the cost ratio of G and S. G-S isolines provide a method for evaluating the effect of geographic spread and time zone coverage on costs of solar electricity.

  9. Application of field-modulated generator systems to dispersed solar thermal electric generation

    NASA Technical Reports Server (NTRS)

    Ramakumar, R.

    1979-01-01

    The state-of-the-art of field modulated generation system (FMGS) is presented, and the application of FMGS to dispersed solar thermal electric generation is discussed. The control and monitoring requirements for solar generation system are defined. A comparison is presented between the FMGS approach and other options and the technological development needs are discussed.

  10. The energetics of electric organ discharge generation in gymnotiform weakly electric fish.

    PubMed

    Salazar, Vielka L; Krahe, Rüdiger; Lewis, John E

    2013-07-01

    Gymnotiform weakly electric fish produce an electric signal to sense their environment and communicate with conspecifics. Although the generation of such relatively large electric signals over an entire lifetime is expected to be energetically costly, supporting evidence to date is equivocal. In this article, we first provide a theoretical analysis of the energy budget underlying signal production. Our analysis suggests that wave-type and pulse-type species invest a similar fraction of metabolic resources into electric signal generation, supporting previous evidence of a trade-off between signal amplitude and frequency. We then consider a comparative and evolutionary framework in which to interpret and guide future studies. We suggest that species differences in signal generation and plasticity, when considered in an energetics context, will not only help to evaluate the role of energetic constraints in the evolution of signal diversity but also lead to important general insights into the energetics of bioelectric signal generation.

  11. Fresh look at electric-generating reserve margins

    SciTech Connect

    Franklin, E.H.

    1983-04-28

    In recent years, public attention has focused on electric-generating reserve margins as barometers of electric-power cost and service reliability. This article argues that the current definition, based on peak demand, overstates actual reserve capacity and therefore contributes to the perception that reserve margins are excessive. A new definition based on available installed capacity is proposed as a more-precise representation of the system condition. 6 figures.

  12. Electrically controlled nonlinear generation of light with plasmonics.

    PubMed

    Cai, Wenshan; Vasudev, Alok P; Brongersma, Mark L

    2011-09-23

    Plasmonics provides a route to develop ultracompact optical devices on a chip by using extreme light concentration and the ability to perform simultaneous electrical and optical functions. These properties also make plasmonics an ideal candidate for dynamically controlling nonlinear optical interactions at the nanoscale. We demonstrate electrically tunable harmonic generation of light from a plasmonic nanocavity filled with a nonlinear medium. The metals that define the cavity also serve as electrodes that can generate high direct current electric fields across the nonlinear material. A fundamental wave at 1.56 micrometers was frequency doubled and modulated in intensity by applying a moderate external voltage to the electrodes, yielding a voltage-dependent nonlinear generation with a normalized magnitude of ~7% per volt.

  13. Vascular effects of free radicals generated by electrical stimulation

    SciTech Connect

    Lamb, F.S.; Webb, R.C.

    1984-11-01

    Electrical field stimulation (9 V, 1.0 ms, 4 Hz) of isolated segments of rat tail arteries and dog coronary arteries inhibits contractile response to exogenous norephinephrine and elevated potassium concentration. This inhibitory effect of electrical stimulation is blocked by various agents that alter oxygen metabolism: superoxide dismutase, catalase, glutathione, ascorbate, and dimethyl sulfoxide. The observations suggest that the inhibitory effect is due to an action of oxygen free radical metabolites that are generated by the electrical stimulation of the oxygen-rich buffer. These free radical metabolites have two actions: 1) they oxidize drugs in the experimental system, and 2) they exert a direct inhbitory action on vascular smooth muscle.

  14. Microneedle array for measuring wound generated electric fields.

    PubMed

    Mukerjee, E V; Isseroff, R R; Nuccitelli, R; Collins, S D; Smith, R L

    2006-01-01

    A microneedle array has been fabricated and applied to the measurement of transdermal skin potentials in human subjects. Potential changes were recorded in the vicinity of superficial wounds, confirming the generation of a lateral electric field in human skin. The measured electric field decays with distance from the wound edge, and is directed towards the wound. The measurement of endogenous fields in skin is a prelude to the study of the therapeutic efficacy of applied electric fields to chronic non-healing wounds. PMID:17947077

  15. Road electric generation system with use of solar power

    SciTech Connect

    Meiarashi, S.; Ohara, Toshimasa

    1997-09-01

    The temperature of road pavement surface becomes more than 70 C because of the solar power in summer. The characteristics of asphalt pavement on heat transfer and the relatively huge occupation with urban area have caused the heat-island phenomena. The phenomena increase the temperature and the energy consumption for conditioners. Road administrators have to keep the road pavement surface out of freezing in winter. For the purpose, the use of dusting powder becomes popular in recent days. However, the negative influence of the huge amount of the powder could not be ignored, for instance, corrosion of steel bridge and cars, water pollution, and soil pollution. Another way is a road heating system. The enormous electric energy consumption prevents the system from becoming popular. The authors have devised the new system that generates electric power and works as a road heating system. The authors call the system as ``Road Electric Generation System (REGS).`` The basic principal of the electric generation and road heating is Seebeck and Pertier effect, respectively. In this paper, the authors have calculated the electric power generated by the system, road surface temperature after introducing the system, and the heat radiation from the road surface.

  16. Dispersed solar thermal generation employing parabolic dish-electric transport with field modulated generator systems

    NASA Technical Reports Server (NTRS)

    Ramakumar, R.; Bahrami, K.

    1981-01-01

    This paper discusses the application of field modulated generator systems (FMGS) to dispersed solar-thermal-electric generation from a parabolic dish field with electric transport. Each solar generation unit is rated at 15 kWe and the power generated by an array of such units is electrically collected for insertion into an existing utility grid. Such an approach appears to be most suitable when the heat engine rotational speeds are high (greater than 6000 r/min) and, in particular, if they are operated in the variable speed mode and if utility-grade a.c. is required for direct insertion into the grid without an intermediate electric energy storage and reconversion system. Predictions of overall efficiencies based on conservative efficiency figures for the FMGS are in the range of 25 per cent and should be encouraging to those involved in the development of cost-effective dispersed solar thermal power systems.

  17. Development of a linear piston-type pulse power electric generator for powering electric guns

    NASA Astrophysics Data System (ADS)

    Summerfield, Martin

    1993-01-01

    The development of a linear piston-type electric pulse-power generator capable of powering electric guns and EM (rail and coil) guns and ET guns, presently under development, is discussed. The pulse-power generator consists of a cylindrical armature pushed by gases from the combustion of fuel or propellant through an externally produced magnetic field. An arrangement of electrodes and connecting straps serves to extract current from the moving armature and to send it to an external load (the electric gun).

  18. Life Cycle Greenhouse Gas Emissions from Electricity Generation (Fact Sheet)

    SciTech Connect

    Not Available

    2013-01-01

    Analysts at NREL have developed and applied a systematic approach to review the LCA literature, identify primary sources of variability and, where possible, reduce variability in GHG emissions estimates through a procedure called 'harmonization.' Harmonization of the literature provides increased precision and helps clarify the impacts of specific electricity generation choices, producing more robust results.

  19. Clean coal technologies in electric power generation: a brief overview

    SciTech Connect

    Janos Beer; Karen Obenshain

    2006-07-15

    The paper talks about the future clean coal technologies in electric power generation, including pulverized coal (e.g., advanced supercritical and ultra-supercritical cycles and fluidized-bed combustion), integrated gasification combined cycle (IGCC), and CO{sub 2} capture technologies. 6 refs., 2 tabs.

  20. Distributed Generation Dispatch Optimization under VariousElectricity Tariffs

    SciTech Connect

    Firestone, Ryan; Marnay, Chris

    2007-05-01

    The on-site generation of electricity can offer buildingowners and occupiers financial benefits as well as social benefits suchas reduced grid congestion, improved energy efficiency, and reducedgreenhouse gas emissions. Combined heat and power (CHP), or cogeneration,systems make use of the waste heat from the generator for site heatingneeds. Real-time optimal dispatch of CHP systems is difficult todetermine because of complicated electricity tariffs and uncertainty inCHP equipment availability, energy prices, and system loads. Typically,CHP systems use simple heuristic control strategies. This paper describesa method of determining optimal control in real-time and applies it to alight industrial site in San Diego, California, to examine: 1) the addedbenefit of optimal over heuristic controls, 2) the price elasticity ofthe system, and 3) the site-attributable greenhouse gas emissions, allunder three different tariff structures. Results suggest that heuristiccontrols are adequate under the current tariff structure and relativelyhigh electricity prices, capturing 97 percent of the value of thedistributed generation system. Even more value could be captured bysimply not running the CHP system during times of unusually high naturalgas prices. Under hypothetical real-time pricing of electricity,heuristic controls would capture only 70 percent of the value ofdistributed generation.

  1. The Environmental Impact of Electrical Generation: Nuclear vs. Conventional.

    ERIC Educational Resources Information Center

    McDermott, John J., Ed.

    This minicourse, partially supported by the Division of Nuclear Education and Training of the U.S. Atomic Energy Commission, is an effort to describe the benefit-to-risk ratio of various methods of generating electrical power. It attempts to present an unbiased, straightforward, and objective view of the advantages and disadvantages of nuclear…

  2. Modeling Distributed Electricity Generation in the NEMS Buildings Models

    EIA Publications

    2011-01-01

    This paper presents the modeling methodology, projected market penetration, and impact of distributed generation with respect to offsetting future electricity needs and carbon dioxide emissions in the residential and commercial buildings sector in the Annual Energy Outlook 2000 (AEO2000) reference case.

  3. 18 CFR 801.12 - Electric power generation.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 18 Conservation of Power and Water Resources 2 2012-04-01 2012-04-01 false Electric power generation. 801.12 Section 801.12 Conservation of Power and Water Resources SUSQUEHANNA RIVER BASIN... located either in the basin or nearby its borders. (b) There appears to be limited site potential in...

  4. 18 CFR 801.12 - Electric power generation.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 18 Conservation of Power and Water Resources 2 2014-04-01 2014-04-01 false Electric power generation. 801.12 Section 801.12 Conservation of Power and Water Resources SUSQUEHANNA RIVER BASIN... located either in the basin or nearby its borders. (b) There appears to be limited site potential in...

  5. 18 CFR 801.12 - Electric power generation.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 18 Conservation of Power and Water Resources 2 2013-04-01 2012-04-01 true Electric power generation. 801.12 Section 801.12 Conservation of Power and Water Resources SUSQUEHANNA RIVER BASIN... located either in the basin or nearby its borders. (b) There appears to be limited site potential in...

  6. Generation of strong electric fields in an ice film capacitor

    NASA Astrophysics Data System (ADS)

    Shin, Sunghwan; Kim, Youngsoon; Moon, Eui-seong; Lee, Du Hyeong; Kang, Hani; Kang, Heon

    2013-08-01

    We present a capacitor-type device that can generate strong electrostatic field in condensed phase. The device comprises an ice film grown on a cold metal substrate in vacuum, and the film is charged by trapping Cs+ ions on the ice surface with thermodynamic surface energy. Electric field within the charged film was monitored through measuring the film voltage using a Kelvin work function probe and the vibrational Stark effect of acetonitrile using IR spectroscopy. These measurements show that the electric field can be increased to ˜4 × 108 V m-1, higher than that achievable by conventional metal plate capacitors. In addition, the present device may provide several advantages in studying the effects of electric field on molecules in condensed phase, such as the ability to control the sample composition and structure at molecular scale and the spectroscopic monitoring of the sample under electric field.

  7. Overnight Custody Arrangements, Attachment, and Adjustment Among Very Young Children

    PubMed Central

    Tornello, Samantha L.; Emery, Robert; Rowen, Jenna; Potter, Daniel; Ocker, Bailey; Xu, Yishan

    2014-01-01

    Large numbers of infants and toddlers have parents who live apart due to separation, divorce, or nonmarital/noncohabiting child-bearing, yet this important topic, especially the controversial issue of frequent overnights with nonresidential parents, is understudied. The authors analyzed data from the Fragile Families and Child Wellbeing Study, a longitudinal investigation of children born to primarily low-income, racial/ethnic minority parents that is representative of 20 U.S. cities with populations over 200,000. Among young children whose parents lived apart, 6.9% of infants (birth to age 1) and 5.3% of toddlers (ages 1 to 3) spent an average of at least 1 overnight per week with their nonresident parent. An additional 6.8% of toddlers spent 35% – 70% of overnights with nonresident parents. Frequent overnights were significantly associated with attachment insecurity among infants, but the relationship was less clear for toddlers. Attachment insecurity predicted adjustment problems at ages 3 and 5, but frequent overnights were not directly linked with adjustment problems at older ages. PMID:25635146

  8. Renewable Electricity Futures Study. Volume 2: Renewable Electricity Generation and Storage Technologies

    SciTech Connect

    Augustine, C.; Bain, R.; Chapman, J.; Denholm, P.; Drury, E.; Hall, D.G.; Lantz, E.; Margolis, R.; Thresher, R.; Sandor, D.; Bishop, N.A.; Brown, S.R.; Cada, G.F.; Felker, F.

    2012-06-01

    The Renewable Electricity Futures (RE Futures) Study investigated the challenges and impacts of achieving very high renewable electricity generation levels in the contiguous United States by 2050. The analysis focused on the sufficiency of the geographically diverse U.S. renewable resources to meet electricity demand over future decades, the hourly operational characteristics of the U.S. grid with high levels of variable wind and solar generation, and the potential implications of deploying high levels of renewables in the future. RE Futures focused on technical aspects of high penetration of renewable electricity; it did not focus on how to achieve such a future through policy or other measures. Given the inherent uncertainties involved with analyzing alternative long-term energy futures as well as the multiple pathways that might be taken to achieve higher levels of renewable electricity supply, RE Futures explored a range of scenarios to investigate and compare the impacts of renewable electricity penetration levels (30%-90%), future technology performance improvements, potential constraints to renewable electricity development, and future electricity demand growth assumptions. RE Futures was led by the National Renewable Energy Laboratory (NREL) and the Massachusetts Institute of Technology (MIT).

  9. Renewable Electricity Futures Study. Volume 2. Renewable Electricity Generation and Storage Technologies

    SciTech Connect

    Augustine, Chad; Bain, Richard; Chapman, Jamie; Denholm, Paul; Drury, Easan; Hall, Douglas G.; Lantz, Eric; Margolis, Robert; Thresher, Robert; Sandor, Debra; Bishop, Norman A.; Brown, Stephen R.; Felker, Fort; Fernandez, Steven J.; Goodrich, Alan C.; Hagerman, George; Heath, Garvin; O'Neil, Sean; Paquette, Joshua; Tegen, Suzanne; Young, Katherine

    2012-06-15

    The Renewable Electricity Futures (RE Futures) Study investigated the challenges and impacts of achieving very high renewable electricity generation levels in the contiguous United States by 2050. The analysis focused on the sufficiency of the geographically diverse U.S. renewable resources to meet electricity demand over future decades, the hourly operational characteristics of the U.S. grid with high levels of variable wind and solar generation, and the potential implications of deploying high levels of renewables in the future. RE Futures focused on technical aspects of high penetration of renewable electricity; it did not focus on how to achieve such a future through policy or other measures. Given the inherent uncertainties involved with analyzing alternative long-term energy futures as well as the multiple pathways that might be taken to achieve higher levels of renewable electricity supply, RE Futures explored a range of scenarios to investigate and compare the impacts of renewable electricity penetration levels (30%–90%), future technology performance improvements, potential constraints to renewable electricity development, and future electricity demand growth assumptions. RE Futures was led by the National Renewable Energy Laboratory (NREL) and the Massachusetts Institute of Technology (MIT). Learn more at the RE Futures website. http://www.nrel.gov/analysis/re_futures/

  10. Competitive electricity markets, prices and generator entry and exit

    NASA Astrophysics Data System (ADS)

    Ethier, Robert George

    The electric power industry in the United States is quickly being deregulated and restructured. In the past, new electric generation capacity was added by regulated utilities to meet forecasted demand levels and maintain reserve margins. With competitive wholesale generation, investment will be the responsibility of independent private investors. Electricity prices will assume the coordinating function which has until recently been the responsibility of regulatory agencies. Competitive prices will provide the entry and exit signals for generators in the future. Competitive electricity markets have a distinctive price formation process, and thus require a specialized price model. A mean-reverting price process with stochastic jumps is proposed as an appropriate long-run price process for annual electricity prices. This price process is used to develop an analytic real options model for private investment decisions. The required recursive infinite series solutions have not been widely used for real option models. Entry thresholds and asset values for competitive wholesale electricity markets, and exit decisions for plants with significant retirement costs (i.e. nuclear power plants), are examined. The proposed model results in significantly lower trigger prices for both entry and exit decisions, and higher asset values, when compared with other standard models. The model is used to show that the incentives for retiring a nuclear plant are very sensitive to the treatment of decommissioning costs (e.g. if plant owners do not face full decommissioning costs, retirement decisions may be economically premature.) An econometric model of short-run price behavior is estimated by the method of maximum likelihood using daily electricity prices from markets in the USA and Australia. The model specifies two mean reverting price processes with stochastic Markov switching between the regimes, which allows discontinuous jumps in electricity prices. Econometric tests show that a two

  11. Regional projections of nuclear and fossil electric power generation costs

    SciTech Connect

    Smolen, G.R.; Delene, J.G.; Fuller, L.C.; Bowers, H.I.

    1983-12-01

    The total busbar electric generating costs were estimated for locations in ten regions of the United States for base load nuclear and coal-fired power plants with a startup date of January 1995. A complete data set is supplied which specifies each parameter used to obtain the comparative results. When the comparison is based on reference cost parameters, nuclear- and coal-fired generation costs are found to be very close in most regions of the country. Nuclear power is favored in the South Atlantic region where coal must be transported over long distances, while coal-fired generation is favored in the Central and North Central regions where large reserves of cheaply mineable coal exist. The reference data set reflects recent electric utility construction experience. Significantly lower nuclear capital investment costs would result if regulatory reform and improved construction practices were instituted. The electric power generation costs for base load oil- and natural gas-fired plants were also estimated. These plants were found to be noncompetitive in all regions for those scenarios most likely to develop. Generation cost sensitivity to changes in various parameters was examined at a reference location. The sensitivity parameters included capital investment costs, lead times, capacity factors, costs of money, and coal and uranium prices. In addition to the levelized lifetime costs, year-by-year cash flows and revenue requirements are presented. The report concludes with an analysis of the economic merits of recycling spent fuel in light-water reactors.

  12. Potential for electricity generation from biomass residues in Cuba

    SciTech Connect

    Lora, E.S.

    1995-11-01

    The purpose of this paper is the study of the availability of major biomass residues in Cuba and the analysis of the electricity generation potential by using different technologies. An analysis of the changes in the country`s energy balance from 1988 up to date is presented, as well as a table with the availability study results and the energy equivalent for the following biomass residues: sugar cane bagasse and trash, rice and coffee husk, corn an cassava stalks and firewood. A total equivalent of 4.42 10{sup 6} tons/year of fuel-oil was obtained. Possible scenarios for the electricity production increase in the sugar industry are presented too. The analysis is carried out for a high stream parameter CEST and two BIG/GT system configurations. Limitations are introduced about the minimal milling capacity of the sugar mills for each technology. The calculated {open_quotes}real{close_quotes} electricity generation potential for BIG/GT systems, based on GE LM5000 CC gas turbines, an actual cane harvest of 58.0 10{sup 6} tons/year, half the available trash utilization and an specific steam consumption of 210 kg/tc, was 18601,0 GWh/year. Finally different alternatives are presented for low-scale electricity generation based on the other available agricultural residues.

  13. Analysis method for non-schedulable generation in electric systems

    NASA Astrophysics Data System (ADS)

    Moretti, P. M.; Jones, B. W.

    1982-01-01

    Elements of a cost-benefit analysis of the modification of electrical energy utility system in order to accommodate the introduction of solar and wind electric systems output are presented. A perturbation approach is adopted for the study in order to characterize the average utility load duration, the generation duration, and the kinds of generators using statistical averages, deviations, and variances. The load duration curve and the generation capacity mix are treated as characterizing the system, and total costs and fuel usage are calculated, regarding high cost fuel as a low percentage use item and low-cost fuel, high capital investment equipment as the base load configuration. The addition of unschedulable power was found to imply that base load plants would be most affected, unless wind- or solar-derived electricity meshed well with load curves. The coupling of solar and wind energy conversion systems to storage such as with hydropower is concluded to offer the best possibility for smoothing out differences in the generation-load scenarios.

  14. Identification and definition of unbundled electric generation and transmission services

    SciTech Connect

    Kirby, B.; Hirst, E.; Vancoevering, J.

    1995-03-01

    State and federal regulators, private and public utilities, large and small customers, power brokers and marketers, and others are engaged in major debates about the future structure of the electric industry. Although the outcomes are far from certain, it seems clear that customers will have much greater choices about the electric services they purchase and from whom they buy these services. This report examines the ``ancillary`` services that are today buried within the typical vertically integrated utility. These ancillary services support and make possible the provision of the basic services of generating capacity, energy supply, and power delivery. These ancillary services include: Management of generating units; reserve generating capacity to follow variations in customer loads, to provide capacity and energy when generating units or transmission lines suddenly fall, to maintain electric-system stability, and to provide local-area security; transmission-system monitoring and control; replacement of real power and energy losses; reactive-power management and voltage regulation; transmission reserves; repair and maintenance of the transmission network; metering, billing, and communications; and assurance of appropriate levels of power quality. Our focus in this report, the first output from a larger Oak Ridge National Laboratory project, is on identification and definition of these services. Later work in this project will examine more closely the costs and pricing options for each service.

  15. MEMS CLOSED CHAMBER HEAT ENGINE AND ELECTRIC GENERATOR

    NASA Technical Reports Server (NTRS)

    Landis, Geoffrey A. (Inventor)

    2005-01-01

    A heat engine, preferably combined with an electric generator, and advantageously implemented using micro-electromechanical system (MEMS) technologies as an array of one or more individual heat engine/generators. The heat engine is based on a closed chamber containing a motive medium, preferably a gas; means for alternately enabling and disabling transfer of thermal energy from a heat source to the motive medium; and at least one movable side of the chamber that moves in response to thermally-induced expansion and contraction of the motive medium, thereby converting thermal energy to oscillating movement. The electrical generator is combined with the heat engine to utilize movement of the movable side to convert mechanical work to electrical energy, preferably using electrostatic interaction in a generator capacitor. Preferably at least one heat transfer side of the chamber is placed alternately into and out of contact with the heat source by a motion capacitor, thereby alternately enabling and disabling conductive transfer of heat to the motive medium.

  16. Small-scale electric generators for arctic applications

    NASA Astrophysics Data System (ADS)

    Lamp, Thomas R.

    1995-01-01

    Forest fires that have endangered remote US Air Force sites equipped with radioisotope thermoelectric generators (RTGs) has prompted the assessment of power generating systems as substitutes for RTGs in small scale (10-120 watt) applications. A team of scientists and engineers of the US Air Forces' Wright Laboratory conductd an assessment of electrical power technologies for use by the Air Force in remote, harsh environments. The surprisingly high logistics costs of operating fossil fuel generators resulted in the extension of the assessment to non-RTG sites. The candidate power sources must operate unattended for long periods at a high level of operational reliability. Selection of the optimum power generation technology is complicated and heavily driven by the severe operating environment and compounded by the remoteness of the location. It is these site-related characteristics, more than any other, that drive the selection of a safe and economical power source for Arctic applications. A number of proven power generation technologies were evaluated. The assessment concluded that RGTs are clearly the safest, most reliable, and most economical approach to supplying electrical power for remote, difficult to assess locations. The assessment also indicated that the logistics costs associated with combustion driven generator systems could be substantially reduced through the use of conversion technologies which have been previously developed for space power applications.

  17. Managing Wind-based Electricity Generation and Storage

    NASA Astrophysics Data System (ADS)

    Zhou, Yangfang

    Among the many issues that profoundly affect the world economy every day, energy is one of the most prominent. Countries such as the U.S. strive to reduce reliance on the import of fossil fuels, and to meet increasing electricity demand without harming the environment. Two of the most promising solutions for the energy issue are to rely on renewable energy, and to develop efficient electricity storage. Renewable energy---such as wind energy and solar energy---is free, abundant, and most importantly, does not exacerbate the global warming problem. However, most renewable energy is inherently intermittent and variable, and thus can benefit greatly from coupling with electricity storage, such as grid-level industrial batteries. Grid storage can also help match the supply and demand of an entire electricity market. In addition, electricity storage such as car batteries can help reduce dependence on oil, as it can enable the development of Plug-in Hybrid Electric Vehicles, and Battery Electric Vehicles. This thesis focuses on understanding how to manage renewable energy and electricity storage properly together, and electricity storage alone. In Chapter 2, I study how to manage renewable energy, specifically wind energy. Managing wind energy is conceptually straightforward: generate and sell as much electricity as possible when prices are positive, and do nothing otherwise. However, this leads to curtailment when wind energy exceeds the transmission capacity, and possible revenue dilution when current prices are low but are expected to increase in the future. Electricity storage is being considered as a means to alleviate these problems, and also enables buying electricity from the market for later resale. But the presence of storage complicates the management of electricity generation from wind, and the value of storage for a wind-based generator is not entirely understood. I demonstrate that for such a combined generation and storage system the optimal policy does not

  18. Evaluation and Ranking of Geothermal Resources for Electrical Generation or Electrical Offset in Idaho, Montana, Oregon and Washington. Volume II.

    SciTech Connect

    Bloomquist, R. Gordon

    1985-06-01

    This volume contains appendices on: (1) resource assessment - electrical generation computer results; (2) resource assessment summary - direct use computer results; (3) electrical generation (high temperature) resource assessment computer program listing; (4) direct utilization (low temperature) resource assessment computer program listing; (5) electrical generation computer program CENTPLANT and related documentation; (6) electrical generation computer program WELLHEAD and related documentation; (7) direct utilization computer program HEATPLAN and related documentation; (8) electrical generation ranking computer program GEORANK and related documentation; (9) direct utilization ranking computer program GEORANK and related documentation; and (10) life cycle cost analysis computer program and related documentation. (ACR)

  19. Electricity generation and environmental externalities: Case studies, September 1995

    SciTech Connect

    1995-09-28

    Electricity constitutes a critical input in sustaining the Nation`s economic growth and development and the well-being of its inhabitants. However, there are byproducts of electricity production that have an undesirable effect on the environment. Most of these are emissions introduced by the combustion of fossil fuels, which accounts for nearly 70 percent of the total electricity generated in the United States. The environmental impacts (or damages) caused by these emissions are labeled environmental ``externalities.`` Included in the generic term ``externality`` are benefits or costs resulting as an unintended byproduct of an economic activity that accrue to someone other than the parties involved in the activity. This report provides an overview of the economic foundation of externalities, the Federal and State regulatory approaches, and case studies of the impacts of the externality policies adopted by three States.

  20. Microgrids in the Evolving Electricity Generation and DeliveryInfrastructure

    SciTech Connect

    Marnay, Chris; Venkataramanan, Giri

    2006-02-01

    The legacy paradigm for electricity service in most of the electrified world today is based on the centralized generation-transmission-distribution infrastructure that evolved under a regulated environment. More recently, a quest for effective economic investments, responsive markets, and sensitivity to the availability of resources, has led to various degrees of deregulation and unbundling of services. In this context, a new paradigm is emerging wherein electricity generation is intimately embedded with the load in microgrids. Development and decay of the familiar macrogrid is discussed. Three salient features of microgrids are examined to suggest that cohabitation of micro and macro grids is desirable, and that overall energy efficiency can be increased, while power is delivered to loads at appropriate levels of quality.

  1. Displacement Current and the Generation of Parallel Electric Fields

    SciTech Connect

    Song Yan; Lysak, Robert L.

    2006-04-14

    We show for the first time the dynamical relationship between the generation of magnetic field-aligned electric field (E{sub parallel}) and the temporal changes and spatial gradients of magnetic and velocity shears, and the plasma density in Earth's magnetosphere. We predict that the signatures of reconnection and auroral particle acceleration should have a correlation with low plasma density, and a localized voltage drop (V{sub parallel}) should often be associated with a localized magnetic stress concentration. Previous interpretations of the E{sub parallel} generation are mostly based on the generalized Ohm's law, causing serious confusion in understanding the nature of reconnection and auroral acceleration.

  2. Transportable electrical power generating system fueled by organic waste

    SciTech Connect

    Sanders, C.F.; Bell, A.W.; Bray, A.P.

    1992-06-16

    This patent describes a transportable electrical power generating system which is fueled by agricultural waste. It comprises: a turbine, a compressor driven by the turbine, a generator, a recuperator, a first convective heat exchanger, a furnace, a furnace chamber, a second radiant heat exchanger within the chamber, first means for providing a first air flow into the base of the furnace chamber; and second means positioned between the base and the top, a cyclone separator, an air preheater, exhaust means for exhausting the system of fumes; and a pallet to which components of the system as affixed.

  3. Use of a thermophotovoltaic generator in a hybrid electric vehicle

    NASA Astrophysics Data System (ADS)

    Morrison, Orion; Seal, Michael; West, Edward; Connelly, William

    1999-03-01

    Viking 29 is the World's first thermophotovoltaic (TPV) powered automobile. The prototype was funded by the Department of Energy and designed and built by students and faculty at the Vehicle Research Institute (VRI) at Western Washington University. Viking 29 is a series hybrid electric vehicle that utilizes TPV generators to charge its battery pack. Acceleration, speed, and handling compare to modern high performance sports cars, while emissions are cleaner than current internal combustion engine vehicles.

  4. BUILDOUT AND UPGRADE OF CENTRAL EMERGENCY GENERATOR SYSTEM, GENERATOR 3 AND 4 ELECTRICAL INSTALLATION

    SciTech Connect

    Gary D. Seifert; G. Shawn West; Kurt S. Myers; Jim Moncur

    2006-07-01

    SECTION 01000—SUMMARY OF WORK PART 1—GENERAL 1.1 SUMMARY The work to be performed under this project consists of providing the labor, equipment, and materials to perform "Buildout and Upgrade of Central Emergency Generator System, Generator 3 and 4 Electrical Installation" for the National Aeronautics and Space Administration at the Dryden Flight Research Center (NASA/DFRC), Edwards, California 93523. All modifications to existing substations and electrical distribution systems are the responsibility of the contractor. It is the contractor’s responsibility to supply a complete and functionally operational system. The work shall be performed in accordance with these specifications and the related drawings. The work of this project is defined by the plans and specifications contained and referenced herein. This work specifically includes but is not limited to the following: Scope of Work - Installation 1. Install all electrical wiring and controls for new generators 3 and 4 to match existing electrical installation for generators 1 and 2 and in accordance with drawings. Contractor shall provide as-built details for electrical installation. 2. Install battery charger systems for new generators 3 and 4 to match existing battery charging equipment and installation for generators 1 and 2. This may require exchange of some battery charger parts already on-hand. Supply power to new battery chargers from panel and breakers as shown on drawings. Utilize existing conduits already routed to generators 3 and 4 to field route the new wiring in the most reasonable way possible. 3. Install electrical wiring for fuel/lube systems for new generators 3 and 4 to match existing installation for generators 1 and 2. Supply power to lube oil heaters and fuel system (day tanks) from panel and breakers as shown on drawings. Utilize existing conduits already routed to generators 3 and 4 to field route the new wiring in the most reasonable way possible. Add any conduits necessary to

  5. Living Education: A Teacher's Guide to Overnight Sites in Oregon.

    ERIC Educational Resources Information Center

    Case, Sharon, Ed.; And Others

    This document has been prepared to encourage teachers in Oregon to plan environmental trips with their classes. It is organized into three major sections--Awareness in a Living Environment, Teaching and Planning Resources, and Directory of Overnight Sites in Oregon. Using a series of questions as guidelines, children become aware of their…

  6. Generation capacity expansion planning in deregulated electricity markets

    NASA Astrophysics Data System (ADS)

    Sharma, Deepak

    With increasing demand of electric power in the context of deregulated electricity markets, a good strategic planning for the growth of the power system is critical for our tomorrow. There is a need to build new resources in the form of generation plants and transmission lines while considering the effects of these new resources on power system operations, market economics and the long-term dynamics of the economy. In deregulation, the exercise of generation planning has undergone a paradigm shift. The first stage of generation planning is now undertaken by the individual investors. These investors see investments in generation capacity as an increasing business opportunity because of the increasing market prices. Therefore, the main objective of such a planning exercise, carried out by individual investors, is typically that of long-term profit maximization. This thesis presents some modeling frameworks for generation capacity expansion planning applicable to independent investor firms in the context of power industry deregulation. These modeling frameworks include various technical and financing issues within the process of power system planning. The proposed modeling frameworks consider the long-term decision making process of investor firms, the discrete nature of generation capacity addition and incorporates transmission network modeling. Studies have been carried out to examine the impact of the optimal investment plans on transmission network loadings in the long-run by integrating the generation capacity expansion planning framework within a modified IEEE 30-bus transmission system network. The work assesses the importance of arriving at an optimal IRR at which the firm's profit maximization objective attains an extremum value. The mathematical model is further improved to incorporate binary variables while considering discrete unit sizes, and subsequently to include the detailed transmission network representation. The proposed models are novel in the

  7. Overnight shift work: factors contributing to diagnostic discrepancies.

    PubMed

    Hanna, Tarek N; Loehfelm, Thomas; Khosa, Faisal; Rohatgi, Saurabh; Johnson, Jamlik-Omari

    2016-02-01

    The aims of the study are to identify factors contributing to preliminary interpretive discrepancies on overnight radiology resident shifts and apply this data in the context of known literature to draw parallels to attending overnight shift work schedules. Residents in one university-based training program provided preliminary interpretations of 18,488 overnight (11 pm–8 am) studies at a level 1 trauma center between July 1, 2013 and December 31, 2014. As part of their normal workflow and feedback, attendings scored the reports as major discrepancy, minor discrepancy, agree, and agree--good job. We retrospectively obtained the preliminary interpretation scores for each study. Total relative value units (RVUs) per shift were calculated as an indicator of overnight workload. The dataset was supplemented with information on trainee level, number of consecutive nights on night float, hour, modality, and per-shift RVU. The data were analyzed with proportional logistic regression and Fisher's exact test. There were 233 major discrepancies (1.26 %). Trainee level (senior vs. junior residents; 1.08 vs. 1.38 %; p < 0.05) and modality were significantly associated with performance. Increased workload affected more junior residents' performance, with R3 residents performing significantly worse on busier nights. Hour of the night was not significantly associated with performance, but there was a trend toward best performance at 2 am, with subsequent decreased accuracy throughout the remaining shift hours. Improved performance occurred after the first six night float shifts, presumably as residents acclimated to a night schedule. As overnight shift work schedules increase in popularity for residents and attendings, focused attention to factors impacting interpretative accuracy is warranted. PMID:26475281

  8. Thermoelectric power generation for hybrid-electric vehicle auxiliary power

    NASA Astrophysics Data System (ADS)

    Headings, Leon M.; Washington, Gregory N.; Midlam-Mohler, Shawn; Heremans, Joseph P.

    2009-03-01

    The plug-in hybrid-electric vehicle (PHEV) concept allows for a moderate driving range in electric mode but uses an onboard range extender to capitalize on the high energy density of fuels using a combustion-based generator, typically using an internal combustion engine. An alternative being developed here is a combustion-based thermoelectric generator in order to develop systems technologies which capitalize on the high power density and inherent benefits of solid-state thermoelectric power generation. This thermoelectric power unit may find application in many military, industrial, and consumer applications including range extension for PHEVs. In this research, a baseline prototype was constructed using a novel multi-fuel atomizer with diesel fuel, a conventional thermoelectric heat exchange configuration, and a commercially available bismuth telluride module (maximum 225°C). This prototype successfully demonstrated the viability of diesel fuel for thermoelectric power generation, provided a baseline performance for evaluating future improvements, provided the mechanism to develop simulation and analysis tools and methods, and highlighted areas requiring development. The improvements in heat transfer efficiency using catalytic combustion were evaluated, the system was redesigned to operate at temperatures around 500 °C, and the performance of advanced high temperature thermoelectric modules was examined.

  9. Electric energy production by particle thermionic-thermoelectric power generators

    NASA Technical Reports Server (NTRS)

    Oettinger, P. E.

    1980-01-01

    Thermionic-thermoelectric power generators, composed of a thin layer of porous, low work function material separating a heated emitter electrode and a cooler collector electrode, have extremely large Seebeck coefficients of over 2 mV/K and can provide significant output power. Preliminary experiments with 20-micron thick (Ba Sr Ca)O coatings, limited by evaporative loss to temperatures below 1400 K, have yielded short circuit current densities of 500 mA/sq cm and power densities of 60 mW/ sq cm. Substantially more output is expected with cesium-coated refractory oxide particle coatings operating at higher temperatures. Practical generators will have thermal-to-electrical efficiencies of 10 to 20%. Further increases can be gained by cascading these high-temperature devices with lower temperature conventional thermoelectric generators.

  10. Assessing Vulnerability of Electricity Generation Under Potential Future Droughts

    NASA Astrophysics Data System (ADS)

    Yan, E.; Tidwell, V. C.; Wigmosta, M. S.

    2014-12-01

    In the past few decades, the western US experienced increased sever, frequent, and prolonged droughts resulting in significant water availability issues, which raised questions as to how electricity sector might be vulnerable to future droughts. To improve our understanding of potential risks of electricity generation curtailment due to drought, an impact analysis was performed with a series of modeling tools including climate downscaling, competitive water-use calculator, hydrologic model for various hydrologic processes, and power-plant specific models. This presentation will demonstrate the predicted effects of potential droughts on power generation at a local level of the USGS 8-digit watersheds and individual power plants within the context of current and future characteristics of power system and water resource system.The study identified three potential drought scenarios based on historical drought records and projected climate changes from the GFDL and the PCM global climate models, for greenhouse gas emission scenarios A1B, A2, and B1 defined by the IPCC. The potential impacts under these three drought scenarios were evaluated with a hydrologic model constructed for the Pacific Northwest River Basin and California River Basin. The hydrologic model incorporates competitive water uses, climate forcing data corresponding to each of drought scenarios, and all major reservoirs that are currently supporting water withdrawal for various sectors and hydroelectric power generation. The hydrologic responses to drought scenarios predicted for each of the USGS 8-digit watersheds and reservoirs are used as input to power-plant specific models to quantify potential risk of curtailment at each power plant. The key findings from this study will help to improve understanding of spatial distribution of vulnerable power plants and watersheds as well as the scale of potential reduction of electricity generation under various drought scenarios. Beyond impacts to the existing

  11. Skutterudite Thermoelectric Generator for Electrical Power Generation from Automotive Waste Heat

    NASA Astrophysics Data System (ADS)

    Meisner, Gregory

    2012-02-01

    Filled skutterudites are state-of-the- art thermoelectric (TE) materials for electrical power generation from waste heat. They have suitable intrinsic transport properties as measured by the thermoelectric figure of merit ZT = S^2σT/κ (S = Seebeck coefficient, σ = electrical conductivity, T = temperature, and κ = thermal conductivity) and good mechanical strength for operation at vehicle exhaust gas temperatures of >550 C. We have demonstrated TE electrical power generation on a production test vehicle equipped with a fully functional prototype TE generator (TEG). It was assembled with TE modules fabricated from filled skutterudites synthesized at GM. Our results and analysis show that improvement in total power generated can be achieved by enhanced thermal and electrical interfaces and contacts. A substantial T decrease along the exhaust gas flow results in a large variation of voltage, current, and power output for each TE module depending on its position in the module array. Total TEG output power depends directly on the position-dependent T profile via the temperature dependence of both ZT and Carnot efficiency. Total TEG power output also depends on how the modules are connected in parallel or series combinations because mismatch in output voltage and/or internal resistance among the modules degrades the performance of the entire array. Uniform T profiles and consistent TE module internal resistances improve overall TEG performance.

  12. Increased use of reject heat from electric generation

    SciTech Connect

    Leigh, R.W.; Piraino, M.

    1994-02-01

    This study aims to determine existing barriers to greater use of reject heat by electric power producers, including utilities and cogenerators. It includes analytical studies of the technical and economic issues and a survey of several electric power producers. The core analytic findings of the study are that although electric utility- based, cogenerated district heating is sometimes cost competitive with currently common furnaces and boilers, it is not clearly less expensive, and is often more expensive. Since market penetration by a new technology depends on strong perceived advantages, district heating will remain at a disadvantage unless its benefits, such as lowered emissions and decreased reliance on foreign oil, are given overt financial form through subsidies or tax incentives. The central finding from the survey was that electric utilities have arrived at the same conclusion by their own routes; we present a substantial list of their reasons for not engaging in district heating or for not pursuing it more vigorously, and many of them can be summarized as the lack of a clear cost advantage for district heat. We also note that small-scale district heating systems, based on diesel generators and located near the thermal load center, show very clear cost advantages over individual furnaces. This cost advantage is consistent with the explosive growth currently observed in private cogeneration systems.

  13. (Hydroelectric project in Costa Rican rural electric generation and transmission)

    SciTech Connect

    Waddle, D.B.

    1989-11-28

    On November 6, 1989, I left for San Jose, Costa Rica. My visit was set to accomplish two activities. The first activity was a follow-on mission to gather additional information on a newly identified small hydroelectric project, in support of a rural electric generation and transmission cooperative performed for the Renewable Energy Applications and Training project. Data on stream flows, soils, geologic, and topographic information was gathered for Rio San Lorenzo, near Quesada. A reconnaissance level survey was performed for Rio Naranjillo, a river near San Marcos. The second part of the visit was dedicated to interaction with ICE, the electric utility, discussing plans to establish a comprehensive efficiency program in Costa Rica. I returned to Oak Ridge on November 16, 1989.

  14. Development and Buildup of a Stirling Radioisotope Generator Electrical Simulator

    NASA Technical Reports Server (NTRS)

    Prokop, Norman F.; Krasowski, Michael J.; Greer, Lawrence C.; Flatico, Joseph M.; Spina, Dan C.

    2008-01-01

    This paper describes the development of a Stirling Radioisotope Generator (SRG) Simulator for use in a prototype lunar robotic rover. The SRG developed at NASA Glenn Research Center (GRC) is a promising power source for the robotic exploration of the sunless areas of the moon. The simulator designed provides a power output similar to the SRG output of 5.7 A at 28 Vdc, while using ac wall power as the input power source. The designed electrical simulator provides rover developers the physical and electrical constraints of the SRG supporting parallel development of the SRG and rover. Parallel development allows the rover design team to embrace the SRG s unique constraints while development of the SRG is continued to a flight qualified version.

  15. 77 FR 65545 - Tri-State Generation and Transmission Association, Inc. v. Western Electric Coordinating Council...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-29

    ... Energy Regulatory Commission Tri-State Generation and Transmission Association, Inc. v. Western Electric Coordinating Council and North American Electric Reliability Corporation; Notice of Complaint Take notice that... petition requesting resolution of the conflict between Western Electric Coordinating Council and...

  16. Microbial Electricity Generation Enhances Decabromodiphenyl Ether (BDE-209) Degradation

    PubMed Central

    Yang, Yonggang; Xu, Meiying; He, Zhili; Guo, Jun; Sun, Guoping; Zhou, Jizhong

    2013-01-01

    Due to environmental persistence and biotoxicity of polybrominated diphenyl ethers (PBDEs), it is urgent to develop potential technologies to remediate PBDEs. Introducing electrodes for microbial electricity generation to stimulate the anaerobic degradation of organic pollutants is highly promising for bioremediation. However, it is still not clear whether the degradation of PBDEs could be promoted by this strategy. In this study, we hypothesized that the degradation of PBDEs (e.g., BDE-209) would be enhanced under microbial electricity generation condition. The functional compositions and structures of microbial communities in closed-circuit microbial fuel cell (c-MFC) and open-circuit microbial fuel cell (o-MFC) systems for BDE-209 degradation were detected by a comprehensive functional gene array, GeoChip 4.0, and linked with PBDE degradations. The results indicated that distinctly different microbial community structures were formed between c-MFCs and o-MFCs, and that lower concentrations of BDE-209 and the resulting lower brominated PBDE products were detected in c-MFCs after 70-day performance. The diversity and abundance of a variety of functional genes in c-MFCs were significantly higher than those in o-MFCs. Most genes involved in chlorinated solvent reductive dechlorination, hydroxylation, methoxylation and aromatic hydrocarbon degradation were highly enriched in c-MFCs and significantly positively correlated with the removal of PBDEs. Various other microbial functional genes for carbon, nitrogen, phosphorus and sulfur cycling, as well as energy transformation process, were also significantly increased in c-MFCs. Together, these results suggest that PBDE degradation could be enhanced by introducing the electrodes for microbial electricity generation and by specifically stimulating microbial functional genes. PMID:23940625

  17. Externalities of energy use, analyzed for shipping and electricity generation

    NASA Astrophysics Data System (ADS)

    Thomson, Heather

    Energy use is central to the modern lifestyle, but producing this energy often comes at an environmental cost. The three studies in this paper look at the tradeoffs involved in energy production. The first looks at transitioning marine vessels to natural gas from current distillate fuels. While natural gas will reduce local air pollutants, such as sulfur oxides and particulate matter, the implications for greenhouse gases depend on how the natural gas is extracted, processed, distributed, and used. Applying a "technology warming potential" (TWP) approach, natural gas as a marine fuel achieves climate parity within 30 years for diesel ignited engines, though it could take up to 190 years to reach climate parity with conventional fuels in a spark ignited engine. Movement towards natural gas as a marine fuel continues to progress, and conditions exist in some regions to make a near-term transition to natural gas feasible. The second study looks at externalities associated with electricity generation. The impact on the surrounding community is one concern when siting new electricity generating facilities. A survey was conducted of residents living near an industrial scale wind turbine and a coal-fired power plant to determine their visual and auditory effects on the residents. Results concluded that respondents living near the wind turbine were in favor of the facility. They were willing to pay an average of 2.56 a month to keep the turbine in its current location. Respondents living near the coal plant were opposed to the facility. They were willing to spend 1.82 a month to have the facility removed. The third study presents a cost effectiveness analysis of three of the main fuels used for electricity generation, namely coal, natural gas, and wind. This analysis adds social costs to the private costs traditionally utilized by investors making decisions. It utilizes previous research on visual and auditory amenity and disamenity values as well as recent published

  18. Use of a thermophotovoltaic generator in a hybrid electric vehicle

    SciTech Connect

    Morrison, O.; Seal, M.; West, E.; Connelly, W.

    1999-03-01

    Viking 29 is the World{close_quote}s first thermophotovoltaic (TPV) powered automobile. The prototype was funded by the Department of Energy and designed and built by students and faculty at the Vehicle Research Institute (VRI) at Western Washington University. Viking 29 is a series hybrid electric vehicle that utilizes TPV generators to charge its battery pack. Acceleration, speed, and handling compare to modern high performance sports cars, while emissions are cleaner than current internal combustion engine vehicles. {copyright} {ital 1999 American Institute of Physics.}

  19. Assessment of health impacts in electricity generation and use

    SciTech Connect

    Morris, S.C.

    1995-11-01

    This paper describes the health effects of concern associated with electricity generation, information from which health effects can be estimated, and how the boundaries of analysis are determined. It also describes advances, new approaches, and trends in the risk assessment process. It discusses the application of these advances to comparative risk studies. Trends in the risk assessment process include more explicit characterization of quantitative uncertainty, the broader application and acceptance of Monte Carlo analysis and other numerical methods to the propagation of uncertainties through the analysis, greater realism in risk assessment, and the application of greatly increased computational capabilities.

  20. Electrical motor/generator drive apparatus and method

    DOEpatents

    Su, Gui Jia

    2013-02-12

    The present disclosure includes electrical motor/generator drive systems and methods that significantly reduce inverter direct-current (DC) bus ripple currents and thus the volume and cost of a capacitor. The drive methodology is based on a segmented drive system that does not add switches or passive components but involves reconfiguring inverter switches and motor stator winding connections in a way that allows the formation of multiple, independent drive units and the use of simple alternated switching and optimized Pulse Width Modulation (PWM) schemes to eliminate or significantly reduce the capacitor ripple current.

  1. Submerged electricity generation plane with marine current-driven motors

    DOEpatents

    Dehlsen, James G.P.; Dehlsen, James B.; Fleming, Alexander

    2014-07-01

    An underwater apparatus for generating electric power from ocean currents and deep water tides. A submersible platform including two or more power pods, each having a rotor with fixed-pitch blades, with drivetrains housed in pressure vessels that are connected by a transverse structure providing buoyancy, which can be a wing depressor, hydrofoil, truss, or faired tube. The platform is connected to anchors on the seafloor by forward mooring lines and a vertical mooring line that restricts the depth of the device in the water column. The platform operates using passive, rather than active, depth control. The wing depressor, along with rotor drag loads, ensures the platform seeks the desired operational current velocity. The rotors are directly coupled to a hydraulic pump that drives at least one constant-speed hydraulic-motor generator set and enables hydraulic braking. A fluidic bearing decouples non-torque rotor loads to the main shaft driving the hydraulic pumps.

  2. Halbach array motor/generators: A novel generalized electric machine

    SciTech Connect

    Merritt, B.T.; Post, R.F.; Dreifuerst, G.R.; Bender, D.A.

    1995-02-01

    For many years Klaus Halbach has been investigating novel designs for permanent magnet arrays, using advanced analytical approaches and employing a keen insight into such systems. One of his motivations for this research was to find more efficient means for the utilization of permanent magnets for use in particle accelerators and in the control of particle beams. As a result of his pioneering work, high power free-electron laser systems, such as the ones built at the Lawrence Livermore Laboratory, became feasible, and his arrays have been incorporated into other particle-focusing systems of various types. This paper reports another, quite different, application of Klaus` work, in the design of high power, high efficiency, electric generators and motors. When tested, these motor/generator systems display some rather remarkable properties. Their success derives from the special properties which these arrays, which the authors choose to call {open_quotes}Halbach arrays,{close_quotes} possess.

  3. Electrical generation of stationary light in random scattering media

    NASA Astrophysics Data System (ADS)

    Redmond, S. M.; Armstrong, G. L.; Chan, H.-Y.; Mattson, E.; Mock, A.; Li, B.; Potts, J. R.; Cui, M.; Rand, S. C.; Oliveira, S. L.; Marchal, J.; Hinklin, T.; Laine, R. M.

    2004-01-01

    In recent years there has been great interest in controlling the speed of propagation of electromagnetic waves. In gases and crystals, coherent techniques have been applied to alter the speed of light without changing the physical or chemical structure of the medium. Also, light transmitted by highly disordered solids has exhibited signatures of Anderson localization, indicating the existence of a regime of ``stopped'' light that is mediated by random elastic scattering. However, to date, light has not been generated in a random medium as a pointlike excitation that is fixed in space from the outset. Here we report experimental evidence for the electrical generation and confinement of light within nanosized volumes of a random dielectric scattering medium in which a population inversion has been established, and discuss the properties of these novel light sources.

  4. On Parameterization of the Global Electric Circuit Generators

    NASA Astrophysics Data System (ADS)

    Slyunyaev, N. N.; Zhidkov, A. A.

