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Dimensionamento de usinas hidroelétricas através de técnicas de otimização evolutiva ; Sizing hydropower plants via evolutionary optimization techniques

Silva Filho, Donato da
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 18/12/2003 PT
Relevância na Pesquisa
46.12%
As metodologias normalmente utilizadas para otimizar as dimensões de uma usina hidroelétrica, incluindo os métodos empregados pelo Setor Elétrico Brasileiro, baseiam-se em análises do tipo custo/benefício. Os custos provêm de gastos diretos com a construção da usina e os benefícios correspondem a receitas proporcionadas pela venda de energia. Para avaliar os benefícios, são realizadas simulações da operação da usina e a energia produzida é valorizada economicamente. Esta necessidade das simulações da operação faz com que o problema de dimensionamento não possua uma função analítica explícita para determinar os benefícios energéticos, o que dificulta a implementação de métodos tradicionais de otimização. O objetivo deste trabalho é justamente desenvolver e implementar uma metodologia de dimensionamento que permita que o processo de busca pelas dimensões ótimas seja automático. Para tanto, acoplam-se um modelo de otimização evolutiva e um modelo de simulação da operação de sistemas hidroelétricos. Adicionalmente, o modelo proposto também deve ser flexível, permitindo que as regras de operação do sistema hidroelétrico, o conjunto de vazões afluentes, a forma de valorização da energia gerada e uma série de outros fatores sejam tratados como parâmetros do modelo. Os resultados encontrados indicam que...

Economically and ecologically sustainable adoption of stationary fuel cells in the USA

Bhaumick, Benjamin, 1967-
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 93 leaves; 6179113 bytes; 6187954 bytes; application/pdf; application/pdf
ENG
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55.62%
Energy in various forms is essential to all human activity, be it leisure or business. Currently employed stationary energy generation technology is marked by relatively high emissions of pathogenic chemicals such as carbon dioxide, sulfur oxide and other criteria pollutants. These chemicals are proven to adversely affect human health and are suspected of influencing the global climate. Consequently, there is a high potential for damages in some parts of earth but also benefits in others, particularly to agricultural yields and weather related catastrophes. Last not least, current energy conversion is largely based on fossil fuels such as coal, gas and oil. On timescales relevant to humans, these sources are physically exhaustible and beyond that economically not sustainable. This thesis will provide details of renewable and therefore sustainable energy concepts as they support the emergence of hydrogen based stationary energy conversion using fuel cells. Given this premise, several sources of naturally available and long-term sustainable energy supply are identified, quantified and discussed with respect to their economical utilization. Wind energy, foremost, but also solar energy, hydropower and others are identified as viable options for generating hydrogen. Fuel cells provide the link between intermittent and randomly located renewable energy sources and demand properties. Given infrastructure availability will identify natural gas as the immediate but transitional hydrogen source prior to renewable energy being commercially viable at large scales. Since technical obstacles to fuel cell adoption can be overcome...

Enhancing Development Benefits to Local Communities from Hydropower Projects : A Literature Review

World Bank
Fonte: Washington, DC Publicador: Washington, DC
EN_US
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66.31%
The World Bank began a three-year pilot initiative to develop a framework for enhancing development benefits to local communities in hydropower projects. There has been a wide array of approaches in the past two decades that all have in common the objective of designing and implementing means and mechanisms to ensure local communities a more equitable share of project benefits. The World Bank intends to design and test a framework of enhancing development benefits that can be applied to hydropower projects and that can be tailored, at the same time, to the particular circumstances and characteristics of individual projects. This initiative is based on the hypothesis that hydropower projects planned in environmentally and socially sustainable manner can provide a large range of development benefits to local communities. Structure of this report: chapter one provides an introductory background to the literature review briefly explaining the current context of hydropower projects, the scope of the assignment and the structure of this report. Chapter two offers the core of the intellectual discussion by describing the approach and methodology utilized for the literature review...

