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‣ The FEA Project Independence report: an analytical review and evaluation

MIT Energy Laboratory Policy Study Group
Fonte: MIT Energy Lab Publicador: MIT Energy Lab
Tipo: Relatório Formato: 6572499 bytes; application/pdf
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Final report to Office of Energy Research and Development Policy, National Science Foundation, Contract NSF C-1030

‣ NEEMIS overview : New England Energy Management Information System

MIT Energy Lab
Fonte: MIT Energy Lab Publicador: MIT Energy Lab
Tipo: Trabalho em Andamento Formato: 296255 bytes; application/pdf
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Prepared in association with the Alfred P. Sloan School of Management

‣ Applied solar energy at the Shiraz Technical Institute

Meyer, James Wagner
Fonte: MIT Energy Lab Publicador: MIT Energy Lab
Tipo: Trabalho em Andamento Formato: 1316639 bytes; application/pdf
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Factors affecting the application of solar energy and the preliminary design of a solar system to supplement the service hot water system at the Shiraz Technical Institute are described. In addition to the solar energy demonstration, the educational benefits of selected solar projects and laboratory experiments are discussed. An effective, yet expandable, initial installation can be made at reasonably low cost because advantage is taken of architectural features of the buildings and the nature of the conventional service hot water heating system. Opportunities for the future are also briefly considered.

‣ International comparisons of the residential demand for energy

Pindyck, Robert S.
Fonte: MIT Energy Laboratory Publicador: MIT Energy Laboratory
Tipo: Trabalho em Andamento Formato: 5905632 bytes; application/pdf
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A revised and updated version of "International comparisons of the residential demand for energy: a preliminary analysis," Working paper #MIT-EL 76-023WP, by the same author.; Supported by the National Science Foundation under Grant #GSF SIA075-00379.

‣ Consumer choice of durables and energy demand

Hausman, Jerry A.
Fonte: MIT Energy Laboratory Publicador: MIT Energy Laboratory
Tipo: Trabalho em Andamento Formato: 1859385 bytes; application/pdf
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Research supported by the NSF, M.I.T. Energy Laboratory and EPRI.

‣ Waste heat management in the electric power industry : issues of energy conservation and station operation under environmental constraints

Adams, E. Eric; Harleman, Donald R. F.
Fonte: MIT Energy Laboratory Publicador: MIT Energy Laboratory
Tipo: Relatório Formato: 3133327 bytes; application/pdf
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Over the past three years, the Energy Laboratory, in cooperation with the R.M. Parsons Laboratory for Water Resources and Hydrodynamics at M.I.T. has been under contract with DOE/ECT to study various water and waste heat management issues associated with the choice of cooling systems for large steam-electric power plants. The purpose of this report is to summarize the major findings to-date of this study. In addition, an introduction or background section proceeds the summary so that the results can be better integrated into the larger picture of water and waste heat management.; Over the past three years, the Energy Laboratory, in cooperation with the R.M. Parsons Laboratory for Water Resources and Hydrodynamics at M.I.T. has been under contract with DOE/ECT to study various water and waste heat management issues associated with the choice of cooling systems for large steam-electric power plants. The purpose of this report is to summarize the major findings to-date of this study. In addition, an introduction or background section proceeds the summary so that the results can be better integrated into the larger picture of water and waste heat management.

‣ Transmission pricing of distributed multilateral energy transactions to ensure system security and guide economic dispatch

Ilic, Marija D.; Hsieh, Eric; Ramanan, Prasad
Fonte: MIT Center for Energy and Environmental Policy Research Publicador: MIT Center for Energy and Environmental Policy Research
Tipo: Trabalho em Andamento Formato: 7 p
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In this paper we provide a simulations-based demonstration of a hybrid electricity market that combines the distributed competitive advantages of decentralized markets with the system security guarantees of centralized markets. In this market, the transmission service provider (TSP) guides an electricity market towards the optimal power flow (OPF) solution, even when maximizing its own revenue. End users negotiate with each other to determine an energy price and then submit separate bids for transmission to the TSP. The TSP returns with prices for transmission, allowing end users to respond. In simulations, this hybrid-decentralized market approaches the near-optimal results of fully coordinated and constrained markets. Additionally, this market exhibits properties that remove incentives for the TSP to withhold capacity. This hybrid market leads a market towards the optimum while allowing the TSP and the end users to act out of self-interest. Index Terms₇Electricity markets, transmission, optimum power flow.; Supported by the MIT Center for Energy and Environmental Policy Research.