    2016-08-01

    We consider the problem of generator parameterization in the global electric circuit (GEC) models. The relationship between the charge density and external current density distributions inside a thundercloud is studied using a one-dimensional description and a three-dimensional GEC model. It is shown that drastic conductivity variations in the vicinity of the cloud boundaries have a significant impact on the structure of the charge distribution inside the cloud. Certain restrictions on the charge density distribution in a realistic thunderstorm are found. The possibility to allow for conductivity inhomogeneities in the thunderstorm regions by introducing an effective external current density is demonstrated. Replacement of realistic thunderstorms with equivalent current dipoles in the GEC models is substantiated, an equation for the equivalent current is obtained, and the applicability range of this equation is analyzed. Relationships between the main GEC characteristics under variable parameterization of GEC generators are discussed.

  5. Evaluation of High-Performance Space Nuclear Electric Generators for Electric Propulsion Application

    NASA Technical Reports Server (NTRS)

    Woodcock, Gordon; Kross, Dennis A. (Technical Monitor)

    2002-01-01

    Electric propulsion applications are enhanced by high power-to-mass ratios for their electric power sources. At multi-megawatt levels, we can expect thrust production systems to be less than 5 kg/kWe. Application of nuclear electric propulsion to human Mars missions becomes an attractive alternative to nuclear thermal propulsion if the propulsion system is less than about 10 kg/kWe. Recent references have projected megawatt-plus nuclear electric sources at specific mass values from less than 1 kg/kWe to about 5 kg/kWe. Various assumptions are made regarding power generation cycle (turbogenerator; MHD (magnetohydrodynamics)) and reactor heat source design. The present paper compares heat source and power generation options on the basis of a parametric model that emphasizes heat transfer design and realizable hardware concept. Pressure drop (important!) is included in the power cycle analysis, and MHD and turbogenerator cycles are compared. Results indicate that power source specific mass less than 5 kg/kWe is attainable, even if peak temperatures achievable are limited to 1500 K. Projections of specific mass less than 1 kg/kWe are unrealistic, even at the highest peak temperatures considered.

  6. Review of Operational Water Consumption and Withdrawal Factors for Electricity Generating Technologies

    SciTech Connect

    Macknick, J.; Newmark, R.; Heath, G.; Hallett, K. C.

    2011-03-01

    Various studies have attempted to consolidate published estimates of water use impacts of electricity generating technologies, resulting in a wide range of technologies and values based on different primary sources of literature. The goal of this work is to consolidate the various primary literature estimates of water use during the generation of electricity by conventional and renewable electricity generating technologies in the United States to more completely convey the variability and uncertainty associated with water use in electricity generating technologies.

  7. Impacts of Potential Future Droughts on Electricity Generation

    NASA Astrophysics Data System (ADS)

    Yan, E.; Wigmosta, M. S.; Tidwell, V. C.; King, C. W.

    2013-12-01

    In 2011, the state of Texas experienced the worst single-year drought on record. This recent extreme climate event raised questions as to how future droughts might impact ERCOT operations. To improve our understanding of potential risks of electricity generation curtailment due to drought, an impact analysis was performed with a series of modeling tools including climate downscaling, competitive water-use calculator, hydrologic model for various hydrologic processes, and power-plant specific models. This presentation will demonstrate the predicted effects of potential future droughts on power generation at a local level of the USGS 8-digit watersheds and power plants within the context of long-term transmission planning. The study identified three potential drought scenarios (single- and multiple-year droughts) based on historical drought records and projected climate changes from the GFDL and the PCM global climate models, for greenhouse gas emission scenarios A1B, A2, and B1 defined by the IPCC. The potential impacts under these three drought scenarios were evaluated with a hydrologic model constructed for the Texas-Gulf river basin. The Texas-Gulf hydrologic model incorporates competitive water uses, climate forcing data corresponding to each of drought scenarios, and 125 reservoirs that are currently supporting water withdrawal for various sectors and cooling water for power generation. The hydrologic responses to drought scenarios predicted for each of the USGS 8-digit watersheds (such as evapotranspiration, soil water, water yield from watersheds, stream flow, and water storage in reservoirs) provide a bases to assess if power plants potentially at risk of being of derated and watersheds are vulnerable to droughts. The key findings from this study will help to improve understanding of spatial distribution of power plants at risk and vulnerable watersheds as well as the scale of potential reduction of electricity generation. Beyond impacts to the existing

  8. Feasibility study of wind-generated electricity for rural applications in southwestern Ohio

    NASA Astrophysics Data System (ADS)

    Kohring, G. W.

    The parameters associated with domestic production of wind generated electricity for direct use by small farms and rural homes in the southwestern Ohio region are discussed. The project involves direct utility interfaced electricity generation from a horizontal axis, down-wind, fixed pitch, wind powered induction generator system. Goals of the project are to determine: the ability to produce useful amounts of domestic wind generated electricity in the southwestern Ohio region; economic justification for domestic wind generated electrical production; and the potential of domestic wind generated electricity for reducing dependence on non-renewable energy resources in the southwestern Ohio region.

  9. Effect of sleep deprivation on overnight bronchoconstriction in nocturnal asthma.

    PubMed

    Catterall, J R; Rhind, G B; Stewart, I C; Whyte, K F; Shapiro, C M; Douglas, N J

    1986-09-01

    Nocturnal cough and wheeze are common in asthma. The cause of nocturnal asthma is unknown and there is conflicting evidence on whether sleep is a factor. Twelve adult asthmatic subjects with nocturnal wheeze were studied on two occasions: on one night subjects were allowed to sleep and on the other they were kept awake all night, wakefulness being confirmed by electroencephalogram. Every patient developed bronchoconstriction overnight both on the asleep night, when peak expiratory flow (PEF) fell from a mean (SE) of 418 (40) 1 min-1 at 10 pm to 270 (46) 1 min-1 in the morning, and on the awake night (PEF 10 pm 465 (43), morning 371 (43) 1 min-1). The morning values of PEF were, however, higher (p less than 0.1) after the awake night and both the absolute and the percentage overnight falls in PEF were greater when the patients slept (asleep night 38% (6%), awake night 20% (4%); p less than 0.01). This study suggests that sleep is an important factor in determining overnight bronchoconstriction in patients with nocturnal asthma.

  10. Stationary diesel engines for use with generators to supply electric power

    NASA Technical Reports Server (NTRS)

    1977-01-01

    The procurement of stationary diesel engines for on-site generation of electric power deals with technical criteria and policy relating to federal agency, not electrical components of diesel-generator sets or for the design of electric-power generating plants or their air-pollution or noise control equipment.

  11. Is It Better to Burn or Bury Waste for Clean Electricity Generation?

    EPA Science Inventory

    The generation of electricity through renewables has increased 5% since 2002. Although considerably less prominent than solar and wind, the use of municipal solid waste (MSW) to generate electricity represents roughly 14 percent of U.S. non-hydro renewable electricity generation....

  12. The greenhouse impact of unconventional gas for electricity generation

    NASA Astrophysics Data System (ADS)

    Hultman, Nathan; Rebois, Dylan; Scholten, Michael; Ramig, Christopher

    2011-10-01

    New techniques to extract natural gas from unconventional resources have become economically competitive over the past several years, leading to a rapid and largely unanticipated expansion in natural gas production. The US Energy Information Administration projects that unconventional gas will supply nearly half of US gas production by 2035. In addition, by significantly expanding and diversifying the gas supply internationally, the exploitation of new unconventional gas resources has the potential to reshape energy policy at national and international levels—altering geopolitics and energy security, recasting the economics of energy technology investment decisions, and shifting trends in greenhouse gas (GHG) emissions. In anticipation of this expansion, one of the perceived core advantages of unconventional gas—its relatively moderate GHG impact compared to coal—has recently come under scrutiny. In this paper, we compare the GHG footprints of conventional natural gas, unconventional natural gas (i.e. shale gas that has been produced using the process of hydraulic fracturing, or 'fracking'), and coal in a transparent and consistent way, focusing primarily on the electricity generation sector. We show that for electricity generation the GHG impacts of shale gas are 11% higher than those of conventional gas, and only 56% that of coal for standard assumptions.

  13. Coal's role in electrical power generation: Will it remain competitive?

    SciTech Connect

    Vogel, C.

    1999-07-01

    Coal is the most abundant worldwide fossil fuel. In the US, coal represents 95% of fossil energy reserves. The US coal resources represent more energy than either proven oil or natural gas reserves and can be expected to last more than 250 years at current consumption rates. Coal fired power plants currently produce 56% of electrical generation in the US and 36% worldwide, and forecasts show coal use to increase. Impressive statistics such as these, along with the direct correlation between electrical growth and GDP should indicate that coal has a bright future. There are some clouds on the horizon, however, that could dim this seemingly rosy picture. Potentially, the greatest challenge to coal's future is CO2 emission restrictions to address global climate change. Realistically, coal has to be a part of the generation mix of developing nations, particularly those with abundant coal resources such as China and India. If electrification of these countries and corresponding economic growth is to take place, there are not presently a lot of cost effective alternatives. This paper presents a discussion of what the coal industry is doing to remain competitive. It looks at environmental and competitive issues facing coal use.

  14. Assessing climate benefits of natural gas and coal electricity generation

    NASA Astrophysics Data System (ADS)

    Zhang, Xiaochun; Myhrvold, Nathan; Caldeira, Ken

    2015-04-01

    A transition from a system of coal electricity generation to near-zero emission electricity generation will be central to any effort to mitigate climate change. Natural gas is increasingly seen as a 'bridge fuel' for transitions form coal to near-zero emission energy sources. However, various studies use different metrics to estimate the climate impact of natural gas utilization, and led to differing conclusions. Thus, there is a need to identify the key factors affecting the climate effects of natural gas and coal electricity production, and to present these climate effects in as clear and transparent a way as possible. Here, we identify power plant efficiency and methane leakage rate as the key factors that explain most of the variance in greenhouse gas emissions by natural gas and coal power plants. We then develop a power plant GHG emission model, apply available life-cycle parameters to calculate associated CO2 and CH4 emissions and assess climate effects. Simple underlying physical changes can be obscured by abstract evaluation metrics, thus we base our discussion on temperature changes over time. We find that, during the period of plant operation, if there is substantial natural gas leakage, natural gas plants can produce greater near-term warming than a coal plant with the same power output. If leakage rates can be made to be low and efficiency high, natural gas plants can produce some reduction in near-term warming. However, without carbon capture and storage natural gas power plants cannot achieve the deep reductions that would be required to avoid substantial contribution to additional global warming. Achieving climate benefits from the use of natural gas depends on building high-efficiency natural gas plants, controlling methane leakage, and on developing a policy environment that assures a transition to future lower-emission technologies. For more information please see http://iopscience.iop.org/1748-9326/9/11/114022/article .

  15. Development of a new generation of small scale biomass-fueled electric generating power plants

    SciTech Connect

    Craig, J.D.; Purvis, C.R.

    1995-11-01

    There exists a need by a large worldwide market for greatly improved small scale (1 to 20 MWe per unit) biomass-fueled power plants. These power plants will significantly increase the efficiency of generating electric power from wood and bagasse as well as convert non-traditional fuel sources such as rice hulls, animal manure, cotton gin trash, straws, and grasses to electricity. Advancing the technology of biomass-fueled power plants will greatly expand the use of this environmentally friendly sustainable 24 hr-per-day source of electrical power for industry and communities worldwide. This paper briefly describes the status of a biomass-fueled power plant under development by Cratech, Inc.

  16. Low-temperature Stirling Engine for Geothermal Electricity Generation

    SciTech Connect

    Stillman, Greg; Weaver, Samuel P.

    2013-03-27

    Up to 2700 terawatt-hours per year of geothermal electricity generation capacity has been shown to be available within North America, typically with wells drilled into geologically active regions of the earth's crust where this energy is concentrated (Huttrer, 2001). Of this potential, about half is considered to have temperatures high enough for conventional (steam-based) power production, while the other half requires unconventional power conversion approaches, such as organic Rankine cycle systems or Stirling engines. If captured and converted effectively, geothermal power generation could replace up to 100GW of fossil fuel electric power generation, leading to a significant reduction of US power sector emissions. In addition, with the rapid growth of hydro-fracking in oil and gas production, there are smaller-scale distributed power generation opportunities in heated liquids that are co-produced with the main products. Since 2006, Cool Energy, Inc. (CEI) has designed, fabricated and tested four generations of low-temperature (100°C to 300°C) Stirling engine power conversion equipment. The electric power output of these engines has been demonstrated at over 2kWe and over 16% thermal conversion efficiency for an input temperature of 215°C and a rejection temperature of 15°C. Initial pilot units have been shipped to development partners for further testing and validation, and significantly larger engines (20+ kWe) have been shown to be feasible and conceptually designed. Originally intended for waste heat recovery (WHR) applications, these engines are easily adaptable to geothermal heat sources, as the heat supply temperatures are similar. Both the current and the 20+ kWe designs use novel approaches of self-lubricating, low-wear-rate bearing surfaces, non-metallic regenerators, and high-effectiveness heat exchangers. By extending CEI's current 3 kWe SolarHeart® Engine into the tens of kWe range, many additional applications are possible, as one 20 k

  17. Coupling dark metabolism to electricity generation using photosynthetic cocultures.

    PubMed

    Badalamenti, Jonathan P; Torres, César I; Krajmalnik-Brown, Rosa

    2014-02-01

    We investigated the role of green sulfur bacteria inlight-responsive electricity generation in microbial electrochemical cells (MXCs). We operated MXCs containing either monocultures or defined cocultures of previously enriched phototrophic Chlorobium and anode-respiring Geobacter under anaerobic conditions in the absence of electron donor. Monoculture control MXCs containing Geobacter or Chlorobium neither responded to light nor produced current, respectively. Instead, light-responsive current generation occurred only in coculture MXCs. Current increased above background levels only in the dark and declined slowly over 96 h. This pattern suggested that Chlorobium exhausted intracellular glycogen reserves via dark fermentation to supply an electron donor, presumably acetate, to Geobacter. With medium containing sulfide as the sole photosynthetic electron donor, current generation had a similar and reproducible negative light response. To investigate whether this metabolic interaction also occurred without an electrode, we performed coculture experiments in batch serum bottles. In this setup, sulfide served as the sole electron donor, whose oxidation by Chlorobium was required to provide S(0) as the electron acceptor to Geobacter. Copies of Geobacter 16S rDNA increased approximately 14-fold in batch bottle cocultures containing sulfide compared to those lacking sulfide, and did not decline after termination of sulfide feeding. These results suggest that products of both photosynthesis and dark fermentation by Chlorobium were sufficient both to yield an electrochemical response by Geobacter biofilms, and to promote Geobacter growthin batch cocultures. Our work expands upon the fusion of MXCs with coculture techniques and reinforces the utility of microbial electrochemistry for sensitive, real-time monitoring of microbial interactions in which a metabolic intermediate can be converted to electrical current.

  18. Unbundling generation and transmission services for competitive electricity markets

    SciTech Connect

    Hirst, E.; Kirby, B.

    1998-01-01

    Ancillary services are those functions performed by the equipment and people that generate, control, and transmit electricity in support of the basic services of generating capacity, energy supply, and power delivery. The Federal Energy Regulatory Commission (FERC) defined such services as those `necessary to support the transmission of electric power from seller to purchaser given the obligations of control areas and transmitting utilities within those control areas to maintain reliable operations of the interconnected transmission system.` The nationwide cost of ancillary services is about $12 billion a year, roughly 10% of the cost of the energy commodity. More important than the cost, however, is the necessity of these services for bulk-power reliability and for the support of commercial transactions. FERC`s landmark Order 888 included a pro forma tariff with provision for six key ancillary services. The Interconnected Operations Services Working Group identified another six services that it felt were essential to the operation of bulk-power systems. Several groups throughput the United States have created or are forming independent system operators, which will be responsible for reliability and commerce. To date, the electricity industry (including traditional vertically integrated utilities, distribution utilities, power markets and brokers, customers, and state and federal regulators) has paid insufficient attention to these services. Although the industry had made substantial progress in identifying and defining the key services, much remains to be doe to specify methods to measure the production, delivery, and consumption of these services; to identify the costs and cost-allocation factors for these services; and to develop market and operating rules for their provision and pricing. Developing metrics, determining costs, and setting pricing rules are important because most of these ancillary services are produced by the same pieces of equipment that

  19. Transmission cost minimization strategies for wind-electric generating facilities

    SciTech Connect

    Gonzalez, R.

    1997-12-31

    Integrating wind-electric generation facilities into existing power systems presents opportunities not encountered in conventional energy projects. Minimizing outlet cost requires probabilistic value-based analyses appropriately reflecting the wind facility`s operational characteristics. The wind resource`s intermittent nature permits relaxation of deterministic criteria addressing outlet configuration and capacity required relative to facility rating. Equivalent capacity ratings of wind generation facilities being a fraction of installed nameplate rating, outlet design studies contingency analyses can concentrate on this fractional value. Further, given its non-dispatchable, low capacity factor nature, a lower level of redundancy in outlet facilities is appropriate considering the trifling contribution to output unreliability. Further cost reduction opportunities arise from {open_quotes}wind speed/generator power output{close_quotes} and {open_quotes}wind speed/overhead conductor rating{close_quotes} functions` correlation. Proper analysis permits the correlation`s exploitation to safely increase line ratings. Lastly, poor correlation between output and utility load may permit use of smaller conductors, whose higher (mostly off-peak) losses are economically justifiable.

  20. Computational Needs for the Next Generation Electric Grid Proceedings

    SciTech Connect

    Birman, Kenneth; Ganesh, Lakshmi; Renessee, Robbert van; Ferris, Michael; Hofmann, Andreas; Williams, Brian; Sztipanovits, Janos; Hemingway, Graham; University, Vanderbilt; Bose, Anjan; Stivastava, Anurag; Grijalva, Santiago; Grijalva, Santiago; Ryan, Sarah M.; McCalley, James D.; Woodruff, David L.; Xiong, Jinjun; Acar, Emrah; Agrawal, Bhavna; Conn, Andrew R.; Ditlow, Gary; Feldmann, Peter; Finkler, Ulrich; Gaucher, Brian; Gupta, Anshul; Heng, Fook-Luen; Kalagnanam, Jayant R; Koc, Ali; Kung, David; Phan, Dung; Singhee, Amith; Smith, Basil

    2011-10-05

    The April 2011 DOE workshop, 'Computational Needs for the Next Generation Electric Grid', was the culmination of a year-long process to bring together some of the Nation's leading researchers and experts to identify computational challenges associated with the operation and planning of the electric power system. The attached papers provide a journey into these experts' insights, highlighting a class of mathematical and computational problems relevant for potential power systems research. While each paper defines a specific problem area, there were several recurrent themes. First, the breadth and depth of power system data has expanded tremendously over the past decade. This provides the potential for new control approaches and operator tools that can enhance system efficiencies and improve reliability. However, the large volume of data poses its own challenges, and could benefit from application of advances in computer networking and architecture, as well as data base structures. Second, the computational complexity of the underlying system problems is growing. Transmitting electricity from clean, domestic energy resources in remote regions to urban consumers, for example, requires broader, regional planning over multi-decade time horizons. Yet, it may also mean operational focus on local solutions and shorter timescales, as reactive power and system dynamics (including fast switching and controls) play an increasingly critical role in achieving stability and ultimately reliability. The expected growth in reliance on variable renewable sources of electricity generation places an exclamation point on both of these observations, and highlights the need for new focus in areas such as stochastic optimization to accommodate the increased uncertainty that is occurring in both planning and operations. Application of research advances in algorithms (especially related to optimization techniques and uncertainty quantification) could accelerate power system software tool

  1. Development of Electricity Generation from Renewable Energy Sources in Turkey

    NASA Astrophysics Data System (ADS)

    Kentel, E.

    2011-12-01

    Electricity is mainly produced from coal, natural gas and hydropower in Turkey. However, almost all the natural gas and high quality coal are imported. Thus, increasing the shares of both hydro and other renewables in energy supply is necessary to decrease dependency of the country on foreign sources. In 2008, the total installed capacity of Turkey was around 42000 MW and 66 % of this was from thermal sources. The remaining 33 % was from hydro, which leaves only one percent for the other renewable energy sources. The share of renewable energy in the energy budget of Turkey has increased in the last two decades; however, in 2008, only 17 % of the total electricity generation was realized from renewable sources most of which was hydro. According to State Hydraulic Works (SHW) which is the primary executive state agency responsible for the planning, operating and managing of Turkey's water resources, Turkey utilizes only around 35% of its economically viable hydro potential. The current situation clearly demonstrates the need for increasing the share of renewables in the energy budget. New laws, such as the Electricity Market Law, have been enacted and the following items were identified by the Ministry of Energy and Natural Resources of Turkey among primary energy policies and priorities: (i) decreasing dependency on foreign resources by prioritizing utilization of natural resources, (ii) increasing the share of renewable energy resources in the energy budget of Turkey; (iii) minimization of adverse environmental impacts of production and utilization of natural resources. The government's energy policy increased investments in renewable energy resources; however lack of a needed legal framework brought various environmental and social problems with this fast development. The development of the share of renewable resources in the energy budget, current government policy, and environmental concerns related with renewables, and ideas to improve the overall benefits of

  2. CdTe Photovoltaics for Sustainable Electricity Generation

    NASA Astrophysics Data System (ADS)

    Munshi, Amit; Sampath, Walajabad

    2016-09-01

    Thin film CdTe (cadmium telluride) is an important technology in the development of sustainable and affordable electricity generation. More than 10 GW of installations have been carried out using this technology around the globe. It has been demonstrated as a sustainable, green, renewable, affordable and abundant source of electricity. An advanced sublimation tool has been developed that allows highly controlled deposition of CdTe films onto commercial soda lime glass substrates. All deposition and treatment steps can be performed without breaking the vacuum within a single chamber in an inline process that can be conveniently scaled to a commercial process. In addition, an advanced cosublimation source has been developed to allow the deposition of ternary alloys such as Cd x Mg1- x Te to form an electron reflector layer which is expected to address the voltage deficits in current CdTe devices and to achieve very high efficiency. Extensive materials characterization, including but not limited to scanning electron microscopy, transmission electron microscopy, energy dispersive x-ray spectroscopy, high resolution transmission electron microscopy and electron back-scatter diffraction, has been performed to get a better understanding of the effects of processing conditions on CdTe thin film photovoltaics. This combined with computer modeling such as density function theory modeling gives a new insight into the mechanism of CdTe photovoltaic function. With all these efforts, CdTe photovoltaics has seen great progress in the last few years. Currently, it has been recorded as the cheapest source of electricity in the USA on a commercial scale, and further improvements are predicted to further reduce the cost while increasing its utilization. Here, we give an overview of the advantages of thin film CdTe photovoltaics as well as a brief review of the challenges that need to be addressed. Some fundamental studies of processing conditions for thin film CdTe are also presented

  3. Generation of a tunable environment for electrical oscillator systems.

    PubMed

    León-Montiel, R de J; Svozilík, J; Torres, Juan P

    2014-07-01

    Many physical, chemical, and biological systems can be modeled by means of random-frequency harmonic oscillator systems. Even though the noise-free evolution of harmonic oscillator systems can be easily implemented, the way to experimentally introduce, and control, noise effects due to a surrounding environment remains a subject of lively interest. Here, we experimentally demonstrate a setup that provides a unique tool to generate a fully tunable environment for classical electrical oscillator systems. We illustrate the operation of the setup by implementing the case of a damped random-frequency harmonic oscillator. The high degree of tunability and control of our scheme is demonstrated by gradually modifying the statistics of the oscillator's frequency fluctuations. This tunable system can readily be used to experimentally study interesting noise effects, such as noise-induced transitions in systems driven by multiplicative noise, and noise-induced transport, a phenomenon that takes place in quantum and classical coupled oscillator networks.

  4. Cost and Performance Assumptions for Modeling Electricity Generation Technologies

    SciTech Connect

    Tidball, Rick; Bluestein, Joel; Rodriguez, Nick; Knoke, Stu

    2010-11-01

    The goal of this project was to compare and contrast utility scale power plant characteristics used in data sets that support energy market models. Characteristics include both technology cost and technology performance projections to the year 2050. Cost parameters include installed capital costs and operation and maintenance (O&M) costs. Performance parameters include plant size, heat rate, capacity factor or availability factor, and plant lifetime. Conventional, renewable, and emerging electricity generating technologies were considered. Six data sets, each associated with a different model, were selected. Two of the data sets represent modeled results, not direct model inputs. These two data sets include cost and performance improvements that result from increased deployment as well as resulting capacity factors estimated from particular model runs; other data sets represent model input data. For the technologies contained in each data set, the levelized cost of energy (LCOE) was also evaluated, according to published cost, performance, and fuel assumptions.

  5. Electric field induced second harmonic generation with and without fringes

    NASA Astrophysics Data System (ADS)

    Meshulam, G.; Berkovic, G.; Kotler, Z.; Sa'ar, A.

    2000-09-01

    Electric field induced second harmonic generation (EFISH) is a well-known technique to measure the first hyperpolarizability (β) of organic molecules in solution. The characteristic experimental output is observation of oscillatory fringes of second harmonic radiation as the solution path length is changed and evaluation of β from the fringe amplitude. We present two different cases where even in the absence of these characteristic fringes β may still be evaluated: first, when using absorbing materials, and second, when using broadband laser sources. The ability to determine β by EFISH under these conditions greatly enhances the ability of this technique to measure β values over a wide range of laser frequencies. Measurements of the same molecule's β values at different frequencies are reported, verifying the two-level model for the dispersion of β.

  6. Fast Reactor Subassembly Design Modifications for Increasing Electricity Generation Efficiency

    SciTech Connect

    R. Wigeland; K. Hamman

    2009-09-01

    Suggested for Track 7: Advances in Reactor Core Design and In-Core Management _____________________________________________________________________________________ Fast Reactor Subassembly Design Modifications for Increasing Electricity Generation Efficiency R. Wigeland and K. Hamman Idaho National Laboratory Given the ability of fast reactors to effectively transmute the transuranic elements as are present in spent nuclear fuel, fast reactors are being considered as one element of future nuclear power systems to enable continued use and growth of nuclear power by limiting high-level waste generation. However, a key issue for fast reactors is higher electricity cost relative to other forms of nuclear energy generation. The economics of the fast reactor are affected by the amount of electric power that can be produced from a reactor, i.e., the thermal efficiency for electricity generation. The present study is examining the potential for fast reactor subassembly design changes to improve the thermal efficiency by increasing the average coolant outlet temperature without increasing peak temperatures within the subassembly, i.e., to make better use of current technology. Sodium-cooled fast reactors operate at temperatures far below the coolant boiling point, so that the maximum coolant outlet temperature is limited by the acceptable peak temperatures for the reactor fuel and cladding. Fast reactor fuel subassemblies have historically been constructed using a large number of small diameter fuel pins contained within a tube of hexagonal cross-section, or hexcan. Due to this design, there is a larger coolant flow area next to the hexcan wall as compared to flow area in the interior of the subassembly. This results in a higher flow rate near the hexcan wall, overcooling the fuel pins next to the wall, and a non-uniform coolant temperature distribution. It has been recognized for many years that this difference in sodium coolant temperature was detrimental to achieving

  7. Electricity generation from rapeseed straw hydrolysates using microbial fuel cells.

    PubMed

    Jablonska, Milena A; Rybarczyk, Maria K; Lieder, Marek

    2016-05-01

    Rapeseed straw is an attractive fuel material for microbial fuel cells (MFCs) due to its high content of carbohydrates (more than 60% carbohydrates). This study has demonstrated that reducing sugars can be efficiently extracted from raw rapeseed straw by combination of hydrothermal pretreatment and enzymatic hydrolysis followed by utilization as a fuel in two-chamber MFCs for electrical power generation. The most efficient method of saccharification of this lignocellulosic biomass (17%) turned out hydrothermal pretreatment followed by enzymatic hydrolysis. Electricity was produced using hydrolysate concentrations up to 150 mg/dm(3). The power density reached 54 mW/m(2), while CEs ranged from 60% to 10%, corresponding to the initial reducing sugar concentrations of 10-150 mg/dm(3). The COD degradation rates based on charge calculation increased from 0.445 g COD/m(2)/d for the hydrolysate obtained with the microwave treatment to 0.602 g COD/m(2)/d for the most efficient combination of hydrothermal treatment followed by enzymatic hydrolysis.

  8. Electricity generation from tetrathionate in microbial fuel cells by acidophiles.

    PubMed

    Sulonen, Mira L K; Kokko, Marika E; Lakaniemi, Aino-Maija; Puhakka, Jaakko A

    2015-03-01

    Inorganic sulfur compounds, such as tetrathionate, are often present in mining process and waste waters. The biodegradation of tetrathionate was studied under acidic conditions in aerobic batch cultivations and in anaerobic anodes of two-chamber flow-through microbial fuel cells (MFCs). All four cultures originating from biohydrometallurgical process waters from multimetal ore heap bioleaching oxidized tetrathionate aerobically at pH below 3 with sulfate as the main soluble metabolite. In addition, all cultures generated electricity from tetrathionate in MFCs at pH below 2.5 with ferric iron as the terminal cathodic electron acceptor. The maximum current and power densities during MFC operation and in the performance analysis were 79.6 mA m(-2) and 13.9 mW m(-2) and 433 mA m(-2) and 17.6 mW m(-2), respectively. However, the low coulombic efficiency (below 5%) indicates that most of the electrons were directed to other processes, such as aerobic oxidation of tetrathionate and unmeasured intermediates. The microbial community analysis revealed that the dominant species both in the anolyte and on the anode electrode surface of the MFCs were Acidithiobacillus spp. and Ferroplasma spp. This study provides a proof of concept that tetrathionate serves as electron donor for biological electricity production in the pH range of 1.2-2.5.

  9. Generation expansion planning in a competitive electric power industry

    NASA Astrophysics Data System (ADS)

    Chuang, Angela Shu-Woan

    This work investigates the application of non-cooperative game theory to generation expansion planning (GEP) in a competitive electricity industry. We identify fundamental ways competition changes the nature of GEP, review different models of oligopoly behavior, and argue that assumptions of the Cournot model are compatible with GEP. Applying Cournot theory of oligopoly behavior, we formulate a GEP model that may characterize expansion in the new competitive regime, particularly in pool-dominated generation supply industries. Our formulation incorporates multiple markets and is patterned after the basic design of the California ISO/PX system. Applying the model, we conduct numerical experiments on a test system, and analyze generation investment and market participation decisions of different candidate expansion units that vary in costs and forced outage rates. Simulations are performed under different scenarios of competition. In particular, we observe higher probabilistic measures of reliability from Cournot expansion compared to the expansion plan of a monopoly with an equivalent minimum reserve margin requirement. We prove several results for a subclass of problems encompassed by our formulation. In particular, we prove that under certain conditions Cournot competition leads to greater total capacity expansion than a situation in which generators collude in a cartel. We also show that industry output after introduction of new technology is no less than monopoly output. So a monopoly may lack sufficient incentive to introduce new technologies. Finally, we discuss the association between capacity payments and the issue of pricing reliability. And we derive a formula for computing ideal capacity payment rates by extending the Value of Service Reliability technique.

  10. Electrical Generation for More-Electric Aircraft Using Solid Oxide Fuel Cells

    SciTech Connect

    Whyatt, Greg A.; Chick, Lawrence A.

    2012-04-01

    This report examines the potential for Solid-Oxide Fuel Cells (SOFC) to provide electrical generation on-board commercial aircraft. Unlike a turbine-based auxiliary power unit (APU) a solid oxide fuel cell power unit (SOFCPU) would be more efficient than using the main engine generators to generate electricity and would operate continuously during flight. The focus of this study is on more-electric aircraft which minimize bleed air extraction from the engines and instead use electrical power obtained from generators driven by the main engines to satisfy all major loads. The increased electrical generation increases the potential fuel savings obtainable through more efficient electrical generation using a SOFCPU. However, the weight added to the aircraft by the SOFCPU impacts the main engine fuel consumption which reduces the potential fuel savings. To investigate these relationships the Boeing 787­8 was used as a case study. The potential performance of the SOFCPU was determined by coupling flowsheet modeling using ChemCAD software with a stack performance algorithm. For a given stack operating condition (cell voltage, anode utilization, stack pressure, target cell exit temperature), ChemCAD software was used to determine the cathode air rate to provide stack thermal balance, the heat exchanger duties, the gross power output for a given fuel rate, the parasitic power for the anode recycle blower and net power obtained from (or required by) the compressor/expander. The SOFC is based on the Gen4 Delphi planar SOFC with assumed modifications to tailor it to this application. The size of the stack needed to satisfy the specified condition was assessed using an empirically-based algorithm. The algorithm predicts stack power density based on the pressure, inlet temperature, cell voltage and anode and cathode inlet flows and compositions. The algorithm was developed by enhancing a model for a well-established material set operating at atmospheric pressure to reflect the

  11. Essays on the efficiency of electricity generation in Nebraska

    NASA Astrophysics Data System (ADS)

    Alvarez, Diego R.

    Fossil fuel power plants are responsible for roughly 40 percent of US CO2 emissions. While an important component of the U.S. strategy to reduce CO2 emissions in the long run involves a shift away from coal-fired generation, an effective strategy for the short and medium run entails the production of energy in the most environmentally efficient possible way. Chapter 1 evaluates the environmental efficiency of 14 Nebraska fossil-fuel electricity plants and determines whether they can reduce their CO2 emissions without decreasing their power output. Results show that the least environmentally efficient plants are natural gas-fired, peaking units and that the source of the measured inefficiency is increasing (as opposed to decreasing) returns to scale. Results also show by how much these plants can reduce their CO2 emissions without decreasing their power output, and in what way. Chapter 2 measures the environmental and the cost efficiency of the 8 largest Nebraska fossil fueled electricity plants and identifies the shadow cost of CO2 emissions abatement for these plants. The largest, base-load, coal-fired plants are the most cost efficient ones. Natural gas-fired, peaking units, have substantially lower cost efficiency scores. Some of the most environmentally efficient plants are natural gas-fired plants, as expected. However, some coal fire plants are found to be environmentally efficient as well. The average shadow price of each ton of CO2 emissions is $108. Results also show how inefficient plants can increase their cost and environmental efficiencies. Chapter 3 introduces a centralized cost and emissions minimization DEA model and applies it to the study of electricity generation by the Nebraska Public Power District (NPPD) and the Omaha Public Power District (NPPD), the two largest utilities in the state. It illustrates how the separate projection on the efficient frontier performed by traditional DEA models does not guarantee an overall minimization of cost or

  12. PBFA Z: A 50 TW/5 MJ Electrical Generator

    NASA Astrophysics Data System (ADS)

    Spielman, R. B.

    1997-05-01

    PBFA Z is a new 50 TW/5 MJ short electrical driver located at Sandia National Laboratories. We use PBFA Z to magnetically-implode solid or plasma shells. These configurations are historically known as z pinches. The pulsed power design of PBFA Z(R. B. Spielman, et al., Proc. of the Ninth IEEE Pulsed Power Conf., Albuquerque, NM 1995) is based on conventional single-pulse Marx generator, water-line pulse-forming technology used on the earlier Saturn (D. D. Bloomquist, et al., Proc. of the Sixth IEEE Pulsed Power Conf., Arlington, VA edited by P. J. Turchi and B. H. Bernstein (IEEE, New York, 1987), p. 310) and PBFA II(B. N. Turman, et al., Proc. of the Fifth IEEE Pulsed Power Conf., Arlington, VA 1985, pp. 155) accelerators. PBFA Z stores 11.4 MJ in its 36 Marx generators, couples 5 MJ in a 50 TW/100 ns pulse to the output water transmission lines, and delivers 3.4 MJ and 40 TW of electrical energy to the z-pinch load. Depending on the initial load inductance and the implosion time, we attain a peak current of 16-20 MA with a rise time of 105 ns. Current is fed to the z-pinch load through self magnetically-insulated transmission lines (MITLs). Peak electric fields in the MITLs exceed 2 MV /cm. The current from the four independent conical disk MITLs is combined together in a double post-hole vacuum convolute with an efficiency greater than 95%. The measured system performance of the water transmission lines, the vacuum insulator stack, the MITLs, and the double post-hole vacuum convolute differed from preshot predictions by ~ 5%. Using a 2-cm radius and a 2-cm length tungsten wire array with 240, 7.5-=B5m diameter wires (4.1-mg mass) as the z-pinch load, we achieved x-ray powers of 160 TW and x-ray energies of 1.85 MJ as measured by x-ray diodes and resistive bolometry.

  13. Overnight Sleep Enhances Hippocampus-Dependent Aspects of Spatial Memory

    PubMed Central

    Nguyen, Nam D.; Tucker, Matthew A.; Stickgold, Robert; Wamsley, Erin J.

    2013-01-01

    Study Objectives: Several studies have now demonstrated that spatial information is processed during sleep, and that posttraining sleep is beneficial for human navigation. However, it remains unclear whether the effects of sleep are primarily due to consolidation of cognitive maps, or alternatively, whether sleep might also affect nonhippocampal aspects of navigation (e.g., speed of motion) involved in moving through a virtual environment. Design: Participants were trained on a virtual maze navigation task (VMT) and then given a memory test following either a day of wakefulness or a night of sleep. Subjects reported to the laboratory for training at either 10:00am or 10:00pm, depending on randomly assigned condition, and were tested 11 h later. Overnight subjects slept in the laboratory with polysomnography. Setting: A hospital-based academic sleep laboratory. Patients or Participants: Thirty healthy college student volunteers. Interventions: N/A. Measurements and Results: Point-by-point position data were collected from the VMT. Analysis of the movement data revealed a sleep-dependent improvement in maze completion time (P < 0.001) due to improved spatial understanding of the maze layout, which led to a shortening of path from start to finish (P = 0.01) rather than faster exploration speed through the maze (P = 0.7). Conclusions: We found that overnight sleep benefitted performance, not because subjects moved faster through the maze, but because they were more accurate in navigating to the goal. These findings suggest that sleep enhances participants' knowledge of the spatial layout of the maze, contributing to the consolidation of hippocampus-dependent spatial information. Citation: Nguyen ND; Tucker MA; Stickgold R; Wamsley EJ. Overnight sleep enhances hippocampus-dependent aspects of spatial memory. SLEEP 2013;36(7):1051-1057. PMID:23814342

  14. Electricity generation: options for reduction in carbon emissions.

    PubMed

    Whittington, H W

    2002-08-15

    largest developed source of renewable electricity, but future large-scale projects will probably be limited to the less-developed world: the best schemes in the developed countries have already been exploited. Wave and tidal can be looked on as medium- to long-term generators of electricity, as their respective industries are not as mature as competing renewable resources. Municipal solid-waste combustion and landfill gas technologies can also be seen as short term, as can their rural equivalents, agriculture and forestry waste. Any widespread exploitation of renewable energy will depend on being able to transmit the energy from source to point of use, so the implications for the electrical network from the penetration of substantial levels of renewable energy are presented. Effective management of renewable energy installations will require technical assessment of the range of exploitation strategies, to compare local production of, say, hydrogen and the more traditional transmission of electricity. Such resources will have to compete with others in any national, or grid, system and detailed economic analysis will be necessary to determine the deployment that best fits the trading regime under which the energy will be sold. Consideration will also be necessary to determine how best to control the introduction of this radically new resource such that it does not attract punitive cost overheads until it is mature enough to cope. Finally, it is inescapable that nuclear power is a proven technology that could take its place in any future generation portfolio. Unfortunately, suspicion and mistrust surround waste management and radioactivity release. Unless this is overcome, the lack of confidence engendered by this public mistrust may result in few, if any, new nuclear power stations being built. In the event of that decision, it is difficult to see how CO(2) levels can be significantly reduced: the irony is that nuclear energy may emerge as environmentally essential. PMID

  15. Electricity generation: options for reduction in carbon emissions.

    PubMed

    Whittington, H W

    2002-08-15

    largest developed source of renewable electricity, but future large-scale projects will probably be limited to the less-developed world: the best schemes in the developed countries have already been exploited. Wave and tidal can be looked on as medium- to long-term generators of electricity, as their respective industries are not as mature as competing renewable resources. Municipal solid-waste combustion and landfill gas technologies can also be seen as short term, as can their rural equivalents, agriculture and forestry waste. Any widespread exploitation of renewable energy will depend on being able to transmit the energy from source to point of use, so the implications for the electrical network from the penetration of substantial levels of renewable energy are presented. Effective management of renewable energy installations will require technical assessment of the range of exploitation strategies, to compare local production of, say, hydrogen and the more traditional transmission of electricity. Such resources will have to compete with others in any national, or grid, system and detailed economic analysis will be necessary to determine the deployment that best fits the trading regime under which the energy will be sold. Consideration will also be necessary to determine how best to control the introduction of this radically new resource such that it does not attract punitive cost overheads until it is mature enough to cope. Finally, it is inescapable that nuclear power is a proven technology that could take its place in any future generation portfolio. Unfortunately, suspicion and mistrust surround waste management and radioactivity release. Unless this is overcome, the lack of confidence engendered by this public mistrust may result in few, if any, new nuclear power stations being built. In the event of that decision, it is difficult to see how CO(2) levels can be significantly reduced: the irony is that nuclear energy may emerge as environmentally essential.

  16. Generator voltage stabilisation for series-hybrid electric vehicles.

    PubMed

    Stewart, P; Gladwin, D; Stewart, J; Cowley, R

    2008-04-01

    This paper presents a controller for use in speed control of an internal combustion engine for series-hybrid electric vehicle applications. Particular reference is made to the stability of the rectified DC link voltage under load disturbance. In the system under consideration, the primary power source is a four-cylinder normally aspirated gasoline internal combustion engine, which is mechanically coupled to a three-phase permanent magnet AC generator. The generated AC voltage is subsequently rectified to supply a lead-acid battery, and permanent magnet traction motors via three-phase full bridge power electronic inverters. Two complementary performance objectives exist. Firstly to maintain the internal combustion engine at its optimal operating point, and secondly to supply a stable 42 V supply to the traction drive inverters. Achievement of these goals minimises the transient energy storage requirements at the DC link, with a consequent reduction in both weight and cost. These objectives imply constant velocity operation of the internal combustion engine under external load disturbances and changes in both operating conditions and vehicle speed set-points. An electronically operated throttle allows closed loop engine velocity control. System time delays and nonlinearities render closed loop control design extremely problematic. A model-based controller is designed and shown to be effective in controlling the DC link voltage, resulting in the well-conditioned operation of the hybrid vehicle. PMID:18262528

  17. Generator voltage stabilisation for series-hybrid electric vehicles.

    PubMed

    Stewart, P; Gladwin, D; Stewart, J; Cowley, R

    2008-04-01

    This paper presents a controller for use in speed control of an internal combustion engine for series-hybrid electric vehicle applications. Particular reference is made to the stability of the rectified DC link voltage under load disturbance. In the system under consideration, the primary power source is a four-cylinder normally aspirated gasoline internal combustion engine, which is mechanically coupled to a three-phase permanent magnet AC generator. The generated AC voltage is subsequently rectified to supply a lead-acid battery, and permanent magnet traction motors via three-phase full bridge power electronic inverters. Two complementary performance objectives exist. Firstly to maintain the internal combustion engine at its optimal operating point, and secondly to supply a stable 42 V supply to the traction drive inverters. Achievement of these goals minimises the transient energy storage requirements at the DC link, with a consequent reduction in both weight and cost. These objectives imply constant velocity operation of the internal combustion engine under external load disturbances and changes in both operating conditions and vehicle speed set-points. An electronically operated throttle allows closed loop engine velocity control. System time delays and nonlinearities render closed loop control design extremely problematic. A model-based controller is designed and shown to be effective in controlling the DC link voltage, resulting in the well-conditioned operation of the hybrid vehicle.

  18. 26. Photocopy of diagram (from Bernhardt Skrotzki's Electric GenerationSteam Stations, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    26. Photocopy of diagram (from Bernhardt Skrotzki's Electric Generation--Steam Stations, New York, New York, 1956, figure I-1) THE GENERAL WAY IN WHICH ELECTRICITY IS CREATED THROUGH THE STEAM GENERATION PROCESS - Portland General Electric Company, Station "L", 1841 Southeast Water Street, Portland, Multnomah County, OR

  19. Digestion of algal biomass for electricity generation in microbial fuel cells.

    PubMed

    Nishio, Koichi; Hashimoto, Kazuhito; Watanabe, Kazuya

    2013-01-01

    Algal biomass serves as a fuel for electricity generation in microbial fuel cells. This study constructed a model consortium comprised of an alga-digesting Lactobacillus and an iron-reducing Geobacter for electricity generation from photo-grown Clamydomonas cells. Total power-conversion efficiency (from Light to electricity) was estimated to be 0.47%.

  20. 76 FR 11436 - Application to Export Electric Energy; Ontario Power Generation

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-02

    ... Application to Export Electric Energy; Ontario Power Generation AGENCY: Office of Electricity Delivery and... applied to renew its authority to transmit electric energy from the United States to Canada pursuant to... authorized OPG to transmit electric energy from the United States to Canada as a power marketer for a...

  1. A Theoretical Secure Enterprise Architecture for Multi Revenue Generating Smart Grid Sub Electric Infrastructure

    ERIC Educational Resources Information Center

    Chaudhry, Hina

    2013-01-01

    This study is a part of the smart grid initiative providing electric vehicle charging infrastructure. It is a refueling structure, an energy generating photovoltaic system and charge point electric vehicle charging station. The system will utilize advanced design and technology allowing electricity to flow from the site's normal electric service…

  2. Profiting from competition: Financial tools for electric generation companies

    NASA Astrophysics Data System (ADS)

    Richter, Charles William, Jr.

    Regulations governing the operation of electric power systems in North America and many other areas of the world are undergoing major changes designed to promote competition. This process of change is often referred to as deregulation. Participants in deregulated electricity systems may find that their profits will greatly benefit from the implementation of successful bidding strategies. While the goal of the regulators may be to create rules which balance reliable power system operation with maximization of the total benefit to society, the goal of generation companies is to maximize their profit, i.e., return to their shareholders. The majority of the research described here is conducted from the point of view of generation companies (GENCOs) wishing to maximize their expected utility function, which is generally comprised of expected profit and risk. Strategies that help a GENCO to maximize its objective function must consider the impact of (and aid in making) operating decisions that may occur within a few seconds to multiple years. The work described here assumes an environment in which energy service companies (ESCOs) buy and GENCOs sell power via double auctions in regional commodity exchanges. Power is transported on wires owned by transmission companies (TRANSCOs) and distribution companies (DISTCOs). The proposed market framework allows participants to trade electrical energy contracts via the spot, futures, options, planning, and swap markets. An important method of studying these proposed markets and the behavior of participating agents is the field of experimental/computational economics. For much of the research reported here, the market simulator developed by Kumar and Sheble and similar simulators has been adapted to allow computerized agents to trade energy. Creating computerized agents that can react as rationally or irrationally as a human trader is a difficult problem for which we have turned to the field of artificial intelligence. Some of our

  3. Linear magnetic motor/generator. [to generate electric energy using magnetic flux for spacecraft power supply

    NASA Technical Reports Server (NTRS)

    Studer, P. A. (Inventor)

    1982-01-01

    A linear magnetic motor/generator is disclosed which uses magnetic flux to provide mechanical motion or electrical energy. The linear magnetic motor/generator includes an axially movable actuator mechanism. A permament magnet mechanism defines a first magnetic flux path which passes through a first end portion of the actuator mechanism. Another permament magnet mechanism defines a second magnetic flux path which passes through a second end portion of the actuator mechanism. A drive coil defines a third magnetic flux path passing through a third central portion of the actuator mechanism. A drive coil selectively adds magnetic flux to and subtracts magnetic flux from magnetic flux flowing in the first and second magnetic flux path.

  4. [The location of wind-mill electric generating plants: hygienic aspects].

    PubMed

    Kireeva, I S; Dumanskiĭ, Iu D; Semashko, P V

    2009-01-01

    The hygienic aspects of the location of wind-mill electric generating plants become more pressing due to the intensive development of wind-power engineering. Possible risk factors from wind-mill electric generating plants that can influence the environment and the population are considered. A 400-m control area is recommended on the basis of the made calculations of an acoustic and electromagnetic pollution area, an exposure area during emergency situations, as well the field measuring data on noise from wind-mill electric generating plants with a capacity of 20 MW, by applying 100-kW wind-mill electric generating units. Further studies are proposed to improve the differentiated sizes of control areas for wind-mill electric generating plants with wind-mill electric generating units of varying capacity.

  5. [The location of wind-mill electric generating plants: hygienic aspects].

    PubMed

    Kireeva, I S; Dumanskiĭ, Iu D; Semashko, P V

    2009-01-01

    The hygienic aspects of the location of wind-mill electric generating plants become more pressing due to the intensive development of wind-power engineering. Possible risk factors from wind-mill electric generating plants that can influence the environment and the population are considered. A 400-m control area is recommended on the basis of the made calculations of an acoustic and electromagnetic pollution area, an exposure area during emergency situations, as well the field measuring data on noise from wind-mill electric generating plants with a capacity of 20 MW, by applying 100-kW wind-mill electric generating units. Further studies are proposed to improve the differentiated sizes of control areas for wind-mill electric generating plants with wind-mill electric generating units of varying capacity. PMID:20000087

  6. Evaluation of glare at the Ivanpah Solar Electric Generating System

    DOE PAGESBeta

    Ho, C. K.; Sims, C. A.; Christian, J. M.

    2015-06-05

    The Ivanpah Solar Electric Generating System (ISEGS), located on I-15 about 40 miles (60 km) south of Las Vegas, NV, consists of three power towers 459 ft (140 m) tall and over 170,000 reflective heliostats with a rated capacity of 390 MW. In addition, reports of glare from the plant have been submitted by pilots and air traffic controllers and recorded by the Aviation Safety Reporting System and the California Energy Commission since 2013. Aerial and ground-based surveys of the glare were conducted in April, 2014, to identify the cause and to quantify the irradiance and potential ocular impacts ofmore » the glare. Results showed that the intense glare viewed from the airspace above ISEGS was caused by heliostats in standby mode that were aimed to the side of the receiver. Evaluation of the glare showed that the retinal irradiance and subtended source angle of the glare from the heliostats in standby were sufficient to cause significant ocular impact (potential for after-image) up to a distance of ~6 miles (10 km), but the values were below the threshold for permanent eye damage. Glare from the receivers had a low potential for after-image at all ground-based monitoring locations outside of the site boundaries. A Letter to Airmen has been issued by the Federal Aviation Administration to notify pilots of the potential glare hazards. Additional measures to mitigate the potential impacts of glare from ISGES are also presented and discussed.« less

  7. Evaluation of glare at the Ivanpah Solar Electric Generating System

    SciTech Connect

    Ho, C. K.; Sims, C. A.; Christian, J. M.

