DEFF Research Database (Denmark)

Udgivelsesdato: JUL

Energy Technology Data Exchange (ETDEWEB)

This 2001 status on the use of renewable energies in France makes a synthesis of the electric and heat productions of renewable origin. It lists the primary or secondary productions of renewable energies, and details the uses corresponding to each renewable energy production source and their respective satisfaction of consumer's needs (residential, industry and agriculture sectors). A detail statistical status for 1999, 2000 and 2001 is presented in tables. (J.S.)

DEFF Research Database (Denmark)

Denmark has been one of the first countries in the world to commit itself to a sustainable energy development. This has been substantiated by two official action plans from 1990 and 1996 with emphasis on energy efficiency and supply systems based on renewable energy. In year 2005, renewable energy sources are planned to cover 12-14% and in year 2030 about 35% of total Danish energy demand. This paper reviews the experiences with implementation of renewable energy in Denmark with a focus on wind power and biomass.

Energy Technology Data Exchange (ETDEWEB)

This poster, submitted for the CU Energy Initiative/NREL Symposium on October 3, discusses the impacts of renewable fuel and electricity standards on state economies.

Energy Technology Data Exchange (ETDEWEB)

No abstract prepared.

Energy Technology Data Exchange (ETDEWEB)

Clear effects of the Act on Power Generation from Renewable Energy Sources (EEWaermeG) on the market cannot be recognized both for the depth geothermal energy and ground source geothermal energy. Due to the concrete design of the law a position that is inferior to others is attained in relation to some other renewable energy sources.

Energy Technology Data Exchange (ETDEWEB)

The aim of this report is to show how Energetic Planning and Territorial Policy should be working together for a better integration of Renewable Energies into Region. This Integration should to contemplate social, economic and environmental aspects of the territory. The report has been classified into 7 items: planning, energetic scenarios, technology transfer for Renewable Energies dissemination, barriers for this dissemination, environmental aspects, European Union Policy and Decision Support Systems (and specially GIS). (Author) 54 refs.

Energy Technology Data Exchange (ETDEWEB)

Assessing the potential environmental and human effects of deploying renewable energy on private and public lands, along our coasts, on the Outer Continental Shelf (OCS), and in the Great Lakes requires a new way of evaluating potential environmental and human impacts. The author argues that deployment of renewables requires a framework risk paradigm that underpins effective future siting decisions and public policies.

Energy Technology Data Exchange (ETDEWEB)

This document is an executive summary of the colloquium organized by the French syndicate of renewable energies (SER) which took place at the Maison de l'UNESCO in Paris during the national debate on energies organized by the French government in spring 2003. The colloquium was organized around 6 round tables dealing with: the world perspectives and the environmental context of the contribution of renewable energies to the sustainable development (respect of Kyoto protocol commitments, contribution to the security of energy supplies, lack of large scale program of development of decentralized power generation in developing countries, lack of market tools linked with CO{sub 2} emissions, improvement of competitiveness); development of renewable energies in Europe (promotion and sustain in all European countries, ...

Energy Technology Data Exchange (ETDEWEB)

Using the past diffusion trends of four renewable energy technologies for irrigation water pumping in India (SPV pumps, windmill pumps and biogas/producer gas driven dual fuel engine pumps), results of an attempt to project their future dissemination levels, have been presented in this study. The likely contribution of the renewable energy options considered in the study to the projected energy demand for irrigation water pumping in India has been estimated. Estimates of the associated investment requirements taking into account the learning effect have also been presented. (author)

Energy Technology Data Exchange (ETDEWEB)

This work, carried out by the parliamentary office for the evaluation of scientific and technological choices on request of the French National Assembly and Senate, takes stock of the present day situation and technical perspectives of development of renewable energy sources and of research needs of the French industry in this domain: 1 - renewable energies: key-technologies for the energy supply of developing countries and for a rational consumption in transportation systems and accommodations of developed countries (energies technically different from fossil or nuclear energies; fundamental energy sources for a developing world; different national goals in Europe depending on the available natural resources and on the political realities; a minor interest in France for the domestic power generation but a major interest ...

International Nuclear Information System (INIS)

This short article describes the strategies taken into consideration by the Swiss Federal Office of Energy for the promotion of renewable forms of energy in Switzerland. Two basic models are considered and the parts to be played by the Swiss Confederation, the Swiss Cantons, Energy Agencies and professional organisations are discussed. The importance of the activities of partner organisations and actor-networks in various areas such as solar, small hydro, geothermal and wind energy are discussed, as are models for financing the necessary promotion and marketing efforts

Energy Technology Data Exchange (ETDEWEB)

The US Department of Energy, Office of Technical and Financial Assistance (OTFA) promotes the application of renewable energy and energy efficiency technologies and practices by working cooperatively with state and local governments and private and nonprofit organizations, providing technical and financial assistance and serving as network for sharing information. This report is an overview of some of the programs designed to aid in solving our national energy problems.

Energy Technology Data Exchange (ETDEWEB)

Hydrogen has the potential to serve as both an energy storage means and an energy carrier in renewable energy systems. When renewable energy sources such as solar or wind power are used to produce electrical power, the output can vary depending on weather conditions. By using renewable sources to produce hydrogen, a fuel which can be stored and transported, a reliable and continuously available energy supply with a predictable long-term average output is created. Electrolysis is one method of converting renewable energy into hydrogen fuel. In this experiment we examine the use of an electrolyzer based on polymer-electrolyte membrane technology to separate water into hydrogen and oxygen. The oxygen is vented to the atmosphere and the hydrogen is stored in a small pressure vessel.

International Nuclear Information System (INIS)

Interest in renewable energy systems that employ regenerative components to enable intermittent energy sources to service time varying loads is growing. The overall performance of these systems is intimately linked to the choice of the energy storage media and the efficiency of the energy conversion devices. Recent advances in electrolyser and fuel cell technologies may make small-scale hydrogen buffered renewable energy systems a practical reality in the near term. A research team at the University of Victoria - Institute for Integrated Energy Systems (IESVic) is developing a flexible distributed, laboratory-scale energy system called IRENE (Integrated Renewable Energy Experiment). The initial goal of this research is to explore the potential for ...

Energy Technology Data Exchange (ETDEWEB)

Science and technology are at the heart of everything we do at the National Renewable Energy Laboratory, as we pursue innovative, robust, and sustainable ways to produce energy--and as we seek to understand and illuminate the physics, chemistry, biology, and engineering behind alternative energy technologies. This year's Research Review highlights the Lab's work in the areas of alternatives fuels and vehicles, high-performing commercial buildings, and high-efficiency inverted, semi-mismatched solar cells.

International Nuclear Information System (INIS)

High energy consumption and the world population increase will lead to a shrinking use of fossil fuels. The combustion of Fossil fuel leads to the increase of carbon dioxide concentration in the atmosphere which leads to the probable increase of global warming. Therefore, concerns about carbon dioxide emissions may discourage widespread dependence on fossil fuels and encourage the development and use of renewable energy systems employing a variety of technologies Renewable energy systems have themselves an environmental impact. Land use and material employed are two areas that may have an adverse impact to the positive environmental picture of the renewable energy systems. The objective of this paper is to analyze these impacts with the use of a very powerful tool, the Life Cycle Assessment. (author)

Energy Technology Data Exchange (ETDEWEB)

Encouragement and incentives ar being given in many counties to the electricity industry and private sector to install, own and operate renewable energy systems. The impact of renewable energy installations connected to the grid or operating independently is an important issue concerning the technical and economic viability of harnessing these emerging energy sources. This paper brings out the need for developing and implementing a strategy for comprehensive and accurate protection and control systems for these dispersed generator installations. It appears that a combination of discrete and fuzzy logic devices on an integrated platform will be a novel technique for the protection and control schemes. This development has the potential to be cost effective and suits the requirements for operating renewable energy systems safety. (author). 2 ...

Wastenet

...Climate Change : News Categories : Department of Energy and Climate Change Articles in Smart energy meters Results There are 2 articles listed in Smart energy ... meters DECC lays foundations for smart meters rollout A crucial step in delivering the UK's energy security and low carbon future was taken today ...Nuclear Prices Renewable energy Renewable Heat Incentive Saving energy and CO2 Science Smart energy meters Statistics Statistics and projections Transparency Wave and tidal Wind ...

Energy Technology Data Exchange (ETDEWEB)

This revised edition discusses a large number of renewable energy systems. Future trends are outlined. Economic efficiency calculations are explained and analyzed. Many exemplary calculations and graphical representations illustrate the various technologies and methods of calculation. This standard book addresses university students, scientists and engineers in research and industry. The accompanying DVD is one of the most extensive compilations of demo programs and full versions for simulation of renewable energy systems, all illustrations of the book in electronic format, additional text and a user-friendly navigation aid. (orig.)

Science.gov (United States)

Nonparabolicity of the heavy hole band in diamond-like semiconductors, which occurs within the framework of the three band model with the perturbation from the other bands taken into account according to the Loewdin procedure, is studied. A direct dependence of nonparabolicity on the band anisotropy (caused by the different effect of Gamma/sub 15c/ and Gamma/sub 12c/ bands) and the inverse dependence on the magnitude of the spin-orbit splittiing is established. A connection between the effective mass of heavy holes and their energy is obtained, which is valid for the majority of diamond-like semiconductors, except for materials with a very strong nonparabolicity of the band of silicon type

Science.gov (United States)

A Self-Powered Underwater Robot for Ocean Exploration and Beyond ... first unmanned underwater vehicle (UUV) that is completely powered by renewable energy . ...

Science.gov (United States)

Efficiency and Renewable Energy EERE Home | Programs & Offices | Consumer Information Chemicals Search Search Help Chemicals EERE » Industrial Technologies Program » Chemicals...

Science.gov (United States)

and Renewable Energy EERE Home | Programs & Offices | Consumer Information Geothermal Technologies Program Search Search Help Geothermal Technologies Program HOME ABOUT...

Energy Technology Data Exchange (ETDEWEB)

The Meteorological Service of Canada has made weather datasets available in real-time on the Internet, for use by those with an interest in solar applications. Ensemble weather models can be used to produce medium range forecasts of weather events and to predict the likely available kilowatt-hours (kWhrs) of solar energy. As such, solar sites can maximize their harvest and use of solar energy. This presentation highlighted several different types of renewable energy forecasts obtained from weather models, including forecasts of expected kWhrs from solar panels and wind turbines, daily forecasts of expected solar heated water volumes and forecasts of water collection potential from impending precipitation events. The value of renewable energy forecasts in helping the solar energy sector monitor daily energy loads as well ...

Energy Technology Data Exchange (ETDEWEB)

This presentation discussed common mechanisms for procuring wind energy in Canada. Mechanisms included renewable portfolio standards (RPSs); offsets; tax subsidies; financial subsidies; command and control mechanisms; and request for proposals (RFPs). A layered approach is required to avoid reliance on any single mechanism. RPSs require a certain minimum percentage of energy to come from renewable sources and aim to encourage the local development of renewable energy. RPSs are market-friendly and often result in the creation of tradable renewable energy credits (RECs) used for compliance purposes. RPSs work in parallel with cap and trade, baseline, and credit and carbon tax systems. RFPs target the lowest price offering, a practice which has often resulted in lower rates of return, high attrition, and a failure to ...

International Nuclear Information System (INIS)

This 2001 edition of the guide to UK renewable companies and equipment and service providers presents summaries of the different industry sectors covering wind power, photovoltaics, solar water heating, geothermal heat pump, hydroelectric power, marine current and wave technology, bioenergy, power generation from landfill gas, energy from waste, and cogeneration. A UK company classification listing and index is provided along with listing of UK organisations and companies and an index of advertisers.

Energy Technology Data Exchange (ETDEWEB)

Today, the analysis of renewable energy places the emphasis on the technological and economic attributes with social and environmental impact assessment providing for a rather static, narrow frame of analysis. The participation and response of social actors and other stakeholders is usually of a traditional type, with consultation documents and public meetings, collection of complaints and suggestion schemes. This often encourages parochialism and an over-concentration on relatively trivial issues. It is, therefore, imperative to establish a new participatory planning platform to incorporate the wider socio-economic aspects of renewable energy systems and to provide for an operational analytical decomposition of them. In this work the issue of decomposition analysis is clarified, and a new agenda for the societal and technological decomposition analysis of renewable ...

International Nuclear Information System (INIS)

In the rural areas, especially those located far enough from infrastructure facilities (highways and national roads, electricity and gas networks, etc.), energy supply (both quantitatively and qualitatively) is scarcer than in the urban ones. The purpose of this paper is to analyse the use of renewable energy hybrid systems in order to increase the quality and the quantity of energy supplied to the rural settlements. The paper is thus a guide of how to choose the appropriate energy source with higher potential and efficiency, minimal capital and operational costs and better comfort. (authors)

UK PubMed Central (United Kingdom)

All energy scenarios show a shift toward an increased percentage of renewable energy sources, including biomass. This study gives an overview of water footprints (WFs) of bioenergy from 12 crops that...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

Renewable energy technologies such as photovoltaics, solar thermal power plants, and wind turbines are nonconventional, environmentally attractive sources of energy that can be considered for electric power generation. Many of the areas with abundant renewable energy resources (very sunny or windy areas) are far removed from major load centers. Although electrical power can be transmitted over long distances of many hundreds of miles through high-voltage transmission lines, power transmission systems often operate near their limits with little excess capacity for new generation sources. This study assesses the available capacity of transmission systems in designated abundant renewable energy resource regions and identifies the requirements for high-capacity plant integration in selected cases. In general, about 50 MW of power from ...

