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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

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.
3

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.
4

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.
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

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.
7

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.
8

Multimodal sensing for robust and energy-efficient context detection with smart mobile devices

Radu, Valentin January 2017 (has links)
Adoption of smart mobile devices (smartphones, wearables, etc.) is rapidly growing. There are already over 2 billion smartphone users worldwide [1] and the percentage of smartphone users is expected to be over 50% in the next five years [2]. These devices feature rich sensing capabilities which allow inferences about mobile device user’s surroundings and behavior. Multiple and diverse sensors common on such mobile devices facilitate observing the environment from different perspectives, which helps to increase robustness of inferences and enables more complex context detection tasks. Though a larger number of sensing modalities can be beneficial for more accurate and wider mobile context detection, integrating these sensor streams is non-trivial. This thesis presents how multimodal sensor data can be integrated to facilitate ro- bust and energy efficient mobile context detection, considering three important and challenging detection tasks: indoor localization, indoor-outdoor detection and human activity recognition. This thesis presents three methods for multimodal sensor inte- gration, each applied for a different type of context detection task considered in this thesis. These are gradually decreasing in design complexity, starting with a solution based on an engineering approach decomposing context detection to simpler tasks and integrating these with a particle filter for indoor localization. This is followed by man- ual extraction of features from different sensors and using an adaptive machine learn- ing technique called semi-supervised learning for indoor-outdoor detection. Finally, a method using deep neural networks capable of extracting non-intuitive features di- rectly from raw sensor data is used for human activity recognition; this method also provides higher degree of generalization to other context detection tasks. Energy efficiency is an important consideration in general for battery powered mo- bile devices and context detection is no exception. In the various context detection tasks and solutions presented in this thesis, particular attention is paid to this issue by relying largely on sensors that consume low energy and on lightweight computations. Overall, the solutions presented improve on the state of the art in terms of accuracy and robustness while keeping the energy consumption low, making them practical for use on mobile devices.
9

"Study of a direct combustion into steam"

Stefano, Marco, Meglio, Rosamaria January 2013 (has links)
No description available.
10

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.

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