    2015-06-05

    The Ivanpah Solar Electric Generating System (ISEGS), located on I-15 about 40 miles (60 km) south of Las Vegas, NV, consists of three power towers 459 ft (140 m) tall and over 170,000 reflective heliostats with a rated capacity of 390 MW. In addition, reports of glare from the plant have been submitted by pilots and air traffic controllers and recorded by the Aviation Safety Reporting System and the California Energy Commission since 2013. Aerial and ground-based surveys of the glare were conducted in April, 2014, to identify the cause and to quantify the irradiance and potential ocular impacts of the glare. Results showed that the intense glare viewed from the airspace above ISEGS was caused by heliostats in standby mode that were aimed to the side of the receiver. Evaluation of the glare showed that the retinal irradiance and subtended source angle of the glare from the heliostats in standby were sufficient to cause significant ocular impact (potential for after-image) up to a distance of ~6 miles (10 km), but the values were below the threshold for permanent eye damage. Glare from the receivers had a low potential for after-image at all ground-based monitoring locations outside of the site boundaries. A Letter to Airmen has been issued by the Federal Aviation Administration to notify pilots of the potential glare hazards. Additional measures to mitigate the potential impacts of glare from ISGES are also presented and discussed.

  8. Evaluation of Glare at the Ivanpah Solar Electric Generating System

    SciTech Connect

    Ho, Clifford K.; Sims, Cianan; Christian, Joshua Mark

    2014-07-01

    The Ivanpah Solar Electric Generating System (ISEGS), located on I - 15 about 40 miles (60 km) south of Las Vegas, NV, consists of three power towers 459 ft (140 m) tall and over 170,000 reflective heliostats with a rated capacity of 390 MW. Reports of glare from the plant have been submitted by pilots and air traffic controllers and recorded by the Aviation Safety Reporting System and the California Energy Commission since 2013. Aerial and ground - based surveys of the glare were conducted in April, 2014, to identify the cause and to quantify the irradiance and potential ocular impact s of the glare . Results showed that the intense glare viewed from the airspace above ISEGS was caused by he liostats in standby mode that were aimed to the side of the receiver. Evaluation of the glare showed that the retinal irradiance and subtended source angle of the glare from the heliostats in standby were sufficient to cause significant ocular impact (pot ential for after - image) up to a distance of %7E6 miles (10 km), but the values were below the threshold for permanent eye damage . Glare from the receivers had a low potential for after - image at all ground - based monitoring locations outside of the site bound aries. A Letter to Airmen has been issued by the Federal Aviation Administration to notify pilots of the potential glare hazards. Additional measures to mitigate the potential impacts of glare from ISGES are also presented and discussed. This page intentionally left blank

  9. Dynamic conversion of solar generated heat to electricity

    NASA Technical Reports Server (NTRS)

    Powell, J. C.; Fourakis, E.; Hammer, J. M.; Smith, G. A.; Grosskreutz, J. C.; Mcbride, E.

    1974-01-01

    The effort undertaken during this program led to the selection of the water-superheated steam (850 psig/900 F) crescent central receiver as the preferred concept from among 11 candidate systems across the technological spectrum of the dynamic conversion of solar generated heat to electricity. The solar power plant designs were investigated in the range of plant capacities from 100 to 1000 Mw(e). The investigations considered the impacts of plant size, collector design, feed-water temperature ratio, heat rejection equipment, ground cover, and location on solar power technical and economic feasibility. For the distributed receiver systems, the optimization studies showed that plant capacities less than 100 Mw(e) may be best. Although the size of central receiver concepts was not parametrically investigated, all indications are that the optimal plant capacity for central receiver systems will be in the range from 50 to 200 Mw(e). Solar thermal power plant site selection criteria and methodology were also established and used to evaluate potentially suitable sites. The result of this effort was to identify a site south of Inyokern, California, as typically suitable for a solar thermal power plant. The criteria used in the selection process included insolation and climatological characteristics, topography, and seismic history as well as water availability.

  10. Electrical generation using a vertical-axis wind turbine

    SciTech Connect

    Clark, R.N.

    1982-12-01

    Traditionally, windmills have been of the propeller or multiblade types, both of which have their rotational axis parallel to the flow of the wind. A vertical-axis wind turbine has its rotational axis perpendicular to the flow of wind and requires no orientation to keep the rotor in the windstream. The vertical-axis wind turbine operates on the same principle as an airfoil and produces lift and drag as any airfoil. A newly designed 100-kW vertical-axis wind turbine has been operated for one year at the USDA Conservation and Production Research Laboratory, Bushland, TX. The turbine has an induction generator and supplies power to a sprinkler irrigation system with excess power being sold to the electric utility. The turbine begins producing power at 5.5 m/s windspeed and reaches its rated output of 100-kW at 15 m/s. The unit has obtained a peak efficiency of 48% at a windspeed of 8 m/s or 81% of theoretical maximum. Using 17 years of windspeed data from the National Weather Service, the annual energy output is estimated at 200,000 kWh. The unit has experienced several operational problems during its initial testing. Guy cables were enlarged to provide greater stiffness to reduce blade stress levels, lightning shorted the main contactor, and the brake system required a complete redesign and modification. The turbine was operational about 60% of the time.

  11. Solar Electric Generating System II finite element analysis

    SciTech Connect

    Dohner, J.L.; Anderson, J.R.

    1994-04-01

    On June 2, 1992, Landers` earthquake struck the Solar Electric Generating System II, located in Daggett, California. The 30 megawatt power station, operated by the Daggett Leasing Corporation (DLC), suffered substantial damage due to structural failures in the solar farm. These failures consisted of the separation of sliding joints supporting a distribution of parabolic glass mirrors. At separation, the mirrors fell to the ground and broke. It was the desire of the DLC and the Solar Thermal Design Assistance Center (STDAC) of Sandia National Laboratories (SNL) and to redesign these joints so that, in the event of future quakes, costly breakage will be avoided. To accomplish this task, drawings of collector components were developed by the STDAC, from which a detailed finite element computer model of a solar collector was produced. This nonlinear dynamic model, which consisted of over 8,560 degrees of freedom, underwent model reduction to form a low order nonlinear dynamic model containing only 40 degrees of freedom. This model was then used as a design tool to estimate joint dynamics. Using this design tool, joint configurations were modified, and an acceptable joint redesign determined. The results of this analysis showed that the implementation of metal stops welded to support shafts for the purpose of preventing joint separation is a suitable joint redesign. Moreover, it was found that, for quakes of Landers` magnitude, mirror breakage due to enhanced vibration in the trough assembly is unlikely.

  12. Air Quality Impact of Distributed Generation of Electricity

    NASA Astrophysics Data System (ADS)

    Jing, Qiguo

    This dissertation summarizes the results of a five-year investigation of the impact of distributed generation (DG) of electricity on air quality in urban areas. I focused on the impact of power plants with capacities of less than 50 MW, which is typical of DG units in urban areas. These power plants are modeled as buoyant emissions from stacks less than 10 m situated in the midst of urban buildings. Because existing dispersion models are not designed for such sources, the first step of the study involved the evaluation of AERMOD, USEPA's state-of-the art dispersion model, with data collected in a tracer study conducted in the vicinity of a DG unit. The second step of the study consisted of using AERMOD to compare the impact of DG penetration in the South Coast Air Basin of Los Angeles with the impact of replacing DG generation with expansion of current central power plant capacity. The third topic of my investigation is the development and application of a model to examine the impact of non-power plant sources in a large urban area such as Los Angeles. This model can be used to estimate the air quality impact of DG relative to other sources in an urban area. The first part of this dissertation describes a tracer study conducted in Palm Springs, CA. Concentrations observed during the nighttime experiments are generally higher than those measured during the daytime experiments. They fall off less rapidly with distance than during the daytime. AERMOD provides an adequate description of concentrations associated with the buoyant releases from the DG during the daytime when turbulence is controlled by convection induced by solar heating. However, AERMOD underestimates concentrations during the night when turbulence is generated by wind shear. Also, AERMOD predicts a decrease in concentrations with distance that is much more rapid than the relatively flat observed decrease. I have suggested modifications to AERMOD to improve the agreement between model estimates and

  13. AVESTAR Center for Operational Excellence of Electricity Generation Plants

    SciTech Connect

    Zitney, Stephen

    2012-08-29

    To address industry challenges in attaining operational excellence for electricity generation plants, the U.S. Department of Energy’s (DOE) National Energy Technology Laboratory (NETL) has launched a world-class facility for Advanced Virtual Energy Simulation Training and Research (AVESTARTM). This presentation will highlight the AVESTARTM Center simulators, facilities, and comprehensive training, education, and research programs focused on the operation and control of high-efficiency, near-zero-emission electricity generation plants. The AVESTAR Center brings together state-of-the-art, real-time, high-fidelity dynamic simulators with full-scope operator training systems (OTSs) and 3D virtual immersive training systems (ITSs) into an integrated energy plant and control room environment. AVESTAR’s initial offering combines--for the first time--a “gasification with CO2 capture” process simulator with a “combined-cycle” power simulator together in a single OTS/ITS solution for an integrated gasification combined cycle (IGCC) power plant with carbon dioxide (CO2) capture. IGCC systems are an attractive technology option for power generation, especially when capturing and storing CO2 is necessary to satisfy emission targets. The AVESTAR training program offers a variety of courses that merge classroom learning, simulator-based OTS learning in a control-room operations environment, and immersive learning in the interactive 3D virtual plant environment or ITS. All of the courses introduce trainees to base-load plant operation, control, startups, and shutdowns. Advanced courses require participants to become familiar with coordinated control, fuel switching, power-demand load shedding, and load following, as well as to problem solve equipment and process malfunctions. Designed to ensure work force development, training is offered for control room and plant field operators, as well as engineers and managers. Such comprehensive simulator-based instruction allows

  14. Short-Term Energy Outlook Model Documentation: Electricity Generation and Fuel Consumption Models

    EIA Publications

    2014-01-01

    The electricity generation and fuel consumption models of the Short-Term Energy Outlook (STEO) model provide forecasts of electricity generation from various types of energy sources and forecasts of the quantities of fossil fuels consumed for power generation. The structure of the electricity industry and the behavior of power generators varies between different areas of the United States. In order to capture these differences, the STEO electricity supply and fuel consumption models are designed to provide forecasts for the four primary Census regions.

  15. Survey of overnight academic hospitalist supervision of trainees.

    PubMed

    Farnan, Jeanne M; Burger, Alfred; Boonyasai, Romsai T; Boonayasai, Romsai T; Leykum, Luci; Harrison, Rebecca; Machulsky, Julie; Parekh, Vikas; Sharpe, Bradley A; Schleyer, Anneliese M; Arora, Vineet M

    2012-09-01

    In 2003, Accreditation Council for Graduate Medical Education (ACGME) announced the first in a series of guidelines related to the residency training. The most recent recommendations include explicit recommendations regarding the provision of on-site clinical supervision for trainees of internal medicine. To meet these standards, many internal medicine residency programs turned to hospitalist programs to fill that need. However, much is unknown about the current relationships between hospitalist and residency programs, specifically with regard to supervisory roles and supervision policies. We aimed to describe how academic hospitalists currently supervise housestaff during the on-call, or overnight, period and hospitalist program leader their perceptions of how these new policies would impact trainee-hospitalist interactions.

  16. Method of generating electricity using an endothermic coal gasifier and MHD generator

    DOEpatents

    Marchant, David D.; Lytle, John M.

    1982-01-01

    A system and method of generating electrical power wherein a mixture of carbonaceous material and water is heated to initiate and sustain the endothermic reaction of carbon and water thereby providing a gasified stream containing carbon monoxide, hydrogen and nitrogen and waste streams of hydrogen sulfide and ash. The gasified stream and an ionizing seed material and pressurized air from a preheater go to a burner for producing ionized combustion gases having a temperature of about 5000.degree. to about 6000.degree. F. which are accelerated to a velocity of about 1000 meters per second and passed through an MHD generator to generate DC power and thereafter through a diffuser to reduce the velocity. The gases from the diffuser go to an afterburner and from there in heat exchange relationship with the gasifier to provide heat to sustain the endothermic reaction of carbon and water and with the preheater to preheat the air prior to combustion with the gasified stream. Energy from the afterburner can also be used to energize other parts of the system.

  17. Nova Scotia Power shows how to generate electricity from ocean. [Annapolis Tidal Generating station

    SciTech Connect

    Not Available

    1986-02-01

    The first tidal power plant in North America has completed a successful first year of operation, reports Nova Scotia Power Corp., the utility that built it and operates it. Rated at 19 MW, it's the largest tidal generating plant in the world, but the Canadians consider it a pilot-scale installation built to test the feasibility of harnessing the unusually large tides in the Bay of Fundy on Canada's east coast. Called the Annapolis Tidal Generating station it's located on a narrow neck of land separating the Annapolis River from the Bay of Fundy. The tides there range from 15 to 25 feet, averaging 21 feet. In the average tidal cycle the plant generates electricity for about six hours, sluices water into the reservoir for about three hours, and is at a standstill for about three hours. During the first year of operation the plant produced 25 million kWh. Reported availability was 99%. It missed only eight tides out of a possible 728.

  18. Detecting failures of the glucose sensor-insulin pump system: improved overnight safety monitoring for Type-1 diabetes.

    PubMed

    Facchinetti, Andrea; Del Favero, Simone; Sparacino, Giovanni; Cobelli, Claudio

    2011-01-01

    New sensors for real-time continuous glucose monitoring (CGM) and pumps for continuous subcutaneous insulin infusion (CSII), possibly mounted on the same device, opened new scenarios for Type-1 diabetes treatment. However, possible failures of either CGM or CSII can expose diabetic patients to risks that can be dangerous especially overnight. In this contribution we present a proof-of-concept method, developed in a state-space context and implemented through a Kalman estimator, to detect in real time possible overnight failures of the sensor-pump system by simultaneously using CGM and CSII data. The method is tested on two simulated and one real subject. Results show that the method is able to correctly generate alerts for sensor-pump failures and stimulates further investigation on its development.

  19. High electric field deuterium ion sources for neutron generators

    NASA Astrophysics Data System (ADS)

    Reichenbach, Birk

    Active interrogation systems for highly enriched uranium require improved fieldable neutron sources. The target technology for deuterium-tritium neutron generators is well understood and the most significant improvement can be achieved by improving the deuterium ion source through increased output and, in some cases, lifetime of the ion source. We are developing a new approach to a deuterium ion sources based upon the field desorption/evaporation of deuterium from the surfaces of metal tips. Electrostatic field desorption (EFD) desorbs previously adsorbed deuterium as ions under the influence of high electric fields (several V/A), without removing tip material. Single etched wire tip experiments have been performed and have shown that this is difficult but can be achieved with molybdenum and tungsten tips. Electrostatic field evaporation (EFE) evaporates ultra thin deuterated titanium films as ions. It has been shown that several 10s of atomic layers can be removed within a few nanoseconds from etched tungsten tips. In the course of these studies titanium deposition and deuteration methods were studied and new detection methods developed. Space charge effects resulting from the large ion currents were identified to be the most likely cause of some unusual ion emission characteristics. In addition, on W < 110 > oriented substrates a surprising body-centered cubic crystal structure of the titanium film was found and studied. The ion currents required for neutron generator applications can be achieved by microfabrication of metal tip arrays. Field desorption studies of microfabricated field emitter tip arrays have been conducted for the first time. Maximum fields of 3 V/A have been applied to the array tip surfaces to date, although fields of ˜ 2 V/A to ˜ 2.5 V/A are more typical. Desorption of atomic deuterium ions has been observed at fields of roughly 2 V/A at room temperature. The desorption of common surface adsorbates, such as hydrogen, carbon, water, and

  20. Electrical Power Generation. A Basic Teaching Unit on Energy. Revised.

    ERIC Educational Resources Information Center

    McDermott, Hugh, Ed.; Scharmann, Larry, Ed.

    Four classroom activities are included in this 8-10 period unit suitable for high school chemistry and physics classes. The first activity is a reading (12th-grade readability level determined by the Fry procedure) which explains electricity conversion, transportation, and efficiency ratings. The second and third activities are electrical energy…

  1. Diversity of fuel sources for electricity generation in an evolving U.S. power sector

    NASA Astrophysics Data System (ADS)

    DiLuccia, Janelle G.

    Policymakers increasingly have shown interest in options to boost the relative share of renewable or clean electricity generating sources in order to reduce negative environmental externalities from fossil fuels, guard against possible resource constraints, and capture economic advantages from developing new technologies and industries. Electric utilities and non-utility generators make decisions regarding their generation mix based on a number of different factors that may or may not align with societal goals. This paper examines the makeup of the electric power sector to determine how the type of generator and the presence (or lack) of competition in electricity markets at the state level may relate to the types of fuel sources used for generation. Using state-level electricity generation data from the U.S. Energy Information Administration from 1990 through 2010, this paper employs state and time fixed-effects regression modeling to attempt to isolate the impacts of state-level restructuring policies and the emergence of non-utility generators on states' generation from coal, from fossil fuel and from renewable sources. While the analysis has significant limitations, I do find that state-level electricity restructuring has a small but significant association with lowering electricity generation from coal specifically and fossil fuels more generally. Further research into the relationship between competition and fuel sources would aid policymakers considering legislative options to influence the generation mix.

  2. Technical requirements to connect parallel generators to the Ontario Hydro Distribution Electricity System

    SciTech Connect

    Kundu, D. )

    1992-03-01

    The demand for connecting small generators to the distribution system has increased considerably since 1986. Therefore, there is a need to summarize the technical requirements for generator connection. This paper highlights the technical requirements for connecting parallel generators to the Ontario Hydro Distribution Electricity System. It also discusses some applications to connect synchronous and induction generators to the DES.

  3. Transmission Pricing Issues for Electricity Generation From Renewable Resources

    EIA Publications

    1999-01-01

    This article discusses how the resolution of transmission pricing issues which have arisen under the Federal Energy Regulatory Commission's (FERC) open access environment may affect the prospects for renewable-based electricity.

  4. Battery electrical needs for the next generation of cars

    NASA Astrophysics Data System (ADS)

    Ochiai, Takeshi

    Electric engineering has been applied to the automobile since the 19th century when the automobile was invented. It was first for the ignition system, then a variety of electrical facilities such as for the starter, headlights, wipers, etc., were developed. At present, the battery has become indispensable for the automobile. The invention of the transistor, in 1948, brought about rapid progress of microelectronics technology, involving IC, LSI, and the microcomputer. Such technologies are now widely adopted for various functions of the automobile. This paper discusses (i) the role of electronics in the automobile, especially current and future automotive electronic systems; (ii) the electric power-supply and starter; (iii) the electrical needs of the battery.

  5. Modeling strategic competition in hydro-thermal electricity generation markets with cascaded reservoir-hydroelectric generation plants

    NASA Astrophysics Data System (ADS)

    Uluca, Basak

    This dissertation aims to achieve two goals. The first is to model the strategic interactions of firms that own cascaded reservoir-hydro plants in oligopolistic and mixed oligopolistic hydrothermal electricity generation markets. Although competition in thermal generation has been extensively modeled since the beginning of deregulation, the literature on competition in hydro generation is still limited; in particular, equilibrium models of oligopoly that study the competitive behavior of firms that own reservoir-hydro plants along the same river in hydrothermal electricity generation markets are still under development. In competitive markets, when the reservoirs are located along the same river, the water released from an upstream reservoir for electricity generation becomes input to the immediate downstream reservoir, which may be owned by a competitor, for current or future use. To capture the strategic interactions among firms with cascaded reservoir-hydro plants, the Upstream-Conjecture approach is proposed. Under the Upstream-Conjecture approach, a firm with an upstream reservoir-hydro plant assumes that firms with downstream reservoir-hydro plants will respond to changes in the upstream firm's water release by adjusting their water release by the same amount. The results of the Upstream Conjecture experiments indicate that firms that own upstream reservoirs in a cascade may have incentive to withhold or limit hydro generation, forcing a reduction in the utilization of the downstream hydro generation plants that are owned by competitors. Introducing competition to hydroelectricity generation markets is challenging and ownership allocation of the previously state-owned cascaded reservoir-hydro plants through privatization can have significant impact on the competitiveness of the generation market. The second goal of the dissertation is to extract empirical guidance about best policy choices for the ownership of the state-owned generation plants, including the

  6. An electric generator using living Torpedo electric organs controlled by fluid pressure-based alternative nervous systems.

    PubMed

    Tanaka, Yo; Funano, Shun-Ichi; Nishizawa, Yohei; Kamamichi, Norihiro; Nishinaka, Masahiro; Kitamori, Takehiko

    2016-01-01

    Direct electric power generation using biological functions have become a research focus due to their low cost and cleanliness. Unlike major approaches using glucose fuels or microbial fuel cells (MFCs), we present a generation method with intrinsically high energy conversion efficiency and generation with arbitrary timing using living electric organs of Torpedo (electric rays) which are serially integrated electrocytes converting ATP into electric energy. We developed alternative nervous systems using fluid pressure to stimulate electrocytes by a neurotransmitter, acetylcholine (Ach), and demonstrated electric generation. Maximum voltage and current were 1.5 V and 0.64 mA, respectively, with a duration time of a few seconds. We also demonstrated energy accumulation in a capacitor. The current was far larger than that using general cells other than electrocytes (~pA level). The generation ability was confirmed against repetitive cycles and also after preservation for 1 day. This is the first step toward ATP-based energy harvesting devices. PMID:27241817

  7. An electric generator using living Torpedo electric organs controlled by fluid pressure-based alternative nervous systems

    PubMed Central

    Tanaka, Yo; Funano, Shun-ichi; Nishizawa, Yohei; Kamamichi, Norihiro; Nishinaka, Masahiro; Kitamori, Takehiko

    2016-01-01

    Direct electric power generation using biological functions have become a research focus due to their low cost and cleanliness. Unlike major approaches using glucose fuels or microbial fuel cells (MFCs), we present a generation method with intrinsically high energy conversion efficiency and generation with arbitrary timing using living electric organs of Torpedo (electric rays) which are serially integrated electrocytes converting ATP into electric energy. We developed alternative nervous systems using fluid pressure to stimulate electrocytes by a neurotransmitter, acetylcholine (Ach), and demonstrated electric generation. Maximum voltage and current were 1.5 V and 0.64 mA, respectively, with a duration time of a few seconds. We also demonstrated energy accumulation in a capacitor. The current was far larger than that using general cells other than electrocytes (~pA level). The generation ability was confirmed against repetitive cycles and also after preservation for 1 day. This is the first step toward ATP-based energy harvesting devices. PMID:27241817

  8. An electric generator using living Torpedo electric organs controlled by fluid pressure-based alternative nervous systems

    NASA Astrophysics Data System (ADS)

    Tanaka, Yo; Funano, Shun-Ichi; Nishizawa, Yohei; Kamamichi, Norihiro; Nishinaka, Masahiro; Kitamori, Takehiko

    2016-05-01

    Direct electric power generation using biological functions have become a research focus due to their low cost and cleanliness. Unlike major approaches using glucose fuels or microbial fuel cells (MFCs), we present a generation method with intrinsically high energy conversion efficiency and generation with arbitrary timing using living electric organs of Torpedo (electric rays) which are serially integrated electrocytes converting ATP into electric energy. We developed alternative nervous systems using fluid pressure to stimulate electrocytes by a neurotransmitter, acetylcholine (Ach), and demonstrated electric generation. Maximum voltage and current were 1.5 V and 0.64 mA, respectively, with a duration time of a few seconds. We also demonstrated energy accumulation in a capacitor. The current was far larger than that using general cells other than electrocytes (~pA level). The generation ability was confirmed against repetitive cycles and also after preservation for 1 day. This is the first step toward ATP-based energy harvesting devices.

  9. An electric generator using living Torpedo electric organs controlled by fluid pressure-based alternative nervous systems.

    PubMed

    Tanaka, Yo; Funano, Shun-Ichi; Nishizawa, Yohei; Kamamichi, Norihiro; Nishinaka, Masahiro; Kitamori, Takehiko

    2016-05-31

    Direct electric power generation using biological functions have become a research focus due to their low cost and cleanliness. Unlike major approaches using glucose fuels or microbial fuel cells (MFCs), we present a generation method with intrinsically high energy conversion efficiency and generation with arbitrary timing using living electric organs of Torpedo (electric rays) which are serially integrated electrocytes converting ATP into electric energy. We developed alternative nervous systems using fluid pressure to stimulate electrocytes by a neurotransmitter, acetylcholine (Ach), and demonstrated electric generation. Maximum voltage and current were 1.5 V and 0.64 mA, respectively, with a duration time of a few seconds. We also demonstrated energy accumulation in a capacitor. The current was far larger than that using general cells other than electrocytes (~pA level). The generation ability was confirmed against repetitive cycles and also after preservation for 1 day. This is the first step toward ATP-based energy harvesting devices.

  10. Simulation Tool to Assess Mechanical and Electrical Stresses on Wind Turbine Generators: Preprint

    SciTech Connect

    Singh, M.; Muljadi, E.; Gevorgian, V.; Jonkman, J.

    2013-10-01

    Wind turbine generators (WTGs) consist of many different components to convert kinetic energy of the wind into electrical energy for end users. Wind energy is accessed to provide mechanical torque for driving the shaft of the electrical generator. The conversion from wind power to mechanical power is governed by the aerodynamic conversion. The aerodynamic-electrical-conversion efficiency of a WTGis influenced by the efficiency of the blades, the gearbox, the generator, and the power converter. This paper describes the use of MATLAB/Simulink to simulate the electrical and grid-related aspects of a WTG coupled with the FAST aero-elastic wind turbine computer-aided engineering tool to simulate the aerodynamic and mechanical aspects of a WTG. The combination of the two enables studiesinvolving both electrical and mechanical aspects of a WTG. This digest includes some examples of the capabilities of the FAST and MATLAB coupling, namely the effects of electrical faults on the blade moments.

  11. Cooling of high power generators and motors for electric propulsion

    NASA Astrophysics Data System (ADS)

    Szatkowski, J. L.

    1984-03-01

    This study reviews the history and development of marine electric propulsion drives, the types of electric propulsion, and the inherent losses which occur within the synchronous ac machines typically used for high-power propulsion systems. A thorough review of the literature pertaining to heat transfer in electrical machinery is made. In particular, the use of liquid cooling in various flow configurations, including buoyancy-driven thermosyphons and two-phase thermosyphons is analyzed. Forced-liquid cooling is feasible, but the required rotating seals are a problem in reliability. Closed-loop thermosyphon cooling appears feasible at high rotational speeds, although a secondary heat exchange through the shaft is required. Closed, two-phase thermosyphons and heat pipes are also feasible, but require forced-air circulation for heat rejection to the ambient. Since all of these concepts deserve additional attention, areas for further research and development are recommended.

  12. Waveform generation in the weakly electric fish Gymnotus coropinae (Hoedeman): the electric organ and the electric organ discharge.

    PubMed

    Castelló, María E; Rodríguez-Cattáneo, Alejo; Aguilera, Pedro A; Iribarne, Leticia; Pereira, Ana Carolina; Caputi, Angel A

    2009-05-01

    This article deals with the electric organ and its discharge in Gymnotus coropinae, a representative species of one of the three main clades of the genus. Three regions with bilateral symmetry are described: (1) subopercular (medial and lateral columns of complex shaped electrocytes); (2) abdominal (medial and lateral columns of cuboidal and fusiform electrocytes); and (3) main [four columns, one dorso-lateral (containing fusiform electrocytes) and three medial (containing cuboidal electrocytes)]. Subopercular electrocytes are all caudally innervated whereas two of the medial subopercular ones are also rostrally innervated. Fusiform electrocytes are medially innervated at the abdominal portion, and at their rostral and caudal poles at the main portion. Cuboidal electrocytes are always caudally innervated. The subopercular portion generates a slow head-negative wave (V(1r)) followed by a head-positive spike (V(3r)). The abdominal and main portions generate a fast tetra-phasic complex (V(2345ct)). Since subopercular components prevail in the near field and the rest in the far field, time coincidence of V(3r) with V(2) leads to different waveforms depending on the position of the receiver. This confirms the splitting hypothesis of communication and exploration channels based on the different timing, frequency band and reach of the regional waveforms. The following hypothesis is compatible with the observed anatomo-functional organization: V(1r) corresponds to the rostral activation of medial subopercular electrocytes and V(3r) to the caudal activation of all subopercular electrocytes; V(2), and part of V(3ct), corresponds to the successive activation of the rostral and caudal poles of dorso-lateral fusiform electrocytes; and V(345ct) is initiated in the caudal face of cuboidal electrocytes by synaptic activation (V(3ct)) and it is completed (V(45ct)) by the successive activation of rostral and caudal faces by the action currents evoked in the opposite face. PMID

  13. Electrical characteristics of spark generators for automotive ignition

    NASA Technical Reports Server (NTRS)

    Brode, R B; Randolph, D W; Silsbee, F B

    1927-01-01

    This paper reports the results of an extensive program of measurements on 11 ignition systems differing widely in type. The results serve primarily to give representative data on the electric and magnetic constants of such systems, and on the secondary voltage produced by them under various conditions of speed, timing, shunting resistance, etc. They also serve to confirm certain of the theoretical formulas which have been proposed to connect the performance of such systems with their electrical constants, and to indicate the extent to which certain simplified model circuits duplicate the performance of the actual apparatus.

  14. Do environmental variables influence overnight weight loss of yearling steers in semiarid rangelands?

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In order to measure the weight gains of free-ranging livestock, animals are frequently corralled and confined overnight prior to weighing. Animals may take several days to recover from this overnight loss in weight associated with dehydration and excretion of urine and feces. Quantitative estimates ...

  15. Renewable resources in the US electricity supply. [Contains a report on the electricity generating technologies which use renewable resources

    SciTech Connect

    Not Available

    1993-03-05

    Renewable resources (solar, wind, geothermal, hydroelectric, biomass, and waste) currently provide nearly 12 percent of the Nation's electricity supply. Almost 10 of this 12 percent is provided by hydroelectric resources alone. Biomass and municipal solid waste (MSW) together contribute more than 1 percent. All other renewable resources, including geothermal, wind, and solar, together provide less than 1 percent of the total. Many renewable resources are relative newcomers to the electric power market. In particular, electricity generation using geothermal, wind, solar, and MSW resources have had their greatest expansion in the 1980's. This was a result of significant technological improvements, the implementation of favorable Federal and State policies, and the reaction to the increasing costs of using fossil and nuclear fuels. The use of renewable resources for electricity generation has also been encouraged as less environmentally damaging than fossil fuels. Because renewable energy is available domestically, renewable resources are viewed as more secure than imported fossil fuels. This report, Renewable Resources in the US Electricity Supply, presents descriptions of the history, current use, and forecasted future applications of renewable resources for electricity generation and of the factors that influence those applications.

  16. The 400-Hertz constant-speed electrical generation systems

    NASA Technical Reports Server (NTRS)

    Mcclung, R.

    1982-01-01

    Materials illustrating a presentation on 400 Hz constant speed generation systems are presented. The system features are outlined, components and functioning described, and display graphics illustrated.

  17. Use of Geothermal Energy for Electric Power Generation

    SciTech Connect

    Mashaw, John M.; Prichett, III, Wilson

    1980-10-23

    The National Rural Electric Cooperative Association and its 1,000 member systems are involved in the research, development and utilization of many different types of supplemental and alternative energy resources. We share a strong commitment to the wise and efficient use of this country's energy resources as the ultimate answer to our national prosperity and economic growth. WRECA is indebted to the United States Department of Energy for funding the NRECA/DOE Geothermal Workshop which was held in San Diego, California in October, 1980. We would also like to express our gratitude to each of the workshop speakers who gave of their time, talent and experience so that rural electric systems in the Western U. S. might gain a clearer understanding of the geothermal potential in their individual service areas. The participants were also presented with practical, expert opinion regarding the financial and technical considerations of using geothermal energy for electric power production. The organizers of this conference and all of those involved in planning this forum are hopeful that it will serve as an impetus toward the full utilization of geothermal energy as an important ingredient in a more energy self-sufficient nation. The ultimate consumer of the rural electric system, the member-owner, expects the kind of leadership that solves the energy problems of tomorrow by fully utilizing the resources at our disposal today.

  18. Biomechanical energy harvesting: generating electricity during walking with minimal user effort.

    PubMed

    Donelan, J M; Li, Q; Naing, V; Hoffer, J A; Weber, D J; Kuo, A D

    2008-02-01

    We have developed a biomechanical energy harvester that generates electricity during human walking with little extra effort. Unlike conventional human-powered generators that use positive muscle work, our technology assists muscles in performing negative work, analogous to regenerative braking in hybrid cars, where energy normally dissipated during braking drives a generator instead. The energy harvester mounts at the knee and selectively engages power generation at the end of the swing phase, thus assisting deceleration of the joint. Test subjects walking with one device on each leg produced an average of 5 watts of electricity, which is about 10 times that of shoe-mounted devices. The cost of harvesting-the additional metabolic power required to produce 1 watt of electricity-is less than one-eighth of that for conventional human power generation. Producing substantial electricity with little extra effort makes this method well-suited for charging powered prosthetic limbs and other portable medical devices.

  19. Biomechanical energy harvesting: generating electricity during walking with minimal user effort.

    PubMed

    Donelan, J M; Li, Q; Naing, V; Hoffer, J A; Weber, D J; Kuo, A D

    2008-02-01

    We have developed a biomechanical energy harvester that generates electricity during human walking with little extra effort. Unlike conventional human-powered generators that use positive muscle work, our technology assists muscles in performing negative work, analogous to regenerative braking in hybrid cars, where energy normally dissipated during braking drives a generator instead. The energy harvester mounts at the knee and selectively engages power generation at the end of the swing phase, thus assisting deceleration of the joint. Test subjects walking with one device on each leg produced an average of 5 watts of electricity, which is about 10 times that of shoe-mounted devices. The cost of harvesting-the additional metabolic power required to produce 1 watt of electricity-is less than one-eighth of that for conventional human power generation. Producing substantial electricity with little extra effort makes this method well-suited for charging powered prosthetic limbs and other portable medical devices. PMID:18258914

  20. Ultrawideband monocycle pulse generation based on polarization modulator and low speed electrical NRZ signal

    NASA Astrophysics Data System (ADS)

    Sun, Guodan; Zhang, Qiufang; Wang, Quan

    2015-07-01

    A novel ultrawideband (UWB) monocycle pulse generation system by modulating a polarization modulator (PolM) with a low speed electrical nonreturn-to-zero (NRZ) signal is proposed, which significantly reduce the bandwidth requirement of the driving signal. At each bit transition of the input NRZ signal, two polarity-reversed Gaussian pulses are generated. By properly setting the delay between these two Gaussian pulses, an optical UWB monocycle pulse can be generated. Biphase modulation (BPM) can be realized by electrically switching the polarization direction at the output of PolM, if an electrically tunable arbitrary wave plate (AWP) is employed.

  1. Numerical simulation of the leaky dielectric microdroplet generation in electric fields

    NASA Astrophysics Data System (ADS)

    Kamali, Reza; Manshadi, Mohammad Karim Dehghan

    2016-07-01

    Microdroplet generation has a vast range of applications in the chemical, biomedical, and biological sciences. Several devices are applied to produce microdroplets, such as Co-flow, T-junction and Flow-focusing. The important point in the producing process is controlling the separated fluid volume in these devices. On the other hand, a large number of liquids, especially aqueous one, are influenced by electric or magnetic fields. As a consequence, an electric field could be used in order to affect the separated fluid volume. In this study, effects of an electric field on the microdroplet generation in a Co-flow device are investigated numerically. Furthermore, effects of some electrical properties such as permittivity on the separating process of microdroplets are studied. Leaky dielectric and perfect dielectric models are used in this investigation. According to the results, in the microdroplet generating process, leaky dielectric fluids show different behaviors, when an electric field is applied to the device. In other words, in a constant electric field strength, the volume of generated microdroplets can increase or decrease, in comparison with the condition without the electric field. However, for perfect dielectric fluids, droplet volume always decreases with increasing the electric field strength. In order to validate the numerical method of this study, deformation of a leaky dielectric droplet in an electric field is investigated. Results are compared with Taylor theoretical model.

  2. Transient Analysis Generator /TAG/ simulates behavior of large class of electrical networks

    NASA Technical Reports Server (NTRS)

    Thomas, W. J.

    1967-01-01

    Transient Analysis Generator program simulates both transient and dc steady-state behavior of a large class of electrical networks. It generates a special analysis program for each circuit described in an easily understood and manipulated programming language. A generator or preprocessor and a simulation system make up the TAG system.

  3. Electric power generating plant having direct coupled steam and compressed air cycles

    DOEpatents

    Drost, Monte K.

    1982-01-01

    An electric power generating plant is provided with a Compressed Air Energy Storage (CAES) system which is directly coupled to the steam cycle of the generating plant. The CAES system is charged by the steam boiler during off peak hours, and drives a separate generator during peak load hours. The steam boiler load is thereby levelized throughout an operating day.

  4. Electric power generating plant having direct-coupled steam and compressed-air cycles

    DOEpatents

    Drost, M.K.

    1981-01-07

    An electric power generating plant is provided with a Compressed Air Energy Storage (CAES) system which is directly coupled to the steam cycle of the generating plant. The CAES system is charged by the steam boiler during off peak hours, and drives a separate generator during peak load hours. The steam boiler load is thereby levelized throughout an operating day.

  5. Photovoltaic electricity generation: Value for residential and commercial sectors

    NASA Astrophysics Data System (ADS)

    Bhattacharjee, Ujjwal

    The photovoltaic (PV) industry in the US has seen an upsurge in recent years, and PV holds great promise as a renewable technology with no greenhouse gas emissions with its use. We aim to assess the value of PV based electricity for users in the residential and commercial sectors focusing on the financial impacts it has, which may not be greatly recognized. Specifically, we pursue two goals. First, the emerging 'renewable portfolio standard (RPS)' adopted in several states in the country has been a driving force for large scale PV deployment, but financial incentives offered to PV in different RPS states differ considerably. We use life cycle cost model to estimate the cost of PV based electricity for thirty-two RPS states in the country. Results indicate that the levelized cost of PV electricity is high (40 to 60 Cents/kWh). When the contribution of the financial incentives (along with the cost of energy saved) is taken into account, the cost of PV based electricity is negative in some RPS states such as California, New Jersey, New York, while for most of the RPS states the cost of PV electricity continues to remain high. In addition, the states with negative or low cost of PV electricity have been driving the PV diffusion in the residential sector. Therefore, a need to adjust the financial incentive structure in different RPS states is recommended for homogenous development of the residential PV market in the country. Second, we assess the value of the PV in reducing the highest peak load demand in commercial buildings and hence the high value demand charge. The Time-of-Use (TOU) based electricity tariff is widely used by electric utilities in the commercial sector. Energy and peak load are two important facets of the TOU tariff regime. Tools are well established to estimate the energy contribution from a PV system (installed in a commercial building), but not power output on a short time interval. A joint conditional probability model has been developed that

  6. Metabolic characteristics of human subcutaneous abdominal adipose tissueafter overnight fast

    PubMed Central

    Humphreys, Sandy M.

    2012-01-01

    Subcutaneous abdominal adipose tissue is one of the largest fat depots and contributes the major proportion of circulating nonesterified fatty acids (NEFA). Little is known about aspects of human adipose tissue metabolism in vivo other than lipolysis. Here we collated data from 331 experiments in 255 healthy volunteers over a 23-year period, in which subcutaneous abdominal adipose tissue metabolism was studied by measurements of arterio-venous differences after an overnight fast. NEFA and glycerol were released in a ratio of 2.7:1, different (P < 0.001) from the value of 3.0 that would indicate no fatty acid re-esterification. Fatty acid re-esterification was 10.2 ± 1.4%. Extraction of triacylglycerol (TG) (fractional extraction 5.7 ± 0.4%) indicated intravascular lipolysis by lipoprotein lipase, and this contributed 21 ± 3% of the glycerol released. Glucose uptake (fractional extraction 2.6 ± 0.3%) was partitioned around 20–25% for provision of glycerol 3-phosphate and 30% into lactate production. There was release of lactate and pyruvate, with extraction of the ketone bodies 3-hydroxybutyrate and acetoacetate, although these were small numerically compared with TG and glucose uptake. NEFA release (expressed per 100 g tissue) correlated inversely with measures of fat mass (e.g., with BMI, rs = −0.24, P < 0.001). We examined within-person variability. Systemic NEFA concentrations, NEFA release, fatty acid re-esterification, and adipose tissue blood flow were all more consistent within than between individuals. This picture of human adipose tissue metabolism in the fasted state should contribute to a greater understanding of adipose tissue physiology and pathophysiology. PMID:22167523

  7. Toward a new generation of electrically controllable hygromorphic soft actuators.

    PubMed

    Taccola, Silvia; Greco, Francesco; Sinibaldi, Edoardo; Mondini, Alessio; Mazzolai, Barbara; Mattoli, Virgilio

    2015-03-11

    An innovative processing strategy for fabricating soft structures that possess electric- and humidity-driven active/passive actuation capabilities along with touch- and humidity-sensing properties is reported. The intrinsically multifunctional material comprises an active thin layer of poly(3,4-ethylenedioxythiophene):poly-(styrene sulfonate) in a double-layered structure with a silicone elastomer and provides an opportunity toward developing a new class of smart structures for soft robotics. PMID:25556552

  8. Generation of Electrical Power from Stimulated Muscle Contractions Evaluated

    NASA Technical Reports Server (NTRS)

    Lewandowski, Beth; Kilgore, Kevin; Ercegovic, David B.

    2004-01-01

    This project is a collaborative effort between NASA Glenn Research Center's Revolutionary Aeropropulsion Concepts (RAC) Project, part of the NASA Aerospace Propulsion and Power Program of the Aerospace Technology Enterprise, and Case Western Reserve University's Cleveland Functional Electrical Stimulation (FES) Center. The RAC Project foresees implantable power requirements for future applications such as organically based sensor platforms and robotics that can interface with the human senses. One of the goals of the FES Center is to develop a totally implantable neural prosthesis. This goal is based on feedback from patients who would prefer a system with an internal power source over the currently used system with an external power source. The conversion system under investigation would transform the energy produced from a stimulated muscle contraction into electrical energy. We hypothesize that the output power of the system will be greater than the input power necessary to initiate, sustain, and control the electrical conversion system because of the stored potential energy of the muscle. If the system can be made biocompatible, durable, and with the potential for sustained use, then the biological power source will be a viable solution.

  9. Electric Power Generation from Low to Intermediate Temperature Resources

    SciTech Connect

    Gosnold, William D.

    2015-06-18

    with ORC technology. Average co-produced water for 10,480 wells is 3.2 gallons per minute (gpm). Even excluding the tight formations, Bakken and Three Forks, average co-produced water for the remaining 3,337 is only 5 gpm. The output of the highest producing well is 184 gpm and the average of the top 100 wells is 52 gpm. Due to the depth of the oil producing formations in the Williston Basin, typically 3 km or greater, pumps are operated slowly to prevent watering out thus total fluid production is purposefully maintained at low volumes. There remain potential possibilities for development of geothermal fluids in the Williston Basin. Unitized fields in which water production from several tens of wells is collected at a single site are good possibilities for development. Water production in the unitized fields is greater than 1000 gpm is several areas. A similar possibility occurs where infill-drilling between Bakken and Three Forks horizontal wells has created areas where large volumes of geothermal fluids are available on multi-well pads and in unitized fields. Although the Bakken produces small amounts of water, the water/oil ration is typically less than 1, the oil and water mix produced at the well head can be sent through the heat exchanger on an ORC. It is estimated that several tens of MWh of power could be generated by a distributed system of ORC engines in the areas of high-density drilling in the Bakken Formation. Finally, horizontal drilling in water bearing formations is the other possibility. Several secondary recovery water-flood projects in the basin are producing water above 100 ⁰C at rates of 300 gpm to 850 gpm. Those systems also could produce several tens of MWh of power with ORC technology. Objective 3 of the project was highly successful. The program has produced 5 PhDs, 7 MS, and 3 BS students with theses in geothermal energy. The team has involved 7 faculty in 4 different engineering and science disciplines, ChE, EE, GE, and Geol. The team has

  10. Contribution of anaerobic digesters to emissions mitigation and electricity generation under U.S. climate policy.

    PubMed

    Zaks, David P M; Winchester, Niven; Kucharik, Christopher J; Barford, Carol C; Paltsev, Sergey; Reilly, John M

    2011-08-15

    Livestock husbandry in the U.S. significantly contributes to many environmental problems, including the release of methane, a potent greenhouse gas (GHG). Anaerobic digesters (ADs) break down organic wastes using bacteria that produce methane, which can be collected and combusted to generate electricity. ADs also reduce odors and pathogens that are common with manure storage and the digested manure can be used as a fertilizer. There are relatively few ADs in the U.S., mainly due to their high capital costs. We use the MIT Emissions Prediction and Policy Analysis (EPPA) model to test the effects of a representative U.S. climate stabilization policy on the adoption of ADs which sell electricity and generate methane mitigation credits. Under such policy, ADs become competitive at producing electricity in 2025, when they receive methane reduction credits and electricity from fossil fuels becomes more expensive. We find that ADs have the potential to generate 5.5% of U.S. electricity.

  11. Investigation of a generator system for generating electrical power, to supply directly to the public network, using a windmill

    NASA Technical Reports Server (NTRS)

    Tromp, C.

    1979-01-01

    A windpowered generator system is described which uses a windmill to convert mechanical energy to electrical energy for a three phase (network) voltage of constant amplitude and frequency. The generator system controls the windmill by the number of revolutions so that the power drawn from the wind for a given wind velocity is maximum. A generator revolution which is proportional to wind velocity is achieved. The stator of the generator is linked directly to the network and a feed converter at the rotor takes care of constant voltage and frequency at the stator.

  12. An integrated assessment of global and regional water demands for electricity generation to 2095

    SciTech Connect

    Davies, Evan; Kyle, G. Page; Edmonds, James A.

    2013-02-01

    Electric power plants currently account for approximately one-half of the global industrial water withdrawal. While continued expansion of the electric sector seems likely into the future, the consequent water demands are quite uncertain, and will depend on highly variable water intensities by electricity technologies, at present and in the future. Using GCAM, an integrated assessment model of energy, agriculture, and climate change, we first establish lower-bound, median, and upper-bound estimates for present-day electric sector water withdrawals and consumption by individual electric generation technologies in each of 14 geopolitical regions, and compare them with available estimates of regional industrial or electric sector water use. We then explore the evolution of global and regional electric sector water use over the next century, focusing on uncertainties related to withdrawal and consumption intensities for a variety of electric generation technologies, rates of change of power plant cooling system types, and rates of adoption of a suite of water-saving technologies. Results reveal that the water withdrawal intensity of electricity generation is likely to decrease in the near term with capital stock turnover, as wet towers replace once-through flow cooling systems and advanced electricity generation technologies replace conventional ones. An increase in consumptive use accompanies the decrease in water withdrawal rates; however, a suite of water conservation technologies currently under development could compensate for this increase in consumption. Finally, at a regional scale, water use characteristics vary significantly based on characteristics of the existing capital stock and the selection of electricity generation technologies into the future.

  13. Economic analysis of the use of wind power for electrical generation on midwestern dairy farms

    SciTech Connect

    Reinemann, D.J.; Koegel, R.G.; Straub, R.J.

    1982-12-01

    The optimum size WECS for dairy farm electrical production, and return on investment thereof depend greatly on utility regulations, load management techniques, and the future of the economy. Seasonal and daily fluctuations in available wind power and electric demand together with existing or expected rate schedules must be considered in choosing an appropriate load management system. An economic analysis is done investigating optimal system size and use strategies for the use of wind generated electrical power on midwestern dairy farms.

  14. Systematic Review and Harmonization of Life Cycle GHG Emission Estimates for Electricity Generation Technologies (Presentation)

    SciTech Connect

    Heath, G.

    2012-06-01

    This powerpoint presentation to be presented at the World Renewable Energy Forum on May 14, 2012, in Denver, CO, discusses systematic review and harmonization of life cycle GHG emission estimates for electricity generation technologies.

  15. 29 CFR 1910.269 - Electric power generation, transmission, and distribution.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 29 Labor 5 2014-07-01 2014-07-01 false Electric power generation, transmission, and distribution. 1910.269 Section 1910.269 Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR OCCUPATIONAL SAFETY AND HEALTH STANDARDS Special Industries § 1910.269 Electric power...

  16. 29 CFR 1910.269 - Electric power generation, transmission, and distribution.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 29 Labor 5 2013-07-01 2013-07-01 false Electric power generation, transmission, and distribution. 1910.269 Section 1910.269 Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR OCCUPATIONAL SAFETY AND HEALTH STANDARDS Special Industries § 1910.269 Electric power...

  17. 29 CFR 1910.269 - Electric power generation, transmission, and distribution.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 29 Labor 5 2011-07-01 2011-07-01 false Electric power generation, transmission, and distribution. 1910.269 Section 1910.269 Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR OCCUPATIONAL SAFETY AND HEALTH STANDARDS Special Industries § 1910.269 Electric power...

  18. MODULATING EMISSIONS FROM ELECTRIC GENERATING UNITS AS A FUNCTION OF METEOROLOGICAL VARIABLES

    EPA Science Inventory

    Electric Generating Units (EGUs) are an important source of emissions of nitrogen oxides (NOx), which react with volatile organic compounds (VOCs) in the presence of sunlight to form ozone. Emissions from EGUs are believed to vary depending on short-term demands for electricity;...

  19. Solar central electric power generation - A baseline design

    NASA Technical Reports Server (NTRS)

    Powell, J. C.

    1976-01-01

    The paper presents the conceptual technical baseline design of a solar electric power plant using the central receiver concept, and derives credible cost estimates from the baseline design. The major components of the plant - heliostats, tower, receiver, tower piping, and thermal storage - are discussed in terms of technical and cost information. The assumed peak plant output is 215 MW(e), over 4000 daylight hours. The contribution of total capital investment to energy cost is estimated to be about 55 mills per kwh in mid-1974 dollars.

  20. Assessing the Long-Term System Value of Intermittent Electric Generation Technologies

    SciTech Connect

    Lamont, A D

    2005-08-24

    This research investigates the economic penetration and system-wide effects of large-scale intermittent technologies in an electric generation system. The research extends the standard screening curve analysis to optimize the penetration and system structure with intermittent technologies. The analysis is based on hour-by-hour electric demands and intermittent generation. A theoretical framework is developed to find an expression for the marginal value of an intermittent technology as a function of the average system marginal cost, the capacity factor of the generator, and the covariance between the generator's hourly production and the hourly system marginal cost. A series of model runs are made examining the penetration of wind and photovoltaic in a simple electric generation system. These illustrate the conclusions in the theoretical analysis and illustrate the effects that large-scale intermittent penetration has on the structure of the generation system. In the long-term, adding intermittent generation to a system allows us to restructure the dispatchable generation capacity to a mix with lower capital cost. It is found that large scale intermittent generation tends to reduce the optimal capacity and production of baseload generators and increase the capacity and production of intermediate generators, although the extent to which this occurs depends strongly on the pattern of production from the intermediate generators. It is also shown that the marginal value of intermittent generation declines as it penetrates. The analysis investigates the specific mechanism through which this occurs.

  1. Microbial electricity generation in rice paddy fields: recent advances and perspectives in rhizosphere microbial fuel cells.

