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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

The role of the forward capacity market in promoting electricity use reduction

Liu, Yingqi January 2017 (has links)
Electricity use reduction is at the heart of an energy policy landscape increasingly defined by climate change, security and affordability. With its potential of peak demand reduction, it can be used as a cost-effective alternative to generation for contributing to capacity adequacy. In many restructured electricity markets, the forward capacity market is established as a solution to ensure capacity adequacy, with some of them allowing electricity use reduction to compete against other resources. To promote electricity use reduction, financial incentives for investment in end-use electric energy efficiency (EE) are crucial. This thesis focuses on one novel approach of relying on the forward capacity market to incentivise electric efficiency investment, which is trialled in the Electricity Demand Reduction (EDR) Pilot in the UK. It aims to examine the role of the forward capacity market in promoting electricity use reduction, by asking two broad research questions: 1) whether the forward capacity market can serve as a primary policy vehicle to give financial incentives to support electricity use reduction; and 2) whether, as one mechanism for ensuring capacity adequacy, it can promote electricity use reduction as a capacity resource. Case studies are conducted of the EDR Pilot, the Great Britain Capacity Market, ISO New England (ISO-NE), PJM and international electric efficiency schemes. They demonstrate that the forward capacity market, with its focus on peak savings and a savings-based approach for providing financial incentives, only plays a minor role in advancing the objective of incentivising investment in electric EE measures. The general design features of the forward capacity market pose higher requirements of participation, which may create barriers for some key customer segments to access financial incentives or target specific efficiency measure. The capacity payment, under the current market structure, may only provide a lukewarm incentive for customers to strengthen their capabilities to access support from the forward capacity market. However, it is valuable to integrate electricity use reduction in the forward capacity market. It is a viable mechanism to reward the capacity value of electricity use reduction, which requires the appropriate definition of capacity product, regulatory support for electricity use reduction and the removal of participation barriers.
2

Análise da eficiência energética e da viabilidade dos ciclos de absorção na frigorificação de cargas / Analysis of energy efficiency and viability of the absorption refrigeration cycle load

Abreu, Ari Ferreira de 06 July 1994 (has links)
Este trabalho aborda a problemática do transporte de carga frigorificada, sob a ótica da eficiência energética da unidade frigorífica. São propostas alternativas para conservação de alimentos, independentemente do frio. Embora incapazes de substituir totalmente o frio, podem ser uma alternativa em vários casos. É analisada a tecnologia de frigorificação atualmente empregada, enfocando custos do sistema, eficiência energética e efeitos da atual tecnologia sobre o meio ambiente. É desenvolvido o projeto preliminar de uma unidade de refrigeração por absorção, que é analisado comparativamente com as unidades por compressão a vapor. Este estudo mostra que o sistema de refrigeração por absorção pode ser viável em muitas aplicações onde não se dispõe de energia térmica ou mecânica. / This study analyses refrigerated freigth transportation, under the scope of refrigeration energy effeciency. There are several alternatives for food conservation, independently of refrigeration. These existing technologies are not capable of completely replacing refrigeration, but they could be utilized in many cases. The refrigeration techonology currently used is analysed, focusing on system costs, energy efficiency and environmental impacts. A preliminary design of an absoption system was done and an analysis was performed comparating it with the compression units. Conclusive analysis of the system will depend of the evaluation of the experimental unit. This study shows that refrigeration by absortion could be viable in various aplications where no electricity or mechanical energy are available.
3

Condições Operacionais para o Desenvolvimento do Mercado de Eficiência Energética no Setor Residencial: O Caso de Cochabamba, Bolívia / Operating Conditions for the Development of Market Efficiency in the Residential Sector: The Case of Cochabamba, Bolivia