International Nuclear Information System (INIS)

The authors present arguments against nuclear energy and pro renewable energy sources. Thus, the water used in Uranium mining and primary ore processing becomes contaminated in long lived radioisotopes and so a threat for local ecosystems and communities. Then, during the fabrication, enrichment, and handling of nuclear fuel the workers are exposed to radiations and dangerous accidental radioactive leaks can occur. But, by far, the most menacing aspect of nuclear power exploitation remains the human errors in operating the nuclear plants which can result in major accidents like that from Chernobyl which spread radioactivity all over the Europe. The equipment used in nuclear facilities which is highly contaminated as well as the burned fuel implies transportation and long term storage which also present high risks. The major advantage of the nuclear energy consists in its very low environment impact and ...

Energy Technology Data Exchange (ETDEWEB)

EREC, the international umbrella organization, published last year a study on export strategies for renewable energy technologies. The 150-page document provides valuable information on key export markets and financial institutions, and presents the various branches' perspectives for the future. The following excerpts will whet your appetite for more. The complete study is available for download: www.erec-renewables.org (Eurees). (orig.)

International Nuclear Information System (INIS)

An overall review of status of energy in Lebanon is presented. Energy consumption and demand, in all sectors of economy, including renewable energy sources (biomass, solar energy, kerosene, gas oils...) are described, enhanced by figures and tables. Recommendations of energy development in Lebanon within national economic policy are formulated. 4 tabs.

Energy Technology Data Exchange (ETDEWEB)

This report deals with the renewable energies and the local development called the territory intelligence in action. Taking into account the place of the electricity in the french energy accounting and the part of the nuclear in its production, the local authorities have to act in the heat domain, which is the first energy need in France, far in front of the specific electricity (those which cannot be replace by other type of energy). But 80% of the heat is today covered by fossil energies. No actions to change this situation will be done without a real implication of the local government. The authors preconize an ambitious objective: cover 50% of the heat needs from renewable energies in the next generat This objective must rely on a program called ''alternative ...

Energy Technology Data Exchange (ETDEWEB)

This report describes and analyzes renewable energy seen as emerging markets, focusing on wind, solar and wave power. The conclusions are that: Wind and solar energy has reached critical mass. They are already large markets, and has a high growth rate. There are growth areas that may become among the world's largest industries in the future. This summary report and the underlying studies of wind, solar and wave power show that there is a large potential market for renewable energy sources. Wind power is already a market worth around 36.5 billion Euro. Solar energy is growing strongly and solar cells in 2008 had a market worth around 24 billion Euro. Wave power is at present a very small market and the in the actual development stage the potential of wave power is uncertain. But if the wave would become commercially viable, it could represent a ...

Energy Technology Data Exchange (ETDEWEB)

This article examines reported willingness to pay for electric utility investments in renewable energy and energy efficiency resources using the results of Deliberative Polls conducted by electric utilities in Texas. Age, education, and salary tend to affect reported willingness to pay for utility investments in these resources. Intensive exposure to information about energy resource issues led to an increase in the number of respondents interested in paying a modest premium to support investments in both renewable energy resources and energy efficiency. However, average reported premiums actually declined following the Polls, as very high outlier responses moved to more reasonable values following the Polls. These results support the contention that informed dialogue about energy alternatives will result in broader ...

International Nuclear Information System (INIS)

The economics of renewable energy are the largest barrier to renewable penetration. Nevertheless, the strong desire to reduce environmental emissions is considered a great support for renewable energy sources. In this paper, a full analysis for the cost of the kWh of electricity generated from different systems actually used in Egypt is presented. Also renewable energy systems are proposed and their costs are analyzed. The analysis considers the external cost of emissions from different generating systems. A proposed large scale PV plant of 3.3 MW, and a wind farm 11.25 MW grid connected at different sites are investigated. A life cycle cost analysis for each system was performed using the present value criterion. The comparison results showed that wind energy generation has the lowest cost, followed by a combined ...

International Nuclear Information System (INIS)

High and volatile natural gas prices have increasingly led to calls for investments in renewable energy. One line of argument is that deployment of these resources may lead to reductions in the demand for and price of natural gas. Many recent US-based modeling studies have demonstrated that this effect could provide significant consumer savings. In this article we evaluate these studies, and benchmark their findings against economic theory, other modeling results, and a limited empirical literature. We find that many uncertainties remain regarding the absolute magnitude of this effect, and that the reduction in natural gas prices may not represent an increase in aggregate economic wealth. Nonetheless, we conclude that many of the studies of the impact of renewable energy on natural gas prices appear to have represented this effect within reason, given current knowledge. These studies specifically ...

International Nuclear Information System (INIS)

Energy band diagrams of LaCuOCh (Ch = S, Se and Te) were calculated by a full-potential linearized augmented plane-wave method. The calculations, based on the local density approximation with/without an on-site Coulomb repulsion parameter, were to examine the energy levels of La 4f states. The results of the calculations showed that the on-site correlation parameter is necessary for evaluating the energy levels of La 4f states appropriately. The calculations for LaCuOCh with the on-site correlation parameter revealed that LaCuOS and LaCuOSe have almost the same energy band structure with a direct allowed-type band gap, while LaCuOTe has significantly different conduction band structure that exhibits an indirect-type band gap. This difference in electronic structure between LaCuOCh (Ch = S, Se and Te) ...

Energy Technology Data Exchange (ETDEWEB)

A method based on cluster analysis techniques is proposed in order to obtain representative local wind patterns. Modeling renewable energy systems, in an accurate way which strongly depends on wind loads, requires reliable data to analyze their response and evaluate their performance. Otherwise poor agreement with the models may be obtained. In a case study for La Paz, Baja California Sur, Mexico, four different wind patterns were obtained from a one-year data set recorded at 10-min intervals. (author)

International Nuclear Information System (INIS)

The UK Energy Research Centre (UKERC) in it's submission to the DTI's 2006 Energy Review reminded us that the 'UK has abundant wind, wave and tidal resources available; its mild climate lends itself to bio-energy production, and solar radiation levels are sufficient to sustain a viable solar industry'. These technologies are at different stages of development but they all draw on basic and applied Science and Engineering. The paper will briefly review the renewable energy technologies and their potential for contributing to a sustainable energy supply. Three research topics will be highlighted that bridge the gap between the physics underpinning the energy conversion, and the engineering aspects of development and deployment; all three are highly relevant to the Government's programme on micro-generation. Two are these are taken from field ...

Energy Technology Data Exchange (ETDEWEB)

Remote Alaskan communities pay economic and environmental penalties for electricity, because they must import diesel as their primary fuel for electric power production, paying heavy transportation costs and potentially causing environmental damage with empty drums, leakage, and spills. For these reasons, remote villages offer a viable niche market where sustainable energy systems based on renewable resources and advanced energy storage technologies can compete favorably on purely economic grounds, while providing environmental benefits. These villages can also serve as a robust proving ground for systematic analysis, study, improvement, and optimization of sustainable energy systems with advanced technologies. This paper presents an analytical optimization of a remote power system for a hypothetical Alaskan village. The analysis considers the potential of generating renewable ...

International Nuclear Information System (INIS)

The first-order relativistic correction to the kinetic energy of an electron, the mass-velocity term, is not bounded from below. It can, therefore, not be used within a variational framework. To overcome this deficiency we developed a method to include the entire relativistic kinetic energy #sq root#(p"2c"2+m_0"2c"4)-m_0c"2 in a spline-augmented plane-wave band calculation. The first results for silver are quite promising, especially for d and p states: The analysis of the energies of the core states as well as of the valence band structure suggests that the energies of d bands are reproduced within 1 mRy. However, the combination of the relativistic kinetic energy with the Darwin term leads to energies which are too low for s-like valence states by 10 mRy. Therefore, the s and d valence ...

Energy Technology Data Exchange (ETDEWEB)

The Advanced Power Electronics Interfaces for Distributed Energy Workshop, sponsored by the California Energy Commission Public Interest Energy Research program and organized by the National Renewable Energy Laboratory, was held Aug. 24, 2006, in Sacramento, Calif. The workshop provided a forum for industry stakeholders to share their knowledge and experience about technologies, manufacturing approaches, markets, and issues in power electronics for a range of distributed energy resources. It focused on the development of advanced power electronic interfaces for distributed energy applications and included discussions of modular power electronics, component manufacturing, and power electronic applications.

Energy Technology Data Exchange (ETDEWEB)

Subsurface and surface coalfires are a serious problem in many coal-producing countries. Combustion can occur within the coal seams (underground or surface), in piles of stored coal, or in spoil dumps at the surface. While consuming a non renewable energy source, coalfires promote several environmental problems. Among all GHGs that are emitted from coalfires, CO2 is the most significant because of its high quantity. In connection to this environmental problem, the core aim of the present research is to develop a hyperspectral remote sensing and radiative transfer based model that is able to estimate CO2 concentration (ppmv) from coalfires. Since 1960s remote sensing is being used as a tool to detect and monitoring coalfires. With time, remote sensing has proven a reliable tool to identify and monitor coalfires. In the present study multi-temporal, multi-sensor and multi-spectral thermal remote sensing data are being used to detect and monitor ...

Energy Technology Data Exchange (ETDEWEB)

Using Gammasphere data on prompt gamma rays from spontaneous fission of 252Cf, we propose energy-level schemes for 110,111,112, & 113Rh (Z=45). The fission-gamma data complement earlier studies of others on beta decay of fission products in that prompt fission gammas mainly populate yrast or near-yrast levels, while beta decay populates lower-spin levels. For the odd-A rhodium nuclei studied here, their ground bands and collective sidebands are compared with model calculations using triaxial-shaped nucleus with one odd quasi-proton. The energies and E2 transition rates are best fit by a shape slightly to the prolate side of maximum triaxiality, namely, gamma = 28 deg. The model calculations also show a K=1/2+ band with energies not in good agreement with a corresponding experimental band. The experimental 1/2+ band is regarded as an ...

Energy Technology Data Exchange (ETDEWEB)

The energy challenges of the next 30 years appear daunting and, in certain cases, in conflict with one another. Their complexity is such that one solution alone cannot provide a full answer. It is nevertheless equally clear that hydro-electricity, being renewable, proven, highly efficient, storable and with still very significant resource potential, possesses a unique combination of attributes which will aid decision-makers to plan and execute energy development with confidence.

Energy Technology Data Exchange (ETDEWEB)

The interaction of thermal radiation with conduction and convection in thermally developing absorbing, emitting, nongray gas-particulate turbulent suspension flow through a circular tube is investigated. The contribution of thermal radiation is obtained through evaluation of the total hemispherical emittance of the particulate cloud and through evaluation of single band absorptances for molecular gases, modified to account for the interaction with the particles. The governing differential equation is derived as a (nonlinear) energy equation, coupled with integral equations to find the thermal radiation contributions. The energy equation is solved numerically by an implicit finite difference method with an iterative procedure. Qualitative results for Nusselt numbers are shown for a variety and range of parameters, such as optical thickness of particulates and single molecular gas bands, relative gas ...

Energy Technology Data Exchange (ETDEWEB)

This paper reported on a study that was conducted in Japan to determine whether renewable energy generated from snow can be used to replace the cooling system and electricity used for cooling a rice storehouse that maintained the grain temperature below 15 degrees C. However, the low-temperature storage system required a cooling system and electricity to cool rice in summer. In this study, a snow pile using 890 t of snow was made at the beginning of March next to the rice storehouse. The shape of the snow pile was a trapezium, 17 x 23 m at the bottom and 4 x 10 m at the top and 5 m in height. The snow pile was covered with 200 to 300 mm of wood chips to act as an insulation layer. Approximately 27 per cent of the energy for cooling the rice storehouse could be replaced by using the snow pile in summer. The quality of stored rice was almost similar to that of freshly harvested rice. The study showed that ...

Energy Technology Data Exchange (ETDEWEB)

The purpose of this research was to develop a methodology for sizing integrated renewable energy systems, useful for rural areas, using simulation and optimization tools developed in MATLAB 6.0. The sizing model produces a system with minimum cost and high reliability level, based on the concept of loss of power supply probability (LPSP) for consecutive hours. An optimization model is presented and three different sizing scenarios are calculated and compared, showing flexibility in the elaboration of different project conceptions. The obtained results show a complete sizing of the energy conversion devices and a long-term cost evaluation. (author)

International Nuclear Information System (INIS)

An attempt to develop a simple framework for financial evaluation of renewable energy technologies (RETs) such as photovoltaic (PV) pump, windmill pump, biogas and producer gas-driven dual fuel engine pumps for irrigation water pumping has been made. The unit cost of water and unit cost of useful energy delivered by the RETs have been estimated. The monetary benefits that accrued to the end-user have been quantified in terms of the amount of diesel or electricity saved. Financial figures of merit for the investments made in the RETs have been estimated. The effect of fuel price escalation on these measures of financial performance has also been evaluated along with the estimation of the break-even prices of fuels likely to be substituted by RETs. Results of some exemplifying calculations are presented and briefly discussed.