Enhancing Development Benefits to Local Communities in Hydropower Projects : Technical Workshop

World Bank
Fonte: Washington, DC Publicador: Washington, DC
EN_US
Relevância na Pesquisa
66.31%
The technical workshop on enhancing development benefits to local communities in hydropower projects was held in Washington, D.C., on June 26, 2008. It was hosted by the Social Development Department (SDV) and Water Anchor (ETWWA) of the World Bank. The workshop aimed to provide a platform for a discussion of past and current practices, as well as how to construct development benefits mechanisms within the specific context of hydropower projects. It also provided a forum for sharing knowledge as to how development benefits mechanisms may be applied to Bank-financed projects. The workshop had five sessions and brought together more than 60 experts from different sectors in different regions of the World Bank. Sixteen speakers gave presentations. The workshop had discussions on enhancing development benefits to local communities in hydropower projects and also covered issues pertaining to the broader range of benefit-sharing, including World Bank engagement in hydropower projects, legacy of hydropower, notion evolution...

Financing of Private Hydropower Projects

Head, Chris
Fonte: Washington, DC: World Bank Publicador: Washington, DC: World Bank
EN_US
Relevância na Pesquisa
66.05%
This study provides an overview of the issues and challenges related to the private financing of hydropower projects in developing countries. From the very limited pool of projects that have already reached or are nearing financial closure, ten have been chosen for the study from five countries with the most active in promoting private hydro development. Collectively the case study projects provide a reasonable cross-section of private hydro schemes that have been or are being developed. The financing of greenfield private infrastructure on a limited-recourse basis in developing countries faces certain common issues irrespective of the type of project. However, hydropower faces additional difficulties caused by the site-specific nature of projects, high construction risk and long construction periods, their capital-intensive nature with a high proportion of local costs, unpredictable output subject to river flows and broader water management constraints, complex concession process to achieve transparency in the award and pricing of output...

Rehabilitation of Hydropower : An Introduction to Economic and Technical Issues

Goldberg, Joseph; Espeseth Lier, Oeyvind
Fonte: World Bank, Washington, DC Publicador: World Bank, Washington, DC
EN_US
Relevância na Pesquisa
66.16%
Section one provides a concise summary of the results of the study and includes an overview of the conclusions as well as lessons learned based on the assessment of the case studies. Section two gives the context for the study including the definition of a set of hydroelectric project development options as background to related discussions of rehabilitation later in the report. Section three provides an overview of the contents of this report. Section four discusses the development and application of an assessment tool to facilitate the rapid assessment of regional hydropower inventories. This assessment tool has been applied to a data base and inventory of generating station information in the African and Central American regions to identify possible candidates for rehabilitation. The characteristics of the two inventories are outlined in the section and details of the approach and the results of the application of the tool to the two regions are given in annex A. Section five presents a screening-level economic assessment model which quantifies potential costs and benefits associated with hydropower rehabilitation...

Designing Strategies and Instruments to Address Power Projects Stress Situations

Meyerman, Gerald; Covindassamy, Ananda M.
Fonte: World Bank, Washington, DC Publicador: World Bank, Washington, DC
EN_US
Relevância na Pesquisa
46.1%
It is an internationally recognized reality that continued and increased investment in the power sector by private firms is essential to providing affordable and reliable energy to an increasing portion of the world population. However, investing in power projects in the developing regions of the world exposes nations, governments, consumers, and investors to unusually high levels of risk. This study will have succeeded if it encourages parties, on all sides, to recognize problems as early as possible and concentrate on identifying possible solutions, and then implementing them. This study marks the interest of investors and lenders in finding procedures and instruments to facilitate the resolution of disputes arising from stress situations. To begin with we will summarize the predominant causes, characteristics, and consequences of project stress in the energy sector of emerging markets. The author will seek to describe and understand the incidence of various patterns of characteristics and consequences of project stress that emerge as power projects are broken down by type industry stage and region. Then the author will discuss how to prevent the emergence of stress situations in power projects as well as the instruments and strategies available for the resolution of power project stress.