    PubMed

    Kouzuma, Atsushi; Kaku, Nobuo; Watanabe, Kazuya

    2014-12-01

    Microbial fuel cells (MFCs) are devices that use living microbes for the conversion of organic matter into electricity. MFC systems can be applied to the generation of electricity at water/sediment interfaces in the environment, such as bay areas, wetlands, and rice paddy fields. Using these systems, electricity generation in paddy fields as high as ∼80 mW m(-2) (based on the projected anode area) has been demonstrated, and evidence suggests that rhizosphere microbes preferentially utilize organic exudates from rice roots for generating electricity. Phylogenetic and metagenomic analyses have been conducted to identify the microbial species and catabolic pathways that are involved in the conversion of root exudates into electricity, suggesting the importance of syntrophic interactions. In parallel, pot cultures of rice and other aquatic plants have been used for rhizosphere MFC experiments under controlled laboratory conditions. The findings from these studies have demonstrated the potential of electricity generation for mitigating methane emission from the rhizosphere. Notably, however, the presence of large amounts of organics in the rhizosphere drastically reduces the effect of electricity generation on methane production. Further studies are necessary to evaluate the potential of these systems for mitigating methane emission from rice paddy fields. We suggest that paddy-field MFCs represent a promising approach for harvesting latent energy of the natural world.

  2. Generation of Electric and Magnetic Fields During Detonation of High Explosive Charges in Boreholes

    SciTech Connect

    Soloviev, S; Sweeney, J

    2004-06-04

    We present experimental results of a study of electromagnetic field generation during underground detonation of high explosive charges in holes bored in sandy loam and granite. Test conditions and physico-mechanical properties of the soil exert significant influence on the parameters of electromagnetic signals generated by underground TNT charges with masses of 2 - 200 kg. The electric and magnetic field experimental data are satisfactorily described by an electric dipole model with the source embedded in a layered media.

  3. Electric generator using a triangular diamagnetic levitating rotor system.

    PubMed

    Ho, Joe Nhut; Wang, Wei-Chih

    2009-02-01

    This paper describes a feasibility study of creating a small low friction and low maintenance generator using a diamagnetically stabilized levitating rotor. The planar rotor described in this paper uses a triangular configuration of magnets that generates emf by passing over coils placed below the rotor. Equations were developed to predict the generated emf from coils with two different coil geometries. Additionally, this paper provides a method for estimating optimal coil size and position for the planar rotor presented for both segmental arc and circular coils to obtain maximum power output. Experiments demonstrated that the emf generated in the coils matches well with the predicted wave forms for each case, and the optimization theory gives good prediction to outcome of induced waveforms. For the segmental arc coil design, the induced emf was 1.7 mV at a radial frequency of 21.8 rad/s. For the circular coil design, the emf was 1.25 mV at a radial frequency of 28.1 rad/s. PMID:19256668

  4. Development and bottlenecks of renewable electricity generation in China: a critical review.

    PubMed

    Hu, Yuanan; Cheng, Hefa

    2013-04-01

    This review provides an overview on the development and status of electricity generation from renewable energy sources, namely hydropower, wind power, solar power, biomass energy, and geothermal energy, and discusses the technology, policy, and finance bottlenecks limiting growth of the renewable energy industry in China. Renewable energy, dominated by hydropower, currently accounts for more than 25% of the total electricity generation capacity. China is the world's largest generator of both hydropower and wind power, and also the largest manufacturer and exporter of photovoltaic cells. Electricity production from solar and biomass energy is at the early stages of development in China, while geothermal power generation has received little attention recently. The spatial mismatch in renewable energy supply and electricity demand requires construction of long-distance transmission networks, while the intermittence of renewable energy poses significant technical problems for feeding the generated electricity into the power grid. Besides greater investment in research and technology development, effective policies and financial measures should also be developed and improved to better support the healthy and sustained growth of renewable electricity generation. Meanwhile, attention should be paid to the potential impacts on the local environment from renewable energy development, despite the wider benefits for climate change.

  5. Development and bottlenecks of renewable electricity generation in China: a critical review.

    PubMed

    Hu, Yuanan; Cheng, Hefa

    2013-04-01

    This review provides an overview on the development and status of electricity generation from renewable energy sources, namely hydropower, wind power, solar power, biomass energy, and geothermal energy, and discusses the technology, policy, and finance bottlenecks limiting growth of the renewable energy industry in China. Renewable energy, dominated by hydropower, currently accounts for more than 25% of the total electricity generation capacity. China is the world's largest generator of both hydropower and wind power, and also the largest manufacturer and exporter of photovoltaic cells. Electricity production from solar and biomass energy is at the early stages of development in China, while geothermal power generation has received little attention recently. The spatial mismatch in renewable energy supply and electricity demand requires construction of long-distance transmission networks, while the intermittence of renewable energy poses significant technical problems for feeding the generated electricity into the power grid. Besides greater investment in research and technology development, effective policies and financial measures should also be developed and improved to better support the healthy and sustained growth of renewable electricity generation. Meanwhile, attention should be paid to the potential impacts on the local environment from renewable energy development, despite the wider benefits for climate change. PMID:23445126

  6. Generation of pure electrical quadrature amplitude modulation with photonic vector modulator.

    PubMed

    Corral, Juan L; Sambaraju, Rakesh; Piqueras, Miguel A; Polo, Valentín

    2008-06-15

    A photonic vector modulator architecture for generating pure quadrature amplitude modulation (QAM) signals is presented. An electrical quadrature-modulated signal at microwave-millimeter-wave frequencies is generated from its corresponding baseband in-phase (I) and quadrature (Q) components. In the proposed scheme, no electrical devices apart from the electrical tone oscillator are needed in the generation process. In addition, the purity of the generated signal is increased, and the hardware requirements are reduced when compared with previously proposed architectures so a highly compact low-cost architecture can be implemented. A pure 1.25 Gbit/s 4-QAM signal has been experimentally generated at a 42 GHz carrier frequency.

  7. Substrates and pathway of electricity generation in a nitrification-based microbial fuel cell.

    PubMed

    Chen, Hui; Zheng, Ping; Zhang, Jiqiang; Xie, Zuofu; Ji, Junyuan; Ghulam, Abbas

    2014-06-01

    Nitrification-based microbial fuel cell (N-MFC) is a novel inorganic microbial fuel cell based on nitrification in the anode compartment. So far, little information is available on the substrates and pathway of N-MFC. The results of this study indicated that apart from the primary nitrification substrate (ammonium), the intermediates (hydroxylamine and nitrite) could also serve as anodic fuel to generate current, and the end product nitrate showed an inhibitory effect on electricity generation. Based on the research, a pathway of electricity generation was proposed for N-MFC: ammonium was oxidized first to nitrite by ammonia-oxidizing bacteria (AOB), then the nitrite in anolyte and the potassium permanganate in catholyte constituted a chemical cell to generate current. In other words, the electricity generation in N-MFC was not only supported by microbial reaction as we expected, but both biological and electrochemical reactions contributed.

  8. Future trends in electrical energy generation economics in the United States

    NASA Technical Reports Server (NTRS)

    Schmitt, R. W.; Fox, G. R.; Shah, R. P.; Stewart, P. J.; Vermilyea, D. A.

    1977-01-01

    Developments related to the economics of coal-fired systems in the U.S. are mainly considered. The historical background of the U.S. electric generation industry is examined and the U.S. electrical generation characteristics in the year 1975 are considered. It is pointed out that coal-fired power plants are presently the largest source of electrical energy generation in the U.S. Questions concerning the availability and quality of coal are investigated. Currently there are plans for converting some 50 large oil and gas-fired generating plants to coal, and it is expected that coal will be the fuel used in almost all fossil-fired base load additions to generating capacity. Aspects of advanced energy conversion from coal are discussed, taking into account the performance and economic potential of the energy conversion systems.

  9. 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.

  10. Solar thermal bowl concepts and economic comparisons for electricity generation

    SciTech Connect

    Williams, T.A.; Dirks, J.A.; Brown, D.R.; Antoniak, Z.I.; Allemann, R.T.; Coomes, E.P.; Craig, S.N.; Drost, M.K.; Humphreys, K.K.; Nomura, K.K.

    1988-04-01

    This study is aimed at providing a relative comparison of the thermodynamic and economic performance in electric applications for fixed mirror distributed focus (FMDF) solar thermal concepts which have been studied and developed in the DOE solar thermal program. Following the completion of earlier systems comparison studies in the late 1970's there have been a number of years of progress in solar thermal technology. This progress includes developing new solar components, improving component and system design details, constructing working systems, and collecting operating data on the systems. This study povides an update of the expected performance and cost of the major components, and an overall system energy cost for the FMDDF concepts evaluated. The projections in this study are for the late 1990's and are based on the potential capabilities that might be achieved with further technology development.

  11. A Solar Thermophotovoltaic Electric Generator for Remote Power Applications

    NASA Technical Reports Server (NTRS)

    Fatemi, Navid S.

    1998-01-01

    We have successfully demonstrated that a solar thermophotovoltaic (TPV) system with a SiC graybody emitter and the monolithic interconnected module device technology can be realized. A custom-designed solar cavity was made to house the SiC emitter and the MIM strings for testing in a Stirling dish solar concentrator. Five 1x1-cm MIMs, with a bandgap of 0.74 eV,were mounted on a specially designed water-cooled heatsink and were electrically connected in series to form a string. Two such strings were fabricated and tested, as well as high-performance 2x2-cm MIMs with a bandgap of 0.74 eV. Very high output power density values between 0.82 and 0.90 W/sq cm were observed for an average emitter temperature of 1501 K.

  12. A Solar Thermophotovoltaic Electric Generator for Remote Power Applications

    NASA Technical Reports Server (NTRS)

    Fatemi, Navid S.

    1998-01-01

    We have successfully demonstrated that a solar thermophotovoltaic (TPV) system with a SiC graybody emitter and the monolithic interconnected module device technology can be realized. A custom-designed solar cavity was made to house the SiC emitter and the Monolithic Integrated Module (MIM) strings for testing in a Stirling dish solar concentrator. Five 1x1-cm MIMs, with a bandgap of 0.74 eV, were mounted on a specially designed water-cooled heatsink and were electrically connected in series to form a string. Two such strings were fabricated and tested, as well as high-performance 2x2-cm MIMs with a bandgap of 0.74 eV. Very high output power density values between 0.82 and 0.90 W/ square cm were observed for an average emitter temperature of 1501 K.

  13. Preliminary estimates of electrical generating capacity of slim holes--a theoretical approach

    SciTech Connect

    Pritchett, John W.

    1995-01-26

    The feasibility of using small geothermal generators (< 1 MWe) for off-grid electrical power in remote areas or for rural electrification in developing nations would be enhanced if drilling costs could be reduced. This paper examines the electrical generating capacity of fluids which can be produced from typical slim holes (six-inch diameter or less), both by binary techniques (with downhole pumps) and, for hotter reservoir fluids, by conventional spontaneous-discharge flash-steam methods. Depending mainly on reservoir temperature, electrical capacities from a few hundred kilowatts to over one megawatt per slim hole appear to be possible.

  14. Water withdrawal and consumption reduction analysis for electrical energy generation system

    NASA Astrophysics Data System (ADS)

    Nouri, Narjes

    There is an increasing concern over shrinking water resources. Water use in the energy sector primarily occurs in electricity generation. Anticipating scarcer supplies, the value of water is undoubtedly on the rise and design, implementation, and utilization of water saving mechanisms in energy generation systems are becoming inevitable. Most power plants generate power by boiling water to produce steam to spin electricity-generating turbines. Large quantities of water are often used to cool the steam in these plants. As a consequence, most fossil-based power plants in addition to consuming water, impact the water resources by raising the temperature of water withdrawn for cooling. A comprehensive study is conducted in this thesis to analyze and quantify water withdrawals and consumption of various electricity generation sources such as coal, natural gas, renewable sources, etc. Electricity generation for the state of California is studied and presented as California is facing a serious drought problem affecting more than 30 million people. Integrated planning for the interleaved energy and water sectors is essential for both water and energy savings. A linear model is developed to minimize the water consumption while considering several limitations and restrictions. California has planned to shut down some of its hydro and nuclear plants due to environmental concerns. Studies have been performed for various electricity generation and water saving scenarios including no-hydro and no-nuclear plant and the results are presented. Modifications to proposed different scenarios have been applied and discussed to meet the practical and reliability constraints.

  15. Generation of an ultra-short electrical pulse with width shorter than the excitation laser

    PubMed Central

    Shi, Wei; Wang, Shaoqiang; Ma, Cheng; Xu, Ming

    2016-01-01

    We demonstrate experimentally a rare phenomenon that the width of an electrical response is shorter than that of the excitation laser. In this work, generation of an ultrashort electrical pulse is by a semi-insulating GaAs photoconductive semiconductor switch (PCSS) and the generated electrical pulse width is shorter than that of the excitation laser from diode laser. When the pulse width and energy of the excitation laser are fixed at 25.7 ns and 1.6 μJ respectively, the width of the generated electrical pulse width by 3-mm-gap GaAs PCSS at the bias voltage of 9 kV is only 7.3 ns. The model of photon-activated charge domain (PACD) is used to explain the peculiar phenomenon in our experiment. The ultrashort electrical pulse width is mainly relevant to the time interval of PACD from occurrence to disappearance in the mode. The shorter the time interval is, the narrower the electrical pulse width will become. In more general terms, our result suggests that in nonlinear regime a response signal can have a much short width than the excitation pulses. The result clearly indicates that generating ultrashort electrical pulses can be achieved without the need of ultrashort lasers. PMID:27273512

  16. Development of a dynamometer for an integrated-starter-generator (ISG) motor used in electric vehicles

    NASA Astrophysics Data System (ADS)

    Wang, Zai-zhou; Zhang, Cheng-ning; Song, Qiang; Zhang, Chun-xiang

    2008-12-01

    Hybrid-Electric Vehicle (HEV) which combined the electric motor with auxiliary power unit in a car driven is introduced. Characteristic of Hybrid-Electric Vehicle are different from the other vehicle, in the structure of Hybrid-Electric Vehicle, Integrated Starter Generator (ISG) electrical system can achieve high efficient performance of driving and generating electricity simultaneously. These systems adopt the sum torque through engine and generator, the motor connected transmission through engine. According to the requirements of different conditions, the torque of motor and transmission are compound in various forms to achieve optimal driving efficiency.This study developed a dynamometer to measure the relationship between locked torques with temperature rises of an Integrated Starter Generator motor used in electrical vehicles. The dynamometer adopted an AC motor to obtain the relationship between drive and load functions, which developed in this study can perform real-time measurements and storage of measured data obtained from the dynamometer. Experiments for measuring temperature rise of ISG motor were performed at three different conditions, namely 56 Nm locked rotor torques and 18.8A locked rotor current; 57.1Nm constant torque at 1050rpm; constant power with 14.3Nm and 4050rpm, respectively. Based on the theory of temperature rise, the temperature rises of motor are 14K, 33.1K, and 16.01K for the tested cases respectively. Measured results show that the performance of motor system is satisfied with the design.

  17. Role of Energy Storage with Renewable Electricity Generation (Report Summary) (Presentation)

    SciTech Connect

    Denholm, P.; Ela, E.; Kirby, B.; Milligan, M.

    2010-03-01

    Renewable energy sources, such as wind and solar, have vast potential to reduce dependence on fossil fuels and greenhouse gas emissions in the electric sector. Climate change concerns, state initiatives including renewable portfolio standards, and consumer efforts are resulting in increased deployments of both technologies. Both solar photovoltaics (PV) and wind energy have variable and uncertain (sometimes referred to as "intermittent") output, which are unlike the dispatchable sources used for the majority of electricity generation in the United States. The variability of these sources has led to concerns regarding the reliability of an electric grid that derives a large fraction of its energy from these sources as well as the cost of reliably integrating large amounts of variable generation into the electric grid. In this report, we explore the role of energy storage in the electricity grid, focusing on the effects of large-scale deployment of variable renewable sources (primarily wind and solar energy).

  18. Implantable power generation system utilizing muscle contractions excited by electrical stimulation.

    PubMed

    Sahara, Genta; Hijikata, Wataru; Tomioka, Kota; Shinshi, Tadahiko

    2016-06-01

    An implantable power generation system driven by muscle contractions for supplying power to active implantable medical devices, such as pacemakers and neurostimulators, is proposed. In this system, a muscle is intentionally contracted by an electrical stimulation in accordance with the demands of the active implantable medical device for electrical power. The proposed system, which comprises a small electromagnetic induction generator, electrodes with an electrical circuit for stimulation and a transmission device to convert the linear motion of the muscle contractions into rotational motion for the magneto rotor, generates electrical energy. In an ex vivo demonstration using the gastrocnemius muscle of a toad, which was 28 mm in length and weighed 1.3 g, the electrical energy generated by the prototype exceeded the energy consumed for electrical stimulation, with the net power being 111 µW. It was demonstrated that the proposed implantable power generation system has the potential to replace implantable batteries for active implantable medical devices.

  19. Implantable power generation system utilizing muscle contractions excited by electrical stimulation.

    PubMed

    Sahara, Genta; Hijikata, Wataru; Tomioka, Kota; Shinshi, Tadahiko

    2016-06-01

    An implantable power generation system driven by muscle contractions for supplying power to active implantable medical devices, such as pacemakers and neurostimulators, is proposed. In this system, a muscle is intentionally contracted by an electrical stimulation in accordance with the demands of the active implantable medical device for electrical power. The proposed system, which comprises a small electromagnetic induction generator, electrodes with an electrical circuit for stimulation and a transmission device to convert the linear motion of the muscle contractions into rotational motion for the magneto rotor, generates electrical energy. In an ex vivo demonstration using the gastrocnemius muscle of a toad, which was 28 mm in length and weighed 1.3 g, the electrical energy generated by the prototype exceeded the energy consumed for electrical stimulation, with the net power being 111 µW. It was demonstrated that the proposed implantable power generation system has the potential to replace implantable batteries for active implantable medical devices. PMID:27006422

  20. Feasibility Study of Biomass Electrical Generation on Tribal Lands

    SciTech Connect

    Tom Roche; Richard Hartmann; Joohn Luton; Warren Hudelson; Roger Blomguist; Jan Hacker; Colene Frye

    2005-03-29

    The goals of the St. Croix Tribe are to develop economically viable energy production facilities using readily available renewable biomass fuel sources at an acceptable cost per kilowatt hour ($/kWh), to provide new and meaningful permanent employment, retain and expand existing employment (logging) and provide revenues for both producers and sellers of the finished product. This is a feasibility study including an assessment of available biomass fuel, technology assessment, site selection, economics viability given the foreseeable fuel and generation costs, as well as an assessment of the potential markets for renewable energy.

  1. Contribution of longitudinal electric field of a gaussian beam to second harmonic generation

    NASA Astrophysics Data System (ADS)

    Mishra, S. R.; Rustagi, K. C.

    1990-01-01

    A laser beam with a nonuniform transverse intensity profile necessarily has a longitudinal component of the electric field. We show that a detectable second harmonic can be generated due to coupling of this longitudinal component with the transverse field of a gaussian beam in a configuration in which second harmonic generation is forbidden for plane wave interaction.

  2. Bringing electricity reform to the Philippines

    SciTech Connect

    Fe Villamejor-Mendoza, Maria

    2008-12-15

    Electricity reforms will not translate to competition overnight. But reforms are inching their way forward in institutions and stakeholders of the Philippine electricity industry, through regulatory and competition frameworks, processes, and systems promulgated and implemented. (author)

  3. Effects of furan derivatives and phenolic compounds on electricity generation in microbial fuel cells

    NASA Astrophysics Data System (ADS)

    Catal, Tunc; Fan, Yanzhen; Li, Kaichang; Bermek, Hakan; Liu, Hong

    Lignocellulosic biomass is an attractive fuel source for MFCs due to its renewable nature and ready availability. Furan derivatives and phenolic compounds could be potentially formed during the pre-treatment process of lignocellulosic biomass. In this study, voltage generation from these compounds and the effects of these compounds on voltage generation from glucose in air-cathode microbial fuel cells (MFCs) were examined. Except for 5-hydroxymethyl furfural (5-HMF), all the other compounds tested were unable to be utilized directly for electricity production in MFCs in the absence of other electron donors. One furan derivate, 5-HMF and two phenolic compounds, trans-cinnamic acid and 3,5-dimethoxy-4-hydroxy-cinnamic acid did not affect electricity generation from glucose at a concentration up to 10 mM. Four phenolic compounds, including syringaldeyhde, vanillin, trans-4-hydroxy-3-methoxy, and 4-hydroxy cinnamic acids inhibited electricity generation at concentrations above 5 mM. Other compounds, including 2-furaldehyde, benzyl alcohol and acetophenone, inhibited the electricity generation even at concentrations less than 0.2 mM. This study suggests that effective electricity generation from the hydrolysates of lignocellulosic biomass in MFCs may require the employment of the hydrolysis methods with low furan derivatives and phenolic compounds production, or the removal of some strong inhibitors prior to the MFC operation, or the improvement of bacterial tolerance against these compounds through the enrichment of new bacterial cultures or genetic modification of the bacterial strains.

  4. Native American Technical Assistance and Training for Renewable Energy Resource Development and Electrical Generation Facilities Management

    SciTech Connect

    A. David Lester

    2008-10-17

    The Council of Energy Resource Tribes (CERT) will facilitate technical expertise and training of Native Americans in renewable energy resource development for electrical generation facilities, and distributed generation options contributing to feasibility studies, strategic planning and visioning. CERT will also provide information to Tribes on energy efficiency and energy management techniques.This project will provide facilitation and coordination of expertise from government agencies and private industries to interact with Native Americans in ways that will result in renewable energy resource development, energy efficiency program development, and electrical generation facilities management by Tribal entities. The intent of this cooperative agreement is to help build capacity within the Tribes to manage these important resources.

  5. Space shuttle electrical power generation and reactant supply system

    NASA Technical Reports Server (NTRS)

    Simon, W. E.

    1985-01-01

    The design philosophy and development experience of fuel cell power generation and cryogenic reactant supply systems are reviewed, beginning with the state of technology at the conclusion of the Apollo Program. Technology advancements span a period of 10 years from initial definition phase to the most recent space transportation system (STS) flights. The development program encompassed prototype, verification, and qualification hardware, as well as post-STS-1 design improvements. Focus is on the problems encountered, the scientific and engineering approaches employed to meet the technological challenges, and the results obtained. Major technology barriers are discussed, and the evolving technology development paths are traced from their conceptual beginnings to the fully man-rated systems which are now an integral part of the shuttle vehicle.

  6. Electric probe investigations of microwave generated, atmospheric pressure, plasma jets

    SciTech Connect

    Porteanu, H. E.; Kuehn, S.; Gesche, R.

    2010-07-15

    We examine the applicability of the Langmuir-type of characterization for atmospheric pressure plasma jets generated in a millimeter-size cavity microwave resonator at 2.45 GHz. Wide range I-V characteristics of helium, argon, nitrogen, air and oxygen are presented for different gas fluxes, distances probe-resonator, and microwave powers. A detailed analysis is performed for the fine variation in the current around the floating potential. A simplified theory specially developed for this case is presented, considering the ionic and electronic saturation currents and the floating potential. Based on this theory, we conclude that, while the charge carrier density depends on gas flow, distance to plasma source, and microwave absorbed power, the electron temperature is quite independent of these parameters. The resulting plasma parameters for helium, argon, and nitrogen are presented.

  7. Method and apparatus for generating electric power by waves

    SciTech Connect

    Watabe, T.; Dote, Y.; Kondo, H.; Matsuda, T.; Takagi, M.; Yano, K.

    1984-12-25

    At least one caisson which is part or all of a breakwater forms a water chamber therein whose closure is a pendulum having a natural period in rocking or oscillating the same as a period of stationary wave surges caused in the water chamber by rocking movement of the pendulum owing to wave force impinging against the pendulum. At least one double-acting piston and cylinder assembly is connected to the pendulum, so that when a piston of the assembly is reciprocatively moved by the pendulum, pressure difference between cylinder chambers on both sides of the piston of the assembly controls a change-over valve which in turn controls hydraulic pressure discharged from the cylinder chambers to be supplied to a plurality of hydraulic motors respectively having accumulators of a type wherein accumulated pressure and volume of the hydraulic liquid are proportional to each other, whereby driving a common generator alternately by the hydraulic motors.

  8. Technology survey of electrical power generation and distribution for MIUS application

    NASA Technical Reports Server (NTRS)

    Gill, W. L.; Redding, T. E.

    1975-01-01

    Candidate electrical generation power systems for the modular integrated utility systems (MIUS) program are described. Literature surveys were conducted to cover both conventional and exotic generators. Heat-recovery equipment associated with conventional power systems and supporting equipment are also discussed. Typical ranges of operating conditions and generating efficiencies are described. Power distribution is discussed briefly. Those systems that appear to be applicable to MIUS have been indicated, and the criteria for equipment selection are discussed.

  9. Electricity generation by anaerobic bacteria and anoxic sediments from hypersaline soda lakes.

    PubMed

    Miller, Laurence G; Oremland, Ronald S

    2008-11-01

    Anaerobic bacteria and anoxic sediments from soda lakes produced electricity in microbial fuel cells (MFCs). No electricity was generated in the absence of bacterial metabolism. Arsenate respiring bacteria isolated from moderately hypersaline Mono Lake (Bacillus selenitireducens), and salt-saturated Searles Lake, CA (strain SLAS-1) oxidized lactate using arsenate as the electron acceptor. However, these cultures grew equally well without added arsenate using the MFC anode as their electron acceptor, and in the process oxidized lactate more efficiently. The decrease in electricity generation by consumption of added alternative electron acceptors (i.e. arsenate) which competed with the anode for available electrons proved to be a useful indicator of microbial activity and hence life in the fuel cells. Shaken sediment slurries from these two lakes also generated electricity, with or without added lactate. Hydrogen added to sediment slurries was consumed but did not stimulate electricity production. Finally, electricity was generated in statically incubated "intact" sediment cores from these lakes. More power was produced in sediment from Mono Lake than from Searles Lake, however microbial fuel cells could detect low levels of metabolism operating under moderate and extreme conditions of salt stress.

  10. Electricity generation by anaerobic bacteria and anoxic sediments from hypersaline soda lakes

    USGS Publications Warehouse

    Miller, L.G.; Oremland, R.S.

    2008-01-01

    Anaerobic bacteria and anoxic sediments from soda lakes produced electricity in microbial fuel cells (MFCs). No electricity was generated in the absence of bacterial metabolism. Arsenate respiring bacteria isolated from moderately hypersaline Mono Lake (Bacillus selenitireducens), and salt-saturated Searles Lake, CA (strain SLAS-1) oxidized lactate using arsenate as the electron acceptor. However, these cultures grew equally well without added arsenate using the MFC anode as their electron acceptor, and in the process oxidized lactate more efficiently. The decrease in electricity generation by consumption of added alternative electron acceptors (i.e. arsenate) which competed with the anode for available electrons proved to be a useful indicator of microbial activity and hence life in the fuel cells. Shaken sediment slurries from these two lakes also generated electricity, with or without added lactate. Hydrogen added to sediment slurries was consumed but did not stimulate electricity production. Finally, electricity was generated in statically incubated "intact" sediment cores from these lakes. More power was produced in sediment from Mono Lake than from Searles Lake, however microbial fuel cells could detect low levels of metabolism operating under moderate and extreme conditions of salt stress. ?? 2008 US Government.

  11. An Overnight Success?: Usage Patterns and Demographics of Academic Library Patrons during the Overnight Period from 11 p.m.-8 a.m.

    ERIC Educational Resources Information Center

    Sanders, Mark; Hodges, Chris

    2014-01-01

    During the Fall 2013 semester East Carolina University's main library piloted 24/5 hours of operation by opening on Sunday morning and not closing until Friday night. This article details the planning and execution of the pilot program, as well the findings from the data collected during the overnight period by people-counting cameras and a…

  12. Current and future greenhouse gas emissions associated with electricity generation in China: implications for electric vehicles.

    PubMed

    Shen, Wei; Han, Weijian; Wallington, Timothy J

    2014-06-17

    China's oil imports and greenhouse gas (GHG) emissions have grown rapidly over the past decade. Addressing energy security and GHG emissions is a national priority. Replacing conventional vehicles with electric vehicles (EVs) offers a potential solution to both issues. While the reduction in petroleum use and hence the energy security benefits of switching to EVs are obvious, the GHG benefits are less obvious. We examine the current Chinese electric grid and its evolution and discuss the implications for EVs. China's electric grid will be dominated by coal for the next few decades. In 2015 in Beijing, Shanghai, and Guangzhou, EVs will need to use less than 14, 19, and 23 kWh/100 km, respectively, to match the 183 gCO2/km WTW emissions for energy saving vehicles. In 2020, in Beijing, Shanghai, and Guangzhou EVs will need to use less than 13, 18, and 20 kWh/100 km, respectively, to match the 137 gCO2/km WTW emissions for energy saving vehicles. EVs currently demonstrated in China use 24-32 kWh/100 km. Electrification will reduce petroleum imports; however, it will be very challenging for EVs to contribute to government targets for GHGs emissions reduction.

  13. Treatment of Solar Generation in Electric Utility Resource Planning

    SciTech Connect

    Sterling, J.; McLaren, J.; Taylor, M.; Cory, K.

    2013-10-01

    Today's utility planners have a different market and economic context than their predecessors, including planning for the growth of renewable energy. State and federal support policies, solar photovoltaic (PV) price declines, and the introduction of new business models for solar PV 'ownership' are leading to increasing interest in solar technologies (especially PV); however, solar introduces myriad new variables into the utility resource planning decision. Most, but not all, utility planners have less experience analyzing solar than conventional generation as part of capacity planning, portfolio evaluation, and resource procurement decisions. To begin to build this knowledge, utility staff expressed interest in one effort: utility exchanges regarding data, methods, challenges, and solutions for incorporating solar in the planning process. Through interviews and a questionnaire, this report aims to begin this exchange of information and capture utility-provided information about: 1) how various utilities approach long-range resource planning; 2) methods and tools utilities use to conduct resource planning; and, 3) how solar technologies are considered in the resource planning process.

  14. [Electricity generation and contaminants degradation performances of a microbial fuel cell fed with Dioscorea zingiberensis wastewater].

    PubMed

    Li, Hui; Zhu, Xiu-Ping; Xu, Nan; Ni, Jin-Ren

    2011-01-01

    The electricity generation performance of a microbial fuel cell (MFC) utilizing Dioscorea zingiberensis wastewater was studied with an H-shape reactor. Indexes including pH, conductivity, oxidation peak potential and chemical oxygen demand (COD) of the anolyte were monitored to investigate the contaminants degradation performance of the MFC during the electricity generation process, besides, contaminant ingredients in anodic influent and effluent were analyzed by GC-MS and IR spectra as well. The maximum power density of the MFC could achieve 118.1 mW/m2 and the internal resistance was about 480 omega. Connected with a 1 000 omega external resistance, the output potential was about 0.4 V. Fed with 5 mL Dioscorea zingiberensis wastewater, the electricity generation lasted about 133 h and the coulombic efficiency was about 3.93%. At the end of electricity generation cycle, COD decreased by 90.1% while NH4(+) -N decreased by 66.8%. Furfural compounds, phenols and some other complicated organics could be decomposed and utilized in the electricity generation process, and the residual contaminants in effluent included some long-chain fatty acids, esters, ethers, and esters with benzene ring, cycloalkanes, cycloolefins, etc. The results indicate that MFC, which can degrade and utilize the organic contaminants in Dioscorea zingiberensis wastewater simultaneously, provides a new approach for resource recovery treatment of Dioscorea zingiberensis wastewater.

  15. The generation of pollution-free electrical power from solar energy.

    NASA Technical Reports Server (NTRS)

    Cherry, W. R.

    1971-01-01

    Projections of the U.S. electrical power demands over the next 30 years indicate that the U.S. could be in grave danger from power shortages, undesirable effluence, and thermal pollution. An appraisal of nonconventional methods of producing electrical power is conducted, giving particular attention to the conversion of solar energy into commercial quantities of electrical power by solar cells. It is found that 1% of the land area of the 48 states could provide the total electrical power requirements of the U.S. in the year 1990. The ultimate method of generating vast quantities of electrical power would be from a series of synchronous satellites which beam microwave power back to earth to be used wherever needed. Present high manufacturing costs of solar cells could be substantially reduced by using massive automated techniques employing abundant low cost materials.

  16. Approaches for controlling air pollutants and their environmental impacts generated from coal-based electricity generation in China.

    PubMed

    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.

  17. Simultaneous anaerobic sulfide and nitrate removal coupled with electricity generation in Microbial Fuel Cell.

    PubMed

    Cai, Jing; Zheng, Ping; Zhang, Jiqiang; Xie, Zuofu; Li, Wei; Sun, Peide

    2013-02-01

    Two-chamber Microbial Fuel Cells (MFC) using graphite rods as electrodes were operated for simultaneous anaerobic sulfide and nitrate removal coupled with electricity generation. The MFC showed good ability to remove substrates. When the influent sulfide and nitrate concentrations were 780 mg/L and 135.49 mg/L, respectively, the removal percentages of sulfide and nitrate were higher than 90% and the main end products were nitrogen and sulfate. The MFC also showed good ability to generate electricity, and the voltage went up with the rise of influent substrate concentrations. When the external resistance was 1000 Ω, its highest steady voltage was 71 mV. Based on the linear relationship between the electrons released by substrates and accepted by electrode, it was concluded that the electricity generation was coupled with the substrate conversion in the MFC.

  18. Characteristics of electricity generation and biodegradation in tidal river sludge-used microbial fuel cells.

    PubMed

    Touch, Narong; Hibino, Tadashi; Nagatsu, Yoshiyuki; Tachiuchi, Kouhei

    2014-04-01

    The electricity generation behavior of microbial fuel cell (MFC) using the sludge collected from the riverbank of a tidal river, and the biodegradation of the sludge by the electricity generation are evaluated. Although the maximum current density (150-300 mA/m(2)) was higher than that of MFC using freshwater sediment (30 mA/m(2)), the output current was greatly restricted by the mass transfer limitation. However, our results also indicate that placing the anode in different locations in the sludge could reduce the mass transfer limitation. After approximately 3 months, the removal efficiency of organic carbon was approximately 10%, demonstrated that MFC could also enhance the biodegradation of the sludge by nearly 10-fold comparing with the natural biodegradation. We also found that the biodegradation could be identified by the behavior of oxygen consumption of the sludge. Importantly, the oxygen consumption of the sludge became higher along with the electricity generation.

  19. Variable Renewable Generation can Provide Balancing Control to the Electric Power System (Fact Sheet)

    SciTech Connect

    Not Available

    2013-09-01

    As wind and solar plants become more common in the electric power system, they may be called on to provide grid support services to help maintain system reliability. For example, through the use of inertial response, primary frequency response, and automatic generation control (also called secondary frequency response), wind power can provide assistance in balancing the generation and load on the system. These active power (i.e., real power) control services have the potential to assist the electric power system in times of disturbances and during normal conditions while also potentially providing economic value to consumers and variable renewable generation owners. This one-page, two-sided fact sheet discusses the grid-friendly support and benefits renewables can provide to the electric power system.

  20. Single channel double-duct liquid metal electrical generator using a magnetohydrodynamic device

    DOEpatents

    Haaland, C.M.; Deeds, W.E.

    1999-07-13

    A single channel double-duct liquid metal electrical generator using a magnetohydrodynamic (MHD) device. The single channel device provides useful output AC electric energy. The generator includes a two-cylinder linear-piston engine which drives liquid metal in a single channel looped around one side of the MHD device to form a double-duct contra-flowing liquid metal MHD generator. A flow conduit network and drive mechanism are provided for moving liquid metal with an oscillating flow through a static magnetic field to produce useful AC electric energy at practical voltages and currents. Variable stroke is obtained by controlling the quantity of liquid metal in the channel. High efficiency is obtained over a wide range of frequency and power output. 5 figs.

  1. Single channel double-duct liquid metal electrical generator using a magnetohydrodynamic device

    DOEpatents

    Haaland, Carsten M.; Deeds, W. Edward

    1999-01-01

    A single channel double-duct liquid metal electrical generator using a magnetohydrodynamic (MHD) device. The single channel device provides useful output AC electric energy. The generator includes a two-cylinder linear-piston engine which drives liquid metal in a single channel looped around one side of the MHD device to form a double-duct contra-flowing liquid metal MHD generator. A flow conduit network and drive mechanism are provided for moving liquid metal with an oscillating flow through a static magnetic field to produce useful AC electric energy at practical voltages and currents. Variable stroke is obtained by controlling the quantity of liquid metal in the channel. High efficiency is obtained over a wide range of frequency and power output.

  2. Microbial communities involved in electricity generation from sulfide oxidation in a microbial fuel cell.

    PubMed

    Sun, Min; Tong, Zhong-Hua; Sheng, Guo-Ping; Chen, Yong-Zhen; Zhang, Feng; Mu, Zhe-Xuan; Wang, Hua-Lin; Zeng, Raymond J; Liu, Xian-Wei; Yu, Han-Qing; Wei, Li; Ma, Fang

    2010-10-15

    Simultaneous electricity generation and sulfide removal can be achieved in a microbial fuel cell (MFC). In electricity harvesting from sulfide oxidation in such an MFC, various microbial communities are involved. It is essential to elucidate the microbial communities and their roles in the sulfide conversion and electricity generation. In this work, an MFC was constructed to enrich a microbial consortium, which could harvest electricity from sulfide oxidation. Electrochemical analysis demonstrated that microbial catalysis was involved in electricity output in the sulfide-fed MFC. The anode-attached and planktonic communities could perform catalysis independently, and synergistic interactions occurred when the two communities worked together. A 16S rRNA clone library analysis was employed to characterize the microbial communities in the MFC. The anode-attached and planktonic communities shared similar richness and diversity, while the LIBSHUFF analysis revealed that the two community structures were significantly different. The exoelectrogenic, sulfur-oxidizing and sulfate-reducing bacteria were found in the MFC anodic chamber. The discovery of these bacteria was consistent with the community characteristics for electricity generation from sulfide oxidation. The exoelectrogenic bacteria were found both on the anode and in the solution. The sulfur-oxidizing bacteria were present in greater abundance on the anode than in the solution, while the sulfate-reducing bacteria preferably lived in the solution.

  3. Developing a tool to estimate water withdrawal and consumption in electricity generation in the United States.

    SciTech Connect

    Wu, M.; Peng, J.

    2011-02-24

    Freshwater consumption for electricity generation is projected to increase dramatically in the next couple of decades in the United States. The increased demand is likely to further strain freshwater resources in regions where water has already become scarce. Meanwhile, the automotive industry has stepped up its research, development, and deployment efforts on electric vehicles (EVs) and plug-in hybrid electric vehicles (PHEVs). Large-scale, escalated production of EVs and PHEVs nationwide would require increased electricity production, and so meeting the water demand becomes an even greater challenge. The goal of this study is to provide a baseline assessment of freshwater use in electricity generation in the United States and at the state level. Freshwater withdrawal and consumption requirements for power generated from fossil, nonfossil, and renewable sources via various technologies and by use of different cooling systems are examined. A data inventory has been developed that compiles data from government statistics, reports, and literature issued by major research institutes. A spreadsheet-based model has been developed to conduct the estimates by means of a transparent and interactive process. The model further allows us to project future water withdrawal and consumption in electricity production under the forecasted increases in demand. This tool is intended to provide decision makers with the means to make a quick comparison among various fuel, technology, and cooling system options. The model output can be used to address water resource sustainability when considering new projects or expansion of existing plants.

  4. Electric field-induced second harmonic generation studies of chromophore orientational dynamics in photorefractive polymers

    NASA Astrophysics Data System (ADS)

    Ostroverkhova, Oksana; Stickrath, Andrew; Singer, Kenneth D.

    2002-06-01

    Photorefractive (PR) polymers are promising for use in various applications that require fast response times. The main factors that determine the PR speed in polymers are photoconductivity and chromophore reorientation in an electric field. In this article, we investigate the chromophore reorientational dynamics in various PR composites using the electric field second harmonic generation (EFISHG) technique, and then relate it to the PR dynamics observed in a four-wave mixing holographic experiment. We also report on the enhancement of the EFISHG signal in the presence of HeNe light, which we attribute to a photoinduced internal electric field that formed in the PR polymer.

  5. A high-bandwidth electrical waveform generator based on an aperture-coupled stripline

    SciTech Connect

    Skeldon, M. D.

    2000-09-01

    An electrical waveform generator based on an aperture-coupled stripline is described. The device is a four-port electrical directional coupler consisting of two striplines coupled through an aperture in their common ground plane. Replacing the aperture layer of the device can produce arbitrarily shaped electrical waveforms with 100 ps structure over a pulse envelope of several nanoseconds. A numerical solution of the telegraph equations using the method of characteristics is used to model and design devices. Excellent agreement is obtained between the model and device performance. (c) 2000 American Institute of Physics.

  6. Electric field detection of coherent synchrotron radiation in a storage ring generated using laser bunch slicing

    SciTech Connect

    Katayama, I.; Shimosato, H.; Bito, M.; Furusawa, K.; Adachi, M.; Zen, H.; Kimura, S.; Katoh, M.; Shimada, M.; Yamamoto, N.; Hosaka, M.; Ashida, M.

    2012-03-12

    The electric field of coherent synchrotron radiation (CSR) generated by laser bunch slicing in a storage ring has been detected by an electro-optic sampling method. The gate pulses for sampling are sent through a large-mode-area photonic-crystal fiber. The observed electric field profile of the CSR is in good agreement with the spectrum of the CSR observed using Fourier transform far-infrared spectrometry, indicating good phase stability in the CSR. The longitudinal density profiles of electrons modulated by laser pulses were evaluated from the electric field profile.

  7. An economic analysis of the electricity generation potential from biogas resources in the state of Indiana

    NASA Astrophysics Data System (ADS)

    Giraldo, Juan S.

    Anaerobic digestion is a process that is a common part of organic waste management systems and is used in concentrated animal feeding operations (CAFOs), wastewater treatment plants (WWTPs), and municipal solid waste (MSW) landfills. The process produces biogas, which contains methane, and it can be burned to generate electricity. Previous reports have indicated that based on the availability of feedstocks there is a large potential for biogas production and use for electricity generation in the state of Indiana. However, these reports varied in their consideration of important factors that affect the technical and economic feasibility of being able to develop the resources available. The goal of this thesis is to make a more targeted assessment of the electricity generation potential from biogas resources at CAFOs, WWTPs, and MSW landfills in Indiana. A capital budgeting model is used to estimate the net present value (NPV) of biogas electricity projects at facilities that are identified as technically suitable. A statewide estimate of the potential generation capacity is made by estimating the number of facilities that could profitably undertake a biogas electricity project. In addition this thesis explored the impact that different incentive policies would have on the economic viability of these projects. The results indicated that the electricity generation potential is much smaller when technical and economic factors are taken into account in addition to feedstock availability. In particular it was found that projects at hog farms are unlikely to be economically feasible in the present even when financial incentives are considered. In total, 47.94 MW of potential generating capacity is estimated from biogas production at CAFOs, WWTPs, and MSW landfills. Though results indicated that 37.10 MW of capacity are economically feasible under current operating conditions, sensitivity analysis reveals that these projects are very sensitive to capital cost assumptions

  8. Electricity generation from cattle manure slurry by cassette-electrode microbial fuel cells.

    PubMed

    Inoue, Kengo; Ito, Toshihiro; Kawano, Yoshihiro; Iguchi, Atsushi; Miyahara, Morio; Suzuki, Yoshihiro; Watanabe, Kazuya

    2013-11-01

    Cassette-electrode microbial fuel cells (CE-MFCs) are efficient and scalable devices for electricity production from organic waste. Previous studies have demonstrated that CE-MFCs are capable of generating electricity from artificial wastewater at relatively high efficiencies. In this study, a single-cassette CE-MFC was constructed, and its capacity for electricity generation from cattle manure suspended in water (solid to water ratio of 1:50) was examined. The CE-MFC reactor was operated in batch mode for 49 days; electricity generation became stable 2 weeks after initiating the operation. The maximum power density was measured at 16.3 W m⁻³ on day 26. Sequencing analysis of PCR-amplified 16S rRNA gene fragments obtained from the original manure and from anode biofilms suggested that Chloroflexi and Geobacteraceae were abundant in the anode biofilm (29% and 18%, respectively), whereas no Geobacteraceae sequences were detected in the original manure sample. The results of this study suggest that CE-MFCs can be used to generate electricity from water-suspended cattle manure in a scalable MFC system.

  9. Study of Electrical Conduction Mechanism of Organic Double-Layer Diode Using Electric Field Induced Optical Second Harmonic Generation Measurement.

    PubMed

    Nishi, Shohei; Taguchi, Dai; Manaka, Takaaki; Iwamoto, Mitsumasa

    2016-04-01

    By using electric field induced optical second harmonic generation (EFISHG) and current voltage (I-V) measurements, we studied the electrical transport mechanism of organic double-layer diodes with a structure of Au/N, N'-di-[(1-naphthyl)-N, N'-diphenyl]-(1,1'-biphenyl)-4,4'-diamine (a-NPD)/poly(methyl methacrylate) (PMMA)/indium zinc oxide (IZO). Here the α-NPD is a carrier transport layer and the PMMA is an electrical insulating layer. The current level was very low, but the I-V characteristics showed a rectifying behavior. The EFISHG measurement selectively and directly probed the electric field across the α-NPD layer, and showed that the electric field across the a-NPD layer is completely relaxed owing to the charge accumulation at the a-NPD/PMMA interface in the region V > 0, whereas the carrier accumulation was not significant in the region V < 0. On the basis of these experimental results, we proposed a model of the rectification. Further, by coupling the I-V characteristics with the EFISHG measurement, the I-V characteristics of the diodes were well converted into the current-electric field (I-E) characteristics of the α-NPD layer and the PMMA layer. The I-E characteristics suggested the Schottky-type conduction governs the carrier transport. We conclude that the I-V measurement coupled with the EFISHG measurement is very useful to study carrier transport mechanism of the organic double-layer diodes. PMID:27451633

  10. Marginal capacity costs of electricity distribution and demand for distributed generation

    SciTech Connect

    Woo, Chi-Keung, Lloyd-Zanetti, D.; Orans, R.

    1995-12-31

    Marginal costs of electricity vary by time and location. Past researchers attributed these variations to factors related to electricity generation, transmission and distribution. Past authors, however, did not fully analyze the large variations in marginal distribution capacity costs (MDCC) by area and time. Thus, the objectives of this paper are as follows: (1) to show that large MDCC variations exist within a utility`s service territory; (2) to demonstrate inter-utility variations in MDCC; and (3) to demonstrate the usefulness of these costs in determining demand for distributed generation (DG). 27 refs., 3 figs., 2 tabs.

  11. Electrical power systems (Dominican Republic). Generator sets, February 1991. Export trade information

    SciTech Connect

    Not Available

    1991-02-01

    The market for U.S. generators in the Dominican Republic from depressed 1991 levels and grow at a rate of 10% for the next three years. While the national power corporation has improved both supply and distribution of electricity, growth in manufacturing and tourism is expected to create more demand. Also, the dramatically reduced delivery of electricity by the power company in 1990-1991 caused such a strain on generators in place that much of the existing stock will need to be replaced. The U.S. with 54% of the total market dominates the large industrial market while Japan is most competitive with the small domestic use market.

  12. Evolution of Wholesale Electricity Market Design with Increasing Levels of Renewable Generation

    SciTech Connect

    Ela, E.; Milligan, M.; Bloom, A.; Botterud, A.; Townsend, A.; Levin, T.

    2014-09-01

    Variable generation such as wind and photovoltaic solar power has increased substantially in recent years. Variable generation has unique characteristics compared to the traditional technologies that supply energy in the wholesale electricity markets. These characteristics create unique challenges in planning and operating the power system, and they can also influence the performance and outcomes from electricity markets. This report focuses on two particular issues related to market design: revenue sufficiency for long-term reliability and incentivizing flexibility in short-term operations. The report provides an overview of current design and some designs that have been proposed by industry or researchers.

  13. Independent Orbiter Assessment (IOA): Analysis of the electrical power distribution and control/electrical power generation subsystem

    NASA Technical Reports Server (NTRS)

    Patton, Jeff A.

    1986-01-01

    The results of the Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis (FMEA) and Critical Items List (CIL) are presented. The IOA approach features a top-down analysis of the hardware to determine failure modes, criticality, and potential critical items. To preserve independence, this analysis was accomplished without reliance upon the results contained within the NASA FMEA/CIL documentation. This report documents the independent analysis results corresponding to the Orbiter Electrical Power Distribution and Control (EPD and C)/Electrical Power Generation (EPG) hardware. The EPD and C/EPG hardware is required for performing critical functions of cryogenic reactant storage, electrical power generation and product water distribution in the Orbiter. Specifically, the EPD and C/EPG hardware consists of the following components: Power Section Assembly (PSA); Reactant Control Subsystem (RCS); Thermal Control Subsystem (TCS); Water Removal Subsystem (WRS); and Power Reactant Storage and Distribution System (PRSDS). The IOA analysis process utilized available EPD and C/EPG hardware drawings and schematics for defining hardware assemblies, components, and hardware items. Each level of hardware was evaluated and analyzed for possible failure modes and effects. Criticality was assigned based upon the severity of the effect for each failure mode.

  14. Fully Electrical Modeling of Thermoelectric Generators with Contact Thermal Resistance Under Different Operating Conditions

    NASA Astrophysics Data System (ADS)

    Siouane, Saima; Jovanović, Slaviša; Poure, Philippe

    2016-09-01

    The Seebeck effect is used in thermoelectric generators (TEGs) to supply electronic circuits by converting the waste thermal into electrical energy. This generated electrical power is directly proportional to the temperature difference between the TEG module's hot and cold sides. Depending on the applications, TEGs can be used either under constant temperature gradient between heat reservoirs or constant heat flow conditions. Moreover, the generated electrical power of a TEG depends not only on these operating conditions, but also on the contact thermal resistance. The influence of the contact thermal resistance on the generated electrical power have already been extensively reported in the literature. However, as reported in Park et al. (Energy Convers Manag 86:233, 2014) and Montecucco and Knox (IEEE Trans Power Electron 30:828, 2015), while designing TEG-powered circuit and systems, a TEG module is mostly modeled with a Thévenin equivalent circuit whose resistance is constant and voltage proportional to the temperature gradient applied to the TEG's terminals. This widely used simplified electrical TEG model is inaccurate and not suitable under constant heat flow conditions or when the contact thermal resistance is considered. Moreover, it does not provide realistic behaviour corresponding to the physical phenomena taking place in a TEG. Therefore, from the circuit designer's point of view, faithful and fully electrical TEG models under different operating conditions are needed. Such models are mainly necessary to design and evaluate the power conditioning electronic stages and the maximum power point tracking algorithms of a TEG power supply. In this study, these fully electrical models with the contact thermal resistance taken into account are presented and the analytical expressions of the Thévenin equivalent circuit parameters are provided.