Energy Technology Data Exchange (ETDEWEB)

A strong dependence of thermal activation energy (TAE) on infrared (IR) stimulation time for the infrared stimulated luminescence (IRSL) signal was observed for K-feldspar grains extracted from several sediments and granites from China. A TAE value as low as {approx}0.1 eV was observed at the beginning of IR stimulation and increased to {approx}0.45 eV after 90 s. For a trap depth of {approx}2 eV below the conduction band for the IRSL traps, the TAE value of {approx}0.45 eV is consistent with the energy gap between the excited states ({approx}0.5 eV below the conduction band) and conduction band. This phenomenon is explained as the result of the coexistence of thermally assisted recombination via conduction band or band-tail states hopping and athermal tunnelling recombination of electrons from the excited states under IR stimulation, ...

Energy Technology Data Exchange (ETDEWEB)

This sheet summarizes information on geothermal heat pumps (GHPs), which extracts heat from the ground in the winter and transfers heat to the ground in the summer. More than 200,000 GHPs are operating in US; they can reduce energy consumption and related emissions by 23 to 44% compared to air-source heat pumps. Opportunities for use of GHPs, requirements, and cost are described. Important terms are defined.

Energy Technology Data Exchange (ETDEWEB)

Revolving type fluidized-bed technology, developed by Ebara Corp., is installed in more than 100 facilities worldwide. The technology is applied for waste, coal and in situations where a conventional fluidized bed is difficult to use. Waste and/or coal can be treated and valuable energy can be recovered from a non-renewable source. This paper describes the application of the revolving fluidized bed for waste, coal and tyres.

Energy Technology Data Exchange (ETDEWEB)

We study two correlated electrons in a nearest-neighbour tight-binding chain, with both on-site and nearest-neighbour interaction. Both the cases of parallel and antiparallel spin are considered. In addition to the free electron band for two electrons, there are correlated bands with positive or negative energy, depending on whether the interaction parameters are repulsive or attractive. Electrons form bound states, with amplitudes that decay exponentially with separation. Conditions for such states to be filled at low temperatures are discussed.

DEFF Research Database (Denmark)

Interest in optics for hard X-ray broad-band application is growing. In this paper, we compare the hard X-ray (20-100 keV) reflectivity obtained with an energy-dispersive reflectometer, of a standard commercial gold thin-film with that of a 600 bilayer W/Si X-ray supermirror. The reflectivity of the multilayer is found to agree extraordinarily well with theory (assuming an interface roughness of 4.5 Angstrom), while the agreement for the gold film is less, The overall performance of the supermirror is superior to that of gold, extending the band of reflection at least a factor of 2.8 beyond that of the gold, Various other design options are discussed, and we conclude that continued interest in the X-ray supermirror for broad-band hard X-ray applications is warranted.

International Nuclear Information System (INIS)

High-spin states (I < or approx. 50(#Planck constant#/2#pi#)) of the odd-odd nucleus "1"7"0Ta have been investigated with the "1"2"4Sn("5"1V,5n) reaction. The resolving power of Gammasphere has allowed for the observation of eleven rotational bands (eight of which are new) and over 430 transitions (#approx#350 of which are new) in this nucleus. Many interband transitions have been observed such that the relative spins and excitation energies of the 11 bands have been established. This is an unusual circumstance in an odd-odd study. Configurations have been assigned to most of these bands based upon features such as alignment properties, band crossings, B(M1)/B(E2) ratios, and the additivity of Routhians. A systematic study of the frequency at which normal signature ordering occurs in the #pi#h_9_/_2#nu#i_1_3_/_2 band has been performed and it is found that ...

Energy Technology Data Exchange (ETDEWEB)

The French agency of environment and energy mastery (Ademe) and Deutsche Energie Agentur (DENA) organised in Berlin on November 22 and 23, 2001, the first seminar and forum of ideas and exchanges on the implementation of energy efficiency and renewable energy policies in France and in Germany. On this occasion, Ademe asked Energie-Cites - an association of European cities with a long practical experience in 'good practice' exchanges - to prepare a publication describing the experience of about ten French cities or local energy agencies in energy management issues. The case studies presented in this document concern the following cities: Besancon, Dole, Dunkerque, Lille, Montpellier, and the local energy agencies of Clermont-Ferrand (Aduhme), Grenoble, Montreuil-Vincennes, Mulhouse ...

Energy Technology Data Exchange (ETDEWEB)

This report contains a partial catalog of recent accomplishments of the U.S. Department of Energy's Office of Energy Efficiency and Renewable Energy (EERE)in collaboration with its many private- and public-sector partners. This compendium of success stories illustrates the range and diversity of EERE programs and achievements. Part of an ongoing effort, the principal goal of this collection is to provide stakeholders with the evidence they need to assess the value they are receiving from investments in these DOE programs. The report begins with an introduction and a description of the methodology. It then presents an overview of the accomplishments of EERE programs. This is followed by the stories themselves.

DEFF Research Database (Denmark)

Wind power is a maturing technology that in a number of countries is likely to contribute a major share to fully renewable energy systems. Denmark has a comparably long history of wind power development and is planning to continue expanding the existing capacity. If a large-scale penetration of wind power is to be achieved, an integrated framework is needed that can respond to the associated challenges. This paper argues for adopting an integrated macro perspective when evaluating and building frameworks to support wind power development. This macro perspective is applied to the case of Denmark, and more specifically to concrete wind power projects in the region of Northern Jutland. The results suggest although certain elements in the legislation have been improved, the feasibility of wind power projects cannot be guaranteed, and there is a tendency to exclude smaller turbines from the development.

Energy Technology Data Exchange (ETDEWEB)

Proposed features of the competitive electricity market in Ontario were reviewed. The speaker predicted that demand for renewable energy in Ontario`s competitive electricity market will be affected by green power, emissions trading, labelling, and renewables portfolio standard. Under current regulations retailers can charge customers a premium for purchasing electricity generated by `green` sources. The existing limits on emissions of sulphur dioxide, nitrogen oxides and carbon dioxides will remain in place, but an emissions cap and trading program for all Ontario-based generation is an option to consider. Ontario`s Market Design Committee (MDC) has recommended the implementation of emissions trading for electricity-related air pollutants for all generators located in Ontario. The complex mechanics of emission trading are explained. The MDC recommendation of the use of standard labels to disclose the mix of ...

Energy Technology Data Exchange (ETDEWEB)

Estonia is rich in such renewable energy sources like wood, peat and wind. Wind energy potential is very high (up to 7 TWh) due to its geographical location. Wind potential could be efficiently used particularly on the western coast and on islands. Wider use of renewable energy sources would allow significant cutting of GHG emissions. Wind energy yield reaches up to 9000 MWh in West-Estonian Archipelago, 4000-8000 MWh in other coastal regions and up to 4000 MWh in inland areas per 2 MW wind turbine. In Estonian coastal regions (20 km wide zone along the 3800 km long coastline) there is 114 000 ha (7.9% of total area) open fields that are fully suitable for harnessing wind energy. Use of wind energy has been hindered so far mainly by a systematic under-capacity operation of two large oil shale power plants in Narva and ...

Energy Technology Data Exchange (ETDEWEB)

Rapid growth in economic development, coupled with the absence of an electric grid in large areas of the rural countryside, have created a need for new energy sources both in urban centers and rural areas in China. Environmental pollution from the increased use of coal-fired steam turbines to meet this capacity expansion is a concern. There is a growing interest in China to develop renewable-energy resources and technologies to meet energy demands and help mitigate pollution problems. In February 1995, Secretary Hazel O`Leary of the U.S. Department of Energy signed an Energy Efficiency and Renewable Energy Protocol Agreement with the Chinese State Science and Technology Commission in Beijing, China. Under this agreement, projects using photovoltaics for rural electrification are being conducted in Gansu Province in western China and Inner ...

International Nuclear Information System (INIS)

We report a detailed augmented-plane-wave energy-band study and wave-function analysis of stoichiometric PdH which shows that, even though the Fermi surface of PdH is qualitatively similar to that of silver, the simple ''proton model'' is not valid. Instead, the screening of the proton in PdH is found to be larger than in an isolated H atom due, in part, to the formation of a H-Pd bonding band below the bottom of the d-band complex. This result, which is in qualitative agreement with Switendick's earlier calculation, is confirmed by ultraviolet photoemission experiments. A partial density-of-states (DOS) analysis in the energy range spanned by the six valence and conduction bands reveals the quantitative details of the bonding mechanism between the Pd and H constituents. At the Fermi energy, the high Pd d to H s DOS ratio approx. 10.3 is found to be far higher ...

International Nuclear Information System (INIS)

Ab initio calculations of the electronic structure were performed for the silver palladium oxide, Ag_2PdO_2, by the full potential mixed linearized augmented plane wave and augmented plane wave plus local orbitals method (mixed LAPW/APW+lo) within the density functional theory and using the generalized gradient approximation (GGA96, Phys. Rev. Lett. 77 (1996) 3865) for the exchange-correlation potential. The lattice parameters were calculated from the ground-state total energy versus volume curve, and are in good agreement with the available experimental results. Our calculations of band structure predicted that the compound Ag_2PdO_2 has indirect band gap, and the Pd 4d states strongly hybridize with the O 2p states all over the valence bands and conduction bands. The valence bands are composed mainly of Ag, Pd 4d states and O 2p states, while the conduction ...

Energy Technology Data Exchange (ETDEWEB)

The group- V vacancy pair, the so-called E-center, has recently been demonstrated to have, both in Si and Ge, more complicated energy-level schemes in the energy gap than were previously assumed. The E-center in silicon has, in addition to its well-established single-acceptor level in the upper half of the band gap, also a donor level in the lower half of the band gap; this donor level has lain hidden for more than 40 years. The E-center in Ge has an even more complicated level scheme as it induces, in addition to two levels analogous to those found in Si, also a double-acceptor level in the upper half of the band gap. Thus the E-center in Si can exist in three charge states and the E-center in Ge in four.

International Nuclear Information System (INIS)

The magnon dispersion curve of Gd metal has been determined from first principles by use of augmented-plane-wave energy bands and wave functions. The exchange matrix elements I (k,k') between the 4f electrons and the conduction electrons from the first six energy bands were calculated under the assumption of an unscreened Coulomb interaction. The results are in good overall agreement with experiment provided the I (k,k') are diminished by a constant scale factor of about 2 which may be caused by screening.

Energy Technology Data Exchange (ETDEWEB)

Today's building industry is promoting the use of renewable sources of energy to heat, cool, and illuminate commercial buildings. Societies such as the International Solar Energy Society sponsor conferences such as this one to share knowledge and experience in the area of solar energy. However, the technologies presented here assume a need for heating, cooling or illumination. A simple technique is presented for determining the actual heating, cooling, and lighting requirements for commercial buildings, and for reducing those requirements through proper building design before applying solar technologies. The energy nomographs are a graphic energy design tool developed to aid designers in making cost effective decisions about energy alternatives early in the design process. Reducing loads at this point can help reduce the expense of ...

Energy Technology Data Exchange (ETDEWEB)

Deregulation of the electric power industry in Alberta holds the prospect of providing greater choice for customers. One such option will be `green power` which is provided by renewable energy technologies. The energy produced would be without environmental impacts such as air emissions, water pollution, flooding, thermal emissions or waste by-products. Wind power, small scale hydro power, photovoltaics and biomass technologies have been termed as `green power`. The choices that customers make will not be focused on price alone. Market forces are emerging to demand reduction in emissions which will result in a market for `green energy` products and facilitate achieving goals for a sustainable future.

Energy Technology Data Exchange (ETDEWEB)

As in the years before, the situation of steam boiler engineering was characterized by the following influencing parameters: Slow increase in electric power consumption; enhanced controversy over the CO{sub 2} emissions of fossil-fuel combustion; controversy over nuclear power; too much enthusiasm about the applications of additive and renewable energy. In all, six turbines with capacities over 100 MW were started but only one turbine of 180 MW was newly ordered. (orig./GL).

Energy Technology Data Exchange (ETDEWEB)

The National Renewable Energy Laboratory (NREL) evaluated the performance of diesel, compressed natural gas (CNG), and hybrid electric (equipped with BAE Systems? HybriDrive propulsion system) transit buses at New York City Transit (NYCT). CNG, Gen I and Gen II hybrid electric propulsion systems were compared on fuel economy, maintenance and operating costs per mile, and reliability.

Energy Technology Data Exchange (ETDEWEB)

This 2001 edition of the guide to UK renewable energy companies examines the geothermal heat pump sector, and discusses the technology involved, installations of geothermal heat pumps, the activity in the UK market with increased interest in UK geothermal heat pump products from abroad, and developments in the building sector. The UK government's increased support for the industry including its sponsorship of the Affordable Warmth programme, and the future potential of ground source systems are discussed.