Peru Opportunities and Challenges of Small Hydropower Development

Meier, Peter; Zolezzi, Eduardo H.; Bogach, Susan V.; Muir, Terence; Bazex, Karen
Fonte: World Bank, Washington, DC Publicador: World Bank, Washington, DC
EN_US
Relevância na Pesquisa
56.1%
Peru is favored by a stable and growing economy and the availability of indigenous sources of energy for electricity generation, including hydro and natural gas. The Peruvian electricity sector is among the few in Latin America and Caribbean (LAC) that has not confronted a crisis in recent years. The power sector in Peru was reformed and restructured between 1991 and 1993, followed by a privatization and concession process. A modern legal and regulatory framework was established in the electricity concessions law of 1992-93. This report contains the following chapters: (1) introduction; (2) resource potential and technical capacity for development of small hydropower in Peru; (3) economic and financial viability of small hydro development in Peru; (4) institutional and regulatory environment; (5) identification of barriers to small hydropower development and mitigation measures; (6) international experience with small hydropower development; and finally (7) conclusions and recommendations.

A Guide for Local Benefit Sharing in Hydropower Projects

Wang, Chaogang
Fonte: World Bank, Washington, DC Publicador: World Bank, Washington, DC
EN_US
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56.26%
Local benefit sharing in hydropower projects can be defined as the systematic efforts by project proponents to sustainably benefit local communities affected by hydropower investments. Benefit sharing is a promising approach for implementing hydropower projects sustainably, and is emerging as a supplement to the requirements of compensation and mitigation. Benefit sharing can provide equitable development, sustainability, and smooth project implementation for hydropower development. For benefit sharing mechanisms to work, the key enabling conditions are government policies, the legal and regulatory framework, corporate social responsibility strategies of development companies, and the capacity of local communities. Stakeholder engagement is essential in initiating and designing benefit sharing programs. This guide provides some advice to task teams on how to design effective local benefit sharing mechanisms in hydropower projects. Benefit sharing arrangements would ensure that local communities have the opportunity to benefit directly from hydropower development...

Meeting the Balance of Electricity Supply and Demand in Latin America and the Caribbean

Yepez-Garcia, Rigoberto Ariel; Johnson, Todd M.; Andres, Luis Alberto
Fonte: World Bank Publicador: World Bank
Tipo: Publications & Research :: Publication; Publications & Research :: Publication
ENGLISH
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45.96%
Economic growth in the Latin America and the Caribbean region has picked up considerably during the past decade or so. This growth has been aided by widespread (earlier and more recent) investments in power generation, transmission, and distribution that increased the provision of electricity services to households, commerce, and industry. This report evaluates a number of critical issues for the power sector in the region in the coming two decades. These include the expected rates of increase in the demand for electricity, the required supply of new generating capacity, the technology and fuel mix of that generating capacity, and the carbon dioxide emissions of the sector. One of the key contributions of this study is the aggregation of individual country plans to the regional and sub regional levels, using a consistent set of data and a common methodology. The report also assesses the important roles of hydropower and natural gas, the way other clean and low-carbon resources can be expanded, the potential and benefits of greater electricity trade...

The Zambezi River Basin : A Multi-Sector Investment Opportunities Analysis - Summary Report; A bacia do rio Zambeze : analise das oportunidades de investimento multissectorial

World Bank
Fonte: World Bank Publicador: World Bank
Tipo: Economic & Sector Work :: Investment Climate Assessment (ICA)
ENGLISH
Relevância na Pesquisa
46.18%
The Zambezi River Basin (ZRB) is one of the most diverse and valuable natural resources in Africa. Its waters are critical to sustainable economic growth and poverty reduction in the region. The overall objective of the Zambezi River Multi-Sector Investment Opportunity Analysis (MSIOA) is to illustrate the benefits of cooperation among the riparian countries in the ZRB through a multi-sectoral economic evaluation of water resources development, management options and scenarios from both national and basin-wide perspectives. Better management and cooperative development of the Basin's water resources could significantly increase agricultural yields, hydropower outputs, and economic opportunities. Collaboration has the potential to increase the efficiency of water use, strengthen environmental sustainability, improve regulation of the demands made on natural resources, and enable greater mitigation of the impact of droughts and floods. Seen in this light, cooperative river basin development and management not only provide a mechanism for increasing the productivity and sustainability of the river system...