  15. Economic impact of non-utility generation on electric power systems

    NASA Astrophysics Data System (ADS)

    Gupta, Rajnish

    Non-Utility Generation is a major force in the way electrical energy is now being produced and marketed, and electric utilities are reacting to the growth of this new industry. When a utility buys electric energy from a non-utility generation at short notice, such as a few hours, one of the difficult issues encountered by the utility is the evaluation of the rate (buyback rate) it should pay the non-utility generation such that the utility maximizes its economic benefit. Utilities calculate their purchase rates based on a number of different formulae. Short term buyback rates should be based on the operating cost that a utility avoids by utilizing energy from a non-utility generation. This cost is termed as the avoided operating cost in this thesis. Suitable techniques for thermal and hydrothermal systems are developed to assess the short term avoided operating cost under different operating conditions. The studies described in this thesis focus specifically on the economic assessment of the incorporation of non-utility generation in the short term planning of power systems at the generation level and the composite generation and transmission level. In another study, it was assumed that non-utility generation produces energy from its cogeneration and wind facilities. These sources of energy have some typical characteristics that make them different from other sources of electricity. These characteristics were taken into account in modeling the non-utility generation and studies were performed to show their effect on a thermal power system. Composite generation and transmission assessment involves a composite appraisal of both the generation and transmission facilities and their ability to supply adequate, dependable and suitable electrical energy to the major load point. Studies were performed to show the impact of non-utility generation on a thermal power system at this level. The studies and examples presented in the thesis suggest that the proposed techniques

  16. Analysis of geothermal electric-power generation at Big Creek Hot Springs, Lemhi County, Idaho

    SciTech Connect

    Struhsacker, D.W.

    1981-01-01

    Big Creek Hot Springs was evaluated as a source of electrical power for the Blackbird Cobalt Mine, approximately 13 miles south of the hot spring. An evaluaton of the geothermal potential of Big Creek Hot Springs, a suggested exploration program and budget, an engineering feasibility study of power generation at Big Creek Hot Springs, an economic analysis of the modeled power generating system, and an appraisal of the institutional factors influencing development at Big Creek Hot Springs are included.

  17. Generator Bidding Strategies in a Competitive Electricity Market with Derating and Bid-Segment Considerations

    SciTech Connect

    Lu, Ning; Chow, Joe H.; Desrochers, Alan A.

    2009-07-31

    This paper develops optimal generator bidding strategies in a competitive electricity market. Starting from a generator’s cost curve, basic bidding concepts such as the break-even bid curve and the maximum profit bid curve can be readily derived. The maximum profit bid curve can be extended to account for generator availability and derating. In addition, multiple-segment block energy bids can be optimized based on the maximum profit curve and the probabilistic distribution of market clearing prices.

  18. Effects of overnight fasting on working memory-related brain network: an fMRI study.

    PubMed

    Chechko, Natalia; Vocke, Sebastian; Habel, Ute; Toygar, Timur; Kuckartz, Lisa; Berthold-Losleben, Mark; Laoutidis, Zacharias G; Orfanos, Stelios; Wassenberg, Annette; Karges, Wölfram; Schneider, Frank; Kohn, Nils

    2015-03-01

    Glucose metabolism serves as the central source of energy for the human brain. Little is known about the effects of blood glucose level (BGL) on higher-order cognitive functions within a physiological range (e.g., after overnight fasting). In this randomized, placebo-controlled, double blind study, we assessed the impact of overnight fasting (14 h) on brain activation during a working memory task. We sought to mimic BGLs that occur naturally in healthy humans after overnight fasting. After standardized periods of food restriction, 40 (20 male) healthy participants were randomly assigned to receive either glucagon to balance the BGL or placebo (NaCl). A parametric fMRI paradigm, including 2-back and 0-back tasks, was used. Subclinically low BGL following overnight fasting was found to be linked to reduced involvement of the bilateral dorsal midline thalamus and the bilateral basal ganglia, suggesting high sensitivity of those regions to minimal changes in BGLs. Our results indicate that overnight fasting leads to physiologically low levels of glucose, impacting brain activation during working memory tasks even when there are no differences in cognitive performance.

  19. Effects of overnight fasting on working memory-related brain network: an fMRI study.

    PubMed

    Chechko, Natalia; Vocke, Sebastian; Habel, Ute; Toygar, Timur; Kuckartz, Lisa; Berthold-Losleben, Mark; Laoutidis, Zacharias G; Orfanos, Stelios; Wassenberg, Annette; Karges, Wölfram; Schneider, Frank; Kohn, Nils

    2015-03-01

    Glucose metabolism serves as the central source of energy for the human brain. Little is known about the effects of blood glucose level (BGL) on higher-order cognitive functions within a physiological range (e.g., after overnight fasting). In this randomized, placebo-controlled, double blind study, we assessed the impact of overnight fasting (14 h) on brain activation during a working memory task. We sought to mimic BGLs that occur naturally in healthy humans after overnight fasting. After standardized periods of food restriction, 40 (20 male) healthy participants were randomly assigned to receive either glucagon to balance the BGL or placebo (NaCl). A parametric fMRI paradigm, including 2-back and 0-back tasks, was used. Subclinically low BGL following overnight fasting was found to be linked to reduced involvement of the bilateral dorsal midline thalamus and the bilateral basal ganglia, suggesting high sensitivity of those regions to minimal changes in BGLs. Our results indicate that overnight fasting leads to physiologically low levels of glucose, impacting brain activation during working memory tasks even when there are no differences in cognitive performance. PMID:25393934

  20. Electricity generation directly using human feces wastewater for life support system

    NASA Astrophysics Data System (ADS)

    Fangzhou, Du; Zhenglong, Li; Shaoqiang, Yang; Beizhen, Xie; Hong, Liu

    2011-05-01

    Wastewater reuse and power regeneration are key issues in the research of bioregeneration life support system (BLSS). Microbial fuel cell (MFC) can generate electricity during the process of wastewater treatment, which might be promising to solve the two problems simultaneously. We used human feces wastewater containing abundant organic compounds as the substrate of MFC to generate electricity, and the factors concerning electricity generation capacity were investigated. The removal efficiency of total chemical oxygen demand (TCOD), Soluble chemical oxygen demand (SCOD) and NH4+ reached 71%, 88% and 44%, respectively with two-chamber MFC when it was fed with the actual human feces wastewater and operated for 190 h. And the maximum power density reached 70.8 mW/m 2, which implicated that MFC technology was feasible and appropriate for treating human feces wastewater. In order to improve the power generation of MFC further, human feces wastewater were fermented before poured into MFC, and the result showed that fermentation pretreatment could improve the MFC output obviously. The maximum power density of MFC fed with pretreated human feces wastewater was 22 mW/m 2, which was 47% higher than that of the control without pretreatment (15 mW/m 2). Furthermore, the structure of MFC was studied and it was found that both enlarging the area of electrodes and shortening the distance between electrodes could increase the electricity generation capacity. Finally, an automatic system, controlled by time switches and electromagnetic valves, was established to process one person's feces wastewater (1 L/d) while generating electricity. The main parts of this system comprised a pretreatment device and 3 one-chamber air-cathode MFCs. The total power could reach 787.1 mW and power density could reach the maximum of about 240 mW/m 2.

  1. A generative modeling approach to connectivity-Electrical conduction in vascular networks.

    PubMed

    Hald, Bjørn Olav

    2016-06-21

    The physiology of biological structures is inherently dynamic and emerges from the interaction and assembly of large collections of small entities. The extent of coupled entities complicates modeling and increases computational load. Here, microvascular networks are used to present a novel generative approach to connectivity based on the observation that biological organization is hierarchical and composed of a limited set of building blocks, i.e. a vascular network consists of blood vessels which in turn are composed by one or more cell types. Fast electrical communication is crucial to synchronize vessel tone across the vast distances within a network. We hypothesize that electrical conduction capacity is delimited by the size of vascular structures and connectivity of the network. Generation and simulation of series of dynamical models of electrical spread within vascular networks of different size and composition showed that (1) Conduction is enhanced in models harboring long and thin endothelial cells that couple preferentially along the longitudinal axis. (2) Conduction across a branch point depends on endothelial connectivity between branches. (3) Low connectivity sub-networks are more sensitive to electrical perturbations. In summary, the capacity for electrical signaling in microvascular networks is strongly shaped by the morphology and connectivity of vascular (particularly endothelial) cells. While the presented software can be used by itself or as a starting point for more sophisticated models of vascular dynamics, the generative approach can be applied to other biological systems, e.g. nervous tissue, the lymphatics, or the biliary system.

  2. Contribution of Anaerobic Digesters to Emissions Mitigation and Electricity Generation Under U.S. Climate Policy

    PubMed Central

    2011-01-01

    Livestock husbandry in the U.S. significantly contributes to many environmental problems, including the release of methane, a potent greenhouse gas (GHG). Anaerobic digesters (ADs) break down organic wastes using bacteria that produce methane, which can be collected and combusted to generate electricity. ADs also reduce odors and pathogens that are common with manure storage and the digested manure can be used as a fertilizer. There are relatively few ADs in the U.S., mainly due to their high capital costs. We use the MIT Emissions Prediction and Policy Analysis (EPPA) model to test the effects of a representative U.S. climate stabilization policy on the adoption of ADs which sell electricity and generate methane mitigation credits. Under such policy, ADs become competitive at producing electricity in 2025, when they receive methane reduction credits and electricity from fossil fuels becomes more expensive. We find that ADs have the potential to generate 5.5% of U.S. electricity. PMID:21761880

  3. Contribution of anaerobic digesters to emissions mitigation and electricity generation under U.S. climate policy.

    PubMed

    Zaks, David P M; Winchester, Niven; Kucharik, Christopher J; Barford, Carol C; Paltsev, Sergey; Reilly, John M

    2011-08-15

    Livestock husbandry in the U.S. significantly contributes to many environmental problems, including the release of methane, a potent greenhouse gas (GHG). Anaerobic digesters (ADs) break down organic wastes using bacteria that produce methane, which can be collected and combusted to generate electricity. ADs also reduce odors and pathogens that are common with manure storage and the digested manure can be used as a fertilizer. There are relatively few ADs in the U.S., mainly due to their high capital costs. We use the MIT Emissions Prediction and Policy Analysis (EPPA) model to test the effects of a representative U.S. climate stabilization policy on the adoption of ADs which sell electricity and generate methane mitigation credits. Under such policy, ADs become competitive at producing electricity in 2025, when they receive methane reduction credits and electricity from fossil fuels becomes more expensive. We find that ADs have the potential to generate 5.5% of U.S. electricity. PMID:21761880

  4. Characterization of acoustic shockwaves generated by exposure to nanosecond electrical pulses

    NASA Astrophysics Data System (ADS)

    Roth, Caleb C.; Maswadi, Saher; Ibey, Bennett L.; Beier, Hope T.; Glickman, Randolph D.

    2014-03-01

    Despite 30 years of research, the mechanism behind the induced breakdown of plasma membranes by electrical pulses, termed electroporation, remains unknown. Current theories treat the interaction between the electrical field and the membrane as an entirely electrical event pointing to multiple plausible mechanisms. By investigating the biophysical interaction between plasma membranes and nanosecond electrical pulses (nsEP), we may have identified a non-electric field driven mechanism, previously unstudied in nsEP, which could be responsible for nanoporation of plasma membranes. In this investigation, we use a non-contact optical technique, termed probe beam deflection technique (PBDT), to characterize acoustic shockwaves generated by nsEP traveling through tungsten wire electrodes. We conclude these acoustic shockwaves are the result of the nsEP exposure imparting electrohydraulic forces on the buffer solution. When these acoustic shockwaves occur in close proximity to lipid bilayer membranes, it is possible that they impart a sufficient amount of mechanical stress to cause poration of that membrane. This research establishes for the first time that nsEP discharged in an aqueous medium generate measureable pressure waves of a magnitude capable of mechanical deformation and possibly damage to plasma membranes. These findings provide a new insight into the longunanswered question of how electric fields cause the breakdown of plasma membranes.

  5. A model for estimation of potential generation of waste electrical and electronic equipment in Brazil.

    PubMed

    Araújo, Marcelo Guimarães; Magrini, Alessandra; Mahler, Cláudio Fernando; Bilitewski, Bernd

    2012-02-01

    Sales of electrical and electronic equipment are increasing dramatically in developing countries. Usually, there are no reliable data about quantities of the waste generated. A new law for solid waste management was enacted in Brazil in 2010, and the infrastructure to treat this waste must be planned, considering the volumes of the different types of electrical and electronic equipment generated. This paper reviews the literature regarding estimation of waste electrical and electronic equipment (WEEE), focusing on developing countries, particularly in Latin America. It briefly describes the current WEEE system in Brazil and presents an updated estimate of generation of WEEE. Considering the limited available data in Brazil, a model for WEEE generation estimation is proposed in which different methods are used for mature and non-mature market products. The results showed that the most important variable is the equipment lifetime, which requires a thorough understanding of consumer behavior to estimate. Since Brazil is a rapidly expanding market, the "boom" in waste generation is still to come. In the near future, better data will provide more reliable estimation of waste generation and a clearer interpretation of the lifetime variable throughout the years.

  6. A model for estimation of potential generation of waste electrical and electronic equipment in Brazil

    SciTech Connect

    Araujo, Marcelo Guimaraes; Magrini, Alessandra; Mahler, Claudio Fernando; Bilitewski, Bernd

    2012-02-15

    Highlights: Black-Right-Pointing-Pointer Literature of WEEE generation in developing countries is reviewed. Black-Right-Pointing-Pointer We analyse existing estimates of WEEE generation for Brazil. Black-Right-Pointing-Pointer We present a model for WEEE generation estimate. Black-Right-Pointing-Pointer WEEE generation of 3.77 kg/capita year for 2008 is estimated. Black-Right-Pointing-Pointer Use of constant lifetime should be avoided for non-mature market products. - Abstract: Sales of electrical and electronic equipment are increasing dramatically in developing countries. Usually, there are no reliable data about quantities of the waste generated. A new law for solid waste management was enacted in Brazil in 2010, and the infrastructure to treat this waste must be planned, considering the volumes of the different types of electrical and electronic equipment generated. This paper reviews the literature regarding estimation of waste electrical and electronic equipment (WEEE), focusing on developing countries, particularly in Latin America. It briefly describes the current WEEE system in Brazil and presents an updated estimate of generation of WEEE. Considering the limited available data in Brazil, a model for WEEE generation estimation is proposed in which different methods are used for mature and non-mature market products. The results showed that the most important variable is the equipment lifetime, which requires a thorough understanding of consumer behavior to estimate. Since Brazil is a rapidly expanding market, the 'boom' in waste generation is still to come. In the near future, better data will provide more reliable estimation of waste generation and a clearer interpretation of the lifetime variable throughout the years.

  7. Dynamics and control of Stirling engines in a 15 kWe solar electric generation concept

    NASA Technical Reports Server (NTRS)

    Das, R. L.; Bahrami, K. A.

    1979-01-01

    This paper discusses the application of kinematic and free piston Stirling engines in a 15 kWe dish-electric approach for solar thermal electric generation. Initially, the principle of operation of Stirling engines in solar thermal electric generation is discussed. Then, under certain simplifying assumptions, mathematical models describing the dynamic operation of the kinematic and free piston Stirling engines are developed. It is found that the engine dynamics may be approximated by second order models. Control mechanisms for both types of Stirling engines are discussed. An approach based on the modulation of the working fluid mean pressure is presented. It is concluded that this approach offers a fast and effective means of control. The free piston Stirling engine, being a thermally driven mechanical oscillator, presents unique control requirements. These are discussed in this paper.

  8. Power System Modeling of 20percent Wind-Generated Electricity by 2030

    SciTech Connect

    Bolinger, Mark A; Hand, Maureen; Blair, Nate; Bolinger, Mark; Wiser, Ryan; Hern, Tracy; Miller, Bart; O'Connell, R.

    2008-06-09

    The Wind Energy Deployment System model was used to estimate the costs and benefits associated with producing 20% of the nation's electricity from wind technology by 2030. This generation capacity expansion model selects from electricity generation technologies that include pulverized coal plants, combined cycle natural gas plants, combustion turbine natural gas plants, nuclear plants, and wind technology to meet projected demand in future years. Technology cost and performance projections, as well as transmission operation and expansion costs, are assumed. This study demonstrates that producing 20% of the nation's projected electricity demand in 2030 from wind technology is technically feasible, not cost-prohibitive, and provides benefits in the forms of carbon emission reductions, natural gas price reductions, and water savings.

  9. Experimental investigation of a variable speed constant frequency electric generating system from a utility perspective

    NASA Technical Reports Server (NTRS)

    Herrera, J. I.; Reddoch, T. W.; Lawler, J. S.

    1985-01-01

    As efforts are accelerated to improve the overall capability and performance of wind electric systems, increased attention to variable speed configurations has developed. A number of potentially viable configurations have emerged. Various attributes of variable speed systems need to be carefully tested to evaluate their performance from the utility points of view. With this purpose, the NASA experimental variable speed constant frequency (VSCF) system has been tested. In order to determine the usefulness of these systems in utility applications, tests are required to resolve issues fundamental to electric utility systems. Legitimate questions exist regarding how variable speed generators will influence the performance of electric utility systems; therefore, tests from a utility perspective, have been performed on the VSCF system and an induction generator at an operating power level of 30 kW on a system rated at 200 kVA and 0.8 power factor.

  10. Experimental investigation of a variable speed constant frequency electric generating system from a utility perspective

    NASA Astrophysics Data System (ADS)

    Herrera, J. I.; Reddoch, T. W.; Lawler, J. S.

    1985-05-01

    As efforts are accelerated to improve the overall capability and performance of wind electric systems, increased attention to variable speed configurations has developed. A number of potentially viable configurations have emerged. Various attributes of variable speed systems need to be carefully tested to evaluate their performance from the utility points of view. With this purpose, the NASA experimental variable speed constant frequency (VSCF) system has been tested. In order to determine the usefulness of these systems in utility applications, tests are required to resolve issues fundamental to electric utility systems. Legitimate questions exist regarding how variable speed generators will influence the performance of electric utility systems; therefore, tests from a utility perspective, have been performed on the VSCF system and an induction generator at an operating power level of 30 kW on a system rated at 200 kVA and 0.8 power factor.

  11. Electric-field dependence of photocarrier generation efficiency of organic photoconductors

    SciTech Connect

    Umeda, Minoru

    2015-03-07

    The electric-field dependence of photocarrier generation efficiency has been investigated in several different types of organic photoconductor for electrophotography to elucidate the controlling factors of light-to-electrical energy conversion. The rate-determining step in generating photocarriers has been considered to be the charge transfer between two neighboring molecules. Overall photocarrier generation efficiency has been determined using the charge transfer velocity at the rate-determining step as a function of electric-field-dependent activation energy, which is influenced by the symmetry factor α and the energy gap ΔE. The formula used successfully fits the experimental data for different types of organic photoconductor over a wide field strengths range. From the fitting results of high-sensitivity photoconductors, the zero-field activation energy is small and the reactant lifetime is long. In addition, ΔE is zero, which implies that the hole-electron interaction in the reactant is negligible at the rate-determining step. In contrast, for low-sensitivity photoconductors, the zero-field activation energy is large and the reactant lifetime is short; however, ΔE < 0 and α > 0.5, which suggest that the hole-electron interaction is not negligible. Consequently, the proposed formula well explains the electric-field dependence of photocarrier generation efficiency on the basis of its controlling factors.

  12. Investigation on magnetoacoustic signal generation with magnetic induction and its application to electrical conductivity reconstruction.

    PubMed

    Ma, Qingyu; He, Bin

    2007-08-21

    A theoretical study on the magnetoacoustic signal generation with magnetic induction and its applications to electrical conductivity reconstruction is conducted. An object with a concentric cylindrical geometry is located in a static magnetic field and a pulsed magnetic field. Driven by Lorentz force generated by the static magnetic field, the magnetically induced eddy current produces acoustic vibration and the propagated sound wave is received by a transducer around the object to reconstruct the corresponding electrical conductivity distribution of the object. A theory on the magnetoacoustic waveform generation for a circular symmetric model is provided as a forward problem. The explicit formulae and quantitative algorithm for the electrical conductivity reconstruction are then presented as an inverse problem. Computer simulations were conducted to test the proposed theory and assess the performance of the inverse algorithms for a multi-layer cylindrical model. The present simulation results confirm the validity of the proposed theory and suggest the feasibility of reconstructing electrical conductivity distribution based on the proposed theory on the magnetoacoustic signal generation with magnetic induction.

  13. Electricity-producing heating apparatus utilizing a turbine generator in a semi-closed brayton cycle

    DOEpatents

    Labinov, Solomon D.; Christian, Jeffrey E.

    2003-10-07

    The present invention provides apparatus and methods for producing both heat and electrical energy by burning fuels in a stove or boiler using a novel arrangement of a surface heat exchanger and microturbine-powered generator and novel surface heat exchanger. The equipment is particularly suited for use in rural and relatively undeveloped areas, especially in cold regions and highlands.

  14. RELATIONSHIPS BETWEEN NITROGEN OXIDE EMISSIONS FROM ELECTRICAL GENERATING UNITS IN THE U.S. AND METEOROLOGY

    EPA Science Inventory

    Nitrogen oxide (NOx) emissions from electrical generating units (EGUs) in the northeast US have declined dramatically during the past few years as a result of a series of air quality rules (RACT rule, Clean Air Act Amendments Title IV, and the NOx SIP call)....

  15. [Negative air ions generated by plants upon pulsed electric field stimulation applied to soil].

    PubMed

    Wu, Ren-ye; Deng, Chuan-yuan; Yang, Zhi-jian; Weng, Hai-yong; Zhu, Tie-jun-rong; Zheng, Jin-gui

    2015-02-01

    This paper investigated the capacity of plants (Schlumbergera truncata, Aloe vera var. chinensis, Chlorophytum comosum, Schlumbergera bridgesii, Gymnocalycium mihanovichii var. friedrichii, Aspidistra elatior, Cymbidium kanran, Echinocactus grusonii, Agave americana var. marginata, Asparagus setaceus) to generate negative air ions (NAI) under pulsed electric field stimulation. The results showed that single plant generated low amounts of NAI in natural condition. The capacity of C. comosum and G. mihanovichii var. friedrichii generated most NAI among the above ten species, with a daily average of 43 ion · cm(-3). The least one was A. americana var. marginata with the value of 19 ion · cm(-3). When proper pulsed electric field stimulation was applied to soil, the NAI of ten plant species were greatly improved. The effect of pulsed electric field u3 (average voltage over the pulse period was 2.0 x 10(4) V, pulse frequency was 1 Hz, and pulse duration was 50 ms) was the greatest. The mean NAI concentration of C. kanran was the highest 1454967 ion · cm(-3), which was 48498.9 times as much as that in natural condition. The lowest one was S. truncata with the value of 34567 ion · cm(-3), which was 843.1 times as much as that in natural condition. The capacity of the same plants to generate negative air ion varied extremely under different intensity pulsed electric fields. PMID:26094455

  16. Method and apparatus for improving the performance of a nuclear power electrical generation system

    DOEpatents

    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.

  17. Method and apparatus for steam mixing a nuclear fueled electricity generation system

    DOEpatents

    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.

  18. Student-Generated Assignments about Electrical Circuits in a Computer Simulation

    ERIC Educational Resources Information Center

    Vreman-de Olde, Cornelise; de Jong, Ton

    2004-01-01

    In this study we investigated the design of assignments by students as a knowledge-generating activity. Students were required to design assignments for 'other students' in a computer simulation environment about electrical circuits. Assignments consisted of a question, alternatives, and feedback on those alternatives. In this way, subjects were…

  19. Electricity Generation and Wastewater Treatment of Oil Refinery in Microbial Fuel Cells Using Pseudomonas putida

    PubMed Central

    Majumder, Dip; Maity, Jyoti Prakash; Tseng, Min-Jen; Nimje, Vanita Roshan; Chen, Hau-Ren; Chen, Chien-Cheng; Chang, Young-Fo; Yang, Tsui-Chu; Chen, Chen-Yen

    2014-01-01

    Microbial fuel cells (MFCs) represent a novel platform for treating wastewater and at the same time generating electricity. Using Pseudomonas putida (BCRC 1059), a wild-type bacterium, we demonstrated that the refinery wastewater could be treated and also generate electric current in an air-cathode chamber over four-batch cycles for 63 cumulative days. Our study indicated that the oil refinery wastewater containing 2213 mg/L (ppm) chemical oxygen demand (COD) could be used as a substrate for electricity generation in the reactor of the MFC. A maximum voltage of 355 mV was obtained with the highest power density of 0.005 mW/cm2 in the third cycle with a maximum current density of 0.015 mA/cm2 in regard to the external resistor of 1000 Ω. A maximum coulombic efficiency of 6 × 10−2% was obtained in the fourth cycle. The removal efficiency of the COD reached 30% as a function of time. Electron transfer mechanism was studied using cyclic voltammetry, which indicated the presence of a soluble electron shuttle in the reactor. Our study demonstrated that oil refinery wastewater could be used as a substrate for electricity generation. PMID:25247576

  20. A Review of Operational Water Consumption and Withdrawal Factors for Electricity Generating Technologies

    SciTech Connect

    Macknick, Jordan; Newmark, Robin; Heath, Garvin; Hallett, K. C.

    2011-03-01

    This report provides estimates of operational water withdrawal and water consumption factors for electricity generating technologies in the United States. Estimates of water factors were collected from published primary literature and were not modified except for unit conversions. The presented water factors may be useful in modeling and policy analyses where reliable power plant level data are not available.

  1. Electricity generation and wastewater treatment of oil refinery in microbial fuel cells using Pseudomonas putida.

    PubMed

    Majumder, Dip; Maity, Jyoti Prakash; Tseng, Min-Jen; Nimje, Vanita Roshan; Chen, Hau-Ren; Chen, Chien-Cheng; Chang, Young-Fo; Yang, Tsui-Chu; Chen, Chen-Yen

    2014-09-22

    Microbial fuel cells (MFCs) represent a novel platform for treating wastewater and at the same time generating electricity. Using Pseudomonas putida (BCRC 1059), a wild-type bacterium, we demonstrated that the refinery wastewater could be treated and also generate electric current in an air-cathode chamber over four-batch cycles for 63 cumulative days. Our study indicated that the oil refinery wastewater containing 2213 mg/L (ppm) chemical oxygen demand (COD) could be used as a substrate for electricity generation in the reactor of the MFC. A maximum voltage of 355 mV was obtained with the highest power density of 0.005 mW/cm² in the third cycle with a maximum current density of 0.015 mA/cm² in regard to the external resistor of 1000 Ω. A maximum coulombic efficiency of 6 × 10⁻²% was obtained in the fourth cycle. The removal efficiency of the COD reached 30% as a function of time. Electron transfer mechanism was studied using cyclic voltammetry, which indicated the presence of a soluble electron shuttle in the reactor. Our study demonstrated that oil refinery wastewater could be used as a substrate for electricity generation.

  2. Evaluation of conventional electric power generating industry quality assurance and reliability practices

    SciTech Connect

    Anderson, R.T.; Lauffenburger, H.A.

    1981-03-01

    The techniques and practices utilized in an allied industry (electric power generation) that might serve as a baseline for formulating Quality Assurance and Reliability (QA and R) procedures for photovoltaic solar energy systems were studied. The study results provide direct near-term input for establishing validation methods as part of the SERI performance criteria and test standards development task.

  3. Carbon Dioxide Emissions from the Generation of Electric Power in the United States 1998

    EIA Publications

    1999-01-01

    The President issued a directive on April 15, 1999, requiring an annual report summarizing carbon dioxide (CO2) emissions produced by electricity generation in the United States, including both utilities and nonutilities. In response, this report is jointly submitted by the U.S. Department of Energy and the U.S. Environmental Protection Agency.

  4. Electricity generation and wastewater treatment of oil refinery in microbial fuel cells using Pseudomonas putida.

    PubMed

    Majumder, Dip; Maity, Jyoti Prakash; Tseng, Min-Jen; Nimje, Vanita Roshan; Chen, Hau-Ren; Chen, Chien-Cheng; Chang, Young-Fo; Yang, Tsui-Chu; Chen, Chen-Yen

    2014-01-01

    Microbial fuel cells (MFCs) represent a novel platform for treating wastewater and at the same time generating electricity. Using Pseudomonas putida (BCRC 1059), a wild-type bacterium, we demonstrated that the refinery wastewater could be treated and also generate electric current in an air-cathode chamber over four-batch cycles for 63 cumulative days. Our study indicated that the oil refinery wastewater containing 2213 mg/L (ppm) chemical oxygen demand (COD) could be used as a substrate for electricity generation in the reactor of the MFC. A maximum voltage of 355 mV was obtained with the highest power density of 0.005 mW/cm² in the third cycle with a maximum current density of 0.015 mA/cm² in regard to the external resistor of 1000 Ω. A maximum coulombic efficiency of 6 × 10⁻²% was obtained in the fourth cycle. The removal efficiency of the COD reached 30% as a function of time. Electron transfer mechanism was studied using cyclic voltammetry, which indicated the presence of a soluble electron shuttle in the reactor. Our study demonstrated that oil refinery wastewater could be used as a substrate for electricity generation. PMID:25247576

  5. ETR ELECTRICAL BUILDING, TRA648. EMERGENCY STANDBY GENERATOR AND DIESEL UNIT. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    ETR ELECTRICAL BUILDING, TRA-648. EMERGENCY STANDBY GENERATOR AND DIESEL UNIT. METAL ROOF AND PUMICE BLOCK WALLS. CAMERA FACING SOUTHWEST. INL NEGATIVE NO. 56-3708. R.G. Larsen, Photographer, 11/13/1956 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

  6. Utilizing the green alga Chlamydomonas reinhardtii for microbial electricity generation: a living solar cell.

    PubMed

    Rosenbaum, Miriam; Schröder, Uwe; Scholz, Fritz

    2005-10-01

    By employing living cells of the green alga Chlamydomonas reinhardtii, we demonstrate the possibility of direct electricity generation from microbial photosynthetic activity. The presented concept is based on an in situ oxidative depletion of hydrogen, photosynthetically produced by C. reinhardtii under sulfur-deprived conditions, by polymer-coated electrocatalytic electrodes. PMID:15696280

  7. Pulse power generated electric fields as a means to control zebra mussels

    SciTech Connect

    Smythe, A.G.; Lange, C.L.; Doyle, J.F.

    1995-06-01

    In 1994, a study was conducted to determine if pulsed electric fields could reduce zebra mussel settlement rates. The study was a continuation of a study that began in 1991. Several types of fields were generated over the four-year study. The 1994 study concluded that fast rise DC, pulse power signals could stun post-veligers and significantly reduce settlement.

  8. The Environmental Impact of Electrical Power Generation: Nuclear and Fossil. Teacher's Guide.

    ERIC Educational Resources Information Center

    Pennsylvania State Dept. of Education, Harrisburg.

    This teacher's guide accompanies a course concerning the need, environmental costs, and benefits of electrical power generation. Each chapter of this guide corresponds to a chapter in the course text, and includes the following: a list of behavioral objectives for the corresponding chapter, a list of suggested activities, recommended audio-visual…

  9. Implications of Lower Natural Gas Prices for Electric Generators in the Southeast, The

    EIA Publications

    2009-01-01

    This supplement to the Energy Information Administration's (EIA) May 2009 Short-Term Energy Outlook (STEO) focuses on changes in the utilization of coal- and natural-gas-fired generation capacity in the electric utility sector as the differential between delivered fuel prices narrows.

  10. [Negative air ions generated by plants upon pulsed electric field stimulation applied to soil].

    PubMed

    Wu, Ren-ye; Deng, Chuan-yuan; Yang, Zhi-jian; Weng, Hai-yong; Zhu, Tie-jun-rong; Zheng, Jin-gui

    2015-02-01

    This paper investigated the capacity of plants (Schlumbergera truncata, Aloe vera var. chinensis, Chlorophytum comosum, Schlumbergera bridgesii, Gymnocalycium mihanovichii var. friedrichii, Aspidistra elatior, Cymbidium kanran, Echinocactus grusonii, Agave americana var. marginata, Asparagus setaceus) to generate negative air ions (NAI) under pulsed electric field stimulation. The results showed that single plant generated low amounts of NAI in natural condition. The capacity of C. comosum and G. mihanovichii var. friedrichii generated most NAI among the above ten species, with a daily average of 43 ion · cm(-3). The least one was A. americana var. marginata with the value of 19 ion · cm(-3). When proper pulsed electric field stimulation was applied to soil, the NAI of ten plant species were greatly improved. The effect of pulsed electric field u3 (average voltage over the pulse period was 2.0 x 10(4) V, pulse frequency was 1 Hz, and pulse duration was 50 ms) was the greatest. The mean NAI concentration of C. kanran was the highest 1454967 ion · cm(-3), which was 48498.9 times as much as that in natural condition. The lowest one was S. truncata with the value of 34567 ion · cm(-3), which was 843.1 times as much as that in natural condition. The capacity of the same plants to generate negative air ion varied extremely under different intensity pulsed electric fields.

  11. Fe(III) oxides accelerate microbial nitrate reduction and electricity generation by Klebsiella pneumoniae L17.

    PubMed

    Liu, Tongxu; Li, Xiaomin; Zhang, Wei; Hu, Min; Li, Fangbai

    2014-06-01

    Klebsiella pneumoniae L17 is a fermentative bacterium that can reduce iron oxide and generate electricity under anoxic conditions, as previously reported. This study reveals that K. pneumoniae L17 is also capable of dissimilatory nitrate reduction, producing NO2(-), NH4(+), NO and N2O under anoxic conditions. The presence of Fe(III) oxides (i.e., α-FeOOH, γ-FeOOH, α-Fe2O3 and γ-Fe2O3) significantly accelerates the reduction of nitrate and generation of electricity by K. pneumoniae L17, which is similar to a previous report regarding another fermentative bacterium, Bacillus. No significant nitrate reduction was observed upon treatment with Fe(2+) or α-FeOOH+Fe(2+), but a slight facilitation of nitrate reduction and electricity generation was observed upon treatment with L17+Fe(2+). This result suggests that aqueous Fe(II) or mineral-adsorbed Fe(II) cannot reduce nitrate abiotically but that L17 can catalyze the reduction of nitrate and generation of electricity in the presence of Fe(II) (which might exist as cell surface-bound Fe(II)). To rule out the potential effect of Fe(II) produced by L17 during microbial iron reduction, treatments with the addition of TiO2 or Al2O3 instead of Fe(III) oxides also exhibited accelerated microbial nitrate reduction and electricity generation, indicating that cell-mineral sorption did account for the acceleration effect. However, the acceleration caused by Fe(III) oxides is only partially attributed to the cell surface-bound Fe(II) and cell-mineral sorption but may be driven by the iron oxide conduction band-mediated electron transfer from L17 to nitrate or an electrode, as proposed previously. The current study extends the diversity of bacteria of which nitrate reduction and electricity generation can be facilitated by the presence of iron oxides and confirms the positive role of Fe(III) oxides on microbial nitrate reduction and electricity generation by particular fermentative bacteria in anoxic environments.

  12. Second generation ethanol in Brazil: can it compete with electricity production?

    PubMed

    Dias, Marina O S; Cunha, Marcelo P; Jesus, Charles D F; Rocha, George J M; Pradella, José Geraldo C; Rossell, Carlos E V; Filho, Rubens Maciel; Bonomi, Antonio

    2011-10-01

    Much of the controversy surrounding second generation ethanol production arises from the assumed competition with first generation ethanol production; however, in Brazil, where bioethanol is produced from sugarcane, sugarcane bagasse and trash will be used as feedstock for second generation ethanol production. Thus, second generation ethanol production may be primarily in competition with electricity production from the lignocellulosic fraction of sugarcane. A preliminary technical and economic analysis of the integrated production of first and second generation ethanol from sugarcane in Brazil is presented and different technological scenarios are evaluated. The analysis showed the importance of the integrated use of sugarcane including the biomass represented by surplus bagasse and trash that can be taken from the field. Second generation ethanol may favorably compete with bioelectricity production when sugarcane trash is used and when low cost enzyme and improved technologies become commercially available. PMID:21795041

  13. Generating Electric Power in the Pacific Northwest. Implications of Alternative Technologies

    NASA Astrophysics Data System (ADS)

    Pernin, Christopher G.; Bernstein, Mark A.; Mejia, Andrea; Shih, Howard; Rueter, Fred

    2002-01-01

    The Pacific Northwest faces some critical energy issues over the next 20 years. There is significant uncertainty about energy supplies, energy prices, and the implications of competitive energy markets. Therefore, as energy demands continue to rise, it is important for the states in the region to understand the risks and opportunities of different energy supply and demand options. This report addresses issues in electricity supply and demand for four states in the Pacific Northwest: Idaho, Montana, Oregon, and Washington. For much of the past 50 years, these states have relied heavily on hydroelectric power to meet their energy needs, and this inexpensive electricity has helped keep electricity rates low in the region, compared with the rest of the United States. However, the region cannot add much new hydroelectric capacity, so increasing demands for electricity in the future will have to be met by other sources. It is expected that the bulk of new electricity-generating capacity will come from natural-gas-fired power plants. While the combined share of electricity generated by hydroelectric and natural-gas-fired plants is expected to remain the same through 2010 (together, they provide 86 percent of the capacity in the region, the remainder being provided primarily by coal and nuclear plants), the proportion generated by natural gas will rise dramatically. Table S.1 summarizes the shares of current and future expected generating capacity in the region. The changes in the shares provided by the two major sources will have a number of consequences for the states in the region.

  14. Generation of electric fields and currents by neutral flows in weakly ionized plasmas through collisional dynamos

    NASA Astrophysics Data System (ADS)

    Dimant, Y. S.; Oppenheim, M. M.; Fletcher, A. C.

    2016-08-01

    In weakly ionized plasmas neutral flows drag plasma across magnetic field lines generating intense electric fields and currents. An example occurs in the Earth's ionosphere near the geomagnetic equator. Similar processes take place in the Solar chromosphere and magnetohydrodynamic generators. This paper argues that not all convective neutral flows generate electric fields and currents and it introduces the corresponding universal criterion for their formation, ∇×(U ×B )≠∂B /∂t , where U is the neutral flow velocity, B is the magnetic field, and t is time. This criterion does not depend on the conductivity tensor, σ ̂ . For many systems, the displacement current, ∂B /∂t , is negligible making the criterion even simpler. This theory also shows that the neutral-dynamo driver that generates E-fields and currents plays the same role as the DC electric current plays for the generation of the magnetic field in the Biot-Savart law.

  15. Simultaneous electricity generation and microbially-assisted electrosynthesis in ceramic MFCs.

    PubMed

    Gajda, Iwona; Greenman, John; Melhuish, Chris; Ieropoulos, Ioannis

    2015-08-01

    To date, the development of microbially assisted synthesis in Bioelectrochemical Systems (BESs) has focused on mechanisms that consume energy in order to drive the electrosynthesis process. This work reports--for the first time--on novel ceramic MFC systems that generate electricity whilst simultaneously driving the electrosynthesis of useful chemical products. A novel, inexpensive and low maintenance MFC demonstrated electrical power production and implementation into a practical application. Terracotta based tubular MFCs were able to produce sufficient power to operate an LED continuously over a 7 day period with a concomitant 92% COD reduction. Whilst the MFCs were generating energy, an alkaline solution was produced on the cathode that was directly related to the amount of power generated. The alkaline catholyte was able to fix CO2 into carbonate/bicarbonate salts. This approach implies carbon capture and storage (CCS), effectively capturing CO2 through wet caustic 'scrubbing' on the cathode, which ultimately locks carbon dioxide.

  16. Understanding electricity generation in osmotic microbial fuel cells through integrated experimental investigation and mathematical modeling.

    PubMed

    Qin, Mohan; Ping, Qingyun; Lu, Yaobin; Abu-Reesh, Ibrahim M; He, Zhen

    2015-11-01

    Osmotic microbial fuel cells (OsMFCs) are a new type of MFCs with integrating forward osmosis (FO). However, it is not well understood why electricity generation is improved in OsMFCs compared to regular MFCs. Herein, an approach integrating experimental investigation and mathematical model was adopted to address the question. Both an OsMFC and an MFC achieved similar organic removal efficiency, but the OsMFC generated higher current than the MFC with or without water flux, resulting from the lower resistance of FO membrane. Combining NaCl and glucose as a catholyte demonstrated that the catholyte conductivity affected the electricity generation in the OsMFC. A mathematical model of OsMFCs was developed and validated with the experimental data. The model predicated the variation of internal resistance with increasing water flux, and confirmed the importance of membrane resistance. Increasing water flux with higher catholyte conductivity could decrease the membrane resistance. PMID:26091574

  17. Hell and high water-financing electric generation in the `90`s

    SciTech Connect

    Emery, B.; Sierck, C.W.

    1996-09-01

    Electric utilities have long been one of this country`s most capital-intensive industries. For years the capital needed to construction generating facilities was obtained primarily through traditional means: investor-owned utilities issued equity securities and first mortgage bonds. However in the past decade changes have altered how capita is formed. In 1970 utilities built and financed virtually all electric generation. By 1990 nonutilities power producers accounted for 6% of all generating capacity, financed primarily by non traditional methods. An understanding of the history and transitions in utility capital formation provides insights for both transaction and regulatory specialists into how regulators may choose to restructure and deregulate the industry. Topics covered include the following: contract-based financing; cogeneration-contract-based financing comes into its own; utility capital formation in the 90`s, strains and gains; implication for regulatory change.

  18. Sauder Woodworking Company, a waste wood electric generating facility with Selective Catalytic Reduction

    SciTech Connect

    Johnson, N.H.

    1995-08-01

    Although NO{sub x} is the focus of this conference and Selective Catalytic Reduction (SCR) is the topic of this paper, it is important to understand the development of the project purpose and the reasons for the requirements of an SCR. Sauder Woodworking Company (SWC) generates waste wood as a byproduct of its manufacturing operation. Studies suggested that energy costs could be reduced by utilizing the waste wood to generate steam and electricity. Since the wood is dry, it is possible to utilize suspension burner technology. Two (2) 45,000 lb/hr boilers produce steam at 625 psig and 750{degrees}F. Each boiler is equipped with an economizer, mechanical dust collector, selective catalytic reduction, and an electrostatic precipitator. Electricity is produced from two (2) 3500 KW turbine generators operating in a condensing mode with steam extraction used for plant heating and process. As part of the plant design, an SCR was required for each boiler for environmental reasons.

  19. Understanding electricity generation in osmotic microbial fuel cells through integrated experimental investigation and mathematical modeling.

    PubMed

    Qin, Mohan; Ping, Qingyun; Lu, Yaobin; Abu-Reesh, Ibrahim M; He, Zhen

    2015-11-01

    Osmotic microbial fuel cells (OsMFCs) are a new type of MFCs with integrating forward osmosis (FO). However, it is not well understood why electricity generation is improved in OsMFCs compared to regular MFCs. Herein, an approach integrating experimental investigation and mathematical model was adopted to address the question. Both an OsMFC and an MFC achieved similar organic removal efficiency, but the OsMFC generated higher current than the MFC with or without water flux, resulting from the lower resistance of FO membrane. Combining NaCl and glucose as a catholyte demonstrated that the catholyte conductivity affected the electricity generation in the OsMFC. A mathematical model of OsMFCs was developed and validated with the experimental data. The model predicated the variation of internal resistance with increasing water flux, and confirmed the importance of membrane resistance. Increasing water flux with higher catholyte conductivity could decrease the membrane resistance.

  20. Fatigue damage of steam turbine shaft at asynchronous connections of turbine generator to electrical network

    NASA Astrophysics Data System (ADS)

    Bovsunovsky, A. P.

    2015-07-01

    The investigations of cracks growth in the fractured turbine rotors point out at theirs fatigue nature. The main reason of turbine shafts fatigue damage is theirs periodical startups which are typical for steam turbines. Each startup of a turbine is accompanied by the connection of turbine generator to electrical network. During the connection because of the phase shift between the vector of electromotive force of turbine generator and the vector of supply-line voltage the short-term but powerful reactive shaft torque arises. This torque causes torsional vibrations and fatigue damage of turbine shafts of different intensity. Based on the 3D finite element model of turbine shaft of the steam turbine K-200-130 and the mechanical properties of rotor steel there was estimated the fatigue damage of the shaft at its torsional vibrations arising as a result of connection of turbine generator to electric network.

  1. Maintaining Generation Adequacy in a Restructuring U.S. Electricity Industry

    SciTech Connect

    Hirst, E.; Hadley, S.

    1999-10-01

    Historically, decisions on the amounts, locations, types, and timing of investments in new generation have been made by vertically integrated utilities with approval from state public utility commissions. As the U.S. electricity industry is restructured, these decisions are being fragmented and dispersed among a variety of organizations. As generation is deregulated and becomes increasingly competitive, decisions on whether to build new generators and to retire, maintain, or repower existing units will increasingly be made by unregulated for-profit corporations. These decisions will be based largely on investor assessments of future profitability and only secondarily on regional reliability requirements. In addition, some customers will choose to face real-time (spot) prices and will respond to the occasionally very high prices by reducing electricity use at those times. Market-determined generation levels will, relative to centrally mandated reserve margins, lead to: (1) more volatile energy prices; (2) lower electricity costs and prices; and (3) a generation mix with more baseload, and less peaking, capacity. During the transition from a vertically integrated, regulated industry to a deintegrated, competitive industry, government regulators and system operators may continue to impose minimum-installed-capacity requirements on load-serving entities. As the industry gains experience with customer responses to real-time pricing and with operation of competitive intrahour energy markets, these requirements will likely disappear. We quantitatively analyzed these issues with the Oak Ridge Competitive Electricity Dispatch model (ORCED). Model results show that the optimal reserve margin depends on various factors, including fuel prices, initial mix of generation capacity, and customer response to electricity prices (load shapes and system load factor). Because the correct reserve margin depends on these generally unpredictable factors, mandated reserve margins might be

  2. Ocular microbiota and polymorphonuclear leucocyte recruitment during overnight contact lens wear.

    PubMed

    Stapleton, F; Willcox, M D; Sansey, N; Holden, B A

    1997-05-01

    Bacterial colonization of the ocular surface and contact lens (CL) and recruitment of polymorphonuclear leucocytes (PMN) during overnight CL wear was examined in 11 asymptomatic wearers. The ocular surface was more frequently colonized than the CL, with commensal bacteria (P < 0.05). Following sleep, more bacteria were recovered from the CL compared with daily use (P < 0.05), and fewer PMN were recruited compared to sleep without CL wear (P < 0.05). Overnight CL wear may inhibit physiological PMN recruitment to the cornea by preventing their access, by modifying the chemotactic signal or by altering the activation state of the recruited cells.

  3. Electric vehicles: Driving range

    NASA Astrophysics Data System (ADS)

    Kempton, Willett

    2016-09-01

    For uptake of electric vehicles to increase, consumers' driving-range needs must be fulfilled. Analysis of the driving patterns of personal vehicles in the US now shows that today's electric vehicles can meet all travel needs on almost 90% of days from a single overnight charge.

  4. Electrical generation and control of the valley carriers in a monolayer transition metal dichalcogenide

    NASA Astrophysics Data System (ADS)

    Ye, Yu; Xiao, Jun; Wang, Hailong; Ye, Ziliang; Zhu, Hanyu; Zhao, Mervin; Wang, Yuan; Zhao, Jianhua; Yin, Xiaobo; Zhang, Xiang

    2016-07-01

    Electrically controlling the flow of charge carriers is the foundation of modern electronics. By accessing the extra spin degree of freedom (DOF) in electronics, spintronics allows for information processes such as magnetoresistive random-access memory. Recently, atomic membranes of transition metal dichalcogenides (TMDCs) were found to support unequal and distinguishable carrier distribution in different crystal momentum valleys. This valley polarization of carriers enables a new DOF for information processing. A variety of valleytronic devices such as valley filters and valves have been proposed, and optical valley excitation has been observed. However, to realize its potential in electronics it is necessary to electrically control the valley DOF, which has so far remained a significant challenge. Here, we experimentally demonstrate the electrical generation and control of valley polarization. This is achieved through spin injection via a diluted ferromagnetic semiconductor and measured through the helicity of the electroluminescence due to the spin–valley locking in TMDC monolayers. We also report a new scheme of electronic devices that combine both the spin and valley DOFs. Such direct electrical generation and control of valley carriers opens up new dimensions in utilizing both the spin and valley DOFs for next-generation electronics and computing.

  5. Nitrate removal from groundwater driven by electricity generation and heterotrophic denitrification in a bioelectrochemical system.

    PubMed

    Tong, Yiran; He, Zhen

    2013-11-15

    This research aims to develop a new approach for in situ nitrate removal from groundwater by using a bioelectrochemical system (BES). The BES employs bioelectricity generated from organic compounds to drive nitrate moving from groundwater into the anode and reduces nitrate to nitrogen gas by heterotrophic denitrification. This laboratory study of a bench-scale BES demonstrated effective nitrate removal from both synthetic and actual groundwater. It was found that applying an electrical potential improved the nitrate removal and the highest nitrate removal rate of 208.2 ± 13.3g NO3(-)-Nm(-3) d(-1) was achieved at 0.8 V. Although the open circuit condition (no electricity generation) still resulted in a nitrate removal rate of 158.5 ± 4.2 gm(-3) d(-1) due to ion exchange, electricity production could inhibit ion exchange and prevent introducing other undesired ions into groundwater. The nitrate removal rate exhibited a linear relationship with the initial nitrate concentration in groundwater. The BES produced a higher current density of 33.4 Am(-3) and a higher total coulomb of 244.7 ± 9.1C from the actual groundwater than the synthetic groundwater, likely because other ions in the actual groundwater promoted ion movement to assist electricity generation. Further development of this BES will need to address several key challenges in anode feeding solution, ion competition, and long-term stability.

  6. Electrical generation and control of the valley carriers in a monolayer transition metal dichalcogenide

    NASA Astrophysics Data System (ADS)

    Ye, Yu; Xiao, Jun; Wang, Hailong; Ye, Ziliang; Zhu, Hanyu; Zhao, Mervin; Wang, Yuan; Zhao, Jianhua; Yin, Xiaobo; Zhang, Xiang

    2016-07-01

    Electrically controlling the flow of charge carriers is the foundation of modern electronics. By accessing the extra spin degree of freedom (DOF) in electronics, spintronics allows for information processes such as magnetoresistive random-access memory. Recently, atomic membranes of transition metal dichalcogenides (TMDCs) were found to support unequal and distinguishable carrier distribution in different crystal momentum valleys. This valley polarization of carriers enables a new DOF for information processing. A variety of valleytronic devices such as valley filters and valves have been proposed, and optical valley excitation has been observed. However, to realize its potential in electronics it is necessary to electrically control the valley DOF, which has so far remained a significant challenge. Here, we experimentally demonstrate the electrical generation and control of valley polarization. This is achieved through spin injection via a diluted ferromagnetic semiconductor and measured through the helicity of the electroluminescence due to the spin-valley locking in TMDC monolayers. We also report a new scheme of electronic devices that combine both the spin and valley DOFs. Such direct electrical generation and control of valley carriers opens up new dimensions in utilizing both the spin and valley DOFs for next-generation electronics and computing.