Science.gov (United States)

I travelled to San Jose, Costa Rica on July 8, 1990 to evaluate all of the completed elements of the ongoing feasibility study for the San Lorenzo River hydroelectric project. The feasibility study is being supported by ORNL under the Renewable Energy Applications and Training Project. The project is being studied for implementation by CONELECTRICAS, a consortium of rural electric cooperatives and the study itself is being conducted by BEL Engineering, a Costa Rican consulting firm under contract to CONELECTRICAS, USAID/PIC and NRECA.

British Library Electronic Table of Contents (United Kingdom)

Within the current outlook for sustainable electric energy supply with concomitant reduction in emission of greenhouse gases, accelerated attention is focusing on the long-term development of hydrogen fuel cell and all-electric battery vehicles to provide alternative fuels to replace petroleum-derived fuels for automotive national fleets. The potential varies significantly between large industrially developed nations and smaller industrially developing nations. The requirement for additional electric energy supply from low-specific energy renewable resources and high-specific energy nuclear resources depends strongly on individual national economic, environmental, and political factors. Analysis of the additional electric energy supply required for the two potential large-scale technologie...

Energy Technology Data Exchange (ETDEWEB)

Most of the information in this chapter is obtained from 1, 2, 3, 6, 8 and 9 annexes. It is worthwhile to clarify that in most of the cases they are estimations of the available resources, such as: trash, geothermal, solar energy, wind energy, biomass and mini and micro-hydro-energy. In several cases punctual measurements have been made, which do not represent a generic value of a national reserve. [Spanish] La mayor parte de la informacion en este capitulo es obtenida de los anexos 1, 2, 3, 6, 8 y 9. Cabe aclarar que en la mayoria de los casos son estimaciones de los recursos disponibles, tales como: la basura, la geotermia, la energia solar, la energia eolica, la biomasa y, la mini y la micro-hidroenergia. En varios casos se han realizado mediciones puntuales, las cuales no representan un valor generico de una reserva nacional.

International Nuclear Information System (INIS)

Accurate full-potential self-consistent linearized augmented-plane-wave (FLAPW) calculations have been carried out for hexagonal boron nitride. The resulting energy-band structure indicates that this material is an indirect-gap insulator and shows the existence of two unoccupied interlayer bands, similar to those found in graphite and graphite intercalation compounds. Chemical bonding is mainly covalent, with a small charge transfer towards the nitrogen atoms. Moreover, model-potential calculations, based on first-principles FLAPW wave functions and potentials, have been used to study slabs of thickness up to 35 layers. Contrary to the case of graphite, our results do not provide evidence of surface states associated with the interlayer bands.

Energy Technology Data Exchange (ETDEWEB)

This paper summarizes the U.S. Department of Energy R&D program in crystalline-silicon photovoltaic technology, which is jointly managed by Sandia National Laboratories and National Renewable Energy Laboratory. This program features a balance of basic an d applied R&D, and of university, industry, and national laboratory R&D. The goal of the crystalline-silicon R&D program is to accelerate the commercial growth of crystalline-silicon photovoltaic technology, and four strategic objectives were identified to address this program goal. Technical progress towards meeting these objectives is reviewed.

Energy Technology Data Exchange (ETDEWEB)

This paper presents an analysis of the performance of a selective emitter using small particles of rare earth compounds stable at high temperatures in a low emittance inert gas stream. An expression for the spectral emissive power excluding radiation scattering was derived to include the radiation in the emission band, produced by electronic transitions of the rare earth ion, and the continuum radiation outside the emission band produced by the rare earth host. Preliminary results suggest that a selective emitter based on suspended rare earth oxide particles will have high efficiency and merits further experimental investigation. {copyright} {ital 1996 American Institute of Physics.}

Energy Technology Data Exchange (ETDEWEB)

The Department of Energy (DOE) Office of Energy Efficiency and Renewable Energy (EERE) is interested in assessing the potential economic impacts of its portfolio of subprograms on national employment and income. A special purpose version of the IMPLAN input-output model called ImBuild II is used in this study of all 21 Building Technologies Program subprograms in the EERE final FY 2005 budget request to the Office of Management and Budget on February 2, 2004. Energy savings, investments, and impacts on U.S. national employment and earned income are reported by subprogram for selected years to the year 2030. Energy savings and investments from these subprograms have the potential of creating a total of 396,000 jobs and about $5.6 billion in earned income (2003$) by the year 2030.

International Nuclear Information System (INIS)

Thermoacoustics deals with the conversion of heat energy into sound energy and vice versa. It is a new and emerging technology which has a strong potential towards the development of sustainable and renewable energy systems by utilizing waste heat or solar energy. Although simple to fabricate, the designing of thermoacoustic devices is very challenging. In the present study, a comprehensive design and optimization algorithm is developed for designing thermoacoustic devices. The unique feature of the present algorithm is its ability to design thermoacoustically-driven thermoacoustic refrigerators that can serve as sustainable refrigeration systems. In addition, new features based on the energy balance are also included to design individual thermoacoustic engines and acoustically-driven thermoacoustic refrigerators. As a case study, a thermoacoustically-driven ...

International Nuclear Information System (INIS)

A link is made in this paper between proposed low energy scenarios for different Western European countries and the amount of pollutants that may result from these scenarios. Air pollutant emissions are calculated for the ten countries for which low energy scenarios are available. These scenarios emphasize stringent energy efficiency, maximizing the use of renewable (other than nuclear) energy, and minimizing the use of fossil fuels. Under these low energy scenarios, the average per capita energy use (year 2030) in the ten countries is estimated as 97 GJ/person, which is a decrease of 38% relative to 1980. Using the energy consumption figures from the low energy scenarios, together with sector- and fuel-specific emission factors from Europe, the resulting emissions of SO_2 , NO_x , and CO_2 were ...

Energy Technology Data Exchange (ETDEWEB)

Johnson & Johnson has had a formal energy program since the early 1970`s. A corporate energy department was formed as a result of the disruption of energy supplies and rising energy costs. Johnson & Johnson is a decentralized company with many independent operating companies throughout the world. The corporate energy department cuts across the different levels of management to delivery energy related information to the actual implementers at all of our locations worldwide. Like many other energy programs, Johnson & Johnson`s program had highs and lows depending on worldwide energy activities. Unlike many other corporate programs that were disbanded in the late 1980`s, our program remained in place, although there was not a high level of interest or attention. In the early 1990`s, the link was made between ...

International Nuclear Information System (INIS)

We studied the influence of alloying on the structural and electronic properties of the unrelaxed and relaxed Si_1_-_yC_y random alloys by means of ab initio theoretical calculations using two methods: (i) a supercell approach in connection with the plane-wave pseudopotential method; (ii) the full-potential augmented plane-wave plus local orbitals (APW+lo) method. The first method is used to obtain the relaxed atomic structure. The relaxed atomic positions obtained by pseudopotential calculations were used to calculate the band structure via the second method. The local density approximation was used for the exchange and correlation energy density functional. We investigated the lattice parameters and band gap energies. We found that a quite smaller gap appears in the neighborhood of y=0.03125 concentration of C atoms. The band gap shows a large anomalous bowing and is strongly ...

Energy Technology Data Exchange (ETDEWEB)

Biogas, produced from anaerobic digestion of organic matter in domestic, industrial and rural wastewaters and residuals, represent an alternative and renewable source of energy, with growing use worldwide. In Brazil, high population and its spatial concentration and expressive agricultural and agricultural-industrial production indicate a substantial potential of biogas production. The results presented in this work show a potential of biogas production of almost 2 billion cubic feet a day of CH{sub 4}. Viability of biogas production and use depends substantially on project scale. Generally, biogas projects are viable from landfills and domestic wastewater treatment for populations higher than 50,000 inhabitants and swine and dairy farms with at least 5,000 and 1,000 animals, respectively. Biogas is also competitive when compared to fossil fuels used in industry and transport. Despite incentive mechanisms for biogas production and use, like ...

Energy Technology Data Exchange (ETDEWEB)

Historically, the bulk production of electricity has been achieved by burning fossil fuels, with unavoidable gaseous emissions, including large quantities of carbon dioxide: an average-sized modern coal-burning power station is responsible for more than 10 Mt of CO{sub 2} each year. This paper details typical emissions from present-day power stations and discusses the options for their reduction. Acknowledging that the cuts achieved in the past decade in the UK CO{sub 2} emissions have been achieved largely by fuel switching, the remaining possibilities offered by this method are discussed. Switching to less-polluting fossil fuels will achieve some measure of reduction, but the basic problem of CO{sub 2} emissions continues. Of the alternatives to fossil fuels, only nuclear power represents a zero-carbon large-scale energy source. Unfortunately, public concerns over safety and radioactive waste have still to be assuaged. Other approaches include the application of ...

International Nuclear Information System (INIS)

The effects of hydrostatic pressure on the electronic band structure of the semiconductor mineral iron pyrite FeS_2 have been investigated theoretically by an ab initio full-potential linearized-augmented plane wave (FPLAPW) method within a local approximation (LDA/GGA) to the density functional theory. The calculations predict that at a pressure of 94.1 GPa the indirect band gap of pyrite FeS_2 vanishes and the material becomes a metal. This is due to the presence of the S-S and Fe-S bonds, which provide novel energy band distortions in the process of attaining the metallic state. Analysis indicates that, under increasing high pressure, the conduction bands (3p_z of sulfur and 3d_x_"2_-_y_"2+3d_x_y of iron) intrude downwards into the valence bands, which are predominantly 3d in nature. At normal pressure, the lattice constant, the bulk modulus, sulfur position ...

International Nuclear Information System (INIS)

The electronic structure of octahedral metal atom clusters Me_6 of 3d, 4d, and 5d transition metal atoms (V, Cr; Nb, Mo; Ta, W) has been calculated applying two different quantum-chemical approximation methods (Extended Hueckel (EH) method; SW-Xsub(alpha) method). Equilibrium structures, energy level schemes, Fermi energies and band widths as well as densities of states of clusters are discussed in detail.

Energy Technology Data Exchange (ETDEWEB)

Due to the recent catastrophic energy system failures in California along with those in the North-Eastern US and Southern Canada, London, and Italy, the time has come to proclaim the failure of deregulation, privatization or liberalization and propose a new energy system. This book shows in the first section, how five precipitating forces led to the deregulation debacle in California: (1) major technological changes and commercialization, (2) regulatory needs mismatched to societal adjustments, (3) inadequate and flawed economic models, (4) lack of vision, goals, and planning leading to energy failures, and (5) failure and lack of economic regional development. The second half of the book, examines how 'civic market', new economic models, and planning for complexity as sustainable economic development transformed in California, the same five forces to create an 'agile energy ...

International Nuclear Information System (INIS)

Environmental and security concerns are stimulating global interest in hydrogen power, renewable energy, and advanced transportation technologies, but no significant movement away from oil and a carbon-based world economy is expected soon. Over the longer-term, however, a transition from fossil fuels to a non-carbon-based economy will likely occur, affecting the type of environment future generations may encounter. Key challenges will face the world's energy industry over the next few decades to ensure a smooth transition-challenges which will require government and industry solutions beginning as early as today. This paper identifies four critical challenges in energy and the choices which will have to be made on how best to confront growing pollution caused by fossil fuels and how to facilitate an eventual revolutionary-like transition to a non-carbon-based global economy.

Energy Technology Data Exchange (ETDEWEB)

The emergence of new power electronics and improved battery technology has created renewed interest in Battery Energy Storage Systems (BESS). These new systems provide electric utilities with alternatives to conventional storage technologies, such as pumped hydro. BESs has the potential to provide substantial benefits in terms of energy management, improved voltage, spinning reserve and protection from interruptions when compared to large centralized storage. This paper describes a commercial, economically justified, application of the new Battery Energy Storage Systems which is presently under construction in the Metlakatla Power and Light system. The paper outlines the system performance requirements which lead to consideration of BESS as an option; the economic factors which provided the justification for BESS as an economic alternative; and the overall BES system design and performance.

International Nuclear Information System (INIS)

We present a comprehensive, up-to-date compilation of band parameters for the technologically important III - V zinc blende and wurtzite compound semiconductors: GaAs, GaSb, GaP, GaN, AlAs, AlSb, AlP, AlN, InAs, InSb, InP, and InN, along with their ternary and quaternary alloys. Based on a review of the existing literature, complete and consistent parameter sets are given for all materials. Emphasizing the quantities required for band structure calculations, we tabulate the direct and indirect energy gaps, spin-orbit, and crystal-field splittings, alloy bowing parameters, effective masses for electrons, heavy, light, and split-off holes, Luttinger parameters, interband momentum matrix elements, and deformation potentials, including temperature and alloy-composition dependences where available. Heterostructure band offsets are also given, on an absolute scale that allows any material to be aligned ...

International Nuclear Information System (INIS)

The high-spin structure of the Z=77 nucleus "1"8"7Ir has been studied using the fusion-evaporation reaction "1"8"6W("7Li6n) at a beam energy of 59 MeV. The excitation scheme of this nucleus has been extended by more than 110 new states, including extensions of all previously established rotational bands. The band crossing region of the h_9_/_2 negative-parity yrast band has been revised and new intrinsic high-K states have been identified. In particular, a 29/2"- isomeric state [T_1_/_2=1.8(5)#mu#s] at an excitation energy of 2487 keV has been observed for the first time, and on top of it, a rich level scheme reaching up to spin (59/2"-) and excitation energies around 7 MeV has been established.