Ajhuacho, Jorge Marcial Choque 09 December 1998 (has links)
A próxima década oferece ao mundo um verdadeiro desafio em relação à conservação de várias formas de energia. Para isso, torna-se necessário a cooperação de vários agentes envolvidos no desenvolvimento de um mercado de eficiência energética, tais como, o governo, a agência reguladora, as empresas geradoras de eletricidade, os vendedores de equipamentos, as empresas distribuidoras de eletricidade e os consumidores. O setor residencial da cidade de Cochabamba é responsável por 44% do consumo de energia elétrica, abrange 86.88% dos consumidores do sistema elétrico de Cochabamba e tem uma taxa média de crescimento da demanda de energia elétrica de 8.S% ao ano. Este setor é muito importante e apresenta um grande potencial de conservação de energia elétrica nos três usos finais que apresentam o maior consumo (79%) em Cochabamba: refrigeração, iluminação e aquecimento da água. No presente trabalho, realiza-se a caracterização da demanda de eletricidade por usos finais em um estudo-piloto, com uma metodologia desenvolvida a partir da realização de uma pesquisa de hábitos de consumo e posse de eletrodomésticos. São analisadas as oportunidades que apresentam-se atualmente na Bolívia para viabilizar o desenvolvimento do mercado de tecnologia ecientes em razão da recente restruturação do setor elétrico boliviano que oferece sinais econômicos de mercado para atingir a eficiência econômica no fornecimento elétrico a custo mínimo. Também são analisadas as barreiras que existem na Bolívia para a introdução de tecnologias eficientes no mercado e propõem-se diversas condições que devem estabelecer-se para desenvolver um mercado de eciência energética. Analisam-se as condições operacionais associando ações do agente regulador, dos vendedores de equipamentos das empresas de energia elétrica e dos consumidores para a aceleração da penetração de tecnologias eficientes de uso final disponíveis em outros mercados. / The next decade introduces a real challenge for energy conservation. This will require the cooperation of many actors involved in an energy efficiency market as the government, the regulatory body, the electric power generating companies, the equipment vendors, the electricity distribution companies and the consumers. In the city of Cochabamba, the residential sector uses 44 percent of the total electrical energy consumption and corresponds to 86,88 percent of the electricity users. As the average demand growth rate is 8.5 percent per year, the residential sector has a large potential for electricity conservation because the three most important end-uses (lighting, refrigeration and water heating) consume 79 percent of total electricity in Cochabamba. The present work assesses the electricity end-uses through a pilot study, applying a methodology using a survey on electrical appliances and consumption. The opportunities for development of an energy efficient tecnologies market in Bolivia are also analized as the recent electricy reform is providing economic signals to achieve economic efficiency at the least-cost electricity supply. The barriers to the introduction of energy efficient tecnologies in Bolivia are also considered with the required conditions for development of a market for energy efficiency. For that purpose, the operational conditions includes the role of the regulatory agency, the equipment vendors, the electricity companies and the consumers in order to accelerate the introduction of efficient tecnologies for end uses available in other markets.
4

Life-cycle Cost Evaluation of Building Envelope Energy Retrofits

Maleki, Afarin 17 January 2012 (has links)
Improving the energy efficiency of our existing building stock is attainable by upgrading the building envelope through carrying out various retrofit measures. The objective of this thesis is to evaluate the life-cycle cost implications of energy retrofits for existing buildings. Measures examined include improving insulation and air-tightness with overcladding strategies. The life-cycle costs of the upgrades are determined for an existing building and compared with model energy performance. A life-cycle cost evaluation for the building envelope upgrades is provided, together with the payback period and the projected return on investment (ROI) for two energy escalation rate scenarios. A costbenefit matrix for various over-cladding strategies is provided to facilitate the evaluation of each option. Further, this thesis presents a simplified ROI algorithm to enable owners, architects and engineers to evaluate the cost-benefit of their building envelope retrofit options.
5

Life-cycle Cost Evaluation of Building Envelope Energy Retrofits

Maleki, Afarin 17 January 2012 (has links)
Improving the energy efficiency of our existing building stock is attainable by upgrading the building envelope through carrying out various retrofit measures. The objective of this thesis is to evaluate the life-cycle cost implications of energy retrofits for existing buildings. Measures examined include improving insulation and air-tightness with overcladding strategies. The life-cycle costs of the upgrades are determined for an existing building and compared with model energy performance. A life-cycle cost evaluation for the building envelope upgrades is provided, together with the payback period and the projected return on investment (ROI) for two energy escalation rate scenarios. A costbenefit matrix for various over-cladding strategies is provided to facilitate the evaluation of each option. Further, this thesis presents a simplified ROI algorithm to enable owners, architects and engineers to evaluate the cost-benefit of their building envelope retrofit options.
6

Campus Sustainability Case Study: Analyzing the energy use, cost efficiency, materials, and construction methods of two campus dormitories, and investigating what causes these differences.