The Zambezi River Basin : A Multi-Sector Investment Opportunities Analysis - Basin Development Scenarios; A bacia do rio Zambeze : analise das oportunidades de investimento multissectorial

World Bank
Fonte: World Bank Publicador: World Bank
Tipo: Economic & Sector Work :: Investment Climate Assessment (ICA)
ENGLISH
Relevância na Pesquisa
46.17%
The Zambezi River Basin (ZRB) is one of the most diverse and valuable natural resources in Africa. Its waters are critical to sustainable economic growth and poverty reduction in the region. The overall objective of the Zambezi River Multi-Sector Investment Opportunity Analysis (MSIOA) is to illustrate the benefits of cooperation among the riparian countries in the ZRB through a multi-sectoral economic evaluation of water resources development, management options and scenarios from both national and basin-wide perspectives. Better management and cooperative development of the Basin's water resources could significantly increase agricultural yields, hydropower outputs, and economic opportunities. Collaboration has the potential to increase the efficiency of water use, strengthen environmental sustainability, improve regulation of the demands made on natural resources, and enable greater mitigation of the impact of droughts and floods. Seen in this light, cooperative river basin development and management not only provide a mechanism for increasing the productivity and sustainability of the river system...

The Zambezi River Basin : A Multi-Sector Investment Opportunities Analysis - Modeling, Analysis, and Input Data; A bacia do rio Zambeze : analise das oportunidades de investimento multissectorial

World Bank
Fonte: World Bank Publicador: World Bank
Tipo: Economic & Sector Work :: Investment Climate Assessment (ICA)
ENGLISH
Relevância na Pesquisa
56.22%
The Zambezi River Basin (ZRB) is one of the most diverse and valuable natural resources in Africa. Its waters are critical to sustainable economic growth and poverty reduction in the region. The overall objective of the Zambezi River Multi-Sector Investment Opportunity Analysis (MSIOA) is to illustrate the benefits of cooperation among the riparian countries in the ZRB through a multi-sectoral economic evaluation of water resources development, management options and scenarios from both national and basin-wide perspectives. Better management and cooperative development of the Basin's water resources could significantly increase agricultural yields, hydropower outputs, and economic opportunities. Collaboration has the potential to increase the efficiency of water use, strengthen environmental sustainability, improve regulation of the demands made on natural resources, and enable greater mitigation of the impact of droughts and floods. Seen in this light, cooperative river basin development and management not only provide a mechanism for increasing the productivity and sustainability of the river system...

The Zambezi River Basin : A Multi-Sector Investment Opportunities Analysis - State of the Basin; A bacia do rio Zambeze : analise das oportunidades de investimento multissectorial

World Bank
Fonte: World Bank Publicador: World Bank
Tipo: Economic & Sector Work :: Investment Climate Assessment (ICA)
ENGLISH
Relevância na Pesquisa
56.17%
The Zambezi River Basin (ZRB) is one of the most diverse and valuable natural resources in Africa. Its waters are critical to sustainable economic growth and poverty reduction in the region. The overall objective of the Zambezi River Multi-Sector Investment Opportunity Analysis (MSIOA) is to illustrate the benefits of cooperation among the riparian countries in the ZRB through a multi-sectoral economic evaluation of water resources development, management options and scenarios from both national and basin-wide perspectives. Better management and cooperative development of the Basin's water resources could significantly increase agricultural yields, hydropower outputs, and economic opportunities. Collaboration has the potential to increase the efficiency of water use, strengthen environmental sustainability, improve regulation of the demands made on natural resources, and enable greater mitigation of the impact of droughts and floods. Seen in this light, cooperative river basin development and management not only provide a mechanism for increasing the productivity and sustainability of the river system...