‣ What should the government do to encourage technical change in the energy sector?

Deutch, John M.
Fonte: MIT Center for Energy and Environmental Policy Research Publicador: MIT Center for Energy and Environmental Policy Research
Tipo: Trabalho em Andamento Formato: 16 p
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Government support of innovation - both technology creation and technology demonstration - is desirable to encourage private investors to adopt new technology. In this paper, I review the government role in encouraging technology innovation and the success of the Department of Energy (DOE) and its predecessor agencies in advancing technology in the energy sector. The DOE has had better success in the first stage of innovation (sponsoring R&D to create new technology options) than in the second stage (demonstrating technologies with the objective of encouraging adoption by the private sector). I argue that the DOE does not have the expertise, policy instruments, or contracting flexibility to manage successfully technology demonstration, and that consideration should be given to establishing a new mechanism for this purpose. The ill-fated 1980 Synthetic Fuels Corporation offers an interesting model for such a mechanism.

‣ The long-run evolution of energy prices

Pindyck, Robert S.
Fonte: MIT Center for Energy and Environmental Policy Research Publicador: MIT Center for Energy and Environmental Policy Research
Tipo: Trabalho em Andamento Formato: 35 p
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I examine the long-run behavior of oil, coal, and natural gas prices, using up to 127 years of data, and address the following questions: What does over a century of data tell us about the stochastic dynamics of price evolution, and how it should be modeled? Can models of reversion to stochastically fluctuating trend lines help us forecast prices over horizons of 20 years or more? And what do the answers to these questions tell us about investment decisions that are dependent on prices and their stochastic evolution?; Supported by the MIT Center for Energy and Environmental Policy Research.

‣ Toward Sustainable and Energy Efficient Urban Transport

Energy Sector Management Assistance Program
Fonte: World Bank, Washington, DC Publicador: World Bank, Washington, DC
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Many cities of developing countries are experiencing rapid growth of motorized transportation. This is leading to severe congestion, which, in turn, is reducing productivity. Road accidents have been increasing. Transport emissions have become a major contributor to severe air pollution and greenhouse gas emissions. The main cause of these problems has been the increasing preference for personal motor vehicles for commuting to work and getting around the city. In many countries, urban development practices have worked in favor of such preference, leading to urban sprawl. Thus, remedial measures have to focus on reversing the preference for such modes of travel, shifting to public transport, cycling, or walking, and building and retrofitting cities to minimize the need for private automobiles. The objective of this guidance note is to present a systematic, practical, and comprehensive approach to dealing with the problems of urban transport. It outlines a framework of possible interventions and demonstrates how such interventions relate to the overall objectives of improving mobility and energy efficiency as well as reducing air pollution and road accidents. Thereafter...

‣ Development, use and control of nuclear energy for the common defense and security and for peaceful purposes

United States -- Congress. -- Joint Committee on Atomic Energy
Fonte: Supt. of Docs., U.S. Govt. Print. Off.; Supt. of Docs., U.S. Govt. Print. Off. ( Washington ) Publicador: Supt. of Docs., U.S. Govt. Print. Off.; Supt. of Docs., U.S. Govt. Print. Off. ( Washington )
Tipo: Artigo de Revista Científica Formato: v. : 24 cm.
Publicado em // Português
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(Dates or Sequential Designation) 1st- 1975-; (Numbering Peculiarities) Report covers fiscal year 1976.; CIS Microfiche Accession Numbers: CIS 75 J803-13, CIS 76 J802-4; Reuse of record except for individual research requires license from LexisNexis Academic & Library Solutions.; Reuse of record except for individual research requires license from Congressional Information Service, Inc.; "Second annual report to the United States Congress by the Joint Committee on Atomic Energy pursuant to section 202(b) of the Atomic energy act, as amended."; At head of title: 94th Congress, 2d session. Joint committee print.