Clements, Scott 14 May 2015 (has links)
Sustainable Built Environments Senior Capstone / The subject matter of this report regards the overall efficiency of two University of Arizona Dormitories from a cost, energy, materials, and construction techniques point of view. Essential to this study was also the social habits of residents within the dormitories, and how they effected the energy use. The two dormitories are considered “pre – LEED” as they were built prior to the recent certification system. Both Manzanita – Mohave, and Coronado Residence Halls were examined in a case study, and interview with the Director of Residence Life, Alex Blandeburgo. In the case study portion, the dormitories’ refrigeration, electricity, steam, and water consumption rates were investigated and compared. These 4 energy types were then looked at from a cost perspective. Lastly, the use of sustainable materials was compared, as well as the construction techniques, and design of each dormitory, and how this could affect social habits, as well as energy use in the dorms. There were some very interesting findings that can be taken from this report. To begin, Manzanita – Mohave was deemed the more sustainable dorm, as its overall energy consumption rates per square foot were much lower than Coronado’s (refrigeration, steam, electricity, and water). In addition to this, Manzi – Mo had less of a cost burden on energy, and its construction methods facilitated less energy use. Additionally, the social habits of Coronado’s residents seem to favor much higher energy uses, which were attributed to their response to the construction methods of the Coronado. These essential results and theories were supported by the experiences of Alex Blandeburgo, and quintessentially mean that a residence hall’s energy efficiency is effected more by the residents that live in it and their habits, rather than its construction techniques, or LEED certification.
7

Barriers and opportunities for improving energy efficiency in the social housing sector : case study of E4C's division of housing and mental health

Marchand-Smith, Patrick 18 December 2012 (has links)
Energy efficiency improvements in the social housing sector have the potential to produce a range of environmental and social benefits. These improvements can be produced through retrofits that deliver energy savings or new construction built to a high standard of energetic efficiency. However, implementation of these approaches is hindered by economic and organizational constraints affecting the agencies that provide society with social housing and the governments that support the provision of these services. This thesis builds on the work of other researchers studying these constraints by supplying an in-depth case study from Alberta and a discussion based on its findings. The case study focuses on E4C, a social service agency with several housing projects. Overall, findings matched important themes identified in the academic literature. The in-depth nature of the case study added additional insight to many of these themes. Most barriers are economic in nature and related to a lack of sufficient funding or the up-front costs of energy-saving retrofits. The recommendations presented are based on consideration of the multiple barriers and opportunities faced. Most of these require a considerable investment of time on the part of agencies and would be followed up by capital investments to implement energy-saving changes. Therefore it is important to note that the most significant barrier is commitment, which is one of E4C's central values. This thesis showed that commitment cannot exceed capacity to act. Greater commitment on the part of governments, agencies or society at large could have significant impacts in improving the energy efficiency of buildings in the Albertan, and Canadian, social housing sector.
8

The feasibility of waste heat recovery and energy efficiency assessment in a steel plant

Si, Minxing 20 July 2011 (has links)
Gerdau Manitoba Mill (Gerdau) at Selkirk, Manitoba is one of the biggest energy consumers in the province of Manitoba. This research analysis undertaken at Gerdau evaluated opportunities for energy efficiency, including the following six areas: 1) recovering waste heat to preheat billets, 2) upgrading the charge end in the reheat furnace, 3) recovering waste heat to preheat combustion air in the ladle preheater, 4) replacing direct-fired natural gas heaters with indirect-fired natural gas heaters, 5) Oxyfuel combustion, and 6) “tap to tap time” control in the eccentric bottom tapping (EBT) furnace in the melt shop. As part of this research, end-user distribution was analyzed and energy losses were assessed. An end-use analysis found that the melt shop that includes the EBT furnace is the biggest consumer of electricity consumption (kWh) and electric demand (kVa), which accounted for 68.7% and 73.6 % respectively. The 2010 delay time in the power-off time of EBT furnace at Gerdau was found to be 762.3 hr/yr. Further research to analyze the cause of each downtime at Gerdau is recommended to determine how these unplanned downtime can be reduced in the EBT furnace. The reheat furnace is the biggest natural gas consumer at Gerdau with 437,563 MCF in 2010. Flue gas losses from the reheat furnace are the biggest energy losses in the gross heat distribution with 26,874,657 Btu/hr. Energy losses from hearth and roof by heat transmission are the biggest energy losses in the net heat distribution during operation, which accounted for 8.9%. The average thermal efficiency in the reheat furnace at Gerdau is 58.9% ± 3.6%. Compared to peak capacity, idle and partial operations of the reheat furnace and idling were found to be less efficient. The opportunities that are considered feasible and recommended to Gerdau are: 1) recovering waste heat to preheat billets, 2) upgrading the charge end in the reheat furnace, 3) recovering waste heat to preheat combustion air in the ladle preheater, 4) replacing direct-fired natural gas heaters with indirect-fired natural gas heaters. These are both good for the environment, reducing fuel use and emissions and providing a good payback period and annual savings. Many opportunities are available for reducing energy as provided in Table A, which shows emissions reductions, costs, energy savings and payback. Oxyfuel combustion is not deemed feasible without considering productivity improvement as oxygen cost is more than natural gas saving. A number of incentive programs, including those from Manitoba Hydro, are applicable to Gerdau. However, a number of barriers to accessing these, particularly as regards tax incentive programs, should be explored to see if these barriers can be overcome.
9