Energy Technology Data Exchange (ETDEWEB)

This presentation outlined the energy policy in the United States and its impact on frontier development in Alaska, deepwater offshore fields and in the western oil shale resources. The energy strategy focuses on technologies that increase domestic production from existing resources as well as technologies that create new sources of energy. In addition to emphasizing the cooperation between Canada and the United States in ensuring energy supply security and stability, this paper discussed the importance of overall bilateral trade between the 2 countries. It was noted that Canada is the United State's most secure and reliable energy partner and is the number 1 supplier of imported oil, natural gas, electricity and uranium. The Bush administration's energy policy is based on the mandate to supply stable, reliable, secure, affordable and ...

Energy Technology Data Exchange (ETDEWEB)

Energy is a critical factor which determines the progress of rural development. Energy is therefore an area of concern. The quality, availability and cost of conventional energies, plus the associated environmental effects are a growing problem - not only for the health infrastructure but also for agriculture and domestic life. This is true not only in developing countries where the fast growing industries and urban populations demand a soaring proportion of available energy at the expense of the rural communities, but also in the poorest countries with weak energy infrastructure. Renewable energies, much studied in the last 20 years, can meet the needs of rural health and education services and communities by providing high quality, low cost, non-polluting energy. Solar energy, in particular, has ...

Energy Technology Data Exchange (ETDEWEB)

Renewable energy sources have been attracting the attention of a sensitized public since general pollution abatement measures have been taken, since efforts have been going into the protection of the earth atmosphere, the preservation of the vital ozone layer, and the conservation of fossil energy sources, and since nuclear power risks have been recognized and discussed. In addition to wind power and solar energy solid biomass, e.g. wood, wood wastes, vegetable residues and plants cultivated for the purpose of energy production, is among the topical alternatives. Agriculture and silviculture are important end-users of potential decentralized energy supplies and are cut out for supplying biomass for energy utilization. Additional income sources will open up for farmers. Based on these facts this KTBL working paper describes the biomass ...

Energy Technology Data Exchange (ETDEWEB)

At the 1996 Conference in North Carolina, The Green Institute began to share its story. Their presentation this year will cover where they are in the design process and their plans for using solar and wind technologies in the development of an Eco-Industrial Park and Business Incubator. Located in a Federal Enterprise Community in Minneapolis, this project borrows sustainable and green building principles using the Rocky Mountain Institute and Solar Living Center as models. Using a change in the paradigm regarding how industry does business, The Green Institute is joining with developments across the country that are putting together Eco-Industrial Parks which use closed loop production systems to reduce waste and emissions generated from manufacturing processes. Using renewable energy, both solar and wind, presents challenges both in the integration of systems on this small site and the educational opportunities with a large potential audience ...

International Nuclear Information System (INIS)

Efficient, low-temperature conversion of infrared light into visible light (red, orange, green) is reported at single heterojunctions and undoped quantum wells of GaAs and ordered Al_xGa_1_-_xInP_2; an increase in photon energy of 700 meV is obtained. The signal originates from the high-band-gap layers and disappears only if the excitation energy is tuned below the GaAs band gap. The intensity of the up-converted photoluminescence (PL) is found to decrease significantly slower with increasing temperature than that of the regular PL and it remains observable up to 200 K. Interface-induced cold Auger processes along with the presence of trapped states for both electrons and holes in these ordered alloys account for this nonlinear mechanism. A colinear double-beam experiment confirms this. copyright 1996 The American Physical Society.

British Library Electronic Table of Contents (United Kingdom)

We investigate quantum mechanical electron transport along the long axis of the DNA molecule using an effective tight-binding model. The overall contour plot of transmission, the current-voltage characteristics, and the differential conductance are examined for the variation of backbone onsite energy, the energy-dependent hopping strength, and the contact coupling between the leads and the DNA molecule. It is shown that as backbone asymmetry increases, the merging and collapse of the two mini-bands take place and an extra resonance peak in the transmission appears. In addition, we present the modulation of voltage threshold in the current-voltage curves and a double-peak structure in the differential conductance due to the disappearance of the merged mini-band. Finally, in the Coulomb bloc...

International Nuclear Information System (INIS)

Saskatchewan boasts the greatest concentration of high-grade uranium of any place in the world. Properly managed, its current reserves of 238U can easily fuel the entire province for some 10,000 years (in comparison, the world's oil supplies may be gone in 100). It is likely that Saskatchewan, with all that uranium, can build an industry and renew Canada's nuclear dream. The authors believe in the value of nuclear energy, in general, and the value of uranium mining in Saskatchewan and other parts of the world, in particular. We also believe in the value of research, development, innovation and training in the nuclear industry and the uranium industry

International Nuclear Information System (INIS)

Even as the recession begins to subside, the energy sector is still likely to experience challenging conditions as we enter 2011. It should be remembered how very important a role energy plays in driving the global economy. Serving as a simple yet global and unified measure of economic recovery, it is oil's price range and the strength and sustainability of the recovery which will impact the ways in which all forms of energy are produced and consumed. The report aims for a closer insight into these predictions: What will happen with M and A (Mergers and Acquisitions) in the energy industry?; What are the prospects for renewables?; Will the water-energy nexus grow in importance?; How will technological leaps and bounds affect E and P (exploration and production) operations?; What about electric cars? This is the second year Deloitte's Global ...

Energy Technology Data Exchange (ETDEWEB)

This conference provided a forum for discussing advances in the application of engineering principles and practices dealing with biological systems for the production of food, bioproducts and energy. The discussions focused on engineering practices in agriculture, forestry, bioresources, biochemistry and biosystems. The sessions of the conference were entitled: renewable energy and biofuels; food and bioproducts; odour and greenhouse gases; soil and water; waste management and bioresiduals; animal welfare and production; grain storage; machinery systems; structures and biocomposites; and, agricultural production. The conference also featured a workshop on modeling material and energy flows through agro-ecosystems. In addition to 22 posters, the conference featured 100 presentations, of which 8 have been catalogued separately for inclusion in this database. refs., tabs., figs.

Energy Technology Data Exchange (ETDEWEB)

An evaluation of Enova's heating program is presented. The central point was to evaluate to which degree Enova's heating program had resulted in increased supply of renewable energy for heating purposes to the Norwegian energy system. Main results are presented in part 1, chapter 1 to 5, while the facts and analyses behind the evaluation are presented in part 2, chapter I to VII. The main conclusion is that the program seen as one has had triggering effect on the market. The program has thus provided results in the form of increased supply of heating energy. Because of the project limitations and the lack of systematically documented baselines in the procedures, there are insecurities connected to the exact data registered. This makes quantification of the results difficult (ml)

Energy Technology Data Exchange (ETDEWEB)

The Coal and Electric Data and Renewables Division; Office of Coal, Nuclear, Electric and Alternate Fuels, Energy Information Administration (EIA), Department of Energy prepares the EPM. This publication provides monthly statistics at the State, Census division, and U.S. levels for net generation, fossil fuel consumption and stocks, quantity and quality of fossil fuels, cost of fossil fuels, electricity sales, revenue, and average revenue per kilowatthour of electricity sold. Data on net generation, fuel consumption, fuel stocks, quantity and cost of fossil fuels are also displayed for the North American Electric Reliability Council (NERC) regions. The EIA publishes statistics in the EPM on net generation by energy source; consumption, stocks, quantity, quality, and cost of fossil fuels; and capability of new generating units by company and plant.

British Library Electronic Table of Contents (United Kingdom)

In this work, we propose a conceptual distributed control framework for electrical grid integrated with distributed renewable energy generation systems in order to enable the development of the so-called ''smart electrical grid''. First, we introduce the key elements and their interactions in the proposed control architecture and discuss the design of the distributed control systems which are able to coordinate their actions to account for optimization considerations on the system operation. Subsequently, we focus on a specific wind/solar energy generation system connected to a reverse osmosis water desalination system and the electrical grid and design two supervisory predictive controllers via model predictive control to operate the integrated system taking into account short-term and lo...

Energy Technology Data Exchange (ETDEWEB)

Working in partnership with industry, the US Department of Energy`s (DOE`s) Office of Industrial Technologies (OIT) is helping reduce industrial energy use, emissions, and waste while boosting productivity. Operating within the Office of Energy Efficiency and Renewable Energy (EE), OIT conducts research, development, demonstration, and technology transfer efforts that are producing substantial, measurable benefits to industry. This document summarizes some of the impacts of OIT`s programs through 1997. OIT tracks energy savings as well as other benefits associated with the successfully commercialized technologies resulting from OIT-supported research partnerships. Specifically, a chart shows current and cumulative energy savings as well as cumulative reductions of various air pollutants including particulates, volatile organic compounds ...

Energy Technology Data Exchange (ETDEWEB)

Energy storage can be a cost-effective component of hybrid remote power systems. Storage serves the special role of taking advantage of intermittent renewable power sources. Traditionally this role has been played by lead-acid batteries, which have high life-cycle costs and pose special disposal problems. Hydrogen or zinc-air storage technologies can reduce life-cycle costs and environmental impacts. Using projected data for advanced energy storage technologies, LLNL ran an optimization for a hypothetical Arctic community with a reasonable wind resource (average wind speed 8 m/s). These simulations showed the life-cycle annualized cost of the total energy system (electric plus space heating) might be reduced by nearly 40% simply by adding wind power to the diesel system. An additional 20 to 40% of the wind-diesel cost might be saved by adding hydrogen storage or zinc-air fuel cells to the system. ...

Energy Technology Data Exchange (ETDEWEB)

Policy strategies for the promotion of electricity from renewable energy sources differ significantly among the Member States of the European Union with respect to the amount of additional installed capacity as well as concerning the country-specific support costs. The present report aims to assess the effectiveness and the economic efficiency of the support policies in the EU based on both historical experiences and prospective model-based analysis. The main message of the investigation is that the most effective policy instruments tend to be cost-efficient at the same time. In particular, feed-in tariff systems were identified as a successful instrument for supporting renewable energies in terms of effectiveness and efficiency, whereas quota systems still have to prove themselves in practice. (orig.) [German] Bezueglich des Erfolges bei der Foerderung erneuerbarer Energietraeger im Stromsektor ...

International Nuclear Information System (INIS)

The electron-phonon coupling constant lambda has been calculated for vanadium. The electron energy bands and wave functions were obtained from a model augmented plane wave muffin-tin potential. The electron-phonon matrix elements were evaluated using the rigid-ion approximation and the measured phonon spectra. The results show that lambda is strongly affected by d-f scattering.

International Nuclear Information System (INIS)

By using a model dielectric matrix in electron self-energy evaluations the computational effort of a quasiparticle band-structure calculation for a semiconductor is greatly reduced. Applications to various systems with or without inversion symmetry, having narrow or wide band gaps, and semiconductor alloys demonstrate the reliability and accuracy of the method. Calculations have been performed for thirteen semiconducting or insulating materials: Si, LiCl, AlP, AlAs, AlSb, GaP, GaAs, GaSb, InP, InAs, InSb, and the Al_0_._5Ga_0_._5As and In_0_._5_3Ga_0_._4_7As alloys. Excellent agreement with experimental results is obtained for the quasiparticle energies for these materials. The only three exceptions, E(#GAMMA#_1_c) of AlP, E(L_1_c) of AlAs, and E(L_1_c) of AlSb are discussed and attributed to various experimental uncertainties. Several other quasiparticle-excitation-related properties are also examined ...

International Nuclear Information System (INIS)

The universal depression of the superconducting transition temperature T/sub c/ in disordered A-15 compounds is examined. Existing energy-band calculations are used to calculate the density of electron states, which is possibly enhanced by disorder in some cases such as Nb_3Ge. The dramatic drop in T/sub c/ in Nb_3Ge at a critical value of the resistivity is attributed to overdamping of acoustic plasmons which decreases the electron pairing interaction despite small changes in the density of states.

Energy Technology Data Exchange (ETDEWEB)

Renewable Energy Technologies (RETS) have over the years become an integral part of the energy supply chain in most developed countries. Recent projections show that 13.5% of the world's primary energy supply comes from renewable and this figure has an aggregated annual growth rate of 16%. Wind has the highest annual growth rate of 22% while the least annual growth rate of 2% is for hydropower. The main push for renewable like wind in the OECD countries are environmental concerns and the business aspect in power generation. The situation is however completely different in Africa, where the thrust for RETs is developmental based. Although the continent has abundant renewable energy resources like solar, biomass, wind and hydro potential, they have remained largely unexploited. Several efforts have been made to ...

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Back in 1985 it was the European Commission's intention to demonstrate on rather large scale the provision of clean and renewable energy with hydrogen as energy vector and fuel. The cheapest and technologically available form of renewable electricity, the primary energy for electrolytic hydrogen, is hydropower. Most of the hydroenergy sources are oversea's. The World's topologically and technically exploitable hydroenergy potential is estimated to be in the order of 20.10{sup 3} TWh/y, i.e. 0.0057% of the hydraulic cycle energy. Today's hydroelectricity generation is {approx}2500 TWh/y i.e. {approx}21% of the World's electricity generation. Quebec's installed hydroelectricity is 33.5 GW, its residual potential is 50 GW or 190 TWh/y and 285 TWh/y, respectively (load factor 0.65). The construction of hydropower ...