  7. Transient stability enhancement of electric power generating systems by 120-degree phase rotation

    DOEpatents

    Cresap, Richard L.; Taylor, Carson W.; Kreipe, Michael J.

    1982-01-01

    A method and system for enhancing the transient stability of an intertied three-phase electric power generating system. A set of power exporting generators (10) is connected to a set of power importing generators (20). When a transient cannot be controlled by conventional stability controls, and imminent loss of synchronism is detected (such as when the equivalent rotor angle difference between the two generator sets exceeds a predetermined value, such as 150 degrees), the intertie is disconnected by circuit breakers. Then a switch (30) having a 120-degree phase rotation, or a circuit breaker having a 120-degree phase rotation is placed in the intertie. The intertie is then reconnected. This results in a 120-degree reduction in the equivalent rotor angle difference between the two generator sets, making the system more stable and allowing more time for the conventional controls to stabilize the transient.

  8. Impact of Generator Flexibility on Electric System Costs and Integration of Renewable Energy

    SciTech Connect

    Palchak, D.; Denholm, P.

    2014-07-01

    Flexibility of traditional generators plays an important role in accommodating the increased variability and uncertainty of wind and solar on the electric power system. Increased flexibility can be achieved with changes to operational practices or upgrades to existing generation. One challenge is in understanding the value of increasing flexibility, and how this value may change given higher levels of variable generation. This study uses a commercial production cost model to measure the impact of generator flexibility on the integration of wind and solar generators. We use a system that is based on two balancing areas in the Western United States with a range of wind and solar penetrations between 15% and 60%, where instantaneous penetration of wind and solar is limited to 80%.

  9. Influence of Climate Change Mitigation Technology on Global Demands of Water for Electricity Generation

    SciTech Connect

    Kyle, G. Page; Davies, Evan; Dooley, James J.; Smith, Steven J.; Clarke, Leon E.; Edmonds, James A.; Hejazi, Mohamad I.

    2013-01-17

    Globally, electricity generation accounts for a large and potentially growing water demand, and as such is an important component to assessments of global and regional water scarcity. However, the current suite—as well as potential future suites—of thermoelectric generation technologies has a very wide range of water demand intensities, spanning two orders of magnitude. As such, the evolution of the generation mix is important for the future water demands of the sector. This study uses GCAM, an integrated assessment model, to analyze the global electric sector’s water demands in three futures of climate change mitigation policy and two technology strategies. We find that despite five- to seven-fold expansion of the electric sector as a whole from 2005 to 2095, global electric sector water withdrawals remain relatively stable, due to the retirement of existing power plants with water-intensive once-through flow cooling systems. In the scenarios examined here, climate policies lead to the large-scale deployment of advanced, low-emissions technologies such as carbon dioxide capture and storage (CCS), concentrating solar power, and engineered geothermal systems. In particular, we find that the large-scale deployment of CCS technologies does not increase long-term water consumption from hydrocarbon-fueled power generation as compared with a no-policy scenario without CCS. Moreover, in sensitivity scenarios where low-emissions electricity technologies are required to use dry cooling systems, we find that the consequent additional costs and efficiency reductions do not limit the utility of these technologies in achieving cost-effective whole-system emissions mitigation.

  10. What explains the increased utilization of Powder River Basin coal in electric power generation?

    SciTech Connect

    Gerking, S.; Hamilton, S.F.

    2008-11-15

    This article examines possible explanations for increased utilization of Powder River Basin (PRB) coal in electric power generation that occurred over the last two decades. Did more stringent environmental policy motivate electric power plants to switch to less polluting fuels? Or, did greater use of PRB coal occur because relative price changes altered input markets in favor of this fuel. A key finding is that factors other than environmental policy such as the decline in railroad freight rates together with elastic demand by power plants were major contributors to the increased utilization of this fuel.

  11. External electric field control of THz pulse generation in ambient air.

    PubMed

    Sun, Wen-Feng; Zhou, Yun-Song; Wang, Xin-Ke; Zhang, Yan

    2008-10-13

    A theoretical model has been proposed to describe the dependence of the THz wave generated in a laser-induced air plasma on the external electric field. Using this model we predict the following, (i) previously observed results show that the THz pulse enhances linearly with the increase of the external field; (ii) the THz pulse varies as a cosine function with the angle between the direction of the external electric field and the polarization of the incident exciting beam; (iii) and the amplitude is proportional to the square of the intensity of the incident pulse in a low energy region. These predictions are validated by our experiment.

  12. Evaluation of electricity generation from underground coal fires and waste banks

    SciTech Connect

    Chiasson, A.D.; Yavuzturk, C.; Walrath, D.E.

    2007-06-15

    A temperature response factors model of vertical thermal energy extraction boreholes is presented to evaluate electricity generation from underground coal fires and waste banks. Sensitivity and life-cycle cost analyses are conducted to assess the impact of system parameters on the production of 1 MW of electrical power using a theoretical binary-cycle power plant. Sensitivity analyses indicate that the average underground temperature has the greatest impact on the exiting fluid temperatures from the ground followed by fluid flow rate and ground thermal conductivity. System simulations show that a binary-cycle power plant may be economically feasible at ground temperatures as low as 190 {sup o}C.

  13. Generation of low-frequency electric and magnetic fields during large- scale chemical and nuclear explosions

    SciTech Connect

    Adushkin, V.V.; Dubinya, V.A.; Karaseva, V.A.; Soloviev, S.P.; Surkov, V.V.

    1995-06-01

    We discuss the main parameters of the electric field in the surface layer of the atmosphere and the results of the investigations of the natural electric field variations. Experimental investigations of the electromagnetic field for explosions in air are presented. Electromagnetic signals generated by underground nuclear and chemical explosions are discussed and explosions for 1976--1991 are listed. Long term anomalies of the earth`s electromagnetic field in the vicinity of underground explosions were also investigated. Study of the phenomenon of the irreversible shock magnetization showed that in the zone nearest to the explosion the quasistatic magnetic field decreases in inverse proportion to the distance.

  14. Electrical tuning and switching of an optical frequency comb generated in aluminum nitride microring resonators.

    PubMed

    Jung, Hojoong; Fong, King Y; Xiong, Chi; Tang, Hong X

    2014-01-01

    Aluminum nitride (AlN) has been shown to possess both strong Kerr nonlinearity and electro-optic Pockels effect. By combining these two effects, here we demonstrate on-chip reversible on/off switching of the optical frequency comb generated by an AlN microring resonator. We optimize the design of gating electrodes and the underneath resonator structure to effectively apply an electric field without increasing the optical loss. The switching of the comb is monitored by measuring one of the frequency comb peaks while varying the electric field. The controlled comb electro-optic response is investigated for direct comparison with the transient thermal effect.

  15. Electric field effect on optical harmonic generation at the exciton resonances in GaAs

    NASA Astrophysics Data System (ADS)

    Brunne, D.; Lafrentz, M.; Pavlov, V. V.; Pisarev, R. V.; Rodina, A. V.; Yakovlev, D. R.; Bayer, M.

    2015-08-01

    An electric field applied to a semiconductor reduces its crystal symmetry and modifies its electronic structure which is expected to result in changes of the linear and nonlinear response to optical excitation. In GaAs, we observe experimentally strong electric field effects on the optical second (SHG) and third (THG) harmonic generation. The SHG signal for the laser-light k vector parallel to the [001] crystal axis is symmetry forbidden in the electric-dipole approximation, but can be induced by an applied electric field in the vicinity of the 1 s exciton energy. Surprisingly, the THG signal, which is allowed in this geometry, is considerably reduced by the electric field. We develop a theory which provides good agreement with the experimental data. In particular, it shows that the optical nonlinearities for the 1 s exciton resonance are modified in an electric field by the Stark effect, which mixes the 1 s and 2 p exciton states of opposite parity. This mixing acts in opposite way on the SHG and THG processes, as it leads to the appearance of forbidden SHG in (001)-oriented GaAs and decreases the crystallographic THG.

  16. Recovery Act: Johnston Rhode Island Combined Cycle Electric Generating Plant Fueled by Waste Landfill Gas

    SciTech Connect

    Galowitz, Stephen

    2013-06-30

    The primary objective of the Project was to maximize the productive use of the substantial quantities of waste landfill gas generated and collected at the Central Landfill in Johnston, Rhode Island. An extensive analysis was conducted and it was determined that utilization of the waste gas for power generation in a combustion turbine combined cycle facility was the highest and best use. The resulting project reflected a cost effective balance of the following specific sub-objectives. 1) Meet environmental and regulatory requirements, particularly the compliance obligations imposed on the landfill to collect, process and destroy landfill gas. 2) Utilize proven and reliable technology and equipment. 3) Maximize electrical efficiency. 4) Maximize electric generating capacity, consistent with the anticipated quantities of landfill gas generated and collected at the Central Landfill. 5) Maximize equipment uptime. 6) Minimize water consumption. 7) Minimize post-combustion emissions. To achieve the Project Objective the project consisted of several components. 1) The landfill gas collection system was modified and upgraded. 2) A State-of-the Art gas clean up and compression facility was constructed. 3) A high pressure pipeline was constructed to convey cleaned landfill gas from the clean-up and compression facility to the power plant. 4) A combined cycle electric generating facility was constructed consisting of combustion turbine generator sets, heat recovery steam generators and a steam turbine. 5) The voltage of the electricity produced was increased at a newly constructed transformer/substation and the electricity was delivered to the local transmission system. The Project produced a myriad of beneficial impacts. 1) The Project created 453 FTE construction and manufacturing jobs and 25 FTE permanent jobs associated with the operation and maintenance of the plant and equipment. 2) By combining state-of-the-art gas clean up systems with post combustion emissions control

  17. An overnight habitat for expanding lunar surface exploration

    NASA Astrophysics Data System (ADS)

    Schreiner, Samuel S.; Setterfield, Timothy P.; Roberson, Daniel R.; Putbrese, Benjamin; Kotowick, Kyle; Vanegas, Morris D.; Curry, Mike; Geiger, Lynn M.; Barmore, David; Foley, Jordan J.; LaTour, Paul A.; Hoffman, Jeffrey A.; Head, James W.

    2015-07-01

    This paper presents the conceptual design and analysis of a system intended to increase the range, scientific capability, and safety of manned lunar surface exploration, requiring only a modest increase in capability over the Apollo mission designs. The system is intended to enable two astronauts, exploring with an unpressurized rover, to remove their space suits for an 8-h rest away from the lunar base and then conduct a second day of surface exploration before returning to base. This system is composed of an Environmental Control and Life Support System on the rover, an inflatable habitat, a solar shield and a solar power array. The proposed system doubles the distance reachable from the lunar base, thus increasing the area available for science and exploration by a factor of four. In addition to increasing mission capability, the proposed system also increases fault tolerance with an emergency inflatable structure and additional consumables to mitigate a wide range of suit or rover failures. The mass, volume, and power analyses of each subsystem are integrated to generate a total system mass of 124 kg and a volume of 594 L, both of which can be accommodated on the Apollo Lunar Roving Vehicle with minor improvements.

  18. Comparative assessment of the environmental impact of wastes from electricity generation systems

    SciTech Connect

    Torres, C. [Instituto de Medio Ambiente Smith, G.M.; Linsley, G.; Hossain, S.

    1994-12-31

    The paper describes an outline methodology for assessing and comparing the environmental impact arising from management of the wastes from nuclear and other electricity generation systems. The assessment framework is applicable to wastes from all generation systems, including nuclear, fossil and renewable fuel systems, and can also be applied to the management of mixed hazardous waste. The major energy technologies in terms of waste production can be classified according to three major categories of fuels: fossil, nuclear and renewable. The emphasis in this description is on nuclear utility low-level and mixed wastes and waste streams. The methodology may be used to support the project on Data Bases and Methodologies for Comparative Assessment of Different Energy Sources for Electricity Generation (DECADES project, (2)) which is being developed by the International Atomic Energy Agency in collaboration with other international agencies. The DECADES project has the overall objective to improve the abilities for comparative assessment of energy chains for electricity generation. The objective of a methodology such as that described here is to ensure that waste management aspects are included effectively in comparative assessments of energy systems. This paper discusses the waste strams arising from nuclear power plants.

  19. Electricity generation from synthetic acid-mine drainage (AMD) water using fuel cell technologies

    SciTech Connect

    Shaoan Cheng; Brian A. Dempsey; Bruce E. Logan

    2007-12-15

    Acid-mine drainage (AMD) is difficult and costly to treat. We investigated a new approach to AMD treatment using fuel cell technologies to generate electricity while removing iron from the water. Utilizing a recently developed microbial fuel cell architecture, we developed an acid-mine drainage fuel cell (AMD-FC) capable of abiotic electricity generation. The AMD-FC operated in fed-batch mode generated a maximum power density of 290 mW/m{sup 2} at a Coulombic efficiency greater than 97%. Ferrous iron was completely removed through oxidation to insoluble Fe(III), forming a precipitate in the bottom of the anode chamber and on the anode electrode. Several factors were examined to determine their effect on operation, including pH, ferrous iron concentration, and solution chemistry. Optimum conditions were a pH of 6.3 and a ferrous iron concentration above about 0.0036 M. These results suggest that fuel cell technologies can be used not only for treating AMD through removal of metals from solution, but also for producing useful products such as electricity and recoverable metals. Advances being made in wastewater fuel cells will enable more efficient power generation and systems suitable for scale-up. 35 refs., 8 figs.

  20. A distributed big data storage and data mining framework for solar-generated electricity quantity forecasting

    NASA Astrophysics Data System (ADS)

    Wang, Jianzong; Chen, Yanjun; Hua, Rui; Wang, Peng; Fu, Jia

    2011-11-01

    Photovoltaic is a method of generating electrical power by converting solar radiation into direct current electricity using semiconductors that exhibit the photovoltaic effect. Photovoltaic power generation employs solar panels composed of a number of solar cells containing a photovoltaic material. Due to the growing demand for renewable energy sources, the manufacturing of solar cells and photovoltaic arrays has advanced considerably in recent years. Solar photovoltaics are growing rapidly, albeit from a small base, to a total global capacity of 40,000 MW at the end of 2010. More than 100 countries use solar photovoltaics. Driven by advances in technology and increases in manufacturing scale and sophistication, the cost of photovoltaic has declined steadily since the first solar cells were manufactured. Net metering and financial incentives, such as preferential feed-in tariffs for solar-generated electricity; have supported solar photovoltaics installations in many countries. However, the power that generated by solar photovoltaics is affected by the weather and other natural factors dramatically. To predict the photovoltaic energy accurately is of importance for the entire power intelligent dispatch in order to reduce the energy dissipation and maintain the security of power grid. In this paper, we have proposed a big data system--the Solar Photovoltaic Power Forecasting System, called SPPFS to calculate and predict the power according the real-time conditions. In this system, we utilized the distributed mixed database to speed up the rate of collecting, storing and analysis the meteorological data. In order to improve the accuracy of power prediction, the given neural network algorithm has been imported into SPPFS.By adopting abundant experiments, we shows that the framework can provide higher forecast accuracy-error rate less than 15% and obtain low latency of computing by deploying the mixed distributed database architecture for solar-generated electricity.

  1. A distributed big data storage and data mining framework for solar-generated electricity quantity forecasting

    NASA Astrophysics Data System (ADS)

    Wang, Jianzong; Chen, Yanjun; Hua, Rui; Wang, Peng; Fu, Jia

    2012-02-01

    Photovoltaic is a method of generating electrical power by converting solar radiation into direct current electricity using semiconductors that exhibit the photovoltaic effect. Photovoltaic power generation employs solar panels composed of a number of solar cells containing a photovoltaic material. Due to the growing demand for renewable energy sources, the manufacturing of solar cells and photovoltaic arrays has advanced considerably in recent years. Solar photovoltaics are growing rapidly, albeit from a small base, to a total global capacity of 40,000 MW at the end of 2010. More than 100 countries use solar photovoltaics. Driven by advances in technology and increases in manufacturing scale and sophistication, the cost of photovoltaic has declined steadily since the first solar cells were manufactured. Net metering and financial incentives, such as preferential feed-in tariffs for solar-generated electricity; have supported solar photovoltaics installations in many countries. However, the power that generated by solar photovoltaics is affected by the weather and other natural factors dramatically. To predict the photovoltaic energy accurately is of importance for the entire power intelligent dispatch in order to reduce the energy dissipation and maintain the security of power grid. In this paper, we have proposed a big data system--the Solar Photovoltaic Power Forecasting System, called SPPFS to calculate and predict the power according the real-time conditions. In this system, we utilized the distributed mixed database to speed up the rate of collecting, storing and analysis the meteorological data. In order to improve the accuracy of power prediction, the given neural network algorithm has been imported into SPPFS.By adopting abundant experiments, we shows that the framework can provide higher forecast accuracy-error rate less than 15% and obtain low latency of computing by deploying the mixed distributed database architecture for solar-generated electricity.

  2. 75 FR 63198 - Notice of Availability of the Record of Decision for the Ivanpah Solar Electric Generating System...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-14

    ...] Notice of Availability of the Record of Decision for the Ivanpah Solar Electric Generating System Project... the California Desert Conservation Area (CDCA) Plan for the Ivanpah Solar Electric Generating System....gov . SUPPLEMENTARY INFORMATION: The ISEGS Project was proposed by Solar Partners I, Solar Partners...

  3. Assessing Climate Change Impacts on Electric Power Generation in the Western Interconnection

    NASA Astrophysics Data System (ADS)

    Bartos, M. D.; Chester, M.

    2014-12-01

    In recent years, concerns have grown over the potential impacts of climate change on electricity generation. Water resources are integral to the production of thermoelectric and hydroelectric power, and droughts are expected to become more frequent, severe, and longer-lasting over the course of the twenty-first century. Many generation technologies—including gas turbines and solar cells—are also vulnerable to changes in local climatic conditions like ambient air temperature. As extreme weather becomes more common, methods are needed to assess the impacts of climate change on regional power systems. However, these methods must also account for (1) heterogeneity in generation technologies, and (2) local variation in climatic conditions. This study uses a physically-based modeling system to assess the vulnerability of electric power infrastructure in the Western Interconnection. Climatic and hydrologic parameters relevant to power generation are identified for six generation technologies. Downscaled climate forcings are then used as inputs to a physically-based modeling system, consisting of the Variable Infiltration Capacity (VIC) hydrological model and the RBM one-dimensional stream temperature model. Impacts to generating capacity are estimated directly from changes in modeled climatic and hydrologic parameters, using functional relationships unique to each generating technology. A preliminary analysis of 1,302 power stations in the Western Interconnection reveals decreases in summertime generating capacity of 8-22%, with the largest impacts occurring at thermoelectric and hydroelectric facilities in the Pacific Northwest and California. Impacts to base-load thermoelectric plants are mitigated by recirculating cooling systems, which reduce the performance penalty of low flows and high water temperatures. Climate impacts on solar and wind capacity are relatively small, indicating that these energy sources may play a more prominent role as conventional generation

  4. Electricity prices in a competitive environment: Marginal cost pricing of generation services and financial status of electric utilities. A preliminary analysis through 2015

    SciTech Connect

    1997-08-01

    The emergence of competitive markets for electricity generation services is changing the way that electricity is and will be priced in the United States. This report presents the results of an analysis that focuses on two questions: (1) How are prices for competitive generation services likely to differ from regulated prices if competitive prices are based on marginal costs rather than regulated {open_quotes}cost-of-service{close_quotes} pricing? (2) What impacts will the competitive pricing of generation services (based on marginal costs) have on electricity consumption patterns, production costs, and the financial integrity patterns, production costs, and the financial integrity of electricity suppliers? This study is not intended to be a cost-benefit analysis of wholesale or retail competition, nor does this report include an analysis of the macroeconomic impacts of competitive electricity prices.

  5. Electrical Control of Exciton-Enhanced Second-Harmonic Generation in Monolayer WSe2

    NASA Astrophysics Data System (ADS)

    Seyler, Kyle; Schaibley, John; Gong, Pu; Rivera, Pasqual; Jones, Aaron; Wu, Sanfeng; Yan, Jiaqiang; Mandrus, David; Yao, Wang; Xu, Xiaodong

    2015-03-01

    Nonlinear optical frequency conversion, in which optical fields interact with a nonlinear medium to produce new field frequencies, is ubiquitous in modern photonic systems. However, the nonlinear electric susceptibilities that give rise to such phenomena are often challenging to tune in a given material, and so far, dynamical control of optical nonlinearities remains confined to research labs. In this talk, we report a new mechanism to electrically control second-order optical nonlinearities in monolayer WSe2. We show that the intensity of second-harmonic generation (SHG) at its lowest exciton resonance is widely tunable through electrostatic doping in a field-effect transistor device. Such remarkable tunability arises from the strong exciton charging effects in monolayer semiconductors, which allow for exceptional control over the exciton and trion oscillator strengths. Our study paves the way for a new platform of chip-scale, electrically tunable nonlinear optical devices based on two-dimensional semiconductors.

  6. Identification of advantageous electricity generation options in sub-Saharan Africa integrating existing resources

    NASA Astrophysics Data System (ADS)

    Szabó, Sándor; Moner-Girona, Magda; Kougias, Ioannis; Bailis, Rob; Bódis, Katalin

    2016-10-01

    Pioneering approaches are needed to accelerate universal access to electricity while simultaneously transitioning to reliable, sustainable and affordable energy systems. In sub-Saharan Africa (SSA), the challenges lie in attracting the private sector to complement public investments. Here, we present an integrated ‘low-hanging-fruit’ approach aimed at boosting private investment and speeding up the deployment of renewable energy systems in SSA. We analyse the potential of existing energy infrastructure, where a significant upfront investment has already been made, to be exploited for electricity generation. We develop a comprehensive methodology to identify and select suitable locations in SSA and estimate their potential for exploitation. These locations have been further analysed in terms of power capacity potential, electricity output, investments needed and population to be benefited. This strategy to attract additional finance can easily be reproduced, engaging private investors while simultaneously helping to achieve the United Nations (UN) Sustainable Development Goals on energy.

  7. Analysis of energy and water management in terms of fuel-cell electricity generation

    NASA Astrophysics Data System (ADS)

    Menzer, R.; Höhlein, B.

    Hydrogen-powered low-temperature fuel cells (PEFCs) are the energy conversion units in vehicles with methanol as the energy carrier and a power train consisting of the following main units: methanol reformer (H2 production) including catalytic converter, gas treatment, PEFC with peripheral units, electric motor with electric controllers and gearbox. The process engineering analysis is based on a simulation model and describes the energy and water management as a function of different assumptions as well as operating and ambient conditions for net electricity generation in a PEFC-powered power train. In particular, it presents an approach for balancing both water recovery (PEFC) and the use of water for the methanol reforming process as well as for the humidification of the PEFC. The overall balances present an optimised energy management including peripheral air compression for the PEFC.

  8. Electricity generation from carbon monoxide in a single chamber microbial fuel cell.

    PubMed

    Mehta, P; Hussain, A; Tartakovsky, B; Neburchilov, V; Raghavan, V; Wang, H; Guiot, S R

    2010-05-01

    Electricity production from carbon monoxide (CO) is demonstrated in a single chamber microbial fuel cell (MFC) with a CoTMPP-based air cathode. The MFC was inoculated with anaerobic sludge and continuously sparged with CO as a sole carbon source. Volumetric power output was maximized at a CO flow rate of 4.8LLR(-1)d(-1) reaching 6.4mWLR(-1). Several soluble and gaseous degradation products including hydrogen, methane, and acetate were detected, resulting in a relatively low apparent Coulombic efficiency of 8.7%. Tests also demonstrated electricity production from hydrogen and acetate with the highest and fastest increase in voltage exhibited after acetate injection. It is hypothesized that electricity generation in a CO-fed MFC is accomplished by a consortium of carboxydotrophic and carbon monoxide - tolerant anodophilic microorganisms. PMID:25919620

  9. Is Everything All Right at Night? Measuring User Response to Overnight Library Services

    ERIC Educational Resources Information Center

    Chrzastowski, Tina E.; Nutefall, Jennifer E.

    2016-01-01

    A multiple methods study was conducted over three academic terms during the 2015 fiscal year at Santa Clara University Library to assess the impact and value of overnight library hours. A survey was conducted after midnight during times the Library was open 24 hours, five days a week (24/5), the last two weeks of the quarter. The survey was…

  10. EVALUATION OF SPERM CHROMATIN STRUCTURE ASSAY (SCSA REGISTERED TRADEMARK) IN HUMAN SPERM AFTER SIMULATED OVERNIGHT SHIPMENT

    EPA Science Inventory

    Home semen collection kits allow men to collect a sample at their convenience and send it via overnight mail to the laboratory. Benefits of this approach include facilitated sample collection from different geographic locations, minimized variability through analysis by a central...

  11. Effects of Model Performances on Music Skill Acquisition and Overnight Memory Consolidation

    ERIC Educational Resources Information Center

    Cash, Carla D.; Allen, Sarah E.; Simmons, Amy L.; Duke, Robert A.

    2014-01-01

    This study was designed to investigate the extent to which the presentation of an auditory model prior to learning a novel melody affects performance during active practice and the overnight consolidation of procedural memory. During evening training sessions, 32 nonpianist musicians practiced a 13-note keyboard melody with their left…

  12. EVALUATION OF CHROMOMYCIN A3 ASSAY IN HUMAN SPERM AFTER SIMULATED OVERNIGHT SHIPMENT

    EPA Science Inventory

    EVALUATION OF CHROMOMYCIN A3ASSAY IN HUMAN SPERM AFTER SIMULATED OVERNIGHT SHIPMENT.
    SC Jeffay1, R Morris Buus1, LF Strader1, AF Olshan2, DP Evenson3, SD Perreault1. 1US EPA/ORD, RTP, NC;2UNC-CH, Chapel Hill, NC;3SDSU, Brookings, SD.

    Semen collection kits that allow ...

  13. Freezing/thawing effect on sewage sludge degradation and electricity generation in microbial fuel cell.

    PubMed

    Chen, Yuejia; Jiang, Junqiu; Zhao, Qingliang

    2014-01-01

    The effect of sludge freezing/thawing on its disintegration and subsequent use as substrate in a microbial fuel cell (MFC) was investigated to enhance organic matter degradation and electricity generation. Experimental results indicated that long freezing time (more than 48 h) was effective in disintegrating the sludge collected from the secondary sedimentation tank of a wastewater treatment plant. Freezing/thawing pretreatment could enhance the degradation of total chemical oxygen demand (COD) and electricity generation in MFC due to the higher concentration of soluble COD and ammonium nitrogen available in the pretreated sludge. The removal efficiency of total COD was increased from 25.3% (raw sludge as substrate) to 66.2% and the maximum power output was increased from 8.9 (raw sludge as substrate) to 10.2 W/m³ in MFC.

  14. Electricity generation by microorganisms in the sediment-water interface of an extreme acidic microcosm.

    PubMed

    García-Muñoz, Juan; Amils, Ricardo; Fernández, Víctor M; De Lacey, Antonio L; Malki, Moustafa

    2011-06-01

    The attachment of microorganisms to electrodes is of great interest for electricity generation in microbial fuel cells (MFC) or other applications in bioelectrochemical systems (BES). In this work, a microcosm of the acidic ecosystem of Río Tinto was built and graphite electrodes were introduced at different points. This allowed the study of electricity generation in the sediment/water interface and the involvement of acidophilic microorganisms as biocatalysts of the anodic and cathodic reactions in a fuel-cell configuration. Current densities and power outputs of up to 3.5 A/m² and 0.3 W/m², respectively, were measured at pH 3. Microbial analyses of the electrode surfaces showed that Acidiphilium spp., which uses organic compounds as electron donors, were the predominant biocatalysts of the anodic reactions, whereas the aerobic iron oxidizers Acidithiobacillus ferrooxidans and Leptospirillum spp. were detected mainly on the cathode surface.

  15. Puget Sound Area Electric Reliability Plan. Appendix B : Local Generation Evaluation : Draft Environmental Impact Statement.

    SciTech Connect

    United States. Bonneville Power Administration.

    1991-09-01

    The information and data contained in this Appendix was extracted from numerous sources. The principle sources used for technical data were Bonneville Power Administration's 1990 Resource Program along with its technical appendix, and Chapter 8 of the Draft 1991 Northwest Conservation and Electric Power Plan. All cost data is reported 1988 dollars unless otherwise noted. This information was supplemented by other data developed by Puget Sound utilities who participated on the Local Generation Team. Identifying generating resources available to the Puget Sound area involved a five step process: (1) listing all possible resources that might contribute power to the Puget Sound area, (2) characterizing the technology/resource status, cost and operating characteristics of these resources, (3) identifying exclusion criteria based on the needs of the overall Puget Sound Electric Reliability Plan study, (4) applying these criteria to the list of resources, and (5) summarizing of the costs and characteristics of the final list of resources. 15 refs., 20 tabs.

  16. Generation of Electric Energy and Desalinating Water from Solar Energy and the Oceans Hydropower

    NASA Astrophysics Data System (ADS)

    Elfikky, Niazi

    Brief.All warnings and fears about the environment in our Earth planet due to the serious effects of the industrial revolution were certainly predicted early. But the eager contest and the powerful desire for more profits beside the human interest for welfare and development closed all minds about the expected severe destuctive impacts on our earth planet. Also, we have to remember that the majority of the African, Asian and Latin American countries are still in the first stage of their development and if they will be left to generate all their demand of energy by the conventional machine e.g (Fossil Fuel, Biofuel and Nuclear Fuel), then our Earth planet will confront an endless and ceasless severe destructive impacts due to the encroach of the released hot Carbon Doxide and hot vapours of Acids which will never forgive any fruitful aspect in our Earth Planet from destruction. 1. Importance of the New Project. Building the Extra cheap, clean Power plants with safe and smooth Operation in addition to the long life time in service for generating enough and plentiful electric energy the sustainable renwable resources will invigorate the foresaking of all Nuclear, Fossil and Biofuel power plants to avoide the nuclear hazards and stop releasing the hot carbon doxide, hot acids for the recovery of our ill environment. Also, the main sustainable, renewable, and cheap resources for generating the bulky capacity of the electric energy in our project are the Sun and the Oceans in addition to all Seas Surrounding all Continents in our Earth planet. Therefore, our recourses are so much enormous plentiful, clean, and renewable. 2. .Generation of Electricity from Solar Energy by Photovoltiac Cells (PVCs) or Concentrated Solar Power (CSP). Characteristics of Photovoltiac Cells (PVCs). It is working only by Sun's Light (Light photons) and its efficiency will decrease as the Solar Thermal Radiation will increase, i.e. as the temerature of the Solar Voltiac will increase, its output

  17. Process for generating electricity in a pressurized fluidized-bed combustor system

    DOEpatents

    Kasper, Stanley

    1991-01-01

    A process and apparatus for generating electricity using a gas turbine as part of a pressurized fluidized-bed combustor system wherein coal is fed as a fuel in a slurry in which other constituents, including a sulfur sorbent such as limestone, are added. The coal is combusted with air in a pressurized combustion chamber wherein most of the residual sulfur in the coal is captured by the sulfur sorbent. After particulates are removed from the flue gas, the gas expands in a turbine, thereby generating electric power. The spent flue gas is cooled by heat exchange with system combustion air and/or system liquid streams, and the condensate is returned to the feed slurry.

  18. [Effect of the initial anode potential on electricity generation in microbial fuel cell].

    PubMed

    Fan, Ming-Zhi; Liang, Peng; Cao, Xiao-Xin; Huang, Xia

    2008-01-01

    The initial anode potential of the microbial fuel cell (MFC) was changed by additional circuit in the anode chamber, and the influence of the initial anode potential on the electricigens was studied. When the initial anode potential was 350 mV (vs Hg/Hg2 Cl2), the growth of microorganisms was much slower than that of the microorganisms which grew on the anode with an initial potential of -200 mV or 200 mV (vs Hg/Hg2 Cl2). After stable electricity generation, the anode resistances of the three MFCs, which had initial anode potentials of 350 mV, 200 mV and -200 mV respectively, were 71 Omega, 43 Omega and 80 Omega. The community structures in MFCs, before and after the electricity generation, were also studied by denaturing gradient gel electrophoresis (DGGE). Clostridium sticklandii, Pseudomonas mendocina and Paenibacillus taejonensis were the three most enriched strains on the anode.

  19. Integrated capacity planning for electricity generation: A fuzzy environmental policy analysis approach

    SciTech Connect

    Nasiri, F.; Huang, G.

    2008-07-01

    This study proposes an integrated model for capacity planning in electricity generation. It utilizes a multiple-criteria linear programming to incorporate cost and environmental objectives into the planning. To treat the uncertainties embedded in definition of model parameters, the concept of decision-maker degree of optimism will be used. Optimization of the model provides different planning scenarios. To determine the best compromise plan, a post-optimization assessment based on fuzzy set theory concepts is developed. The proposed methodology is employed for a medium-term capacity planning in Canada's electricity generation sector. The results approve a major capacity growth for natural gas facilities accompanied by retirement of most coal-burning facilities.

  20. Novel Two-Dimensional Mechano-Electric Generators and Sensors Based on Transition Metal Dichalcogenides

    PubMed Central

    Yu, Sheng; Eshun, Kwesi; Zhu, Hao; Li, Qiliang

    2015-01-01

    Transition metal dichalcogenides (TMDCs), such as MoS2 and WSe2, provide two-dimensional atomic crystals with semiconductor band gap. In this work, we present a design of new mechano-electric generators and sensors based on transition metal dichalcogenide nanoribbon PN junctions and heterojunctions. The mechano-electric conversion was simulated by using a first-principle calculation. The output voltage of MoS2 nanoribbon PN junction increases with strain, reaching 0.036 V at 1% strain and 0.31 V at 8% strain, much larger than the reported results. Our study indicates that the length, width and layer number of TMDC nanoribbon PN junctions have an interesting but different impact on the voltage output. Also, the results indicate that doping position and concentration only cause a small fluctuation in the output voltage. These results have been compared with the mechano-electric conversion of TMDC heterojunctions. Such novel mechano-electric generators and sensors are very attractive for applications in future self-powered, wearable electronics and systems. PMID:26238461

  1. Enhanced magnetic energy harvesting properties of magneto-mechano-electric generator by tailored geometry

    NASA Astrophysics Data System (ADS)

    Annapureddy, Venkateswarlu; Lee, Ha Young; Yoon, Woon-Ha; Woo, Hyun-Jae; Lee, Ji-Hye; Palneedi, Haribabu; Kim, Hwee-Jong; Choi, Jong-Jin; Jeong, Dae-Yong; Yi, Sam Nyung; Ryu, Jungho

    2016-08-01

    By tailoring the truncated shape of a cantilever structured magneto-mechano-electric (MME) generator that is composed of a piezoelectric single crystal fiber composite and a magnetostrictive Ni plate, a superior output harvesting power density of over 680% was obtained as compared to a typical rectangular shaped generator. The effect of the MME generator's shape on the strain distribution induced by magnetostriction and vibration characteristics and harvesting properties were simulated by finite element analysis modeling and confirmed experimentally, respectively. The truncated shape was effective for not only utilizing a more uniform in-plane strain distribution in the active piezoelectric area but also magnifying the flexural vibration amplitude, which in turn can make the generator more powerful under tiny magnetic oscillations.

  2. Development and electrical test of a 30 kVA class fully superconducting generator

    SciTech Connect

    Tsukamoto, O.; Amemiya, N.; Yamagishi, K.; Takao, T.; Akita, S.; Torii, S.; Ohishi, K.; Shimizu, H.

    1994-07-01

    The authors are developing a 4 pole 50 Hz 30 kVA class fully superconducting generator to investigate the characteristics of superconducting armature windings subject to a rotating magnetic field. Compared with other fully superconducting generators that have been developed and tested, this machine is designed to obtain a higher armature current. It is generally observed in coils wound from AC superconducting cable that the AC quench current of the coil is much lower than its DC quench current. Countermeasures against these AC current degradation phenomena were developed and applied to the AC cable and armature winding of their generator. In the paper, results of the electrical tests of the generator are presented and the validity of the countermeasures is discussed.

  3. Design of a low-cost thermoacoustic electricity generator and its experimental verification

    SciTech Connect

    Backhaus, Scott N; Yu, Z; Jaworski, A J

    2010-01-01

    This paper describes the design and testing of a low cost thermoacoustic generator. A travelling-wave thermoacoustic engine with a configuration of a looped-tube resonator is designed and constructed to convert heat to acoustic power. A commercially available, low-cost loudspeaker is adopted as the alternator to convert the engine's acoustic power to electricity. The whole system is designed using linear thermoacoustic theory. The optimization of different parts of the thermoacoustic generator, as well as the matching between the thermoacoustic engine and the alternator are discussed in detail. A detailed comparison between the preliminary test results and linear thermoacoustic predictions is provided.

  4. Electrically generated eddies at an eightfold stagnation point within a nanopore

    PubMed Central

    Sherwood, J. D.; Mao, M.; Ghosal, S.

    2014-01-01

    Electrically generated flows around a thin dielectric plate pierced by a cylindrical hole are computed numerically. The geometry represents that of a single nanopore in a membrane. When the membrane is uncharged, flow is due solely to induced charge electroosmosis, and eddies are generated by the high fields at the corners of the nanopore. These eddies meet at stagnation points. If the geometry is chosen correctly, the stagnation points merge to form a single stagnation point at which four streamlines cross at a point and eight eddies meet. PMID:25489206

  5. Generation of coronal electric currents due to convective motions on the photosphere

    NASA Technical Reports Server (NTRS)

    Sakurai, T.; Levine, R. H.

    1981-01-01

    Generation of electric currents in a magnetized plasma overlying a dense convective layer is studied, assuming that the magnetic field perturbation is small and satisfies the force-free equation. Currents are produced by rotational motions on the boundary in the case of a uniform equilibrium field. In a simple two-dimensional bipolar configuration, however, both irrotational and incompressible motions give rise to currents, and the current density has a peak at the magnetic neutral line. Scaling laws for the current density as well as for the stored magnetic energy are derived, and the possibility of heating the solar corona through the dissipation of coronal currents generated in this way is discussed.

  6. French wind generator systems. [as auxiliary power sources for electrical networks

    NASA Technical Reports Server (NTRS)

    Noel, J. M.

    1973-01-01

    The experimental design of a wind driven generator with a rated power of 800 kilovolt amperes and capable of being connected to the main electrical network is reported. The rotor is a three bladed propeller; each blade is twisted but the fixed pitch is adjustable. The asynchronous 800-kilovolt ampere generator is driven by the propeller through a gearbox. A dissipating resistor regulates the machine under no-load conditions. The first propeller on the machine lasted 18 months; replacement of the rigid propeller with a flexible structure resulted in breakdown due to flutter effects.

  7. A study of electrical generating capacities of self-discharging slim holes

    SciTech Connect

    Pritchett, J.W.

    1996-01-24

    Theoretical calculations have been performed to estimate the electrical generating capacities of small-diameter geothermal wells for off-grid rural electrification using wellhead generators. In these applications, generating capacities of interest are typically in the range 100-1000 kWe. The approach amounted to (1) calculating the “wellhead discharge characteristics” (water/steam discharge rates as functions of wellhead pressure) for a variety of hypothetical well and reservoir descriptions, (2) employing a mathematical representation for the net generating capacity of a wellhead powerplant as a function of its operating inlet pressure and steam inlet rate, and (3) varying the wellhead (= turbine inlet) pressure to identify the “optimum” pressure value at which the net electrical power is maximized. Calculations were carried out for well diameters from 75 mm to 300 mm, for well depths from 300 to 1200 meters, for reservoir temperatures from 100°C to 240°C, for piezometric surface depths (related to shut-in reservoir pressure) from zero to 250 meters, and for downhole productivity indices from 2 kg/s/bar to infinity. A few cases were also included in which the CO2 content of the reservoir fluid was non-zero (up to 1% by mass in the brine). Both backpressure and condensing single-flash steam turbine powerplants were considered. The study was restricted to vertical wells of uniform inside diameter and to all-liquid in-situ reservoir fluids. Over fifteen thousand combinations of the above parameters were examined. The results indicate that slim holes as small as 100 mm inside diameter penetrating reservoirs with temperatures as low as 150°C can produce useful amounts of electrical power using condensing wellhead turbines (> 100 kWe). For higher reservoir temperatures, the electrical capacity of such a well can exceed one megawatt.

  8. ReEDS Modeling of the President's 2020 U.S. Renewable Electricity Generation Goal (Presentation)

    SciTech Connect

    Zinaman, O.; Mai, T.; Lantz, E.; Gelman, R.; Porro, G.

    2014-05-01

    President Obama announced in 2012 an Administration Goal for the United States to double aggregate renewable electricity generation from wind, solar, and geothermal sources by 2020. This analysis, using the Regional Energy Deployment System (ReEDS) model, explores a full range of future renewable deployment scenarios out to 2020 to assess progress and outlook toward this goal. Under all modeled conditions, consisting of 21 scenarios, the Administration Goal is met before 2020, and as early as 2015.

  9. Interim Project Results: United Parcel Service's Second-Generation Hybrid-Electric Delivery Vans (Fact Sheet)

    SciTech Connect

    Not Available

    2012-01-01

    This fact sheet describes the performance evaluation of United Parcel Service's second-generation hybrid-electric delivery vans. The Fleet Test and Evaluation Team at the National Renewable Energy Laboratory (NREL) is evaluating the 18-month, in-service performance of 11 of these vans along with 11 comparable conventional diesel vans operating in Minneapolis, Minnesota. As a complement to the field study, the team recently completed fuel economy and emissions testing at NREL's Renewable Fuels and Lubricants (ReFUEL) laboratory.

  10. Peptide assembly-driven metal-organic framework (MOF) motors for micro electric generators.

    PubMed

    Ikezoe, Yasuhiro; Fang, Justin; Wasik, Tomasz L; Uemura, Takashi; Zheng, Yongtai; Kitagawa, Susumu; Matsui, Hiroshi

    2015-01-14

    Peptide-metal-organic framework (Pep-MOF) motors, whose motions are driven by anisotropic surface tension gradients created via peptide self-assembly around frameworks, can rotate microscopic rotors and magnets fast enough to generate an electric power of 0.1 μW. A new rigid Pep-MOF motor can be recycled by refilling the peptide fuel into the nanopores of the MOF.

  11. High electric field effects on the thermal generation in hydrogenated amorphous silicon

    SciTech Connect

    Ilie, A.; Equer, B.

    1997-07-01

    The authors have studied the electric field dependence of the electron-hole thermal generation process in hydrogenated amorphous silicon. A model was developed which takes into account the Poole-Frenkel effect and the thermally assisted tunneling. In order to explain the experimental results it was necessary to consider a strong electron-lattice interaction describing the carrier tunneling mechanism. Deep defects relaxation is also discussed.

  12. A Bidding Methodology by Nash Equilibrium for Finite Generators Participating in Imperfect Electricity Markets

    NASA Astrophysics Data System (ADS)

    Satyaramesh, P. V.

    2014-01-01

    This paper presents an application of finite n-person non-cooperative game theory for analyzing bidding strategies of generators in a deregulated energy marketplace with Pool Bilateral contracts so as to maximize their net profits. A new methodology to build bidding methodology for generators participating in oligopoly electricity market has been proposed in this paper. It is assumed that each generator bids a supply function. This methodology finds out the coefficients in the supply function of generators in order to maximize benefits in an environment of competing rival bidders. A natural choice for developing strategies is Nash Equilibrium (NE) model incorporating mixed strategies, for solving the bidding problem of electrical market. Associated optimal profits are evaluated for a combination of set of pure strategies of bidding of generators, and payoff matrix has been constructed. The optimal payoff is calculated by using NE. An attempt has also been made to minimize the gap between the optimal payoff and the payoff obtained by a possible mixed strategies combination. The algorithm is coded in MATLAB. A numerical example is used to illustrate the essential features of the approach and the results are proved to be the optimal values.

  13. Three Essays on Renewable Energy Policy and its Effects on Fossil Fuel Generation in Electricity Markets

    NASA Astrophysics Data System (ADS)

    Bowen, Eric

    In this dissertation, I investigate the effectiveness of renewable policies and consider their impact on electricity markets. The common thread of this research is to understand how renewable policy incentivizes renewable generation and how the increasing share of generation from renewables affects generation from fossil fuels. This type of research is crucial for understanding whether policies to promote renewables are meeting their stated goals and what the unintended effects might be. To this end, I use econometric methods to examine how electricity markets are responding to an influx of renewable energy. My dissertation is composed of three interrelated essays. In Chapter 1, I employ recent scholarship in spatial econometrics to assess the spatial dependence of Renewable Portfolio Standards (RPS), a prominent state-based renewable incentive. In Chapter 2, I explore the impact of the rapid rise in renewable generation on short-run generation from fossil fuels. And in Chapter 3, I assess the impact of renewable penetration on coal plant retirement decisions.

  14. Environmental benchmarking of the largest fossil-fueled electricity generating plants in the U.S

    NASA Astrophysics Data System (ADS)

    Sarkis, Joseph

    2004-02-01

    Environmental management, to be effective, requires performance evaluation and process improvement. This is especially the case in fossil-fueled electricity generating plants. Although eco-efficient management of these types of organizations are critical to local, national and global environmental issues, few studies have focused on performance measurement and eco-efficiency improvements in this industry. This study evaluates the eco-efficiencies of the top 100 major U.S. fossil-fueled electricity generating plants from 1998 data. Using a multi-criteria non-parametric productivity model (data envelopment analysis) efficiency scores are determined. These efficiency scores are treated by a clustering method in identifying benchmarks for improving poorly performing plants. Efficiency measures are based on three resource input measures including boiler generating capacity, total fuel heat used, and total generator capacity, and four output measures including actual energy generated, SO2, NOx, and CO2 emissions. The purpose of this paper is two-fold, to introduce the methodology"s application to eco-efficiency performance measurement and show some characteristics of the benchmarked plants and groups.

  15. Crew Factors in Flight Operations 7: Psychophysiological Responses to Overnight Cargo Operations

    NASA Technical Reports Server (NTRS)

    Gander, Philippa H.; Gregory, Kevin B.; Connell, Linda J.; Miller, Donna L.; Graeber, R. Curtis; Rosekind, Mark R.

    1996-01-01

    To document the psychophysiological effects of flying overnight cargo operations, 41 B-727 crew members (average age 38 yr) were monitored before, during, and after one of two typical 8-day trip patterns. During daytime layovers, the average sleep episode was 3 hr (41%) shorter than nighttime sleeps and was rated as lighter, less restorative, and poorer overall. Sleep was frequently split into several episodes and totaled 1.2 hr less per 24 hr than on pretrip days. Each trip pattern included a night off, which was an effective countermeasure against the accumulating sleep debt. The organization of sleep during daytime layovers reflected the interaction of duty timing with circadian physiology. The circadian temperature rhythm did not adapt completely to the inverted wake-rest schedule on duty days, being delayed by about 3 hr. Highest subjective fatigue and lowest activation occurred around the time of the temperature minimum. On duty days, reports of headaches increased by 400%, of congested nose by 200%, and of burning eyes by 900%. Crew members also reported eating more snacks. Compared with daytime short-haul air-transport operations, the overnight cargo trips included fewer duty and flight hours, and had longer layovers. Overnight cargo crews also averaged 5.4 yr younger than their daytime short-haul counterparts. On trips, both groups lost a comparable amount of sleep per 24 hr, but the overnight cargo crews had shorter individual sleep episodes and more broken sleep. These data clearly demonstrate that overnight cargo operations, like other night work, involve physiological disruption not found in comparable daytime operations.

  16. The energetic implications of curtailing versus storing wind- and solar-generated electricity

    NASA Astrophysics Data System (ADS)

    Barnhart, C. J.; Dale, M.; Brandt, A. R.; Benson, S. M.

    2013-12-01

    Rapid deployment of power generation technologies harnessing wind and solar resources continues to reduce the carbon intensity of the power grid. But as these technologies comprise a larger fraction of power supply, their variable, weather-dependent nature poses challenges to power grid operation. Today, during times of power oversupply or unfavorable market conditions, power grid operators curtail these resources. Rates of curtailment are expected to increase with increased renewable electricity production. That is unless technologies are implemented that can provide grid flexibility to balance power supply with power demand. Curtailment is an obvious forfeiture of energy and it decreases the profitability of electricity from curtailed generators. What are less obvious are the energetic costs for technologies that provide grid flexibility. We present a theoretical framework to calculate how storage affects the energy return on energy investment (EROI) ratios of wind and solar resources. Our methods identify conditions under which it is more energetically favorable to store energy than it is to simply curtail electricity production. Electrochemically based storage technologies result in much smaller EROI ratios than large-scale geologically based storage technologies like compressed air energy storage (CAES) and pumped hydroelectric storage (PHS). All storage technologies paired with solar photovoltaic (PV) generation yield EROI ratios that are greater than curtailment. Due to their low energy stored on electrical energy invested (ESOIe) ratios, conventional battery technologies reduce the EROI ratios of wind generation below curtailment EROI ratios. To yield a greater net energy return than curtailment, battery storage technologies paired with wind generation need an ESOIe>80. We identify improvements in cycle life as the most feasible way to increase battery ESOIe. Depending upon the battery's embodied energy requirement, an increase of cycle life to 10

  17. A methodology to identify stranded generation facilities and estimate stranded costs for Louisiana's electric utility industry

    NASA Astrophysics Data System (ADS)

    Cope, Robert Frank, III

    1998-12-01

    The electric utility industry in the United States is currently experiencing a new and different type of growing pain. It is the pain of having to restructure itself into a competitive business. Many industry experts are trying to explain how the nation as a whole, as well as individual states, will implement restructuring and handle its numerous "transition problems." One significant transition problem for federal and state regulators rests with determining a utility's stranded costs. Stranded generation facilities are assets which would be uneconomic in a competitive environment or costs for assets whose regulated book value is greater than market value. At issue is the methodology which will be used to estimate stranded costs. The two primary methods are known as "Top-Down" and "Bottom-Up." The "Top-Down" approach simply determines the present value of the losses in revenue as the market price for electricity changes over a period of time into the future. The problem with this approach is that it does not take into account technical issues associated with the generation and wheeling of electricity. The "Bottom-Up" approach computes the present value of specific strandable generation facilities and compares the resulting valuations with their historical costs. It is regarded as a detailed and difficult, but more precise, approach to identifying stranded assets and their associated costs. This dissertation develops a "Bottom-Up" quantitative, optimization-based approach to electric power wheeling within the state of Louisiana. It optimally evaluates all production capabilities and coordinates the movement of bulk power through transmission interconnections of competing companies in and around the state. Sensitivity analysis to this approach is performed by varying seasonal consumer demand, electric power imports, and transmission inter-connection cost parameters. Generation facility economic dispatch and transmission interconnection bulk power transfers, specific

  18. Temporal evolution of the sulphur oxides emissions from the Greek electricity generation sector.

    PubMed

    Kaldellis, J K; Voutsinas, M; Paliatsos, A G; Koronakis, P S

    2004-12-01

    The Greek electricity production sector is based--as far back as the early 60s--on the usage of local lignite and imported heavy-oil. Hence the electricity production process is assumed responsible for a significant contribution to air pollution, including 80% of the national sulphur dioxide emissions. In this context, an extensive and thorough analysis is carried out concerning the SO2 effluents coming from the electricity generation sector during the 1995-2002 period. For this purpose, the available long-term official measurements are taken into consideration and analysed in depth. According to this analysis, the SO2 emissions factor ratio between Southern Greece and Northern Greece lignite fired stations is in the order of 25:1. Additionally, one may definitely state that there is a considerable surcharge of sulphur oxides released by the Greek electricity production system, which although showing a fairly decreasing tendency, is still above the 8.5gr kWh(-1) consumed. Finally, the positive contribution of the natural gas, gradually replacing other fuels, and the operation of a new desulphurisation unit in S. Greece are clearly counterbalanced by the significant and constant annual electricity consumption amplification of the last decade. PMID:15691198

  19. An assessment of ocean thermal energy conversion as an advanced electric generation methodology

    SciTech Connect

    Heydt, G.T. . School of Electrical Engineering)

    1993-03-01

    Ocean thermal energy conversion (OTEC) is a process that employs the temperature difference between surface and deep ocean water to alternately evaporate and condense a working fluid. In the open-cycle OTEC configuration, the working fluid is seawater. In the closed-cycle configuration, a working fluid such as propane is used. In this paper, OTEC is assessed for its practical merits for electric power generation. The process is not new--and its history is reviewed. Because the OTEC principle operates under a small net temperature difference regime, rather large amounts of seawater and working fluid are required. The energy requirements for pumping these fluids may be greater than the energy recovered from the OTEC engine itself. The concept of net power production is discussed. The components of a typical OTEC plant are discussed with emphasis on the evaporator heat exchanger. Operation of an OTEC electric generating station is discussed, including transient operation. Perhaps the most encouraging aspect of OTEC is the recent experiments and efforts at the Natural Energy Laboratory--Hawaii (NELH). The NELH work is summarized in the paper. Remarks are made on bottlenecks and the future of OTEC as an advanced electric generation methodology.