The feasibility of waste heat recovery and energy efficiency assessment in a steel plant

Si, Minxing 20 July 2011 (has links)
Gerdau Manitoba Mill (Gerdau) at Selkirk, Manitoba is one of the biggest energy consumers in the province of Manitoba. This research analysis undertaken at Gerdau evaluated opportunities for energy efficiency, including the following six areas: 1) recovering waste heat to preheat billets, 2) upgrading the charge end in the reheat furnace, 3) recovering waste heat to preheat combustion air in the ladle preheater, 4) replacing direct-fired natural gas heaters with indirect-fired natural gas heaters, 5) Oxyfuel combustion, and 6) “tap to tap time” control in the eccentric bottom tapping (EBT) furnace in the melt shop. As part of this research, end-user distribution was analyzed and energy losses were assessed. An end-use analysis found that the melt shop that includes the EBT furnace is the biggest consumer of electricity consumption (kWh) and electric demand (kVa), which accounted for 68.7% and 73.6 % respectively. The 2010 delay time in the power-off time of EBT furnace at Gerdau was found to be 762.3 hr/yr. Further research to analyze the cause of each downtime at Gerdau is recommended to determine how these unplanned downtime can be reduced in the EBT furnace. The reheat furnace is the biggest natural gas consumer at Gerdau with 437,563 MCF in 2010. Flue gas losses from the reheat furnace are the biggest energy losses in the gross heat distribution with 26,874,657 Btu/hr. Energy losses from hearth and roof by heat transmission are the biggest energy losses in the net heat distribution during operation, which accounted for 8.9%. The average thermal efficiency in the reheat furnace at Gerdau is 58.9% ± 3.6%. Compared to peak capacity, idle and partial operations of the reheat furnace and idling were found to be less efficient. The opportunities that are considered feasible and recommended to Gerdau are: 1) recovering waste heat to preheat billets, 2) upgrading the charge end in the reheat furnace, 3) recovering waste heat to preheat combustion air in the ladle preheater, 4) replacing direct-fired natural gas heaters with indirect-fired natural gas heaters. These are both good for the environment, reducing fuel use and emissions and providing a good payback period and annual savings. Many opportunities are available for reducing energy as provided in Table A, which shows emissions reductions, costs, energy savings and payback. Oxyfuel combustion is not deemed feasible without considering productivity improvement as oxygen cost is more than natural gas saving. A number of incentive programs, including those from Manitoba Hydro, are applicable to Gerdau. However, a number of barriers to accessing these, particularly as regards tax incentive programs, should be explored to see if these barriers can be overcome.
10

An Analysis of Energy Consumption in Grocery Stores in a Hot and Humid Climate

Mukhopadhyay, Jaya 03 October 2013 (has links)
The intent of this study was to investigate the efficient use of energy by developing an energy efficient grocery store combined with cogeneration. This study demonstrated the potential to reduce the energy use in buildings, by implementing a decentralized source of energy generation that allowed for the use of a portion of the energy generated to be shared across building boundaries. This study considered a high energy use building such as a grocery store to be a part of a residential community, which could potentially participate in the sharing of energy across building boundaries. To better utilize energy resources the study proposed the implementation of a cogeneration facility to supply energy primarily to the store. Surplus energy generated by this cogeneration system was then shared with the requirements of the surrounding residential community. Finally, in order to better account for energy consumption of these buildings both site and source energy was considered. The study focused on hot and humid climates. This study was presented in two parts: Analyzing conventional grocery store systems to determine the maximum savings possible; and examining the option of co-generation systems to provide power to grocery stores and a portion of the community in order to reduce source energy use for the grocery store and a portion of the surrounding community. Source energy savings were in the range of 47% to 54% depending on the energy efficiency measures selected and the cogeneration configuration determined in the grocery store. Economic payback periods in the range of 4 to 7 years (time until zero net present value) were observed. The selection of appropriate options was narrowed down to two options that utilized more thermal energy within the boundaries of the store and generated more amount of surplus energy to be absorbed by the neighboring residential buildings.

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