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The slurry-Zn/air battery system has received renewed R and D interest because it does not have the shape-change problems of batteries with Zn-plate electrodes and can sustain higher current densities and specific peak power than other metal-air battery systems. Additional advantages of the slurry-Zn/air battery include safety, low environmental impact, potential low cost, and separation of energy density from power density functions for design purposes. In this work we present results obtained at the individual cell level as a basis to estimate the performance of a secondary slurry-Zn/air battery system. The expected specific energy of such systems has been increased as a result of the use of capacity-extension additives, which has been one of the major thrusts of this work. 8 refs., 20 figs., 5 tabs.

British Library Electronic Table of Contents (United Kingdom)

In the last years, the growing demand for air conditioning has caused a significant increase in demand for primary energy resources. Solar-powered cooling is one of the technologies which allows to obtain, by using the renewable solar source, an important energy saving compared to traditional air conditioning plants. The paper describes different technical installations for solar cooling, their way of operation, advantages and limits. The objective of the present study has been to analyze the technical and economic feasibility of solar absorption cooling systems, designed for two different application fields: industrial refrigeration and air conditioning. The possibility to replace or integrate the existing plants is studied, by considering the refrigeration requirements of a company, whic...

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The Materials and Components Technology Division (MCT) provides a research and development capability for the design, fabrication, and testing of high-reliability materials, components, and instrumentation. Current divisional programs related to nuclear energy support the development of the Integral Fast Reactor (IFR): life extension and accident analyses for light water reactors (LWRs); fuels development for research and test reactors; fusion reactor first-wall and blanket technology; and safe shipment of hazardous materials. MCT Conservation and Renewables programs include major efforts in high-temperature superconductivity, tribology, nondestructive evaluation (NDE), and thermal sciences. Fossil Energy Programs in MCT include materials development, NDE technology, and Instrumentation design. The division also has a complementary instrumentation effort in support of Arms Control Technology. Individual abstracts have been ...

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This study reported on the performance of a passive solar radiant floor heating system designed for standard energy-saving farmhouses in northeast China. Weather data in the region was analyzed in terms of solar radiation, temperature, humidity and light levels. The heating characteristics of the building materials such as windows, doors, walls and roofs were also analyzed along with the indoor thermal environment of the farmhouse. The heating load was then calculated along with the size of the thermal storage element and the area of the collector element. The passive solar radiant floor heating system was designed for heating during the winter and cooling in summer. According to the results, the heating characteristics of the system have the potential to improve farming villages environment and the use of renewable energy.

Environmental Research Database

ObjectivesThe practical exploitation of tidal stream energy is limited by man's activities in coastal waters: navigation, fishing and~%~leisure pursuits. It is important therefore to make the best use of the sites, which are available. The main objective of the~%~Proposed study is to assess the limits imposed by waves on the performance of tidal stream rotors, and to investigate way:~%~in which these limits might be related by refinements in rotor design and the control of operating conditions. Secondary~ [continued...]DescriptionHorizontal aids wind turbines have been recognised as one of the most successful renewable energy saving devices. The use of the similar concept as a 'tidy stream rotor' in offshore environment appears to be even more compelling. However, the application of this concept will require the confirmation of various operational and environmental limitations due to complexities of offshore environment ...

International Nuclear Information System (INIS)

The band crossing in "1"3"2Ba has been investigated by using the interacting boson model. A broken neutron pair has been coupled to a collective boson core. The boson-fermion interaction hamiltonian contains terms which can transform a boson into a pair of quasiparticles and vice versa. The parameters were partly determined by fitting the collective states of "1"3"2","1"3"4Ba and the yrast states of "1"3"1Ba. The energy backbending has been satisfactorily reproduced. Good agreement of the electromagnetic moments has been reached. The structure of the wave functions has been discussed. (author)

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A mathematical model has been constructed to describe the creation and filling of thermoluminescence traps during irradiation. Processes considered include trap filling, recombinations both between free charges and between free and trapped charges and thermal de-trapping. Also a simple trap creation term, linear with dose, has been included. A computer program has been written in order to solve the system of differential equations describing the various charge carrier flows during irradiation. The model and the program are described and the results of the application of the model to some simple energy-level schemes are discussed. Thermal de-trapping and band-to-band recombinations can introduce a dose rate dependence into the accumulation of trapped charge, whilst trap creation leads to the supralinear growth of charge trapped at certain defects with increasing dose.

International Nuclear Information System (INIS)

Local-density-functional calculations of the energy bands, equilibrium lattice constant, bulk modulus, and cohesive energy have been performed using a newly developed self-consistent full-potential linearized augmented-plane-wave (LAPW) program. Scalar-relativistic effects are included for the band states, and the core-level states are treated fully relativistically in a central-field approximation. Excellent agreement is obtained with the experimental lattice constant and bulk modulus. Generally good agreement is obtained with the scalar-relativistic pseudopotential results of Bylander and Kleinman. In this context, the impact of various approximations used in including the core states is assessed, and these findings are related to the frozen-core and pseudopotential approximations, especially with regard to the treatment of the somewhat overlapping 5p semicore states and their effect on ground-state ...

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The effect of the electric field on an exciton confined in a pair of vertically coupled quantum dots is studied. We use a single-band approximation and a parabolic model potential. As a result of these idealizations, we obtain a numerically solvable model, which is used to describe the influence of the electron-hole interaction on the Stark effect for the lowest-energy photoluminescence lines. We show that for intermediate tunnel coupling between the dots this interaction leads to an anomalous Stark effect with an essential deviation of the recombination energy from the usual quadratic dependence on the electric field.

International Nuclear Information System (INIS)

The detailed energy-band structure of hexagonal-close-packed technetium, corresponding to the atomic configuration 4d"55s"2 of its seven outermost valence electrons, has been obtained throughout the Brillouin zone using the composite-wave variational version of the augmented-plane-wave (APW) method in conjunction with the X#alpha# (#alpha# = 0.702 99) exchange approximation for obtaining the potentials. From the band-structure data the electronic density of states (DOS) and the angular-momentum--decomposed DOS were calculated by the accurate Gilat-Raubenheimer method. These quantities were used to calculate the electron-phonon coupling constant and the transition temperature (T/sub c/) using the theories of Gaspari and Gyorffy and of McMillan. Also studied were the Fermi surface and the optical properties of Tc via the imaginary part of the interband dielectric constant for bound electrons, the latter being the first of such a study on Tc to ...

International Nuclear Information System (INIS)

First-principles self-consistent band-structure calculations of potassium titanyl arsenate, KTiOAsO_4 (KTA), have been made using the full potential linearized augmented plane wave (FP-LAPW) method. Total and partial densities of states of the constituent atoms of KTA have been derived. The results obtained show that the valence band of KTA is dominated by contributions of the O 2p-like states, while the Ti 3d-like states are the main contributors into the conduction band of the compound. Additionally, the FP-LAPW calculations have revealed that potassium atoms are highly ionized in KTA. In the present work, the X-ray emission spectroscopy (XES) and X-ray photoelectron spectroscopy (XPS) methods were also employed to investigate experimentally the electronic structure of potassium titanyl arsenate. For the mentioned compound, the XES K Ll, Ti L#alpha#, As K#beta#_2 and O K#alpha# bands reflecting the ...

International Nuclear Information System (INIS)

There is an increasing interest in using novel methods to generate electrical energy using wind and solar energy sources. Unfortunately, such energy sources are intermittent, and, therefore, conventional sources must still be available to meet demand during critical periods. In addition, renewable energy technologies are still expensive in general, although extensive research programs are being conducted to overcome this disadvantage. Hence, reliability, economic assessment and environmental impacts are three objectives to be satisfied simultaneously when designing either an autonomous or a grid-connected hybrid power generation system. The installation of any of these two systems should, undoubtedly, be preceded by an assessment of the available resources at the candidate site. In addition, many other factors are to be studied, including economics of transmission lines, site ...

International Nuclear Information System (INIS)

A life cycle assessment was performed to quantify the non-renewable (fossil) energy use and global warming potential (GWP) in electricity generation from a typical gas fired combined cycle power plant in Singapore. The cost of electricity generation was estimated using a life cycle cost analysis (LCCA) tool. The life cycle assessment (LCA) of a 367.5 MW gas fired combined cycle power plant operating in Singapore revealed that hidden processes consume about 8% additional energy in addition to the fuel embedded energy, and the hidden GWP is about 18%. The natural gas consumed during the operational phase accounted for 82% of the life cycle cost of electricity generation. An empirical relation between plant efficiency and life cycle energy use and GWP in addition to a scenario for electricity cost with varying gas prices and plant efficiency have been established.

Energy Technology Data Exchange (ETDEWEB)

Thermophotovoltaic energy conversion achieves direct conversion of thermal energy to electricity without the need for complex dynamic machinery operating in one of several possible thermodynamic cycles. This paper presents an analysis of a hybrid solar thermophotovoltaic (STPV) energy conversion system in which a receiver/photovoltaic (PV) array subsystem is powered by either a solar concentrator or a fossil fuel combustion source. The overall TPV system efficiency is calculated using an appropriate selective emitter and a spectrally tuned solar cell designed to achieve maximum conversion efficiency in the narrow band emitted by the selective emitter. Two limiting cases are examined to place upper and lower bounds on system performance. The estimates of system performance are based on actual experimental data from PV cells and selective emitters.

Energy Technology Data Exchange (ETDEWEB)

The near normal incidence reflectivity of the ferromagnets U/sub 3/P/sub 4/ and U/sub 3/As/sub 4/ and the isostructural but diamagnetic compounds Th/sub 3/P/sub 4/ and Th/sub 3/As/sub 4/ has been measured from 0.03 to 12 eV. Trithorium tetraphosphide and tetraarsenide are shown to be indirect gap semiconductors with gap energies of 0.43 and 0.39 eV, respectively. U/sub 3/P/sub 4/ and U/sub 3/As/sub 4/ display similar sets of p..-->..d transitions than the corresponding thorium compounds, however, they are shifted by 0.85 eV to lower photon energies. It is concluded that the uranium compounds are metals due to a merging of the valence p band into the 6d conduction band giving direct experimental evidence for a p-f mixing effect of the same size. Energy level schemes are derived.

International Nuclear Information System (INIS)

We have performed self-consistent (SC) band structure calculations for the A15 compounds V_3X and Nb_3X, X = Al, Ga, Si, Ge, and Sn, using the augmented-plane-wave (APW) method. Relativistic effects (except the spin-orbit interaction) have been included in each SC cycle, along with corrections to the usual muffin-tin approximation. The latter apply the APW wave functions outside of the muffin-tin spheres to compute the interstitial charge densities and potentials. The resulting interstitial potential has full cubic symmetry (no spherical averaging), although a spherically averaged muffin-tin form is retained inside the spheres. The final SC potentials were used to generate energies and wave functions on a cubic mesh of 35 k points in 1/48th of the Brillouin zone. These results were interpolated onto a finer mesh of 969 k points using a symmetrized Fourier method; the densities of states (DOS), N (E), were determined using tetrahedral ...

Energy Technology Data Exchange (ETDEWEB)

European research in green energy production from crops has resulted in the development of full scale bioreactors that use energy crops as feedstock. Switchgrass has been touted as one of the most promising crops for energy production among several perennial grass species grown under moderate to hot climates. However, few studies have been conducted in colder climate conditions. This study examined the mesophilic methane yield of switchgrass grown under the cooler growing conditions that exist in northeastern North America. In 2007, switchgrass was harvested in late July, August and September and conserved as silage. The regrowth of plots harvested in late July was also harvested in late September as a two-cut strategy. A 30 L small-scale laboratory digester was used to anaerobically digest the switchgrass silage samples. Specific methane yield decreased considerably with advancing plant development, but was similar between ...

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The Electric Power Monthly (EPM) presents monthly electricity statistics for a wide audience including Congress, Federal and State agencies, the electric utility industry, and the general public. The purpose of this publication is to provide energy decisionmakers with accurate and timely information that may be used in forming various perspectives on electric issues that lie ahead. The Coal and Electric Data and Renewables Division; Office of Coal, Nuclear, Electric and Alternate Fuels, Energy Information Administration (EIA), Department of Energy prepares the EPM. This publication provides monthly statistics at the State, Census division, and US levels for net generation, fossil fuel consumption and stocks, quantity and quality of fossil fuels, cost of fossil fuels, electricity sales, revenue, and average revenue per kilowatthour of electricity sold. Data on net generation, fuel consumption, fuel ...

Energy Technology Data Exchange (ETDEWEB)

The conversion of off-peak surplus electricity into peak electricity through an electrolyzer, hydrogen storage, and fuel cell energy storage system was discussed. Development efforts in high pressure alkaline electrolysis and Proton-Exchange Membrane (PEM) fuel cells have improved the near-term viability of these systems. Potential use of wind turbines and other renewable energy-based generation systems, through hydrogen-based energy storage, were discussed as a new supply of surplus electricity. An integrated set of nomographs were presented for providing quick estimates of peak electricity costs derived from an electrolyzer/hydrogen fuel cell system. The nomographs allowed first order cost comparisons of centralized versus distributed hydrogen energy systems considering trade-offs between production economies of scale and hydrogen storage and transport costs. Use of the nomographs ...