‣ Energy resources management in three distinct time horizons considering a large variation in wind power

Silva, Marco; Morais, Hugo; Sousa, Tiago; Vale, Zita
Fonte: The European Wind Energy Association - EWEA Publicador: The European Wind Energy Association - EWEA
Tipo: Conferência ou Objeto de Conferência
Publicado em /02/2013 Português
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The intensive use of distributed generation based on renewable resources increases the complexity of power systems management, particularly the short-term scheduling. Demand response, storage units and electric and plug-in hybrid vehicles also pose new challenges to the short-term scheduling. However, these distributed energy resources can contribute significantly to turn the shortterm scheduling more efficient and effective improving the power system reliability. This paper proposes a short-term scheduling methodology based on two distinct time horizons: hour-ahead scheduling, and real-time scheduling considering the point of view of one aggregator agent. In each scheduling process, it is necessary to update the generation and consumption operation, and the storage and electric vehicles status. Besides the new operation condition, more accurate forecast values of wind generation and consumption are available, for the resulting of short-term and very short-term methods. In this paper, the aggregator has the main goal of maximizing his profits while, fulfilling the established contracts with the aggregated and external players.

‣ Performance assessment of a wind energy conversion system using a hierarchical controller structure

Melicio, Rui
Fonte: Energy Conversion and Management-Elsevier Publicador: Energy Conversion and Management-Elsevier
Tipo: Artigo de Revista Científica
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This paper deals with a hierarchical structure composed by an event-based supervisor in a higher level and two distinct proportional integral (PI) controllers in a lower level. The controllers are applied to a variable speed wind energy conversion system with doubly-fed induction generator, namely, the fuzzy PI control and the fractional-order PI control. The event-based supervisor analyses the operation state of the wind energy conversion system among four possible operational states: park, start-up, generating or brake and sends the operation state to the controllers in the lower level. In start-up state, the controllers only act on electric torque while pitch angle is equal to zero. In generating state, the controllers must act on the pitch angle of the blades in order to maintain the electric power around the nominal value, thus ensuring that the safety conditions required for integration in the electric grid are met. Comparisons between fuzzy PI and fractional-order PI pitch controllers applied to a wind turbine benchmark model are given and simulation results by Matlab/Simulink are shown. From the results regarding the closed loop point of view, fuzzy PI controller allows a smoother response at the expense of larger number of variations of the pitch angle...

‣ Generation, characteristics and energy potential of solid municipal waste in Nigeria

Amber,Ityona; Kulla,Daniel M; Gukop,Nicholas
Fonte: Journal of Energy in Southern Africa Publicador: Journal of Energy in Southern Africa
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2012 Português
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The generation, characteristics and energy potential of municipal solid waste for power generation in Nigeria is presented in this paper. Nigeria generates 0.44-0.66 kg/capita/day of MSW with a waste density of 200-400 kg/m³ leading to large volumes of poorly managed waste. The direct burning of these wastes as a waste management option in the open air at elevated temperatures liberates heat energy, inert gases and ash which can be conveniently used for power generation and other applications. The net energy yield depends upon the density and composition of the waste; relative percentage of moisture and inert materials, size and shape of the constituents and design of the combustion system. MSW samples used in this study were obtained randomly from different dump sites in selected state capitals, at least one from each of the six geopolitical zones in Nigeria based on the spot sampling method of Corbit. An average calorific value of 17.23 MJ/kg with variable high water content of 20-49% was determined for MSW using a bomb calorimeter and on the basis of an incineration plant of capacity 1500 ton of MSW/day, 700kW/day of power can be generated.

‣ Energy consumption and real GDP: Panel co-integration and causality tests for sub-Saharan African countries

Fowowe,Babajide
Fonte: Journal of Energy in Southern Africa Publicador: Journal of Energy in Southern Africa
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2012 Português
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This paper investigates the causal relationship between energy consumption and real GDP in 14 Sub-Saharan African countries over the period 1971-2004. The results of panel co-integration tests showed that energy consumption and real GDP do not have a stable long-run equilibrium relationship. We find that for all members of the panel, there is homogenous causality from energy consumption to real GDP and vice versa. This bi-directional causality supports the feedback hypothesis.

‣ Energy cost versus production as a performance benchmark for analysis of companies

Taghizadeh,Houshang; Pourrabbi,Mir Vahid
Fonte: Journal of Energy in Southern Africa Publicador: Journal of Energy in Southern Africa
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2013 Português
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In this paper, the efficiency of automobile and auto-parts producing companies is evaluated, using data envelopment analysis. The data envelopment analysis (DEA) is based on the linear programming model. This model needs a series of information by which the effectiveness and ineffectiveness of decision-making units are determined. In the present research, the inputs and outputs of the DEA model are determined by using the basic criteria, and the energy efficiency of automobile and auto-parts producing companies is specified. For this purpose, to evaluate the energy efficiency of the automotive industry and auto parts producing companies, deep2 software has been used. Finally, based on the results of the study, the efficient and inefficient companies have been identified and classified.