The Welfare Impact of Rural Electrification : A Reassessment of the Costs and Benefits

Independent Evaluation Group
Fonte: Washington, DC : World Bank Publicador: Washington, DC : World Bank
Tipo: Publications & Research :: Publication; Publications & Research :: Publication
ENGLISH; EN_US
Relevância na Pesquisa
45.82%
It has long been claimed that rural electrification greatly improves the quality of life. Lighting alone brings benefits such as increased study time and improved study environment for school children, extended hours for small businesses, and greater security. But electrification brings more than light. It's second most common use is for television, which brings both entertainment and information. The people who live in rural areas greatly appreciate these benefits and are willing to pay for them at levels more than sufficient to cover the costs. However, the evaluation of these and other benefits, as well as of their distribution, has been sparse. This report reviews recent methodological advances made in measuring the benefits of rural electrification (RE) and commends them. It also notes that the understanding of the techniques shown in project documents is sometimes weak, and quality control for the economic analysis in project documents lacking. This study shows that willingness to pay for electricity is high...

Supporting Hydropower : An Overview of the World Bank Group's Engagement

Rex, William; Foster, Vivien; Lyon, Kimberly; Bucknall, Julia; Liden, Rikard
Fonte: World Bank Group, Washington, DC Publicador: World Bank Group, Washington, DC
Tipo: Journal Article; Publications & Research :: Brief; Publications & Research
ENGLISH
Relevância na Pesquisa
66.3%
Hydropower development makes an essential contribution to reducing poverty, boosting shared prosperity, and improving sustainability. Water storage associated with some hydropower projects can also make important contributions to water and food security and to climate resilience. The World Bank Group (WBG) thus uses multiple instruments to support sustainable and responsible hydropower projects of various sizes and types, depending on local need. But hydropower can also carry significant risks that must be carefully managed. Supporting sustainable hydropower is important for the World Bank Group, because hydropower potential exists where electricity is most needed. Hydropower production is the least-cost method of providing electricity in many developing countries. The WBG is committed to helping its clients continuously improve the way they approach hydropower so as to better manage its risks and better share the benefits of this renewable resource. Support for hydropower helps manage risks and can yield local...

Peru : Overcoming the Barriers to Hydropower; Peru - El desarrollo hidroeléctrico en el Peru

World Bank
Fonte: Washington, DC Publicador: Washington, DC
Tipo: Publications & Research :: ESMAP Paper; Publications & Research
ENGLISH; EN_US
Relevância na Pesquisa
56.19%
Hydropower has been the major source of electricity in Peru, traditionally supplying more than 80 percent of electricity requirements, and serving as a source of independent generation for major mines and industries. With the development of natural gas in the early 1990s, and the opening of the Camisea pipeline, the Government of Peru's (GOP's) attention turned to providing incentives for the use of natural gas in power generation. This resulted in a virtual moratorium on hydropower development as a result of the very low price of natural gas (below economic cost). With the development of export markets for gas and increased attention to the impacts of climate change, the Government has recently begun to pay renewed attention to hydropower. Recent developments include: (a) introduction of accelerated depreciation for hydropower investments; (b) introduction of a "discount" to permit hydropower to compete with gas-fired plants in auctions; and (c) announcement of a special hydropower auction to be held in 2009 by ProInversion...