Energy Technology Data Exchange (ETDEWEB)

The zinc-air battery/fuel cell is an old technology invented one hundred years ago. However, there is renewed interest in this technology in response to the growing need for clean energy technology. The zinc-air battery/fuel cell is more attractive than similar technologies because its characteristics include high power density, safe operation and storage, and low cost. Zinc-air battery/fuel cells can be made in milliwatts to mega watts to accommodate different applications. The zinc-air battery/fuel cell has four major designs, namely primary, mechanically rechargeable, continuous feed and electrically rechargeable zinc-air battery/fuel cells. Among the different designs, the most common is the air cathode. There are 3 generations of catalysts used in the air cathodes. This paper discussed the different designs of the zinc-air battery/fuel cell, and more specifically, the air cathode structure and performance.

Energy Technology Data Exchange (ETDEWEB)

Climate change and limited primary energy resources require indigenous renewable electricity generation options to change the current coal-dominated power source matrix in China. The wind power is such a solution for the above challenges, and it still has large space for improvement in China. In this paper several critical factors related to Chinese wind power were studied in details, including the wind resources, the wind turbine industry and the policies from the Chinese government. Based on the study, the perspective of wind power in China was discussed. With outstanding advantages, the offshore wind power has a bright future in China, so its main characteristics are discussed. Based on the discussions, suggestions were given to improve the development of Chinese wind power, and the government's further measures are also recommended. (author)

Energy Technology Data Exchange (ETDEWEB)

The Engineering and Technology Validation Team at the National Renewable Energy Laboratory (NREL) conducts in-situ technical evaluations of polycrystalline thin-film photovoltaic (PV) modules and arrays. This paper focuses on the technical evaluation of Solar Cells, Inc., (SCI) cadmium telluride (CdTe) module and array performance by attempting to correlate individual module and array performance. This is done by examining the performance and stability of the modules and array over a period of more than one year. Temperature coefficients for module and array parameters (P{sub max}, V{sub oc}, V{sub max}, I{sub sc}, I{sub max}) are also calculated.

Energy Technology Data Exchange (ETDEWEB)

Electricity generation from wind turbines is now cost competitive for grid and off-grid applications in many developing regions, and close to competitive in others. Wind resources could generate thousands of megawatts of badly-needed power in Asia, North Africa, and Latin America. Barriers to penetrating power generation markets remain, however, including unequal access to investment capital, energy price and other market distortions, and often weak institutions for commercializing new technologies. Recognizing the potential economic and environmental benefits of wind power, bilateral and multilateral assistance organizations have for several years offered financial and technical assistance to promote its diffusion. Based on this experience and assistance for other renewable electric technologies, lessons and recommendations can be drawn regarding how assistance could more effectively overcome persistent market and policy barriers, especially ...

Energy Technology Data Exchange (ETDEWEB)

Midway Labs currently produces a 335x concentrator module that has reached as high as 19{percent} active area efficiency in production. The current production module uses the single crystal silicon back contact SunPower cell. The National Renewable Energy Lab has developed a multi junction cell using GalnP/GaAs technologies. The high efficiency ({gt}30{percent}) and high cell voltage offer an opportunity for Midway Labs to develop a tracking concentrator module that will provide 24 volts in the 140 to 160 watt range. This voltage and wattage range is applicable to a range of small scale water pumping applications that make up the bulk of water pumping solar panel sales. {copyright} {ital 1997 American Institute of Physics.}

Energy Technology Data Exchange (ETDEWEB)

The gas phase high resolution spectroscopic study of weakly bound clusters can provide the information necessary to develop an intermolecular potential energy surface. This surface can then be used to better understand condensed phases. In this work, a tunable far infrared laser spectrometer is used to study weakly bound dimers produced in the newly developed continuous planar supersonic jet expansion apparatus. The water dimer is an extensively studied hydrogen bonded dimer. It undergoes several tunneling motions which result in splittings and perturbations of the rovibrational energy levels. A review is presented of much of the experimental and theoretical work done on water dimer, including a description of the combined fit of all the high resolution spectroscopic results by Coudert and Hougen. Also included is a discussion of the measurement of the K = 1 lower {yields} K = 2 lower band performed using the tunable far ...

Energy Technology Data Exchange (ETDEWEB)

Due to the great development occurred in the world after the Second World War and the establishment of patterns of increasingly intense, the energy demand amounted to the point, putting at risk the non-renewable energy sources such as oil, coal minerals, among others, with growing interest in renewable energies, among which the biodiesel has been detached. In this sense, the present work had for objective to evaluate the fuel consumption of a tractor Valtra BM100 4x2 TDA, running with ethyl biodiesel from soybean filtered in seven mixture proportions mixed with the diesel, subject to two forces in the traction bar. The work was conducted in the Department of Rural Engineering of the Paulista State University (UNESP), Jaboticabal Campus, in an entirely randomized designed, in a factorial diagram 2 x 7, with three repetitions. The treatments were a combination for two forces in the ...

Energy Technology Data Exchange (ETDEWEB)

A 150 Watt thermophotovoltaic (TPV) power generator is being developed. The technical approach taken in the design focused on optimizing the integrated performance of the primary subsystems in order to yield high energy conversion efficiency and cost effectiveness. An important aspect of the approach is the use of a selective emitter radiating to a bandgap matched photovoltaic array to minimize thermal and optical recuperation requirements, as well as the non-recoverable heat losses. For the initial prototype system, fibrous ytterbia emitters radiating in a band centered at 980 nm are matched with high efficiency silicon photoconverters. The integrated system includes a dielectric stack filter for optical energy recovery and a ceramic recuperator for thermal energy recovery. The system has been operated with air preheat temperatures up to 1350K. The design of the system and development status are ...

Energy Technology Data Exchange (ETDEWEB)

New rare earth oxide emitters show greater efficiency than previous emitters. As a result, based on a simple model the efficiency of these emitters was calculated. Results indicate that the emission band of the selective emitter must be at relatively low energy (less than or equal to .52 eV) to obtain maximum efficiency at moderate emitter temperatures (less than or equal to 1500 K). Thus low bandgap energy PV materials are required to obtain an efficient thermophotovoltaic (TPV) system. Of the 4 specific rare earths (Nd, Ho, Er, Yb) studied Ho has the largest efficiency at moderate temperatures (72 percent at 1500 K). A comparison was made between a selective emitter TPV system and a TPV system that uses a thermal emitter plus a band pass filter to make the thermal emitter behave like a selective emitter. Results of the comparison indicate that only for very optimistic filter and thermal emitter ...

Energy Technology Data Exchange (ETDEWEB)

We used light confinement in optical microcavities to achieve a strong enhancement and a precise wavelength tunability of the electrical photoconductance of nanostructured porous silicon (PS). The devices consist of a periodic array of alternating PS layers, electrochemically etched to have high and low porosities - and therefore distinct dielectric functions. A central layer having a doubled thickness breaks up the symmetry of the one-dimensional photonic structure, producing a resonance in the photonic band gap that is clearly observed in the reflectance spectrum. The devices were transferred to a glass coated with a transparent SnO{sub 2} electrode, while an Al contact was evaporated on its back side. The electrical conductance was measured as a function of the photon energy. A strong enhancement of the conductance is obtained in a narrow (17nm FWHM) band peaking at the resonance. We present experimental results of the ...

International Nuclear Information System (INIS)

A quantitative transmission electron microscopy (TEM) study on the depth profile of extended defects, formed after Si implantation, has been carried out. Two different Si"+ implant conditions have been considered. TEM analysis for the highest energy/dose shows that #left brace#1 1 3#right brace# defects evolve into dislocation loops whilst the defect depth distribution remains unchanged as a function of annealing time. For the lowest energy/dose, #left brace#1 1 3#right brace# defects grow and dissolve while the defect band shrinks preferentially on the surface side. At the same time, extraction of boron transient enhanced diffusion (TED) as a function of depth shows a decrease of the supersaturation towards the surface, starting at the location of the defect band. The study clearly shows that in these systems the silicon surface is the principal sink for interstitials. The results provide a critical ...

Energy Technology Data Exchange (ETDEWEB)

This document contains the technical proceedings of the 19 national seminar on the rational use of energy and exposition of equipment and services, organized by the Asociacion de Tecnicos y Pofesionistas en Aplicacion Energetica (ATPAE) (Association of Technicians and Professionals on Energy Application) conducted in Mexico City on September 21-25, 1998. This seminar encompassed subjects such as: energy saving in the energy sector, energy efficiency in industrial processes and practical developments, practical cases of energy saving in industry, energy saving in buildings, transportation, non-renewable energy utilization and environmental impact and eco-energies. [Espanol] Este documento contiene la memoria tecnica del 19 seminario nacional sobre el uso racional de la energia y ...

Energy Technology Data Exchange (ETDEWEB)

RADSOLVER is a computer program which calculates the radiation energy transport in cavity type receivers having an arbitrary number of apertures through which collimated beams of solar radiation enter. In contrast to the common assumption of gray (or semi-gray) surfaces used in the modeling of radiation transport, RADSOLVER accounts for the wavelength-dependence of emission, absorption and reflection with a band model of the radiative properties. It is intended that this report serve both as an instruction manual for the use of the RADSOLVER code and a vehicle for presenting the underlying theory. Illustrative examples along with input and output are presented.

International Nuclear Information System (INIS)

Currentless plasma in Uragan-3M (U-3M) is produced and heated by absorption of RF power in the region of Alfven waves (AW). The process of plasma heating was explained in (2) as a result of Cherenkov absorption of energy of the fast (EM) and slow (kinetic Alfven) waves by electrons and turbulent ion heating due to excitation of short wave ion Bernstein waves (IBW). In this report we present results of studies of plasma density fluctuations showing existence of a narrow bands near the frequencies of ? ? n?ci (n=1,2,3).

Energy Technology Data Exchange (ETDEWEB)

Pumped storage plants participate in two structurally different markets: the market for scheduled energy (also known as spot market) and the reserve market. In order to achieve the best possible plant scheduling in terms of revenues the marketing of the available capacity from pumped storage plants needs to be optimised in both markets. Moreover, due to the abilities for providing reserve, pumped storage capacities within an existing power plant portfolio can lead to synergies for the whole portfolio. The optimised combined participation of a power plant in both spot and reserve market as well as the coherent portfolio effect are considered as particular challenges in energy economic assessments, e.g. in the light of investment decisions. Based on an extension project and in cooperation with RWTH Aachen University an optimised combined participation of a power plant in both markets was simulated for the first time, thereby applying an ...

Energy Technology Data Exchange (ETDEWEB)

ZnO thin films were electrodeposited in aqueous solution on gilded p-type Si wafer substrates. Thermal treatments were carried out on different films in Ar atmosphere at different temperatures, between 200 and 600 {sup 0}C. Surface morphology studies using scanning electron microscopy and atomic force microscopy show a smooth surface for an annealing temperature of 400 {sup 0}C with a roughness mean square value of about 15 nm and a precipitation of ZnO microcrystals on the deposit surface at 600 {sup 0}C. X-ray diffraction experiments reveal a decrease in the c-parameter value from 5.223 to 5.206 A after treatment at 600 {sup 0}C, due to the removal of hydrogen from the film. Raman spectroscopy analyses show an improvement in the crystal quality of the film and a decrease in the compressive stress inside the deposit. Photoluminescence observations reveal an important change in the UV emission band after annealing at 200 {sup 0}C. A visible region emission ...

International Nuclear Information System (INIS)

We report the results of a theoretical study of the electronic and structural properties of the hexagonal beryllium nitride, using first principle pseudopotential plane wave (PP-PW) as well as full potential linearized augmented plane wave (FP-LAPW) methods within density functional theory. In the case of PP-PW we generated the pseudopotential by the highly optimized Q_c-tuning method and used the local density approximation and generalized gradient approximation (GGA) for the exchange-correlation potential. We applied pressure on the unit cell by the Wentzcovitch and traditional methods. In the FP-LAPW approach only the GGA was used for the exchange-correlation potential. Our calculated values for structural properties, based on both approaches are in reasonable agreement with experimental and other theoretical (Hartree Fock) results. By applying the above two approaches and also the Tight Binding Linear Muffin Thin Orbital method, the ground state Kohn-Sham eigenvalues were ...

International Nuclear Information System (INIS)

The [402]5/2 bands in "1"7"7Ta which are ''identical'' to the neighboring even-even "1"7"6Hf groundstate band have been extended to higher angular momentum. These bands in the two nuclei are seen to diverge from each other in the region of the first i_1_3_/_2 neutron alignment. The lower observed crossing frequency for the [402]5/2 bands indicates a lower deformation for these bands compared to "1"7"6Hf. Extensions to the h_9_/_2 [541]1/2 yrast band are also reported. (orig.).