  20. An assessment of ocean thermal energy conversion as an advanced electric generation methodology

    NASA Astrophysics Data System (ADS)

    Heydt, Gerald T.

    1993-03-01

    Ocean thermal energy conversion (OTEC) is a process that employs the temperature difference between surface and deep ocean water to alternately evaporate and condense a working fluid. In the open-cycle OTEC configuration, the working fluid is seawater. In the closed-cycle configuration, a working fluid such as propane is used. In this paper, OTEC is assessed for its practical merits for electric power generation, and the history of the process is reviewed. Because the OTEC principle operates under a small net temperature difference regime, rather large amounts of seawater and working fluid are required. The energy requirements for pumping these fluids may be greater than the energy recovered from the OTEC engine itself. The concept of net power production is discussed. The components of a typical OTEC plant are discussed with emphasis on the evaporator heat exchanger. Operation of an OTEC electric generating station is discussed, including transient operation. Perhaps the most encouraging aspect of OTEC is the recent experiments and efforts at the Natural Energy Laboratory in Hawaii, which are discussed in the paper. Remarks are made on bottlenecks and the future of OTEC as an advanced electric generation methodology.

  1. Enhancing factors of electricity generation in a microbial fuel cell using Geobacter sulfurreducens.

    PubMed

    Kim, Mi-Sun; Cha, Jaehwan; Kim, Dong-Hoon

    2012-10-01

    In this study, we investigated various cultural and operational factors to enhance electricity generation in a microbial fuel cell (MFC) using Geobacter sulfurreducens. The pure culture of G. sulfurreducens was cultivated using various substrates including acetate, malate, succinate, and butyrate, with fumarate as an electron acceptor. Cell growth was observed only in acetate-fed medium, when the cell concentrations increased 4-fold for 3 days. A high acetate concentration suppressed electricity generation. As the acetate concentration was increased from 5 to 20 mM, the power density dropped from 16 to 13 mW/m2, whereas the coulombic efficiency (CE) declined by about half. The immobilization of G. sulfurreducens on the anode considerably reduced the enrichment period from 15 to 7 days. Using argon gas to create an anaerobic condition in the anode chamber led to increased pH, and electricity generation subsequently dropped. When the plain carbon paper cathode was replaced by Pt-coated carbon paper (0.5 mg Pt/cm2), the CE increased greatly from 39% to 83%.

  2. [Electricity generation from sweet potato fuel ethanol wastewater using microbial fuel cell technology].

    PubMed

    Cai, Xiao-Bo; Yang, Yi; Sun, Yan-Ping; Zhang, Liang; Xiao, Yao; Zhao, Hai

    2010-10-01

    Air cathode microbial fuel cell (MFC) were investigated for electricity production from sweet potato fuel ethanol wastewater containing 5000 mg/L of chemical oxygen demand (COD). Maximum power density of 334.1 mW/m2, coulombic efficiency (CE) of 10.1% and COD removal efficiency of 92.2% were approached. The effect of phosphate buffer solution (PBS) and COD concentration on the performance of MFC was further examined. The addition of PBS from 50 mmol/L to 200 mmol/L increased the maximum power density and CE by 33.4% and 26.0%, respectively. However, the COD removal efficiency was not relative to PBS concentration in the wastewater. When the COD increased from 625 mg/L to 10 000 mg/L, the maximum value of COD removal efficiency and the maximum power density were gained at the wastewater strength of 5 000 mg/L. But the CE ranged from 28.9% to 10.3% with a decreasing trend. These results demonstrate that sweet potato fuel ethanol wastewater can be used for electricity generation in MFC while at the same time achieving wastewater treatment. The increasing of PBS concentration can improve the power generation of MFC. The maximum power density of MFC increases with the rise of COD concentration, but the electricity generation will decrease for the acidification of high wastewater concentration.

  3. Energy Management Challenges and Opportunities with Increased Intermittent Renewable Generation on the California Electrical Grid

    NASA Astrophysics Data System (ADS)

    Eichman, Joshua David

    Renewable resources including wind, solar, geothermal, biomass, hydroelectric, wave and tidal, represent an opportunity for environmentally preferred generation of electricity that also increases energy security and independence. California is very proactive in encouraging the implementation of renewable energy in part through legislation like Assembly Bill 32 and the development and execution of Renewable Portfolio Standards (RPS); however renewable technologies are not without challenges. All renewable resources have some resource limitations, be that from location, capacity, cost or availability. Technologies like wind and solar are intermittent in nature but represent one of the most abundant resources for generating renewable electricity. If RPS goals are to be achieved high levels of intermittent renewables must be considered. This work explores the effects of high penetration of renewables on a grid system, with respect to resource availability and identifies the key challenges from the perspective of the grid to introducing these resources. The HiGRID tool was developed for this analysis because no other tool could explore grid operation, while maintaining system reliability, with a diverse set of renewable resources and a wide array of complementary technologies including: energy efficiency, demand response, energy storage technologies and electric transportation. This tool resolves the hourly operation of conventional generation resources (nuclear, coal, geothermal, natural gas and hydro). The resulting behavior from introducing additional renewable resources and the lifetime costs for each technology is analyzed.

  4. [Electricity generation of surplus sludge microbial fuel cells enhanced by additional enzyme].

    PubMed

    Yang, Hui; Liu, Zhi-Hu; Li, Xiao-Ming; Yang, Qi; Fang, Li; Huang, Hua-Jun; Zeng, Guang-Ming; Li, Shuo

    2012-01-01

    In this paper the feasibility of enhanced electricity generation of microbial fuel cell fed surplus sludge by additional enzymes (neutral protease and alpha-amylase) was discussed. The effect of dosage of additional enzyme on characteristics of electricity generation of the surplus sludge microbial fuel cell (SSMFC) and the reduction of surplus sludge were investigated. The results indicated that the maximum output power destiny of the group of experiment was higher than that of control under the same condition. Moreover, the maximum output power density, coulomb efficiency, efficiency of reducing TCOD, efficiency of reducing TSS and efficiency of reducing VSS reached up to 507 W x m(-2) (700 mW x m(-2)), 3.98% (5.11%), 88.31% (94.09%), 83.18% (98.02%) and 89.03% (98.80%) respectively for protease (alpha-amylase) at the dosage of 10 mg x g(-1). This study demonstrated that additional enzyme greatly enhanced the electricity generation of MFC with simultaneous accomplishments of sludge treatment, providing a novel approach for the practical application of microbial fuel cell.

  5. [Electricity generation using high concentration terephthalic acid solution by microbial fuel cell].

    PubMed

    Ye, Ye-Jie; Song, Tian-Shun; Xu, Yuan; Chen, Ying-Wen; Zhu, She-Min; Shen, Shu-Bao

    2009-04-15

    The high concentration terephthalic acid (TA) solution as the substrate of microbial fuel cell (MFC) was studied to generate electricity. The open circuit voltage was 0.54 V after inoculating for 210 h with anaerobic activated sludge, which proved that TA can be the substrate of microbial fuel cell to generate electricity. The influence of pH and substrate concentration on generating electricity was studied deeply. The voltage output of external resistance (R = 1,000 Omega) was the highest when pH was 8.0. It increased as the substrate concentration increasing and tended towards a maximum value. The maximum voltage output Umax was 0.5 V and Ks was 785.2 mg/L by Monod equation regression. When the substrate concentration (according to COD) was 4000 mg/L, the maximum power density was 96.3 mW/m2, coulomb efficiency was 2.66% and COD removal rate was 80.3%.

  6. Nanosecond pulsed electric field generators for the study of subcellular effects.

    PubMed

    Kolb, Juergen F; Kono, Susumu; Schoenbach, Karl H

    2006-04-01

    Modeling and experimental studies have shown that pulsed electric fields of nanosecond duration and megavolt per meter amplitude affect subcellular structures but do not lead to the formation of large pores in the outer membrane. This "intracellular electromanipulation" requires the use of pulse generators which provide extremely high power but low energy pulses. In this study, we describe the concept of the required pulsed power sources, their design, operation, and the necessary diagnostics. Two types of pulse generators based on the Blumlein line principle have been developed and are described here. One system is designed to treat a large number of cells in cuvettes holding volumes from 0.1 to 0.8 ml. Pulses of up to 40 kV amplitude, with a duration of 10 ns and a rise time close to 1 ns can be applied to the cuvette. For an electrode gap of 1 mm this voltage corresponds to an average electric field of 40 MV/m. The second system allows for real time observation of individual cells under a microscope. It generates pulses of 10-300 ns duration with a rise time of 3.5 ns and voltage amplitudes up to 1 kV. Connected to a microreactor with an electrode gap of 100 microm, electric fields up to 10 MV/m are applied.

  7. Impacts of demand response and renewable generation in electricity power market

    NASA Astrophysics Data System (ADS)

    Zhao, Zhechong

    This thesis presents the objective of the research which is to analyze the impacts of uncertain wind power and demand response on power systems operation and power market clearing. First, in order to effectively utilize available wind generation, it is usually given the highest priority by assigning zero or negative energy bidding prices when clearing the day-ahead electric power market. However, when congestion occurs, negative wind bidding prices would aggravate locational marginal prices (LMPs) to be negative in certain locations. A load shifting model is explored to alleviate possible congestions and enhance the utilization of wind generation, by shifting proper amount of load from peak hours to off peaks. The problem is to determine proper amount of load to be shifted, for enhancing the utilization of wind generation, alleviating transmission congestions, and making LMPs to be non-negative values. The second piece of work considered the price-based demand response (DR) program which is a mechanism for electricity consumers to dynamically manage their energy consumption in response to time-varying electricity prices. It encourages consumers to reduce their energy consumption when electricity prices are high, and thereby reduce the peak electricity demand and alleviate the pressure to power systems. However, it brings additional dynamics and new challenges on the real-time supply and demand balance. Specifically, price-sensitive DR load levels are constantly changing in response to dynamic real-time electricity prices, which will impact the economic dispatch (ED) schedule and in turn affect electricity market clearing prices. This thesis adopts two methods for examining the impacts of different DR price elasticity characteristics on the stability performance: a closed-loop iterative simulation method and a non-iterative method based on the contraction mapping theorem. This thesis also analyzes the financial stability of DR load consumers, by incorporating

  8. Staff Draft Report. Comparative Cost of California Central Station Electricity Generation Technologies.

    SciTech Connect

    Badr, Magdy; Benjamin, Richard

    2003-02-11

    This Energy Commission staff draft report presents preliminary levelized cost estimates for several generic central-station electricity generation technologies. California has traditionally adopted energy policies that balance the goals of supporting economic development, improving environmental quality and promoting resource diversity. In order to be effective, such policies must be based on comprehensive and timely gathering of information. With this goal in mind, the purpose of the report is to provide comparative levelized cost estimates for a set of renewable (e.g., solar) and nonrenewable (e.g., natural gas-fired) central-station electricity generation resources, based on each technology's operation and capital cost. Decision-makers and others can use this information to compare the generic cost to build specific technology. These costs are not site specific. If a developer builds a specific power plant at a specific location, the cost of siting that plant at that specific location must be considered. The Energy Commission staff also identifies the type of fuel used by each technology and a description of the manner in which the technology operates in the generation system. The target audiences of this report are both policy-makers and anyone wishing to understand some of the fundamental attributes that are generally considered when evaluating the cost of building and operating different electricity generation technology resources. These costs do not reflect the total cost to consumers of adding these technologies to a resources portfolio. These technology characterizations do not capture all of the system, environmental or other relevant attributes that would typically be needed by a portfolio manager to conduct a comprehensive ''comparative value analysis''. A portfolio analysis will vary depending on the particular criteria and measurement goals of each study. For example, some form of firm capacity is typically needed with wind generation to support

  9. Impacts of Air Pollution on Solar Photovoltaic Electricity Generation in China

    NASA Astrophysics Data System (ADS)

    Li, X.; Mauzerall, D. L.; Wagner, F.; Yang, J.

    2015-12-01

    Solar photovoltaic (PV) electricity generation has been expanding rapidly in China with total capacity quadrupled from 8 to 32 GW between 2012 and 2014. Studies find that China has the potential to increase solar PV in total energy generation up towards 10% (about 300 GW in total capacity) by 2030. However, severe air pollution in China reduces the productivity of solar PV panels by scattering and absorbing sunlight before it reaches the surface. In this study, we first calculate the surface radiative forcing of anthropogenic aerosols (considering only the direct effect) over China from 2003 to 2013 using the Monitoring Atmospheric Composition and Climate (MACC) reanalysis dataset constrained by satellite derived greenhouse gas, reactive gases and aerosols. Our results indicate that, from 2003-2013, the attenuation of sunlight by aerosols over Eastern China averaged about -25 W m-2 compared with the global mean effect of -4.4 W m-2. The largest attenuation is found in Northern China in spring when mean attenuation reached as high as -57 W m-2. This attenuation reduced surface radiative flux by approximately 10%. In Southeastern China, maximum attenuation also occurred in spring, but had a smaller -40 W m-2 monthly mean. Western China is pristine in comparison, featuring no more than a -15 W m-2 monthly mean attenuation. These results imply a potentially large benefit for solar PV efficiency of improving air quality in eastern regions of China. We estimate that, if anthropogenic aerosols were entirely removed in China, solar PV generation would (1) increase 4.5-6.7% (varying among provinces) in Northeastern China where there is abundant solar resource,; (2) reduce the payback period by up to 1 year, increasing investment incentives particularly for distributed PV in Eastern China; and (3) increase total electricity generation in China in 2030 by up to 34 TWh/yr if the total capacity reaches 480 GW, equivalent to one-third of current annual electricity generation

  10. Field monitoring of condition of large electric generators. (Latest citations from the EI Compendex plus database). Published Search

    SciTech Connect

    Not Available

    1993-08-01

    The bibliography contains citations concerning monitoring techniques to determine the condition of large electric generators. Electric generators are limited to turbine generators, variously called hydroturbines, turbogenerators and turbosets. Wind turbines and magnetohydrodynamics are not included in this bibliography. Techniques for condition monitoring include noise analysis and acoustic monitoring, vibration and misalignment measurements, bearing oil analyses, and transient torsional changes affecting shafts and rotors. (Contains a minimum of 178 citations and includes a subject term index and title list.)

  11. Project Overview: United Parcel Service's Second-Generation Hybrid-Electric Delivery Vans (Fact Sheet)

    SciTech Connect

    Not Available

    2011-11-01

    This fact sheet describes UPS second generation hybrid-electric delivery vehicles as compared to conventional delivery vehicles. Medium-duty commercial vehicles such as moving trucks, beverage-delivery trucks, and package-delivery vans consume almost 2,000 gal of fuel per year on average. United Parcel Service (UPS) operates hybrid-electric package-delivery vans to reduce the fuel use and emissions of its fleet. In 2008, the National Renewable Energy Laboratory's (NREL's) Fleet Test and Evaluation Team evaluated the first generation of UPS' hybrid delivery vans. These hybrid vans demonstrated 29%-37% higher fuel economy than comparable conventional diesel vans, which contributed to UPS' decision to add second-generation hybrid vans to its fleet. The Fleet Test and Evaluation Team is now evaluating the 18-month, in-service performance of 11 second-generation hybrid vans and 11 comparable conventional diesel vans operated by UPS in Minneapolis, Minnesota. The evaluation also includes testing fuel economy and emissions at NREL's Renewable Fuels and Lubricants (ReFUEL) Laboratory and comparing diesel particulate filter (DPF) regeneration. In addition, a followup evaluation of UPS' first-generation hybrid vans will show how those vehicles performed over three years of operation. One goal of this project is to provide a consistent comparison of fuel economy and operating costs between the second-generation hybrid vans and comparable conventional vans. Additional goals include quantifying the effects of hybridization on DPF regeneration and helping UPS select delivery routes for its hybrid vans that maximize the benefits of hybrid technology. This document introduces the UPS second-generation hybrid evaluation project. Final results will be available in mid-2012.

  12. The impacts of renewable energy policies on renewable energy sources for electricity generating capacity

    NASA Astrophysics Data System (ADS)

    Koo, Bryan Bonsuk

    Electricity generation from non-hydro renewable sources has increased rapidly in the last decade. For example, Renewable Energy Sources for Electricity (RES-E) generating capacity in the U.S. almost doubled for the last three year from 2009 to 2012. Multiple papers point out that RES-E policies implemented by state governments play a crucial role in increasing RES-E generation or capacity. This study examines the effects of state RES-E policies on state RES-E generating capacity, using a fixed effects model. The research employs panel data from the 50 states and the District of Columbia, for the period 1990 to 2011, and uses a two-stage approach to control endogeneity embedded in the policies adopted by state governments, and a Prais-Winsten estimator to fix any autocorrelation in the panel data. The analysis finds that Renewable Portfolio Standards (RPS) and Net-metering are significantly and positively associated with RES-E generating capacity, but neither Public Benefit Funds nor the Mandatory Green Power Option has a statistically significant relation to RES-E generating capacity. Results of the two-stage model are quite different from models which do not employ predicted policy variables. Analysis using non-predicted variables finds that RPS and Net-metering policy are statistically insignificant and negatively associated with RES-E generating capacity. On the other hand, Green Energy Purchasing policy is insignificant in the two-stage model, but significant in the model without predicted values.

  13. The role of cellular coupling in the spontaneous generation of electrical activity in uterine tissue.

    PubMed

    Xu, Jinshan; Menon, Shakti N; Singh, Rajeev; Garnier, Nicolas B; Sinha, Sitabhra; Pumir, Alain

    2015-01-01

    The spontaneous emergence of contraction-inducing electrical activity in the uterus at the beginning of labor remains poorly understood, partly due to the seemingly contradictory observation that isolated uterine cells are not spontaneously active. It is known, however, that the expression of gap junctions increases dramatically in the approach to parturition, by more than one order of magnitude, which results in a significant increase in inter-cellular electrical coupling. In this paper, we build upon previous studies of the activity of electrically excitable smooth muscle cells (myocytes) and investigate the mechanism through which the coupling of these cells to electrically passive cells results in the generation of spontaneous activity in the uterus. Using a recently developed, realistic model of uterine muscle cell dynamics, we investigate a system consisting of a myocyte coupled to passive cells. We then extend our analysis to a simple two-dimensional lattice model of the tissue, with each myocyte being coupled to its neighbors, as well as to a random number of passive cells. We observe that different dynamical regimes can be observed over a range of gap junction conductances: at low coupling strength, corresponding to values measured long before delivery, the activity is confined to cell clusters, while the activity for high coupling, compatible with values measured shortly before delivery, may spread across the entire tissue. Additionally, we find that the system supports the spontaneous generation of spiral wave activity. Our results are both qualitatively and quantitatively consistent with observations from in vitro experiments. In particular, we demonstrate that the increase in inter-cellular electrical coupling observed experimentally strongly facilitates the appearance of spontaneous action potentials that may eventually lead to parturition. PMID:25793276

  14. Evaluating the Climate Effects of Natural Gas Versus Coal Electricity Generation

    NASA Astrophysics Data System (ADS)

    Zhang, X.; Myhrvold, N. P.; Caldeira, K.

    2014-12-01

    Assessing potential climate effects of fossil-fuel electricity generations, especially natural gas versus coal electricity generation is complicated by the large number of factors reported in life cycle assessment studies, compounded by the large number of proposed climate metrics. Thus, there is a need to identify the key factors affecting the climate effects of fossil-fuel electricity generations (especially natural gas and coal based electricity production), and to present these climate effects in as clear and transparent a way as possible. Here, we identify power plant efficiencies and methane emission rates as the factors that explain most of the variance in greenhouse gas emissions by natural gas and coal power plants. Thus, we focus on the roles of these factors in determining the relative merit of natural gas and coal power plants. We develop a simple model with estimating CH4 and CO2 emissions from natural gas and coal power plants and resulting climate effects. Simple underlying physical changes can be obscured by abstract evaluation metrics, thus we base our discussion on temperature changes over time. We find that, during the period of plant operation, if there is substantial natural gas leakage, natural gas plants can produce greater near-term warming than a coal plant with the same power output. However, if leakage rates can be made to be low and efficiency high, natural gas plants can produce some reduction in near-term warming. After several centuries of continuous use, natural gas power plants produce substantial warming, but in most cases substantially less warming than would occur with coal plants.

  15. Electricity generation from an inorganic sulfur compound containing mining wastewater by acidophilic microorganisms.

    PubMed

    Ni, Gaofeng; Christel, Stephan; Roman, Pawel; Wong, Zhen Lim; Bijmans, Martijn F M; Dopson, Mark

    2016-09-01

    Sulfide mineral processing often produces large quantities of wastewaters containing acid-generating inorganic sulfur compounds. If released untreated, these wastewaters can cause catastrophic environmental damage. In this study, microbial fuel cells were inoculated with acidophilic microorganisms to investigate whether inorganic sulfur compound oxidation can generate an electrical current. Cyclic voltammetry suggested that acidophilic microorganisms mediated electron transfer to the anode, and that electricity generation was catalyzed by microorganisms. A cation exchange membrane microbial fuel cell, fed with artificial wastewater containing tetrathionate as electron donor, reached a maximum whole cell voltage of 72 ± 9 mV. Stepwise replacement of the artificial anolyte with real mining process wastewater had no adverse effect on bioelectrochemical performance and generated a maximum voltage of 105 ± 42 mV. 16S rRNA gene sequencing of the microbial consortia resulted in sequences that aligned within the genera Thermoplasma, Ferroplasma, Leptospirillum, Sulfobacillus and Acidithiobacillus. This study opens up possibilities to bioremediate mining wastewater using microbial fuel cell technology.

  16. Kinetics of substrate degradation and electricity generation in anodic denitrification microbial fuel cell (AD-MFC).

    PubMed

    Zhang, Jiqiang; Zheng, Ping; Zhang, Meng; Chen, Hui; Chen, Tingting; Xie, Zuofu; Cai, Jing; Abbas, Ghulam

    2013-12-01

    Effect of substrate concentration on substrate degradation and electricity generation in anodic denitrification microbial fuel cell (AD-MFC) was investigated over a broad range of substrate concentrations. Substrate degradation rates and power generation could be promoted with increasing substrate concentration in a certain range, but both of them would be inhibited at high substrate concentrations. Maximum denitrification rate of 1.26 ± 0.01 kg NO(-)-N/m(3)d and maximum output voltage of 1016.75 ± 4.74 mV could be achieved when initial NO3(-)-N concentration was 1999.95 ± 2.86 mg/L. Based on Han-Levenspiel model, kinetics of substrate degradation and power generation in the AD-MFC were established. According to the kinetic model, the half-saturation coefficient and the critical inhibitory concentration for nitrate were more than 200 and 4300 mg/L, respectively. The results demonstrated that AD-MFC was capable of treating nitrate-containing wastewater and generating electricity simultaneously, and tolerant to high strength nitrate-containing wastewater.

  17. Impact of the proposed energy tax on nuclear electric generating technologies

    SciTech Connect

    Edmunds, T.A.; Lamont, A.D.; Pasternak, A.D.; Rousseau, W.F.; Walter, C.E.

    1993-05-01

    The President`s new economic initiatives include an energy tax that will affect the costs of power from most electric generating technologies. The tax on nuclear power could be applied in a number of different ways at several different points in the fuel cycle. These different approaches could have different effects on the generation costs and benefits of advanced reactors. The Office of Nuclear Energy has developed models for assessing the costs and benefits of advanced reactor cycles which must be updated to take into account the impacts of the proposed tax. This report has been prepared to assess the spectrum of impacts of the energy tax on nuclear power and can be used in updating the Office`s economic models. This study was conducted in the following steps. First, the most authoritative statement of the proposed tax available at this time was obtained. Then the impacts of the proposed tax on the costs of nuclear and fossil fueled generation were compared. Finally several other possible approaches to taxing nuclear energy were evaluated. The cost impact on several advanced nuclear technologies and a current light water technology were computed. Finally, the rationale for the energy tax as applied to various electric generating methods was examined.

  18. Electricity generation from an inorganic sulfur compound containing mining wastewater by acidophilic microorganisms.

    PubMed

    Ni, Gaofeng; Christel, Stephan; Roman, Pawel; Wong, Zhen Lim; Bijmans, Martijn F M; Dopson, Mark

    2016-09-01

    Sulfide mineral processing often produces large quantities of wastewaters containing acid-generating inorganic sulfur compounds. If released untreated, these wastewaters can cause catastrophic environmental damage. In this study, microbial fuel cells were inoculated with acidophilic microorganisms to investigate whether inorganic sulfur compound oxidation can generate an electrical current. Cyclic voltammetry suggested that acidophilic microorganisms mediated electron transfer to the anode, and that electricity generation was catalyzed by microorganisms. A cation exchange membrane microbial fuel cell, fed with artificial wastewater containing tetrathionate as electron donor, reached a maximum whole cell voltage of 72 ± 9 mV. Stepwise replacement of the artificial anolyte with real mining process wastewater had no adverse effect on bioelectrochemical performance and generated a maximum voltage of 105 ± 42 mV. 16S rRNA gene sequencing of the microbial consortia resulted in sequences that aligned within the genera Thermoplasma, Ferroplasma, Leptospirillum, Sulfobacillus and Acidithiobacillus. This study opens up possibilities to bioremediate mining wastewater using microbial fuel cell technology. PMID:27155452

  19. Overnight Science.

    ERIC Educational Resources Information Center

    Smith, Nancy N.; Stahl, Robert J.

    1981-01-01

    Outlines objectives for an elementary science camping program and summarizes general operational procedures. Campsite activities related to such topics as microorganisms, eye and sight, nature trails, bees, carpentry, and astronomy are described. (DS)

  20. Co-benefits and trade-offs between future electricity generation and water use on a global scale

    NASA Astrophysics Data System (ADS)

    Ando, N.; Yoshikawa, S.; Kanae, S.

    2015-12-01

    Water is essential to electricity generation. Power plant cooling water is responsible for 40-50% of total freshwater withdrawals in Europe (Rübbelke et al., 2011) and the United States (Kenny et al., 2009). In accordance with growing demands for electricity generation, water demands could be increased. There is concern that the water demands for electricity generation could compete with other major water users. Additionally, many countries are required reviewing energy policies to mitigate climate change. Thermal power replaced low carbon power like renewable energy, nuclear power, Carbon Capture and Storage as a mitigation technology. However, influences of such climate change mitigation technologies on water demands are still uncertain. In this study, we calculated freshwater demands for electricity generation by using the data set of future electricity generation in the twenty-first century which estimated by the Asia-Pacific Integrated Model, and assessed the overall effects of electricity generation on water demands under the Shared Socio-Economic Pathways and the Representative Concentration Pathways which were adopted by IPCC AR5. Water demands for electricity generation depends on cooling types, such as once-through cooling and recirculating cooling. We also took into account cooling system pathways. The result might be useful for deciding energy policies which aim for reduction of water demands, especially in regions experiencing water scarcity.

  1. Design and realization of a 300 W fuel cell generator on an electric bicycle

    NASA Astrophysics Data System (ADS)

    Cardinali, Luciano; Santomassimo, Saverio; Stefanoni, Marco

    At ENEA Casaccia Research Center (Rome, Italy) a 300 W NUVERA fuel cell stack has been utilized for the construction of a range extender generator on a commercial electric bicycle. The generator is fully automated with a programmable logic controller (PLC) safely operating start-up, shut-down and emergencies; a volumetric compressor supplies air to the cathode, a dc/dc converter transfers energy from the stack to the battery. All ancillary equipment are commercial; only the cell voltage sensors have been developed in order to obtain miniaturized and low consumption components. With this generator the bicycle nominal range of 25 km (utilizing only the Ni-Mh battery) is extended to over 120 km, by installing a 200 bar, 5 l bottle of hydrogen.

  2. Potential Impacts of Plug-in Hybrid Electric Vehicles on Regional Power Generation

    SciTech Connect

    Hadley, Stanton W; Tsvetkova, Alexandra A

    2008-01-01

    Plug-in hybrid electric vehicles (PHEVs) are being developed around the world, with much work aiming to optimize engine and battery for efficient operation, both during discharge and when grid electricity is available for recharging. However, the general expectation has been that the grid will not be greatly affected by the use of PHEVs because the recharging will occur during off-peak hours, or the number of vehicles will grow slowly enough so that capacity planning will respond adequately. This expectation does not consider that drivers will control the timing of recharging, and their inclination will be to plug in when convenient, rather than when utilities would prefer. It is important to understand the ramifications of adding load from PHEVs onto the grid. Depending on when and where the vehicles are plugged in, they could cause local or regional constraints on the grid. They could require the addition of new electric capacity and increase the utilization of existing capacity. Usage patterns of local distribution grids will change, and some lines or substations may become overloaded sooner than expected. Furthermore, the type of generation used to meet the demand for recharging PHEVs will depend on the region of the country and the timing of recharging. This paper analyzes the potential impacts of PHEVs on electricity demand, supply, generation structure, prices, and associated emission levels in 2020 and 2030 in 13 regions specified by the North American Electric Reliability Corporation (NERC) and the U.S. Department of Energy's (DOE's) Energy Information Administration (EIA), and on which the data and analysis in EIA's Annual Energy Outlook 2007 are based (Figure ES-1). The estimates of power plant supplies and regional hourly electricity demand come from publicly available sources from EIA and the Federal Energy Regulatory Commission. Electricity requirements for PHEVs are based on analysis from the Electric Power Research Institute, with an optimistic

  3. Intake-to-delivered-energy ratios for central station and distributed electricity generation in California

    NASA Astrophysics Data System (ADS)

    Heath, Garvin A.; Nazaroff, William W.

    In previous work, we showed that the intake fraction (iF) for nonreactive primary air pollutants was 20 times higher in central tendency for small-scale, urban-sited distributed electricity generation (DG) sources than for large-scale, central station (CS) power plants in California [Heath, G.A., Granvold, P.W., Hoats, A.S., Nazaroff, W.W., 2006. Intake fraction assessment of the air pollutant exposure implications of a shift toward distributed electricity generation. Atmospheric Environment 40, 7164-7177]. The present paper builds on that study, exploring pollutant- and technology-specific aspects of population inhalation exposure from electricity generation. We compare California's existing CS-based system to one that is more reliant on DG units sited in urban areas. We use Gaussian plume modeling and a GIS-based exposure analysis to assess 25 existing CSs and 11 DG sources hypothetically located in the downtowns of California's most populous cities. We consider population intake of three pollutants—PM 2.5, NO x and formaldehyde—directly emitted by five DG technologies—natural gas (NG)-fired turbines, NG internal combustion engines (ICE), NG microturbines, diesel ICEs, and fuel cells with on-site NG reformers. We also consider intake of these pollutants from existing CS facilities, most of which use large NG turbines, as well as from hypothetical facilities located at these same sites but meeting California's best-available control technology standards. After systematically exploring the sensitivity of iF to pollutant decay rate, the iFs for each of the three pollutants for all DG and CS cases are estimated. To efficiently compare the pollutant- and technology-specific exposure potential on an appropriate common basis, a new metric is introduced and evaluated: the intake-to-delivered-energy ratio (IDER). The IDER expresses the mass of pollutant inhaled by an exposed population owing to emissions from an electricity generation unit per quantity of electric

  4. Electrical control of second-harmonic generation in a WSe2 monolayer transistor

    NASA Astrophysics Data System (ADS)

    Seyler, Kyle L.; Schaibley, John R.; Gong, Pu; Rivera, Pasqual; Jones, Aaron M.; Wu, Sanfeng; Yan, Jiaqiang; Mandrus, David G.; Yao, Wang; Xu, Xiaodong

    2015-05-01

    Nonlinear optical frequency conversion, in which optical fields interact with a nonlinear medium to produce new field frequencies, is ubiquitous in modern photonic systems. However, the nonlinear electric susceptibilities that give rise to such phenomena are often challenging to tune in a given material and, so far, dynamical control of optical nonlinearities remains confined to research laboratories as a spectroscopic tool. Here, we report a mechanism to electrically control second-order optical nonlinearities in monolayer WSe2, an atomically thin semiconductor. We show that the intensity of second-harmonic generation at the A-exciton resonance is tunable by over an order of magnitude at low temperature and nearly a factor of four at room temperature through electrostatic doping in a field-effect transistor. Such tunability arises from the strong exciton charging effects in monolayer semiconductors, which allow for exceptional control over the oscillator strengths at the exciton and trion resonances. The exciton-enhanced second-harmonic generation is counter-circularly polarized to the excitation laser due to the combination of the two-photon and one-photon valley selection rules, which have opposite helicity in the monolayer. Our study paves the way towards a new platform for chip-scale, electrically tunable nonlinear optical devices based on two-dimensional semiconductors.

  5. GENERATION OF ELECTRIC CURRENTS IN THE CHROMOSPHERE VIA NEUTRAL-ION DRAG

    SciTech Connect

    Krasnoselskikh, V.; Vekstein, G.; Hudson, H. S.; Bale, S. D.; Abbett, W. P.

    2010-12-01

    We consider the generation of electric currents in the solar chromosphere where the ionization level is typically low. We show that ambient electrons become magnetized even for weak magnetic fields (30 G); that is, their gyrofrequency becomes larger than the collision frequency while ion motions continue to be dominated by ion-neutral collisions. Under such conditions, ions are dragged by neutrals, and the magnetic field acts as if it is frozen-in to the dynamics of the neutral gas. However, magnetized electrons drift under the action of the electric and magnetic fields induced in the reference frame of ions moving with the neutral gas. We find that this relative motion of electrons and ions results in the generation of quite intense electric currents. The dissipation of these currents leads to resistive electron heating and efficient gas ionization. Ionization by electron-neutral impact does not alter the dynamics of the heavy particles; thus, the gas turbulent motions continue even when the plasma becomes fully ionized, and resistive dissipation continues to heat electrons and ions. This heating process is so efficient that it can result in typical temperature increases with altitude as large as 0.1-0.3 eV km{sup -1}. We conclude that this process can play a major role in the heating of the chromosphere and corona.

  6. Next Generation of Renewable Electricity Policy: How Rapid Change is Breaking Down Conventional Policy Categories

    SciTech Connect

    Couture, T. D.; Jacobs, D.; Rickerson, W.; Healey, V.

    2015-02-01

    A number of policies have been used historically in order to stimulate the growth of the renewable electricity sector. This paper examines four of these policy instruments: competitive tendering, sometimes called renewable electricity auctions, feed-in tariffs, net metering and net billing, and tradable renewable energy certificates. In recent years, however, a number of changes to both market circumstances and to policy priorities have resulted in numerous policy innovations, including the emergence of policy hybrids. With no common language for these evolving policy mechanisms, policymakers have generally continued to use the same traditional policy labels, occasionally generating confusion as many of these new policies no longer look, or act, like their traditional predecessors. In reviewing these changes, this paper makes two separate but related claims: first, policy labels themselves are breaking down and evolving. As a result, policy comparisons that rely on the conventional labels may no longer be appropriate, or advisable. Second, as policymakers continue to adapt, we are in effect witnessing the emergence of the next generation of renewable electricity policies, a change that could have significant impacts on investment, as well as on market growth in both developed and developing countries.

  7. Spatially and Temporally Resolved Analysis of Environmental Trade-Offs in Electricity Generation.

    PubMed

    Peer, Rebecca A M; Garrison, Jared B; Timms, Craig P; Sanders, Kelly T

    2016-04-19

    The US power sector is a leading contributor of emissions that affect air quality and climate. It also requires a lot of water for cooling thermoelectric power plants. Although these impacts affect ecosystems and human health unevenly in space and time, there has been very little quantification of these environmental trade-offs on decision-relevant scales. This work quantifies hourly water consumption, emissions (i.e., carbon dioxide, nitrogen oxides, and sulfur oxides), and marginal heat rates for 252 electricity generating units (EGUs) in the Electric Reliability Council of Texas (ERCOT) region in 2011 using a unit commitment and dispatch model (UC&D). Annual, seasonal, and daily variations, as well as spatial variability are assessed. When normalized over the grid, hourly average emissions and water consumption intensities (i.e., output per MWh) are found to be highest when electricity demand is the lowest, as baseload EGUs tend to be the most water and emissions intensive. Results suggest that a large fraction of emissions and water consumption are caused by a small number of power plants, mainly baseload coal-fired generators. Replacing 8-10 existing power plants with modern natural gas combined cycle units would result in reductions of 19-29%, 51-55%, 60-62%, and 13-27% in CO2 emissions, NOx emissions, SOx emissions, and water consumption, respectively, across the ERCOT region for two different conversion scenarios. PMID:26967826

  8. Harmonization of initial estimates of shale gas life cycle greenhouse gas emissions for electric power generation.

    PubMed

    Heath, Garvin A; O'Donoughue, Patrick; Arent, Douglas J; Bazilian, Morgan

    2014-08-01

    Recent technological advances in the recovery of unconventional natural gas, particularly shale gas, have served to dramatically increase domestic production and reserve estimates for the United States and internationally. This trend has led to lowered prices and increased scrutiny on production practices. Questions have been raised as to how greenhouse gas (GHG) emissions from the life cycle of shale gas production and use compares with that of conventionally produced natural gas or other fuel sources such as coal. Recent literature has come to different conclusions on this point, largely due to differing assumptions, comparison baselines, and system boundaries. Through a meta-analytical procedure we call harmonization, we develop robust, analytically consistent, and updated comparisons of estimates of life cycle GHG emissions for electricity produced from shale gas, conventionally produced natural gas, and coal. On a per-unit electrical output basis, harmonization reveals that median estimates of GHG emissions from shale gas-generated electricity are similar to those for conventional natural gas, with both approximately half that of the central tendency of coal. Sensitivity analysis on the harmonized estimates indicates that assumptions regarding liquids unloading and estimated ultimate recovery (EUR) of wells have the greatest influence on life cycle GHG emissions, whereby shale gas life cycle GHG emissions could approach the range of best-performing coal-fired generation under certain scenarios. Despite clarification of published estimates through harmonization, these initial assessments should be confirmed through methane emissions measurements at components and in the atmosphere and through better characterization of EUR and practices.

  9. Photoelectrochemical generation of hydrogen and electricity from hydrazine hydrate using BiVO4 electrodes.

    PubMed

    Pilli, Satyananda Kishore; Summers, Kodi; Chidambaram, Dev

    2015-06-01

    This study demonstrates solar driven oxidation of hydrazine hydrate and the simultaneous production of hydrogen and electricity in photoelectrochemical cells and photofuel cells, respectively, using a visible light active molybdenum doped BiVO4 photoelectrode. The developed photoelectrodes exhibited tremendous efficiency towards anodic oxidation of hydrous hydrazine with continuous and stable hydrogen evolution at the Pt cathode under benign pH and zero bias conditions. Significantly, the photofuel cell containing hydrazine hydrate fuel has generated electricity with a high open circuit potential of 0.8 V. The presence of bicarbonate ions in the electrolyte has played a significant role in enhancing the kinetics of photoelectrochemical oxidation of hydrazine and improved the hydrogen and electricity generation efficiency thus avoiding the integration of an oxidation electrocatalyst. In addition, molybdenum doped BiVO4 as a possible photoelectrochemical hydrazine sensor has been investigated and the electrode photocurrent was found to be linearly dependent on the concentration of the hydrazine hydrate in the range of 20-90 mM with a correlation coefficient of 0.9936.

  10. Spatially and Temporally Resolved Analysis of Environmental Trade-Offs in Electricity Generation.

    PubMed

    Peer, Rebecca A M; Garrison, Jared B; Timms, Craig P; Sanders, Kelly T

    2016-04-19

    The US power sector is a leading contributor of emissions that affect air quality and climate. It also requires a lot of water for cooling thermoelectric power plants. Although these impacts affect ecosystems and human health unevenly in space and time, there has been very little quantification of these environmental trade-offs on decision-relevant scales. This work quantifies hourly water consumption, emissions (i.e., carbon dioxide, nitrogen oxides, and sulfur oxides), and marginal heat rates for 252 electricity generating units (EGUs) in the Electric Reliability Council of Texas (ERCOT) region in 2011 using a unit commitment and dispatch model (UC&D). Annual, seasonal, and daily variations, as well as spatial variability are assessed. When normalized over the grid, hourly average emissions and water consumption intensities (i.e., output per MWh) are found to be highest when electricity demand is the lowest, as baseload EGUs tend to be the most water and emissions intensive. Results suggest that a large fraction of emissions and water consumption are caused by a small number of power plants, mainly baseload coal-fired generators. Replacing 8-10 existing power plants with modern natural gas combined cycle units would result in reductions of 19-29%, 51-55%, 60-62%, and 13-27% in CO2 emissions, NOx emissions, SOx emissions, and water consumption, respectively, across the ERCOT region for two different conversion scenarios.

  11. Electrical control of second-harmonic generation in a WSe2 monolayer transistor

    SciTech Connect

    Seyler, Kyle L.; Schaibley, John R.; Gong, Pu; Rivera, Pasqual; Jones, Aaron M.; Wu, Sanfeng; Yan, Jiaqiang; Mandrus, David G.; Yao, Wang; Xu, Xiaodong

    2015-04-20

    Nonlinear optical frequency conversion, in which optical fields interact with a nonlinear medium to produce new field frequencies, is ubiquitous in modern photonic systems. However, the nonlinear electric susceptibilities that give rise to such phenomena are often challenging to tune in a given material and, so far, dynamical control of optical nonlinearities remains confined to research laboratories as a spectroscopic tool. In this paper, we report a mechanism to electrically control second-order optical nonlinearities in monolayer WSe2, an atomically thin semiconductor. We show that the intensity of second-harmonic generation at the A-exciton resonance is tunable by over an order of magnitude at low temperature and nearly a factor of four at room temperature through electrostatic doping in a field-effect transistor. Such tunability arises from the strong exciton charging effects in monolayer semiconductors, which allow for exceptional control over the oscillator strengths at the exciton and trion resonances. The exciton-enhanced second-harmonic generation is counter-circularly polarized to the excitation laser due to the combination of the two-photon and one-photon valley selection rules, which have opposite helicity in the monolayer. Finally, our study paves the way towards a new platform for chip-scale, electrically tunable nonlinear optical devices based on two-dimensional semiconductors.

  12. Electrical control of second-harmonic generation in a WSe2 monolayer transistor

    DOE PAGESBeta

    Seyler, Kyle L.; Schaibley, John R.; Gong, Pu; Rivera, Pasqual; Jones, Aaron M.; Wu, Sanfeng; Yan, Jiaqiang; Mandrus, David G.; Yao, Wang; Xu, Xiaodong

    2015-04-20

    Nonlinear optical frequency conversion, in which optical fields interact with a nonlinear medium to produce new field frequencies, is ubiquitous in modern photonic systems. However, the nonlinear electric susceptibilities that give rise to such phenomena are often challenging to tune in a given material and, so far, dynamical control of optical nonlinearities remains confined to research laboratories as a spectroscopic tool. In this paper, we report a mechanism to electrically control second-order optical nonlinearities in monolayer WSe2, an atomically thin semiconductor. We show that the intensity of second-harmonic generation at the A-exciton resonance is tunable by over an order ofmore » magnitude at low temperature and nearly a factor of four at room temperature through electrostatic doping in a field-effect transistor. Such tunability arises from the strong exciton charging effects in monolayer semiconductors, which allow for exceptional control over the oscillator strengths at the exciton and trion resonances. The exciton-enhanced second-harmonic generation is counter-circularly polarized to the excitation laser due to the combination of the two-photon and one-photon valley selection rules, which have opposite helicity in the monolayer. Finally, our study paves the way towards a new platform for chip-scale, electrically tunable nonlinear optical devices based on two-dimensional semiconductors.« less

  13. Simulation of an offshore wind farm using fluid power for centralized electricity generation

    NASA Astrophysics Data System (ADS)

    Jarquin-Laguna, A.

    2016-09-01

    A centralized approach for electricity generation within a wind farm is explored through the use of fluid power technology. This concept considers a new way of generation, collection and transmission of wind energy inside a wind farm, in which electrical conversion does not occur during any intermediate conversion step before the energy has reached the offshore central platform. A numerical model was developed to capture the relevant physics from the dynamic interaction between different turbines coupled to a common hydraulic network and controller. This paper presents two examples of the time-domain simulation results for an hypothetical hydraulic wind farm subject to turbulent wind conditions. The performance and operational parameters of individual turbines are compared with those of a reference wind farm with conventional technology turbines, using the same wind farm layout and environmental conditions. For the presented case study, results indicate that the individual wind turbines are able to operate within operational limits with the current pressure control concept. Despite the stochastic turbulent wind input and wake effects, the hydraulic wind farm is able to produce electricity with reasonable performance in both below and above rated conditions.

  14. Electric current generation by sulfur-reducing bacteria in microbial-anode fuel cell

    NASA Astrophysics Data System (ADS)

    Vasyliv, Oresta M.; Bilyy, Oleksandr I.; Ferensovych, Yaroslav P.; Hnatush, Svitlana O.

    2012-10-01

    Sulfur - reducing bacteria are a part of normal microflora of natural environment. Their main function is supporting of reductive stage of sulfur cycle by hydrogen sulfide production in the process of dissimilative sulfur-reduction. At the same time these bacteria completely oxidize organic compounds with CO2 and H2O formation. It was shown that they are able to generate electric current in the two chamber microbial-anode fuel cell (MAFC) by interaction between these two processes. Microbial-anode fuel cell on the basis of sulfur- and ferric iron-reducing Desulfuromonas acetoxidans bacteria has been constructed. It has been shown that the amount of electricity generation by investigated bacteria is influenced by the concentrations of carbon source (lactate) and ferric iron chloride. The maximal obtained electric current and potential difference between electrodes equaled respectively 0.28-0.29 mA and 0.19-0.2 V per 0.3 l of bacterial suspension with 0.4 g/l of initial biomass that was grown under the influence of 0.45 mM of FeCl3 and 3 g/l of sodium lactate as primal carbon source. It has also been shown that these bacteria are resistant to different concentrations of silver ions.

  15. Application of Bioelectrochemical Process (BES) for Electricity Generation and Sustainable Wastewater Treatment

    NASA Astrophysics Data System (ADS)

    Kim, Jung Rae

    Bioelectrochemical system such as microbial fuel cells (MFCs) and microbial electrolysis cell are an emerging technology which converts biodegradable organic matter to electrical energy or hydrogen using a biofilm on the electrode as the biocatalyst. It has recently been shown that waste-to-energy technology based on MFC can treat organic contaminant in domestic or industrial wastewater and simultaneously produce electricity. The maximum power density increased up to 1kW/m3 based on reactor volume. Bioelectrochemical systems may reduce the energy consumption for wastewater treatment by replacing energy intensive aeration of present treatment systems, while generate electrical energy from waste. In addition, the biomass production in MFCs has been reported to be 10-50% of conventional wastewater treatment, leading to reduce environmental impact and disposal costs. Various electrochemically active bacteria metabolize biodegradable organic compounds then discharge electrons to an extracellular electron acceptor for bacterial respiration. These bacteria also transfer electrons to electrodes by direct electron transfer, electron mediators or shuttles, and electrically conductive nanowires. Investigation of bacterial electron transport mechanisms may improve understanding of the biomaterial involved and metabolic pathways as well as improving power from MFCs. Biofuel cell systems require interdisciplinary research ranging from electrochemistry, microbiology, material science and surface chemistry to engineering such as reactor design, operation and modelling. Collaboration within each study and integration of systems might increase the performance and feasibility of BES process for sustainable energy.

  16. Accounting for climate and air quality damages in future U.S. electricity generation scenarios.

    PubMed

    Brown, Kristen E; Henze, Daven K; Milford, Jana B

    2013-04-01

    The EPA-MARKAL model of the U.S. electricity sector is used to examine how imposing emissions fees based on estimated health and environmental damages might change electricity generation. Fees are imposed on life-cycle emissions of SO(2), nitrogen oxides (NO(x)), particulate matter, and greenhouse gases (GHG) from 2015 through 2055. Changes in electricity production, fuel type, emissions controls, and emissions produced under various fees are examined. A shift in fuels used for electricity production results from $30/ton CO(2)-equivalent GHG fees or from criteria pollutant fees set at the higher-end of the range of published damage estimates, but not from criteria pollutant fees based on low or midrange damage estimates. With midrange criteria pollutant fees assessed, SO(2) and NOx emissions are lower than the business as usual case (by 52% and 10%, respectively), with larger differences in the western U.S. than in the eastern U.S. GHG emissions are not significantly impacted by midrange criteria pollutant fees alone; conversely, with only GHG fees, NO(x) emissions are reduced by up to 11%, yet SO(2) emissions are slightly higher than in the business as usual case. Therefore, fees on both GHG and criteria pollutants may be needed to achieve significant reductions in both sets of pollutants.