A Hydro-Economic Model for Water Level Fluctuations: Combining Limnology with Economics for Sustainable Development of Hydropower

Hirsch, Philipp Emanuel; Schillinger, Sebastian; Weigt, Hannes; Burkhardt-Holm, Patricia
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
Publicado em 19/12/2014 EN
Relevância na Pesquisa
55.92%
Water level fluctuations in lakes lead to shoreline displacement. The seasonality of flooding or beaching of the littoral area affects nutrient cycling, redox gradients in sediments, and life cycles of aquatic organisms. Despite the ecological importance of water level fluctuations, we still lack a method that assesses water levels in the context of hydropower operations. Water levels in reservoirs are influenced by the operator of a hydropower plant, who discharges water through the turbines or stores water in the reservoir, in a fashion that maximizes profit. This rationale governs the seasonal operation scheme and hence determines the water levels within the boundaries of the reservoir's water balance. For progress towards a sustainable development of hydropower, the benefits of this form of electricity generation have to be weighed against the possible detrimental effects of the anthropogenic water level fluctuations. We developed a hydro-economic model that combines an economic optimization function with hydrological estimators of the water balance of a reservoir. Applying this model allowed us to accurately predict water level fluctuations in a reservoir. The hydro-economic model also allowed for scenario calculation of how water levels change with climate change scenarios and with a change in operating scheme of the reservoir (increase in turbine capacity). Further model development will enable the consideration of a variety of additional parameters...

Should we build more large dams? The actual costs of hydropower megaproject development

Ansar, Atif; Flyvbjerg, Bent; Budzier, Alexander; Lunn, Daniel
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 29/08/2014
Relevância na Pesquisa
45.93%
A brisk building boom of hydropower mega-dams is underway from China to Brazil. Whether benefits of new dams will outweigh costs remains unresolved despite contentious debates. We investigate this question with the "outside view" or "reference class forecasting" based on literature on decision-making under uncertainty in psychology. We find overwhelming evidence that budgets are systematically biased below actual costs of large hydropower dams - excluding inflation, substantial debt servicing, environmental, and social costs. Using the largest and most reliable reference data of its kind and multilevel statistical techniques applied to large dams for the first time, we were successful in fitting parsimonious models to predict cost and schedule overruns. The outside view suggests that in most countries large hydropower dams will be too costly in absolute terms and take too long to build to deliver a positive risk-adjusted return unless suitable risk management measures outlined in this paper can be affordably provided. Policymakers, particularly in developing countries, are advised to prefer agile energy alternatives that can be built over shorter time horizons to energy megaprojects.

Conduit-hydropower potential in the City of Tshwane water distribution system: A discussion of potential applications, financial and other benefits

Loots,I; van Dijk,M; van Vuuren,S J; Bhagwan,J N; Kurtz,A
Fonte: Journal of the South African Institution of Civil Engineering Publicador: Journal of the South African Institution of Civil Engineering
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/10/2014 EN
Relevância na Pesquisa
66.11%
In water distribution networks, water is often fed under gravity from a higher reservoir to another reservoir at a lower level. The residual pressure head at the receiving reservoir is then dissipated through control valves (mechanically or hydraulically actuated), sometimes augmented by orifice plates where there is a propensity for cavitation. There are possibilities to add turbines in parallel and generate hydroelectricity at these locations using the flow and head available. The benefit of this hydropower generating application is that minimal civil works need to be done, as the control valves are normally inside a control room/valve chamber. No negative environmental or social effects require mitigation, and the anticipated lead times should be short. From a topographical perspective the City of Tshwane has a lower elevation than the bulk service reservoirs of Rand Water, which is the main water supply. Water is distributed through a large water system that includes 160 reservoirs, 42 water towers, 10 677 km of pipes and more than 260 pressure reducing stations (PRS) that operate at pressures of up to 250 m. The top ten hydropower potential sites in the City of Tshwane water distribution network have a total energy generating capacity of approximately 10 000 MWh/a. A number of potential conduit-hydropower sites have shown promise of short payback periods. The identifying and development of these sites in Tshwane to convert water pressure to electricity is ongoing and exploited further. Various challenges currently exist with reservoir communication in isolated areas due to vandalism and theft of necessary infrastructure...