Energy Technology Data Exchange (ETDEWEB)

Chapter 2 describes the worldwide increase of primary energy consumption, which is expected in coming decades and results in possible solutions of a decentralised energy supply that is mainly based upon renewable energy carriers and the use of cogeneration systems. Chapter 3 shows the characteristics of decentralised system components that have been investigated in the frame of this research work as well as the resulting model library to depict the operational performance of the individual components and their mutual influence. A detailed dynamic simulation of a complete fuel cell system based on a steam reformer including the concept of local and superordinate control circuits is presented in chapter 4. Chapter 5 includes the integrated concepts for the intelligent and adaptable management of complex decentralised energy systems as well as a description of their implementation. ...

International Nuclear Information System (INIS)

GaAs1-xPx p-n junction structures were grown on the epi-ready n-type GaAs(100) substrate by solid source MBE system for different phosphor compositions. To obtain the lattice-match sample structure was applied graded growth procedure. The structural and optical properties of the sample structures with different P concentration were investigated by using X-ray diffraction (XRD), spectroscopic ellipsometry (SE). In addition, The range of lattice parameters in the graded epilayer and phosphorous composition were determined from the HRXRD rocking curve simulation. We analyse dielectric function spectra of disordered GaAs1-xPx junction structures measured using spectroscopic ellipsometry at room temperature in the 0.6-4.7 eV photon energy region. The critical energy points such as band gap energy and spin-orbit-split energy of these structures were determined using SE data. It is ...

Energy Technology Data Exchange (ETDEWEB)

The pathway to hydrogen generation entirely from renewable energy and material sources probably goes by a transitional period with the utilization of hybrid fossil/renewable integrated systems. Solar steam reforming of methane is set in this context, specifically suited for a country like Italy whose actual energy policy is mainly based on the imported NG, but also characterized by convenient solar radiation levels in the Southern Regions. A new solar SMR process is being developed by ENEA, using molten nitrates as solar heat carriers and storage medium at about 550 C. The potential of this process have been proved theoretically by process simulation studies. Engineering and experimental activities aimed to the development of a prototype apparatus are now in progress in ENEA's laboratories. It is remarkable that the developed technology (MS powered SMR) can find interesting impact in the in ...

UK PubMed Central (United Kingdom)

Self-renewal of spermatogonial stem cells (SSCs) is the foundation for maintenance of spermatogenesis throughout life in males and for continuation of a species. The molecular mechanism underlying stem...Full Text Available

International Nuclear Information System (INIS)

Discussions regarding the use of wood fuels for commercial energy production in the Netherlands began in the 1990's. The main reasons for using wood fuel are: the political demand for using renewable energy, the need to reduce CO_2 emissions, and the lack of markets for surplus timber. Only 10 % of the area of Holland is forested. Therefore, early thinning and cleaning are important management tools for improving growth and producing better quality timber. The energy potential from early thinning and plantation cleaning could be between 400 000 and 570 000 dry tons annually. The Netherlands has not experience in harvesting energy wood. However, through the International Energy Agency/Bioenergy Agreement, knowledge gained in other countries, especially Denmark, Sweden and Finland, is being transferred to Holland. In 1996, there have been made field tests with ...

Energy Technology Data Exchange (ETDEWEB)

This report documents the development and use of the Greenhouse Gases, Regulated Emissions, and Energy Use in Transportation (GREET) model. The model, developed in a spreadsheet format, estimates the full fuel- cycle emissions and energy use associated with various transportation fuels for light-duty vehicles. The model calculates fuel-cycle emissions of five criteria pollutants (volatile organic compounds, carbon monoxide, nitrogen oxides, sulfur oxides, and particulate matter measuring 10 microns or less) and three greenhouse gases (carbon dioxide, methane, and nitrous oxide). The model also calculates the total fuel-cycle energy consumption, fossil fuel consumption, and petroleum consumption using various transportation fuels. The GREET model includes 17 fuel cycles: petroleum to conventional gasoline, reformulated gasoline, clean diesel, liquefied petroleum gas, and electricity via residual oil; natural gas to ...

Energy Technology Data Exchange (ETDEWEB)

A large number of proven technical solutions exists for the use of renewable energies (RE). However, their dissemination is still too slow to meet the political goal of substituting 12 % of the primary energy demand in the European Union by the year 2010. Even renewable energy systems (RES) with economic potential are only partly exploited. There is a long literature concerning the barriers to RE use. In particular it has become clear that the availability of finance and the forms and conditions upon which it is lent have a major impact on RE deployment. An area of importance is the deficiency of appropriate ownership forms and properly adapted financing instruments in certain countries. Moreover, different regulations and institutional barriers in the European countries hinder the free flow of capital for RES within the European common market. On the other hand, solutions have been ...

Energy Technology Data Exchange (ETDEWEB)

We have measured some of the optical characteristics of a novel energy conversion medium, over a range of compositions in the system Yb[sub 2]O[sub 3][minus]Al[sub 2]O[sub 3], which we have fabricated by a proprietary process. These specimens have good resistance to thermal shock, are durable, and are mechanically and chemically stable. The integrated emission of light generated by these unoptimized specimens when heated with a propane-air flame and detected with a silicon photodetector ranged up to 1.88 watts/cm[sup 2]. The emission spectrum from these specimens when heated with a propane-air flame and detected with a germanium photodetector shows a narrow band in the vicinity of 1 micron.

International Nuclear Information System (INIS)

The electron-phonon spectral distribution function #alpha#"2(#omega#) F (#omega#) has been calculated for niobium. The electron energy bands and wave functions were obtained from a self-consistent augmented-plane-wave muffin-tin potential, and the electron-phonon matrix elements were evaluated using the so-called rigid-ion approximation. With this approximation it is found that #alpha#"2(#omega#) is constant over the whole energy spectrum. The electron-phonon mass enhancement has also been calculated for local regions of the Fermi surface and found to be anisotropic. The calculated local values of the enhancement do not agree with experimental values available for different orbits from de Haas--van Alphen measurements. The discrepancy seems to arise because the bare-rigid-ion matrix elements are relatively small between states with nearly pure l = 2 character.

Energy Technology Data Exchange (ETDEWEB)

The construction and the development of a UV free electron laser have been started under the cooperation of Nihon U, KEK, PNC, ETL and Tohaku U. The project requires a 100MeV S-band electron linear accelerator to expand the oscillation of FEL using fundamental mode to the UV region. The injection system consists of a thermionic RF-gun with a LaB cathode and an {alpha} magnet for magnetic bunching. We are studying to reduce the back-bombardment electrons to realize the macropulse length of 20{mu}sec. Electron beams, up to the energy of 100MeV, are injected into the optical oscillators. Changing the accelerating energy and/or undulator parameters, this system will cover the range from infrared to ultraviolet for the applications in various fields.

Energy Technology Data Exchange (ETDEWEB)

The N{sub 1s} XPS band of pyridine chemisorbed on Al-ZSM-5 zeolite was found to be properly deconvoluted into three component peaks. In a previous contribution these three components were assigned to pyridine chemisorbed on two kinds of Bronsted acid sites and one Lewis acid site. This analysis is extended here to Fe-ZSM-5 and B-ZSM-5. Isomorphous substitution of Fe for Si or Al in the zeolite framework leads to a slight decrease in the binding energy of the N{sub 1s} Lewis component. In the case of B substitution a decrease in the binding energy of all three N{sub 1s} components is observed.

Environmental Research Database

ObjectivesTo obtain a benchmarked unsteady aerodynamic code for the S809 aerofoil; including Dynamic Stall. ~%~~%~The code will be that of Leishman & Beddoes suitably configured for the aerofoil's use on wind tubines. ~%~~%~To involve the international community during the assessment phase after benchmarking.~%~~%~To compare the data collected with that from the NWTC experiment.~%~~%~To improve the predictive capability of extant horizontal axis wind turbine performance codes. ~%~~%~To be compliant with b [continued...]DescriptionIn December 2000 the National Renewable Energy Laboratory (USA) held an international seminar to consider the predictive capabilities of w ind-turbine codes using their recently measured data. This highlighted the need for a detailed consideration of the codes sub-system with proper benc hmarking (became part of an ...

Energy Technology Data Exchange (ETDEWEB)

A wider use of renewable energy sources is considered to be the solution to fossil fuel depletion and environmental pollution. This paper discusses various design considerations for line focussing technology to achieve high efficiency and the possibility of generating power in the megawatt range based on solar thermal technologies. The impacts on the environment of conventional thermal power plants is outlined and an estimate made of the cost of pollution abatement measures. A cost benefit analysis is made using a typical 200 megawatt solar thermal plant, 500 km from the load centre, compared with a 220 megawatt coal fired and a similar capacity gas fired power plant, as examples. The results indicated that the energy from the solar thermal power plant is almost twice as expensive compared to conventionally generated electricity. If, however, impacts on the environment and notional cost associated with are considered, ...

Environmental Research Database

Objectives~%~~%~The practical exploitation of tidal stream energy is limited by man's activities in coastal waters: navigation, fishing and~%~leisure pursuits. It is important therefore to make the best use of the sites, which are available. The main objective of the~%~Proposed study is to assess the limits imposed by waves on the performance of tidal stream rotors, and to investigate way:~%~in which these limits might be related by refinements in rotor design and the control of openiting conditions. S~%~ [continued...]DescriptionHorizontal aids wind turbines have been recognised as one of the most successful renewable energy saving devices. The use of the similar concept as a 'tidy~%~~%~stream rotor' in offshore environment appears to be even more compelling. However, the application of this concept will require the confirmation of various operational and environmental limitations due to ...

International Nuclear Information System (INIS)

Systematic ensemble photoluminescence studies have been performed on type-I InP-quantum dots in Al_0_._2_0Ga_0_._8_0InP barriers, emitting at approximately 1.85 eV at 5 K. The influence of different barrier configurations as well as the incorporation of additional tunnel barriers on the optical properties has been investigated. The confinement energy between the dot barrier and the surrounding barrier layers, which is the sum of the band discontinuities for the valence and the conduction bands, was chosen to be approximately 190 meV by using Al_0_._5_0Ga_0_._5_0InP. In combination with 2 nm thick AlInP tunnel barriers, the internal quantum efficiency of these barrier configurations can be increased by up to a factor of 20 at elevated temperatures with respect to quantum dots without such layers. (copyright 2009 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

Energy Technology Data Exchange (ETDEWEB)

The effect of molybdenum on the electronic structure of the passive films formed on ferritic (Fe-Cr and Fe-Cr-Mo) stainless steels is examined by capacitance and photoelectrochemical measurements. The capacitance study is supported by a mathematical analysis of the Schottky barrier developed at the semiconductor-electrolyte interface in the case of a semiconductor with multiple bulk electronic states in the bandgap. The numerical simulations, based on the more general Mott-Schottky relation proposed, are in good agreement with the experimental results. It can be concluded that the capacitance behavior of the passive films is related to the contributions of a shallow donor level very close to the conduction band and a deep donor level at about 0.4 eV below the conduction band. The addition of molybdenum decreases the donor density of the deep level. Photoeffects observed for subbandgap photon energies reveal that this deep ...

Science.gov (United States)

The primary concern of this work is to study the emission characteristics of a series of chiral nematic liquid crystal lasers doped with different laser dyes (DCM, pyrromethene 580, and pyrromethene 597) at varying concentrations by weight (0.5-2 wt %) when optically pumped at 532 nm. Long-wavelength photonic band-edge laser emission is characterized in terms of threshold energy and slope efficiency. At every dye concentration investigated, the pyrromethene 597-doped lasers exhibit the highest slope efficiency (ranging from 15% to 32%) and the DCM-doped lasers the lowest (ranging from 5% to 13%). Similarly, the threshold was found to be, in general, higher for the DCM-doped laser samples in comparison to the pyrromethene-doped laser samples. These results are then compared with the spectral properties, quantum efficiencies and, where possible, fluorescence lifetimes of the dyes dispersed in a common nematic host. In accordance with the low ...

International Nuclear Information System (INIS)

A study trip to a biomass gasification plant in Germany took place from 13-15 November 2000. The goal of the trip was to obtain information on German developments, experience, and possibilities in the field of biomass gasification. The participants were representatives of Dutch parties in the energy sector: waste sector, manufacturers, producers, policy makers and consultants. The most important feature was the visit to plants that were in operation. Due in particular to the new EEG (Emeuerbare-Energien-Gesetz/Renewable Energy) legislation, German policy makers have created an initial market for sustainable energy with a degree of success. The key feature is that EEG makes projects 'bankable' by guaranteeing a return delivery compensation. An EEG-type scheme designed to accelerate the development of sustainable energy could be an interesting instrument also for the Netherlands. The ...

Energy Technology Data Exchange (ETDEWEB)

Alter both oil crisis, of 1973 and 1979, a bad effect of the elevated costs and continuously increment of the oil prices was noted, for this reason, the interest for renewable energies sources widely available in developing countries was increased. All over the world, governments have formulated main objectives for energies savings and search for friendly technologies, taking into account the effects related with the environment. The imminent scarcity of fossil fuels has made humanity the rational use of primary energies, as a result of these; new plants with improved technology have been conceived taking into account energy savings and efficiency improvement. In this context, biomass gasification technologies are important, since they consist in techniques of parallel production of electricity and heat from just one fuel. This work consists in the development of a gasifier down ...