  17. Accounting for climate and air quality damages in future U.S. electricity generation scenarios.

    PubMed

    Brown, Kristen E; Henze, Daven K; Milford, Jana B

    2013-04-01

    The EPA-MARKAL model of the U.S. electricity sector is used to examine how imposing emissions fees based on estimated health and environmental damages might change electricity generation. Fees are imposed on life-cycle emissions of SO(2), nitrogen oxides (NO(x)), particulate matter, and greenhouse gases (GHG) from 2015 through 2055. Changes in electricity production, fuel type, emissions controls, and emissions produced under various fees are examined. A shift in fuels used for electricity production results from $30/ton CO(2)-equivalent GHG fees or from criteria pollutant fees set at the higher-end of the range of published damage estimates, but not from criteria pollutant fees based on low or midrange damage estimates. With midrange criteria pollutant fees assessed, SO(2) and NOx emissions are lower than the business as usual case (by 52% and 10%, respectively), with larger differences in the western U.S. than in the eastern U.S. GHG emissions are not significantly impacted by midrange criteria pollutant fees alone; conversely, with only GHG fees, NO(x) emissions are reduced by up to 11%, yet SO(2) emissions are slightly higher than in the business as usual case. Therefore, fees on both GHG and criteria pollutants may be needed to achieve significant reductions in both sets of pollutants. PMID:23465362

  18. New Technology for Microfabrication and Testing of a Thermoelectric Device for Generating Mobile Electrical Power

    NASA Technical Reports Server (NTRS)

    Prasad, Narasimha S.; Taylor, Patrick J.; Trivedi, Sudhir B.; Kutcher, Susan

    2012-01-01

    Thermoelectric (TE) power generation is an increasingly important power generation technology. Major advantages include: no moving parts, low-weight, modularity, covertness/silence, high power density, low amortized cost, and long service life with minimum or no required maintenance. Despite low efficiency of power generation, there are many specialized needs for electrical power that TE technologies can uniquely and successfully address. Recent advances in thermoelectric materials technology have rekindled acute interest in thermoelectric power generation. We have developed single crystalline n- and p- type PbTe crystals and are also, developing PbTe bulk nanocomposites using PbTe nano powders and emerging filed assisted sintering technology (FAST). We will discuss the materials requirements for efficient thermoelectric power generation using waste heat at intermediate temperature range (6500 to 8500 K). We will present our recent results on production of n- and p- type PbTe crystals and their thermoelectric characterization. Relative characteristics and performance of PbTe bulk single crystals and nano composites for thermoelectric power generation will be discussed.

  19. Review of electric discharge microplasmas generated in highly fluctuating fluids: Characteristics and application to nanomaterials synthesis

    SciTech Connect

    Stauss, Sven Terashima, Kazuo; Muneoka, Hitoshi; Urabe, Keiichiro

    2015-05-15

    Plasma-based fabrication of novel nanomaterials and nanostructures is indispensible for the development of next-generation electronic devices and for green energy applications. In particular, controlling the interactions between plasmas and materials interfaces, and the plasma fluctuations, is crucial for further development of plasma-based processes and bottom-up growth of nanomaterials. Electric discharge microplasmas generated in supercritical fluids represent a special class of high-pressure plasmas, where fluctuations on the molecular scale influence the discharge properties and the possible bottom-up growth of nanomaterials. This review discusses an anomaly observed for direct current microplasmas generated near the critical point, a local decrease in the breakdown voltage. This anomalous behavior is suggested to be caused by the concomitant decrease of the ionization potential due to the formation of clusters near the critical point, and the formation of extended electron mean free paths caused by the high-density fluctuation near the critical point. It is also shown that in the case of dielectric barrier microdischarges generated close to the critical point, the high-density fluctuation of the supercritical fluid persists. The final part of the review discusses the application of discharges generated in supercritical fluids to synthesis of nanomaterials, in particular, molecular diamond—so-called diamondoids—by microplasmas generated inside conventional batch-type and continuous flow microreactors.

  20. Definitional Noise in Estimates of Water Use for Electrical Generation (Invited)

    NASA Astrophysics Data System (ADS)

    Diehl, T. H.

    2013-12-01

    A key challenge in water-resources planning and policy is determining how much water is withdrawn and consumed to meet various needs. In the case of electrical power generation, quantifying water use is beset by differences and confusion in defining the basic terms relating water used in generating electricity to its hydrologic context, leading to wide disagreement on the amounts of withdrawal and consumption. Water withdrawals by plants with artificial cooling ponds, water consumption by plants with once-through cooling systems, and water diversion and consumption associated with hydroelectric power generation provide three examples of this 'definitional noise'. Plants that use cooling ponds withdraw water from other water bodies to make up for water lost from the pond, primarily as evaporation. Some of these plants report as withdrawal all flow from the pond to the condenser; others report only the much smaller flows needed to make up for water lost from the pond. Inconsistent assignment of plants to these two categories produces differences of several billion gallons per day in withdrawal estimates. Estimates of water consumption at plants with once-through cooling systems directly connected to natural surface water bodies vary substantially depending on whether 'consumption' is defined as being restricted to water loss within the plant or includes forced evaporation outside the plant caused by heat from the warmed cooling water returned to the source water body. Blurring of this distinction has produced wildly divergent consumption estimates. Differences in defining the processes that constitute water use for electrical generation produce dramatic differences in estimated water use. Historically, hydroelectric plants have been defined as having no water withdrawals or consumption. However, if flow through hydroelectric turbines were treated as withdrawal it would dwarf all other types of withdrawal, and if evaporation from reservoirs used for hydroelectric

  1. Generation of Runaway Electrons Induced by Cosmic-Ray Muons in Thunderstorm Electric Fields

    NASA Astrophysics Data System (ADS)

    Torii, T.; Nishijima, T.; Sugita, T.; Kawasaki, Z.

    2004-05-01

    Gamma ray dose-rate increases associated with winter thunderstorm activities have been observed in the coastal areas facing the Sea of Japan [1]. In order to investigate the generation of energetic photons which originate in thunderstorm electric fields, we have calculated the behavior of secondary cosmic ray electrons and photons in electric fields with Monte Carlo method. In the calculation, the electron and photon fluxes have increased greatly in the region where the field strength exceeds about 280 P(z) kV/m-atm, and these energy spectra show a large increase in the energy region up to several MeV [2]. In addition to the analysis of the electromagnetic component of cosmic rays, we have carried out the Monte Carlo transport calculations of the cosmic-ray muons and associated particles (e.g. knock-on electrons and bremsstrahlung photons) in thunderstorm electric fields, using GEANT4 code [3]. Muons form a large part of the secondary cosmic-rays and directly reach the regions of strong electric fields owing to their high penetrability in the atmosphere. Therefore, they can serve as the source of a considerable amount of runaway electrons, through their ionization process with air molecules, and their decay into energetic electrons. The electron and photon fluxes show notable increases in the strong electric field, while the muon flux does not fluctuate significantly. These results indicate that the production of energetic electrons by cosmic ray muons plays an important role in the enhancement of electron and photon fluxes in thunderstorm electric fields. Finally, we discuss a feasibility of muon-triggered lightning deduced from the muon transport calculation inside thunderstorm electric fields. From the calculation results, we estimate that the irradiation of muon beams rapidly increases energy deposition in the region of strong electric fields, and produce numerous electron - ion pairs. These productions may induce the lightning discharge by the runaway

  2. A space-based combined thermophotovoltaic electric generator and gas laser solar energy conversion system

    NASA Technical Reports Server (NTRS)

    Yesil, Oktay

    1989-01-01

    This paper describes a spaceborne energy conversion system consisting of a thermophotovoltaic electric generator and a gas laser. As a power source for the converson, the system utilizes an intermediate blackbody cavity heated to a temperature of 2000-2400 K by concentrated solar radiation. A double-layer solar cell of GaAs and Si forms a cylindrical surface concentric to this blackbody cavity, receiving the blackbody radiation and converting it into electricity with cell conversion efficiency of 50 percent or more. If the blackbody cavity encloses a laser medium, the blackbody radiation can also be used to simultaneously pump a lasing gas. The feasibility of blackbody optical pumping at 4.3 microns in a CO2-He gas mixture was experimentally demonstrated.

  3. Proposed guidelines for reporting performance of a solar dish/Stirling electric generation system

    SciTech Connect

    Stine, W.B.; Powell, M.A.

    1992-12-31

    Experimental performance data from dish/Stirling system testing can be analyzed to generate a system performance model. An approach to developing an experimentally based performance model of a dish/Stirling system is given. Two methods for analyzing the experimental data are described. To provide information that will permit comparison of dish/Stirling systems, it is necessary to define many of the details involved in calculating system performance data such as the net system output and system solar-to-electric efficiency. This paper describes a set of guidelines for these calculations, based on past experience, especially with the Vanguard dish/Stirling system. Also presented are a set of rating conditions at which a maximum value for system efficiency can be calculated. Comparison between systems of their rated peak solar-to-electric efficiency is made possible when these rating conditions are in common use by manufacturers and testing agencies.

  4. Enhanced labeling of microalgae cellular lipids by application of an electric field generated by alternating current.

    PubMed

    Su, Li-Chien; Hsu, Yi-Hsiang; Wang, Hsiang-Yu

    2012-05-01

    An alternating current was used to generate an electric field to enhance the fluorescent labeling of microalgae cellular lipids with Nile red and LipidTOX. The decay of the fluorescence intensity of Chlorella vulgaris cells in 0 V/cm was more than 50% after 10 min, and the intensity variation was as high as 7% in 20s. At 2000 V/cm, the decay rate decreased to 1.22% per minute and the intensity fluctuation was less than 1% for LipidTOX-labeled cells. For Spirulina sp. cells at 0 V/cm, the fluorescence intensity increased by 10% after 10 min, whereas at 2000 V/cm, labeling was more rapid and fluorescence intensity doubled. These results show that applying an electric field can improve the quality of fluorescence detection by alleviating decay and fluctuation or by enhancing signal intensity.

  5. Ocean thermal gradient as a generator of electricity. OTEC power plant

    NASA Astrophysics Data System (ADS)

    Enrique, Luna-Gomez Victor; Angel, Alatorre-Mendieta Miguel

    2016-04-01

    The OTEC (Ocean Thermal Energy Conversion) is a power plant that uses the thermal gradient of the sea water between the surface and a depth of about 700 meters. It works by supplying the heat to a steam machine, for evaporation, with sea water from the surface and cold, to condense the steam, with deep sea water. The energy generated by the power plant OTEC can be transferred to the electric power grid, another use is to desalinate seawater. During the twentieth century in some countries experimental power plants to produce electricity or obtaining drinking water they were installed. On the Mexico's coast itself this thermal gradient, as it is located in tropical seas it occurs, so it has possibilities of installing OTEC power plant type. In this paper one type OTEC power plant operation is represented in most of its components.

  6. High-order harmonic generation in the presence of a static electric field

    SciTech Connect

    Odzak, S.; Milosevic, D.B.

    2005-09-15

    We consider high-order harmonic generation by a linearly polarized laser field and a parallel static electric field. We first develop a modified saddle-point method which enables a quantitative analysis of the harmonic spectra even in the presence of Coulomb singularities. We introduce a classification of the saddle-point solutions and show that, in the presence of a static electric field which breaks the inversion symmetry, an additional classification number has to be introduced and that the usual saddle-point approximation and the uniform approximation in the case of the coalescing saddle points have to be modified. The theory developed offers a simple and accurate explanation of the static-field-induced multiplateau structure of the harmonic spectra. The longer quantum orbits are responsible for a long extension of the harmonic plateau, while the larger initial electron velocities are the reason of lower harmonic emission rates.

  7. Hantavirus infections among overnight visitors to Yosemite National Park, California, USA, 2012.

    PubMed

    Núñez, Jonathan J; Fritz, Curtis L; Knust, Barbara; Buttke, Danielle; Enge, Barryett; Novak, Mark G; Kramer, Vicki; Osadebe, Lynda; Messenger, Sharon; Albariño, César G; Ströher, Ute; Niemela, Michael; Amman, Brian R; Wong, David; Manning, Craig R; Nichol, Stuart T; Rollin, Pierre E; Xia, Dongxiang; Watt, James P; Vugia, Duc J

    2014-03-01

    In summer 2012, an outbreak of hantavirus infections occurred among overnight visitors to Yosemite National Park in California, USA. An investigation encompassing clinical, epidemiologic, laboratory, and environmental factors identified 10 cases among residents of 3 states. Eight case-patients experienced hantavirus pulmonary syndrome, of whom 5 required intensive care with ventilatory support and 3 died. Staying overnight in a signature tent cabin (9 case-patients) was significantly associated with becoming infected with hantavirus (p<0.001). Rodent nests and tunnels were observed in the foam insulation of the cabin walls. Rodent trapping in the implicated area resulted in high trap success rate (51%), and antibodies reactive to Sin Nombre virus were detected in 10 (14%) of 73 captured deer mice. All signature tent cabins were closed and subsequently dismantled. Continuous public awareness and rodent control and exclusion are key measures in minimizing the risk for hantavirus infection in areas inhabited by deer mice. PMID:24565589

  8. Catabolic and regulatory systems in Shewanella oneidensis MR-1 involved in electricity generation in microbial fuel cells

    PubMed Central

    Kouzuma, Atsushi; Kasai, Takuya; Hirose, Atsumi; Watanabe, Kazuya

    2015-01-01

    Shewanella oneidensis MR-1 is a facultative anaerobe that respires using a variety of inorganic and organic compounds. MR-1 is also capable of utilizing extracellular solid materials, including anodes in microbial fuel cells (MFCs), as electron acceptors, thereby enabling electricity generation. As MFCs have the potential to generate electricity from biomass waste and wastewater, MR-1 has been extensively studied to identify the molecular systems that are involved in electricity generation in MFCs. These studies have demonstrated the importance of extracellular electron-transfer (EET) pathways that electrically connect the quinone pool in the cytoplasmic membrane to extracellular electron acceptors. Electricity generation is also dependent on intracellular catabolic pathways that oxidize electron donors, such as lactate, and regulatory systems that control the expression of genes encoding the components of catabolic and electron-transfer pathways. In addition, recent findings suggest that cell-surface polymers, e.g., exopolysaccharides, and secreted chemicals, which function as electron shuttles, are also involved in electricity generation. Despite these advances in our knowledge on the EET processes in MR-1, further efforts are necessary to fully understand the underlying intra- and extracellular molecular systems for electricity generation in MFCs. We suggest that investigating how MR-1 coordinates these systems to efficiently transfer electrons to electrodes and conserve electrochemical energy for cell proliferation is important for establishing the biological basis for MFCs. PMID:26136738

  9. Effects of static electric fields on growth and development of wheat aphid Sitobion aveanae (Hemiptera: Aphididae) through multiple generations.

    PubMed

    He, Juan; Cao, Zhu; Yang, Jie; Zhao, Hui-Yan; Pan, Wei-Dong

    2016-01-01

    Insects show a variety of responses to electric fields and most of them are associated with immediate effects. To investigate the long-term effects of static electric field on the wheat aphid Sitbion avenae, the insert was exposed to 4 min of a static electric field at intensities of 0, 2, 4, or 6 kV/cm. Development effects over 30 consecutive generations of the insect were studied. The results showed that the electric field could exert adverse effects on the developmental duration and total longevity of S. avenae nymphs regardless of exposure intensities or generations. The effects appeared to be more intense and fluctuated at higher electric field intensities and more insect generations. The most favorable exposure for development was 6 kV/cm for 4 min while the most detrimental electric fields were 2 kV/cm for 4 min and 4 kV/cm for 4 min. Among the treatments, the first instar duration was significantly prolonged while the adult longevities were significantly shortened in the sixth generation. The intrinsic rate of increase and net reproductive rate in the sixth generation were also the lowest among the 30 consecutive generations studied. Based on the results, the adverse effects of electric fields on insects may be used in the bio-control of pest insects in terms of pest management.

  10. Study of the shock waves characteristics generated by underwater electrical wire explosion

    NASA Astrophysics Data System (ADS)

    Li, Xingwen; Chao, Youchuang; Wu, Jian; Han, Ruoyu; Zhou, Haibin; Qiu, Aici

    2015-07-01

    A model is proposed to simulate the generation and propagation of the shock wave (SW) produced by underwater electrical wire explosion in microsecond timescale, with the assumption that the exploding wire instantly turns into uniform discharge plasma channel (DPC) after the onset of explosion. To describe the interaction between the DPC and the surrounding water medium, the initial temperature of DPC is obtained by fitting calculated pressures with experimental data, and the injected energy of DPC is provided by the measured discharge current after wire explosion. To attenuate the high frequency oscillations generated by the discretization, the method with the double artificial viscosity parameters is proposed to calculate the SW propagation characteristics, and the input parameter is the above-calculated DPC boundary trajectory. Based on the proposed model, the DPC and SW properties of an underwater copper wire explosion are analyzed. The results show that the estimated initial temperature of DPC is about 15 000 K, the attenuation of peak pressure can be characterized by a law of the radial propagation distance r to the power of -0.74, and the efficiency transferred from stored electrical energy to the exploding wire and the generated water flow are ˜71.5% and ˜10%, respectively.

  11. Electricity and H2 generation from hemicellulose by sequential fermentation and microbial fuel/electrolysis cell

    NASA Astrophysics Data System (ADS)

    Yan, Di; Yang, Xuewei; Yuan, Wenqiao

    2015-09-01

    Electricity and hydrogen generation by bacteria Geobacter sulfurreducens in a dual-chamber microbial fuel/electrolysis cell following the fermentation of hemicellulose by bacteria Moorella thermoacetica was investigated. Experimental results showed that 10 g l-1 xylose under 60 °C was appropriate for the fermentation of xylose by M. thermoacetica, yielding 0.87 g-acetic acid per gram of xylose consumed. Corncob hydrolysate could also be fermented to produce acetic acid, but with lower yield (0.74 g-acid per g-xylose). The broths of xylose and corncob hydrolysate fermented by M. thermoacetica containing acetic acid were fed to G. sulfurreducens in a dual-chamber microbial fuel/electrolysis cell for electricity and hydrogen generation. The highest open-circuit cell voltages generated were 802 and 745 mV, and hydrogen yields were 41.7 and 23.3 mmol per mol-acetate, in xylose and corncob hydrolysate fermentation broth media, respectively. The internal resistance of the microbial fuel/electrolysis cell fed with corncob hydrolysate fermentation broth (3472 Ω) was much higher than that with xylose fermentation broth (1993 Ω) or sodium acetate medium (467 Ω), which was believed to be the main cause of the variation in hydrogen yield of the three feeding media.

  12. On the generation of nonlinear travelling waves in confined geometries using electric fields

    PubMed Central

    Cimpeanu, R; Papageorgiou, D. T

    2014-01-01

    We investigate electrostatically induced interfacial instabilities and subsequent generation of nonlinear coherent structures in immiscible, viscous, dielectric multi-layer stratified flows confined in small-scale channels. Vertical electric fields are imposed across the channel to produce interfacial instabilities that would normally be absent in such flows. In situations when the imposed vertical fields are constant, interfacial instabilities emerge due to the presence of electrostatic forces, and we follow the nonlinear dynamics via direct numerical simulations. We also propose and illustrate a novel pumping mechanism in microfluidic devices that does not use moving parts. This is achieved by first inducing interfacial instabilities using constant background electric fields to obtain fully nonlinear deformations. The second step involves the manipulation of the imposed voltage on the lower electrode (channel wall) to produce a spatio-temporally varying voltage there, in the form of a travelling wave with pre-determined properties. Such travelling wave dielectrophoresis methods are shown to generate intricate fluid–surface–structure interactions that can be of practical value since they produce net mass flux along the channel and thus are candidates for microfluidic pumps without moving parts. We show via extensive direct numerical simulations that this pumping phenomenon is a result of an externally induced nonlinear travelling wave that forms at the fluid–fluid interface and study the characteristics of the generated velocity field inside the channel. PMID:24936019

  13. On the generation of nonlinear travelling waves in confined geometries using electric fields.

    PubMed

    Cimpeanu, R; Papageorgiou, D T

    2014-07-28

    We investigate electrostatically induced interfacial instabilities and subsequent generation of nonlinear coherent structures in immiscible, viscous, dielectric multi-layer stratified flows confined in small-scale channels. Vertical electric fields are imposed across the channel to produce interfacial instabilities that would normally be absent in such flows. In situations when the imposed vertical fields are constant, interfacial instabilities emerge due to the presence of electrostatic forces, and we follow the nonlinear dynamics via direct numerical simulations. We also propose and illustrate a novel pumping mechanism in microfluidic devices that does not use moving parts. This is achieved by first inducing interfacial instabilities using constant background electric fields to obtain fully nonlinear deformations. The second step involves the manipulation of the imposed voltage on the lower electrode (channel wall) to produce a spatio-temporally varying voltage there, in the form of a travelling wave with pre-determined properties. Such travelling wave dielectrophoresis methods are shown to generate intricate fluid-surface-structure interactions that can be of practical value since they produce net mass flux along the channel and thus are candidates for microfluidic pumps without moving parts. We show via extensive direct numerical simulations that this pumping phenomenon is a result of an externally induced nonlinear travelling wave that forms at the fluid-fluid interface and study the characteristics of the generated velocity field inside the channel. PMID:24936019

  14. Life cycle water use for electricity generation: a review and harmonization of literature estimates

    NASA Astrophysics Data System (ADS)

    Meldrum, J.; Nettles-Anderson, S.; Heath, G.; Macknick, J.

    2013-03-01

    This article provides consolidated estimates of water withdrawal and water consumption for the full life cycle of selected electricity generating technologies, which includes component manufacturing, fuel acquisition, processing, and transport, and power plant operation and decommissioning. Estimates were gathered through a broad search of publicly available sources, screened for quality and relevance, and harmonized for methodological differences. Published estimates vary substantially, due in part to differences in production pathways, in defined boundaries, and in performance parameters. Despite limitations to available data, we find that: water used for cooling of thermoelectric power plants dominates the life cycle water use in most cases; the coal, natural gas, and nuclear fuel cycles require substantial water per megawatt-hour in most cases; and, a substantial proportion of life cycle water use per megawatt-hour is required for the manufacturing and construction of concentrating solar, geothermal, photovoltaic, and wind power facilities. On the basis of the best available evidence for the evaluated technologies, total life cycle water use appears lowest for electricity generated by photovoltaics and wind, and highest for thermoelectric generation technologies. This report provides the foundation for conducting water use impact assessments of the power sector while also identifying gaps in data that could guide future research.

  15. Sustainable electricity generation by solar pv/diesel hybrid system without storage for off grids areas

    NASA Astrophysics Data System (ADS)

    Azoumah, Y.; Yamegueu, D.; Py, X.

    2012-02-01

    Access to energy is known as a key issue for poverty reduction. The electrification rate of sub Saharan countries is one of the lowest among the developing countries. However this part of the world has natural energy resources that could help raising its access to energy, then its economic development. An original "flexy energy" concept of hybrid solar pv/diesel/biofuel power plant, without battery storage, is developed in order to not only make access to energy possible for rural and peri-urban populations in Africa (by reducing the electricity generation cost) but also to make the electricity production sustainable in these areas. Some experimental results conducted on this concept prototype show that the sizing of a pv/diesel hybrid system by taking into account the solar radiation and the load/demand profile of a typical area may lead the diesel generator to operate near its optimal point (70-90 % of its nominal power). Results also show that for a reliability of a PV/diesel hybrid system, the rated power of the diesel generator should be equal to the peak load. By the way, it has been verified through this study that the functioning of a pv/Diesel hybrid system is efficient for higher load and higher solar radiation.

  16. Background-free electric field-induced second harmonic generation with interdigitated combs of electrodes.

    PubMed

    Jašinskas, Vidmantas; Gedvilas, Mindaugas; Račiukaitis, Gediminas; Gulbinas, Vidmantas

    2016-06-15

    The electric field-induced second harmonic (EFISH) generation is a powerful tool for the investigation of optical nonlinearities, material polarization, internal electric fields, and other properties of photonic materials and devices. A conventional generation of the second harmonics (SH) in materials with the disturbed centrosymmetry causes a field-independent background to EFISH and limits its applications. Here we suggest and analyze the application of the interdigitated combs of electrodes for EFISH generation in thin films. Interdigitated electrodes form an optical transmission amplitude diffraction grating. Phase matching of the EFISH radiation creates unusual diffraction fringes with the zero intensity along the zeroth order direction and with the diffraction angles different from diffraction angles of incident fundamental laser radiation and its second harmonics. It enables a simple geometrical separation of the EFISH signal from a conventional SH background, simplifies the sample preparation, and provides additional experimental possibilities. We demonstrate applicability of the suggested technique for characterization of submicrometer thickness organic films of transparent and resonantly interacting polymers and of their mixtures. PMID:27304282

  17. Recovery Act: Brea California Combined Cycle Electric Generating Plant Fueled by Waste Landfill Gas

    SciTech Connect

    Galowitz, Stephen

    2012-12-31

    The primary objective of the Project was to maximize the productive use of the substantial quantities of waste landfill gas generated and collected at the Olinda Landfill near Brea, California. An extensive analysis was conducted and it was determined that utilization of the waste gas for power generation in a combustion turbine combined cycle facility was the highest and best use. The resulting Project reflected a cost effective balance of the following specific sub-objectives: • Meeting the environmental and regulatory requirements, particularly the compliance obligations imposed on the landfill to collect, process and destroy landfill gas • Utilizing proven and reliable technology and equipment • Maximizing electrical efficiency • Maximizing electric generating capacity, consistent with the anticipated quantities of landfill gas generated and collected at the Olinda Landfill • Maximizing equipment uptime • Minimizing water consumption • Minimizing post-combustion emissions • The Project produced and will produce a myriad of beneficial impacts. o The Project created 360 FTE construction and manufacturing jobs and 15 FTE permanent jobs associated with the operation and maintenance of the plant and equipment. o By combining state-of-the-art gas clean up systems with post combustion emissions control systems, the Project established new national standards for best available control technology (BACT). o The Project will annually produce 280,320 MWh’s of clean energy o By destroying the methane in the landfill gas, the Project will generate CO2 equivalent reductions of 164,938 tons annually. The completed facility produces 27.4 MWnet and operates 24 hours a day, seven days a week.

  18. Effects on electrical distribution networks of dispersed power generation at high levels of connection penetration

    SciTech Connect

    Longrigg, P

    1983-07-01

    The advent and deployment of significant levels of photovoltaic and wind energy generation in the spatially dispersed mode (i.e., residential and intermediate load centers) may have deleterious effects upon existing protective relay equipment and its time-current coordination on radial distribution circuits to which power conditioning equipment may be connected for power sell-back purposes. The problems that may arise involve harmonic injection from power conditioning inverters that can affect protective relays and cause excessive voltage and current from induced series and parallel resonances on feeders and connected passive equipment. Voltage regulation, var requirements, and consumer metering can also be affected by this type of dispersed generation. The creation of islands of supply is also possible, particularly on rural supply systems. This paper deals mainly with the effects of harmonics and short-circuit currents from wind energy conversion systems (WECS) and photovoltaic (PV) systems upon the operating characteristics of distribution networks and relays and other protective equipment designed to ensure the safety and supply integrity of electrical utility networks. Traditionally, electrical supply networks have been designed for one-way power flow-from generation to load, with a balance maintained between the two by means of automatic generation and load-frequency controls. Dispersed generation, from renewables like WECS or PV or from nonrenewable resources, can change traditional power flow. These changes must be dealt with effectively if renewable energy resources are to be integrated into the utility distribution system. This paper gives insight into these problems and proposes some solutions.

  19. Overnight S100B in Parkinson's Disease: A glimpse into sleep-related neuroinflammation.

    PubMed

    Carvalho, D Z; Schönwald, S V; Schumacher-Schuh, A F; Braga, C W; Souza, D O; Oses, J P; Donis, K C; Rieder, C R

    2015-11-01

    Calcium-binding protein B (S100B), a primary product of astrocytes, is a proposed marker of Parkinson's Disease (PD) pathophysiology, diagnosis and progression. However, it has also been implicated in sleep disruption, which is very common in PD. To explore the relationship between S100B, disease severity, sleep symptoms and polysomnography (PSG) findings, overnight changes in serum S100B levels were investigated for the first time in PD. 17 fully treated, non-demented, moderately advanced PD patients underwent PSG and clinical assessment of sleep symptoms. Serum S100B samples were collected immediately before and after the PSG. Results are shown as median [interquartile range]. Night and morning S100B levels were similar, but uncorrelated (rs=-0.277, p=0.28). Morning S100B levels, as opposed to night levels, positively correlated with the Unified Parkinson's Disease rating scale (UPDRS) subsections I and II (rs=0.547, p=0.023; rs=0.542, p=0.025). Compared to those with overnight S100B reduction, patients with overnight S100B elevation had higher H&Y scores (2.5 [0.87] vs. 2 [0.25], p=0.035) and worse total Pittsburgh Sleep Quality Index (PSQI) and Parkinson's Disease Sleep Scores (10 [3.2] vs. 8 [4.5], p=0.037; 92.9 [39] vs. 131.4 [28], p=0.034). Correlation between morning S100B levels and total UPDRS score was strengthened after controlling for total PSQI score (rs=0.531, p=0.034; partial rs=0.699, p=0.004, respectively). Overnight S100B variation and morning S100B were associated with PD severity and perceived sleep disruption. S100B is proposed as a putative biomarker for sleep-related neuroinflammation in PD. Noradrenergic-astrocytic dysfunction is hypothesized as a possible mechanism underlying these findings. PMID:26453767

  20. Overnight heart rate variability in patients with obstructive sleep apnoea: a time and frequency domain study.

    PubMed

    Zhu, Kaixian; Chemla, Denis; Roisman, Gabriel; Mao, Wenyuan; Bazizi, Samir; Lefevre, Amaury; Escourrou, Pierre

    2012-11-01

    Heightened sympathetic activity plays a role in the cardiovascular sequelae of obstructive sleep apnoea (OSA). Cardiac autonomic function may be assessed non-invasively by studying heart rate variability (HRV). The aim of the present study was to compare overnight HRV between a control group and a group of subjects with severe OSA. The potential confounding effects of age, sex, baseline autonomic status and sleep stage distribution were taken into account. Our prospective Holter study compared overnight (0030-0530 hours) HRV in 23 controls (apnoea hypopnoea index (AHI) = 5 ± 3 /h) and 23 subjects with severe OSA (AHI = 65 ± 23 /h), matched for age and sex and with a similar percentage of rapid eye movement sleep. The mean normal-to-normal RR interval (NN) was shorter in the OSA compared with control group (903 vs 1039 ms, respectively), whereas the other time-domain indices of HRV, as well as the classic frequency-domain indices, were similar. Essentially similar results were obtained hourly and when only subjects with high mean values of the standard deviation of all NN (≥ 90 ms) were evaluated. In the 0.01-0.06 Hz range corresponding to the typical OSA pattern of bradycardia-tachycardia termed cyclic variation of heart rate (CVHR), higher power was documented hourly in OSA, with a significant correlation between overnight power and both AHI and mean oxyhaemoglobin saturation. The percentage of NN > x ms different from the previous one (pNNx family) had no diagnostic value. The results of the present study suggest that NN may be the best index to quantify the overnight sympathovagal balance in OSA and that a spectral band overlapping the apnoea-related pattern of CVHR slightly improved the characterization of the apnoea-related HRV patterns.

  1. Overnight S100B in Parkinson's Disease: A glimpse into sleep-related neuroinflammation.

    PubMed

    Carvalho, D Z; Schönwald, S V; Schumacher-Schuh, A F; Braga, C W; Souza, D O; Oses, J P; Donis, K C; Rieder, C R

    2015-11-01

    Calcium-binding protein B (S100B), a primary product of astrocytes, is a proposed marker of Parkinson's Disease (PD) pathophysiology, diagnosis and progression. However, it has also been implicated in sleep disruption, which is very common in PD. To explore the relationship between S100B, disease severity, sleep symptoms and polysomnography (PSG) findings, overnight changes in serum S100B levels were investigated for the first time in PD. 17 fully treated, non-demented, moderately advanced PD patients underwent PSG and clinical assessment of sleep symptoms. Serum S100B samples were collected immediately before and after the PSG. Results are shown as median [interquartile range]. Night and morning S100B levels were similar, but uncorrelated (rs=-0.277, p=0.28). Morning S100B levels, as opposed to night levels, positively correlated with the Unified Parkinson's Disease rating scale (UPDRS) subsections I and II (rs=0.547, p=0.023; rs=0.542, p=0.025). Compared to those with overnight S100B reduction, patients with overnight S100B elevation had higher H&Y scores (2.5 [0.87] vs. 2 [0.25], p=0.035) and worse total Pittsburgh Sleep Quality Index (PSQI) and Parkinson's Disease Sleep Scores (10 [3.2] vs. 8 [4.5], p=0.037; 92.9 [39] vs. 131.4 [28], p=0.034). Correlation between morning S100B levels and total UPDRS score was strengthened after controlling for total PSQI score (rs=0.531, p=0.034; partial rs=0.699, p=0.004, respectively). Overnight S100B variation and morning S100B were associated with PD severity and perceived sleep disruption. S100B is proposed as a putative biomarker for sleep-related neuroinflammation in PD. Noradrenergic-astrocytic dysfunction is hypothesized as a possible mechanism underlying these findings.

  2. Overnight consolidation promotes generalization across talkers in the identification of nonnative speech sounds.

    PubMed

    Earle, F Sayako; Myers, Emily B

    2015-01-01

    This investigation explored the generalization of phonetic learning across talkers following training on a nonnative (Hindi dental and retroflex) contrast. Participants were trained in two groups, either in the morning or in the evening. Discrimination and identification performance was assessed in the trained talker and an untrained talker three times over 24 h following training. Results suggest that overnight consolidation promotes generalization across talkers in identification, but not necessarily discrimination, of nonnative speech sounds. PMID:25618106

  3. A study of electrochemistry for Pathor Kuchi Leaf (PKL) electricity generation system

    NASA Astrophysics Data System (ADS)

    Khan, Md. Kamrul Alam; Alam, Md. Shamsul; Sultana, Jesmin; Mamun, M. A.

    2015-05-01

    Electrodes are put into the Bryophyllum Pinnatum Leaf (BPL) or Pathor Kuchi Leaf (PKL) sap and they produce substantially sufficient amount of electricity to power energy consumed electronics and electrical appliances. The role of CuSO4.5H2O solution has been studied. The electrical and chemical properties, a very important factor for PKL electricity generation device have been studied in this research work. The electrical properties are: internal resistance, voltage regulation, energy efficiency, pulse performance, self discharge characteristics, discharge characteristics with load, capacity of the PKL cell, temperature characteristics and life cycle of the PKL cell. The chemical properties are: The [Zn2+], [Cu2+] and quotient constant. The optimum level of the CuSO4.5H2O solution has been studied. The adherent/adherence effect of the electrodes for use in CuSO4.5H2O solution have been studied. The performance of the production of the two bi-products (fertilizer and hydrogen gas production) has been studied. Variation of concentration of Zn2+ and Cu2+ with the variation of percentage of the secondary salt (CuSO4. 5H2O), percentage of the water and the percentage of PKL sap have been studied. The change of PKL power efficiency with time has also been studied. Most of the results have been tabulated and graphically discussed. This study on showed that, internal resistance is nearly 0.60 ohm, voltage regulation is close to 9%, pulse performance is so good and energy efficiency is about 65%. Internal resistance is very much higher than the acceptable range.

  4. 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.

  5. Essays on applied auction problems in electric generation and in neighboring jurisdictions

    SciTech Connect

    Eastman-Perl, K.A.

    1993-01-01

    This work consists of three essays. The first essay, [open quotes]Contract Selection and Performance in Competitive Bidding for Electric Generation,[close quotes], studies the new practice of competitive bidding among third parties to supply utilities with electric generating capacity. The other two essays, entitled [open quotes]First Price Auctions in Neighboring Jurisdictions,[close quotes] and [open quotes]Second Price Auctions in Neighboring Jurisdictions,[close quotes] study the general problem of auctions when there are several auctioneers that can observe each other and can use information from these observations strategically. The first essay notes that competitive bidding programs for electric generation are really auctions of long-term contracts between utility and third parties. Bids and contracts from Maine were studied. Since Maine has a wealth of alternative fuels, such as wood and hydroelectric, the applicability of this study is limited to states with significant alternative fuel resources. The second and third essays consider auctions in neighboring jurisdictions. One concerns first-price auctions (low bid, wins, and is paid its bid), and the other concerns second-price auctions (low bid wins, and is paid the second lowest bid). One town initially holds an auction, the results of which are public information. Another town can use this public information to negotiate with the winner of the initial auction. Firms always bid higher in an initial first-price auction than they would if a neighboring town were not present. In equilibrium, firms are no worse off than they would be if both towns acted independently, and the negotiating town benefits at the expense of the town initially auctioning. In second-price auctions, the incentive compatibility property is preserved if relatively lower cost firms bid in the initial auction. The town initially conducting the auction is unaffected, and the negotiating town benefits at the firm's expense.

  6. Enzymatic hydrolysis of cellulose coupled with electricity generation in a microbial fuel cell.

    PubMed

    Rezaei, Farzaneh; Richard, Tom L; Logan, Bruce E

    2008-12-15

    Electricity can be directly generated by bacteria in microbial fuel cells (MFCs) from a variety of biodegradable substrates, including cellulose. Particulate materials have not been extensively examined for power generation in MFCs, but in general power densities are lower than those produced with soluble substrates under similar conditions likely as a result of slow hydrolysis rates of the particles. Cellulases are used to achieve rapid conversion of cellulose to sugar for ethanol production, but these enzymes have not been previously tested for their effectiveness in MFCs. It was not known if cellulases would remain active in an MFC in the presence of exoelectrogenic bacteria or if enzymes might hinder power production by adversely affecting the bacteria. Electricity generation from cellulose was therefore examined in two-chamber MFCs in the presence and absence of cellulases. The maximum power density with enzymes and cellulose was 100 +/- 7 mW/m(2) (0.6 +/- 0.04 W/m(3)), compared to only 12 +/- 0.6 mW/m(2) (0.06 +/- 0.003 W/m(3)) in the absence of the enzymes. This power density was comparable to that achieved in the same system using glucose (102 +/- 7 mW/m(2), 0.56 +/- 0.038 W/m(3)) suggesting that the enzyme successfully hydrolyzed cellulose and did not otherwise inhibit electricity production by the bacteria. The addition of the enzyme doubled the Coulombic efficiency (CE) to CE = 51% and increased COD removal to 73%, likely as a result of rapid hydrolysis of cellulose in the reactor and biodegradation of the enzyme. These results demonstrate that cellulases do not adversely affect exoelectrogenic bacteria that produce power in an MFC, and that the use of these enzymes can increase power densities and reactor performance.

  7. Behavioral changes in female Asian elephants when given access to an outdoor yard overnight.

    PubMed

    Powell, David M; Vitale, Cathy

    2016-07-01

    A study was conducted at the Bronx Zoo to determine whether providing elephants with access to an outdoor corral at night had any significant effects on behavior, use of space, and use of a sand corral. Activity budgets for three female Asian elephants were compared when the subjects were housed indoors overnight and when they were given access to an outdoor yard overnight. Observations were recorded via infrared video cameras between the hours of 1900 and 0700 during the months of July-September. Two of the three elephants showed a significant preference for spending time outdoors, whereas, the third elephant spent most of her time indoors. Standing and play behavior increased when the elephants had outdoor access while lying down and feeding behavior decreased. Swaying behavior decreased significantly when the elephants had access to the outdoor yard. The elephants made very little use of a sand-floor stall regardless of whether or not they had access to outdoors. The results of this study, suggest that having access to alternate areas overnight can promote well-being by reducing repetitive behavior and allowing animals to express their preferences for different locations. The relative importance of choice alone vs. the behavioral opportunities provided by choice options for zoo animals is discussed. Zoo Biol. 35:298-303, 2016. © 2016 Wiley Periodicals, Inc.

  8. Clean Energy Technologies: A Preliminary Inventory of the Potential for Electricity Generation

    SciTech Connect

    Bailey, Owen; Worrell, Ernst

    2005-08-03

    The nation's power system is facing a diverse and broad set of challenges. These range from restructuring and increased competitiveness in power production to the need for additional production and distribution capacity to meet demand growth, and demands for increased quality and reliability of power and power supply. In addition, there are growing concerns about emissions from fossil fuel powered generation units and generators are seeking methods to reduce the CO{sub 2} emission intensity of power generation. Although these challenges may create uncertainty within the financial and electricity supply markets, they also offer the potential to explore new opportunities to support the accelerated deployment of cleaner and cost-effective technologies to meet such challenges. The federal government and various state governments, for example, support the development of a sustainable electricity infrastructure. As part of this policy, there are a variety of programs to support the development of ''cleaner'' technologies such as combined heat and power (CHP, or cogeneration) and renewable energy technologies. Energy from renewable energy sources, such as solar, wind, hydro, and biomass, are considered carbon-neutral energy technologies. The production of renewable energy creates no incremental increase in fossil fuel consumption and CO{sub 2} emissions. Electricity and thermal energy production from all renewable resources, except biomass, produces no incremental increase in air pollutants such as nitrogen oxides, sulfur oxides, particulate matter, and carbon monoxide. There are many more opportunities for the development of cleaner electricity and thermal energy technologies called ''recycled'' energy. A process using fossil fuels to produce an energy service may have residual energy waste streams that may be recycled into useful energy services. Recycled energy methods would capture energy from sources that would otherwise be unused and convert it to electricity or

  9. Short run effects of a price on carbon dioxide emissions from U.S. electric generators.

    PubMed

    Newcomer, Adam; Blumsack, Seth A; Apt, Jay; Lave, Lester B; Morgan, M Granger

    2008-05-01

    The price of delivered electricity will rise if generators have to pay for carbon dioxide emissions through an implicit or explicit mechanism. There are two main effects that a substantial price on CO2 emissions would have in the short run (before the generation fleet changes significantly). First, consumers would react to increased price by buying less, described by their price elasticity of demand. Second, a price on CO2 emissions would change the order in which existing generators are economically dispatched, depending on their carbon dioxide emissions and marginal fuel prices. Both the price increase and dispatch changes depend on the mix of generation technologies and fuels in the region available for dispatch, although the consumer response to higher prices is the dominant effect. We estimate that the instantaneous imposition of a price of $35 per metric ton on CO2 emissions would lead to a 10% reduction in CO2 emissions in PJM and MISO at a price elasticity of -0.1. Reductions in ERCOT would be about one-third as large. Thus, a price on CO2 emissions that has been shown in earlier workto stimulate investment in new generation technology also provides significant CO2 reductions before new technology is deployed at large scale.

  10. Short run effects of a price on carbon dioxide emissions from U.S. electric generators

    SciTech Connect

    Adam Newcomer; Seth A. Blumsack; Jay Apt; Lester B. Lave; M. Granger Morgan

    2008-05-01

    The price of delivered electricity will rise if generators have to pay for carbon dioxide emissions through an implicit or explicit mechanism. There are two main effects that a substantial price on CO{sub 2} emissions would have in the short run (before the generation fleet changes significantly). First, consumers would react to increased price by buying less, described by their price elasticity of demand. Second, a price on CO{sub 2} emissions would change the order in which existing generators are economically dispatched, depending on their carbon dioxide emissions and marginal fuel prices. Both the price increase and dispatch changes depend on the mix of generation technologies and fuels in the region available for dispatch, although the consumer response to higher prices is the dominant effect. We estimate that the instantaneous imposition of a price of $35 per metric ton on CO{sub 2} emissions would lead to a 10% reduction in CO{sub 2} emissions in PJM and MISO at a price elasticity of -0.1. Reductions in ERCOT would be about one-third as large. Thus, a price on CO{sub 2} emissions that has been shown in earlier work to stimulate investment in new generation technology also provides significant CO{sub 2} reductions before new technology is deployed at large scale. 39 refs., 4 figs., 2 tabs.

  11. State-level Greenhouse Gas Emission Factors for Electricity Generation, Updated

    EIA Publications

    2001-01-01

    To assist reporters in estimating emissions and emission reductions, The Energy Information Administration (EIA) has made available in the instructions to Forms EIA-1605 and EIA-1605EZ emission coefficients for most commonly used fossil fuels and electricity. These coefficients were based on 1992 emissions and generation data. In 1999, updated coefficients were prepared based on the most recent data (1998) then available; however, the updated coefficients were not included in the instructions for the 1999 data year. This year, they have been updated again, but based on three years worth of data (1997, 1998, and 1999) rather than a single year.

  12. Quasi-distributed fiber Bragg grating temperature sensors for stator bars monitoring of large electric generators

    NASA Astrophysics Data System (ADS)

    Dreyer, Uilian J.; da Silva, Erlon V.; Biffe Di Renzo, André; Martelli, Cicero; Cardozo da Silva, Jean Carlos

    2016-05-01

    This work presents the application of a sensor based on quasi-distributed Fiber Bragg Gratings to monitor stator bars temperature of large electric generators. The applied FBG packaging method follows industrial standard procedures, and resulted in a robust and reliable sensing method, facilitating the future installation in the power plant. Experimental results are acquired in laboratory using the expected range of temperature values in the real machine. The measurement errors in the recorded results are within the calculated uncertainties and the time constant is shorter than what is obtained with conventional RTD for the same application.

  13. Experimental Hydrogen Plant with Metal Hydrides to Store and Generate Electrical Power

    NASA Astrophysics Data System (ADS)

    Gonzatti, Frank; Nizolli, Vinícius; Ferrigolo, Fredi Zancan; Farret, Felix Alberto; de Mello, Marcos Augusto Silva

    2016-02-01

    Generation of electrical energy with renewable sources is interruptible due to the primary energy characteristics (sun, wind, hydro, etc.). In these cases, it is necessary to use energy storage so increasing penetrability of these sources connected to the distribution system. This paper discusses in details some equipment and accessories of an integrated power plant using fuel cell stack, electrolyzer and metal hydrides. During the plant operation were collected the power consumption data and established the efficiency of each plant component. These data demonstrated an overall efficiency of about 11% due to the low efficiencies of the commercial electrolyzers and power inverters used in the experiments.

  14. Natural turbulence electrical power generator. [using wave action or random motion

    NASA Technical Reports Server (NTRS)

    Grana, D. C.; Wilem, R. T. (Inventor)

    1980-01-01

    An energy conversion apparatus is disclosed in which a stator, fixed to a watertight housing, is coupled to a rotor by a helical spring which suspends the rotor from the housing. Natural turbulence of a fluid, such as water or air, causes acceleration of the housing, and hence, acceleration of the stator. Inertia of the rotor, coupled to the stator through the helical spring and the housing, causes relative motion, both longitudinal and rotational, between the stator and the rotor. The rotational motion between the rotor, and the stator is used to generate electrical current.

  15. Optimal stack gas cleaning technology to maximize coal utilization in electric power generation

    SciTech Connect

    Emish, G.J.; Schulte, W.; Ellison, W.

    1997-07-01

    Major trends and developments are affecting availability, cost and comparative advantages to be assessed in choice of alternative primary energy/fuel sources and stack gas cleaning processes. As a result, electric power development can be seen to be in a traditional period leading to broadened, principal use of plentiful, higher-sulfur, fossil fuels, e.g. bituminous coal, petroleum coke, Orimulsion, etc., accompanied by gas cleaning system design affording minimum total cost per ton of SO{sub 2} removal in conjunction with advantageous, increased volume of high-value sulfurous byproduct generation.

  16. Renewable generation technology choice and policies in a competitive electricity supply industry

    NASA Astrophysics Data System (ADS)

    Sarkar, Ashok

    Renewable energy generation technologies have lower externality costs but higher private costs than fossil fuel-based generation. As a result, the choice of renewables in the future generation mix could be affected by the industry's future market-oriented structure because market objectives based on private value judgments may conflict with social policy objectives toward better environmental quality. This research assesses how renewable energy generation choices would be affected in a restructured electricity generation market. A multi-period linear programming-based model (Resource Planning Model) is used to characterize today's electricity supply market in the United States. The model simulates long-range (2000-2020) generation capacity planning and operation decisions under alternative market paradigms. Price-sensitive demand is used to simulate customer preferences in the market. Dynamically changing costs for renewables and a two-step load duration curve are used. A Reference Case represents the benchmark for a socially-optimal diffusion of renewables and a basis for comparing outcomes under alternative market structures. It internalizes externality costs associated with emissions of sulfur dioxide (SOsb2), nitrous oxides (NOsbx), and carbon dioxide (COsb2). A Competitive Case represents a market with many generation suppliers and decision-making based on private costs. Finally, a Market Power Case models the extreme case of market power: monopoly. The results suggest that the share of renewables would decrease (and emissions would increase) considerably in both the Competitive and the Market Power Cases with respect to the Reference Case. The reduction is greater in the Market Power Case due to pricing decisions under existing supply capability. The research evaluates the following environmental policy options that could overcome market failures in achieving an appropriate level of renewable generation: COsb2 emissions tax, SOsb2 emissions cap, renewable

  17. High-Efficiency Solar Cells for Large-Scale Electricity Generation & Design Considerations for the Related Optics (Presentation)

    SciTech Connect

    Kurtz, S.; Olson, J.; Geisz, J.; Friedman, D.; McMahon, W.; Ptak, A.; Wanlass, M.k; Kibbler, A.; Kramer, C.; Ward, S.; Duda, A.; Young, M.; Carapella, J.

    2007-09-17

    The photovoltaic industry has been growing exponentially at an average rate of about 35%/year since 1979. Recently, multijunction concentrator cell efficiencies have surpassed 40%. Combined with concentrating optics, these can be used for electricity generation.

  18. Experimental observation of increased threshold electric field for runaway generation due to synchrotron radiation losses in the FTU tokamak

    SciTech Connect

    Martin-Solis, Jose Ramon; Sanchez, Raul; Esposito, Basilio

    2010-01-01

    The threshold electric field for runaway generation has been investigated during runaway suppression experiments by means of electron-cyclotron-resonance heating in the flattop phase of FTU discharges. Runaway suppression has been experimentally found to occur at electric fields substantially larger than those predicted by the relativistic collisional theory of runaway generation, E{sub R} = n{sub e}e{sup 3}ln{Lambda}/4{pi}{var_epsilon}{sub 0}{sup 2}m{sub e}c{sup 2}. These experimental results are consistent with an increase of the critical electric field due to the electron synchrotron radiation losses. No runaway electrons are found in FTU experiments below the radiation threshold. These results support evidence for a new threshold electric field for runaway generation that accounts for the effect of the synchrotron losses, and which should be considered when making predictions on runaway generation and mitigation in devices such as ITER.

  19. Exploring the Basic Principles of Electric Motors and Generators with a Low-Cost Sophomore-Level Experiment

    ERIC Educational Resources Information Center

    Schubert, T. F.; Jacobitz, F. G.; Kim, E. M.

    2009-01-01

    In order to meet changing curricular needs, an electric motor and generator laboratory experience was designed, implemented, and assessed. The experiment is unusual in its early placement in the curriculum and in that it focuses on modeling electric motors, predicting their performance, and measuring efficiency of energy conversion. While…

  20. Comparative health and safety assessment of the SPS and alternative electrical generation systems

    NASA Technical Reports Server (NTRS)

    Habegger, L. J.; Gasper, J. R.; Brown, C. D.

    1980-01-01

    A comparative analysis of health and safety risks is presented for the Satellite Power System and five alternative baseload electrical generation systems: a low-Btu coal gasification system with an open-cycle gas turbine combined with a steam topping cycle; a light water fission reactor system without fuel reprocessing; a liquid metal fast breeder fission reactor system; a central station terrestrial photovoltaic system; and a first generation fusion system with magnetic confinement. For comparison, risk from a decentralized roof-top photovoltaic system with battery storage is also evaluated. Quantified estimates of public and occupational risks within ranges of uncertainty were developed for each phase of the energy system. The potential significance of related major health and safety issues that remain unquantitied are also discussed.