‣ Using participatory GIS to examine social perception towards proposed wind energy landscapes

Lombard,Andrea
Fonte: Journal of Energy in Southern Africa Publicador: Journal of Energy in Southern Africa
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/05/2015 Português
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Thirteen onshore wind farm projects, totalling approximately 700 wind turbines, are proposed for the West Coast Region (WCR) of the Western Cape Province in South Africa. Wind energy exploitation possesses the ability to transform what can be classified as natural landscapes into landscapes of power, making the type of landscape on which wind turbines are deployed a prominent factor in its social acceptance or rejection. This paper examines the landscape aesthetics and land use interference of proposed wind farms in the WCR of South Africa through determining if social acceptance or rejection of proposed wind farms is dependent on the residents and visitors scenic and land use valuation of the natural landscape. The results indicate that the visual intrusion of wind turbines is the impact that respondents are least concerned with contrasting with the findings of international literature and further reasons for this anomaly are interrogated against the background of South Africa's dire electricity needs. The paper concludes that visual impact assessments alone are not sufficient for evaluating landscapes and this paper recommends that participatory geographic information systems (PGIS) be used in addition to existing wind energy landscape assessments.

‣ Electrical and thermal analysis of an asynchronous machine for application in wind energy generation

Okoro,O I; Chikuni,E
Fonte: Journal of Energy in Southern Africa Publicador: Journal of Energy in Southern Africa
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2008 Português
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The electromagnetic (electrical) and mechanical design of an Asynchronous machine for application in wind energy generation depends on the knowledge of heat transfer within the various parts of the machine. Unfortunately, the analysis of thermal effect in Asynchronous motors is usually more complex, more non-linear and more difficult than the electromagnetic behaviour. This paper therefore, sets out to investigate the effect of coupling the electrical model with the thermal model of the machine. The results of the analysis show that the proposed coupled model is capable of predicting the stator phase currents, rotor bar temperature, stator windings temperature, heat losses, rotor speed and electromagnetic torque of the test machine under dynamic conditions and at rated load operation. The analysis finds application in wind energy generation especially when modified and applied to synchronous generators. By so doing, the prediction of critical temperatures of machine parts can be achieved prior to machine operation.

‣ Possible developments in energy conversion using liquid metal magnetohydrodynamics

Kapooria,Raj Kumar
Fonte: Journal of Energy in Southern Africa Publicador: Journal of Energy in Southern Africa
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2009 Português
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Liquid metal magneto-hydrodynamic-energy-con-version (LMMHDEC) systems have been a matter of great interest and research & development since 1960. The various states of design and development of such systems go through a step-by-step progress with time. This paper highlights the phenomenon of direct thermal energy conversion systems using liquid metal as an electrodynamics fluid and gas/vapour as a thermodynamic fluid. An analysis of the technological drawbacks responsible for low efficiency of these LMMHDEC systems along with possible R & D solutions have been discussed in this technical research paper. The separation of electrodynamics fluid from thermodynamic fluid at various stages of MHD conversion remained an efficiency challenge of the various types of systems. To meet this challenge, a Dual-cycle MHD system has been designed in this paper. Both the fluids viz. thermodynamic and electrodynamics go through a phase change in this cycle. The thermal efficiency is optimized when one fluid goes into a phase change during a cycle and another fluid does not experience any phase change. The information covered in this paper enables an overview of concepts and the background to choose a cycle for a given temperature range.

‣ A review of electrical energy management techniques: Supply and consumer side (industries)

Mohamed,Afua; Khan,Mohamed Tariq
Fonte: Journal of Energy in Southern Africa Publicador: Journal of Energy in Southern Africa
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2009 Português
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A review of electrical energy management techniques on the supply side and demand side is presented. The paper suggests that direct load control, interruptible load control, and time of use (TOU) are the main load management techniques used on the supply side (SS). The supply side authorities normally design these techniques and implement them on demand side consumers. Load management (LM) initiated on the demand side leads to valley filling and peak clipping. Power factor correction (PFC) techniques have also been analysed and presented. It has been observed that many power utilities, especially in developing countries, have neither developed nor implemented DSM for their electrical energy management. This paper proposes that the existing PFC techniques should be re-evaluated especially when loads are nonlinear. It also recommends automatic demand control methods to be used on the demand side in order to acquire optimal energy consumption. This would lead to improved reliability of the supply side and thereby reducing environmental degradation.