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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.
51

Assessing the performance of demand-side strategies and renewables : cost and energy implications for the residential sector

Bouhou, Nour El Imane 03 September 2015 (has links)
Many public and private entities have heavily invested in efficiency measures and renewable sources to generate energy savings and reduce fossil fuel consumption. Private utilities have invested over $4 billion in energy efficiency with 56% of these investments directed towards consumer incentives. However, the magnitude of the expected savings and the effectiveness of the technological measures remain uncertain. Multiple studies attribute the reasons driving these uncertainties to behavioral phenomena such as “the rebound effect.” This work provides insights on the uncertainties generating potential differences between expected and observed performances of demand-side measures (DSM) and distributed generation strategies, using mixed methods that employ both empirical analyses and engineering economics. This study also provides guidelines to stakeholders to effectively use the benefits from DSM strategies towards asset preservation for affordable multifamily houses. Section 2 describes how joint efficiency gains compare to similar singular efficiency gains for single-family households and discusses the implications of these differences. This work provides empirical models of marginal technical change for multiple residential electricity end-uses, including space conditioning technologies, appliances, devices, and electric vehicles. Results indicate that the relative household level of technological sophistication significantly influences the performance of demand-side measures, particularly the presence of a programmable thermostat. As to space conditioning, results demonstrate that sufficient consistent technical improvement leads to net energy savings, which could be due to technical factors or to a declining marginal rebound effect. Section 3 empirically evaluates the performance of distributed residential photovoltaic (PV) solar panels and identifies the technological and demographic factors influencing PV performance and adoption choice. Results show that modeling PV adoption choice significantly impacts the household energy demand, suggesting that the differences in the actual evaluated behavioral responses and the self-reported changes in electricity consumption are more complex than assumed by other studies. The analysis indicates that electricity use decreases marginally for PV adopters if sufficient efficiency improvements in space conditioning are made. Results further imply that households that adopt solar panels might “take back” roughly 24% of the annual electricity production for PV technologies. Section 4 describes replicable engineering economic models for estimating conventional rehabilitation, energy, and water retrofit costs for low-income multi-family housing units. The purpose of this study is to prioritize policy interventions aimed at maintaining property location and use, and to identify the capital investment needs that could be partially provided by local and state housing authorities. Section 5 synthesizes the work, describes the future work, provides guidelines for local and state efficiency program administrators, and insights on prioritizing and designing efficiency interventions. / text
52

Remote Monitoring of Residential Energy Usage

Tramel, Nathan, Dill, Jacob, Almuqallad, Hussam 10 1900 (has links)
ITC/USA 2013 Conference Proceedings / The Forty-Ninth Annual International Telemetering Conference and Technical Exhibition / October 21-24, 2013 / Bally's Hotel & Convention Center, Las Vegas, NV / A substantial amount of the energy usage in developed countries is consumed by climate control of residential and commercial structures. Collecting information on the usage patterns of heating, ventilation and air conditioning (HVAC) systems can allow a consumer to better understand the cost and effectiveness of these systems, and allow landlords and others to monitor their use. This paper describes a system which can easily be retrofitted onto legacy HVAC systems to monitor their activity, and then transmit the information over a wireless radio network for archiving and analysis
53

How to succeed with energy efficient refurbishment measures : A study of the CONCERTO initiative, BEEM-UP project and EPC model

Wennerberg Fåhraeus, Maja January 2015 (has links)
Buildings consume 40 % of Europe’s total energy consumption and causes 33 % of the CO2 emissions. (Pol and Lippert, 2010) Existing old buildings, especially those constructed with limited energy standards before 1960, are in need of refurbishment and energy efficiency. (Economidou, 2011) The thesis is a part of the EU project GrowSmarter, where smart solutions for sustainable cities are to be implemented in the lighthouse cities Stockholm, Cologne and Barcelona. (European Commission, 2014) The purpose of this thesis is to look into the experiences, success factors and barriers from the CONCERTO initiative, BEEM-UP project and EPC model, focusing on energy efficient refurbishment. The intent is that e.g. authorities, municipalities, companies and building owners, who are planning on performing energy efficient refurbishment measures, can access identified success factors and barriers in previous projects of different scale and methods. The conclusions of this study are that the communication and cooperation between stakeholders in a project, knowledge transfer and training of installers are important factors for successful projects. Information and involvement of tenants facilitates work execution, improves results after refurbishment and increases energy knowledge and awareness. The data quantity and quality is another influencing factor on building performance and the difference between calculated and measured energy savings. Stakeholder approach, energy performance regulations, ownership structure and financial status/possibilities for the building owner can affect project results. / GrowSmarter
54

Analyzing sustainable energy opportunities for a small scale off-grid facility: a case study at Experimental Lakes Area (ELA), Ontario

Duggirala, Bhanu 27 July 2010 (has links)
This thesis explored the opportunities to reduce energy demand and renewable energy feasibility at an off-grid science “community” called the Experimental Lakes Area (ELA) in Ontario. Being off-grid, ELA is completely dependent on diesel and propane fuel supply for all its electrical and heating needs, which makes ELA vulnerable to fluctuating fuel prices. As a result ELA emits a large amount of greenhouse gases (GHG) for its size. Energy efficiency and renewable energy technologies can reduce energy consumption and consequently energy cost, as well as GHG. Energy efficiency was very important to ELA due to the elevated fuel costs at this remote location. Minor upgrades to lighting, equipment and building envelope were able to reduce energy costs and reduce load. Efficient energy saving measures were recommended that save on operating and maintenance costs, namely, changing to LED lights, replacing old equipment like refrigerators and downsizing of ice makers. This resulted in a 4.8% load reduction and subsequently reduced the initial capital cost for biomass by $27,000, by $49,500 for wind power and by $136,500 for solar power. Many alternative energies show promise as potential energy sources to reduce the diesel and propane consumption at ELA including wind energy, solar heating and bio-mass. A biomass based CHP system using the existing diesel generators as back-up has the shortest pay back period of the technologies modeled. The biomass based CHP system has a pay back period of 4.1 years at $0.80 per liter of diesel, as diesel price approaches $ 2.00 per liter the pay back period reduces to 0.9 years, 50% the generation cost compared to present generation costs. Biomass has been successfully tried and tested in many off-grid communities particularly in a small-scale off-grid setting in North America and internationally. Also, the site specific solar and wind data show that ELA has potential to harvest renewable resources and produce heat and power at competitive rates compared to diesel and propane.
55

Firm Behavior, Environmental Externalities and Public Policy

Curtis, Earnest 01 August 2014 (has links)
This dissertation consists of three essays which examine environmental policy, employer mandates and energy consumption. The essays explore how firms respond to government policies such as environmental regulation and employer mandates. Understanding how firms adjust to government policies is crucial to law makers attempting to design optimal policies that maximize net benefits to society. The first essay, titled Who Loses under Power Plant Cap-and-Trade Programs tests how a major cap-and-trade program, known as the NOx Budget Trading Program (NBP), affected labor markets in the region where it was implemented. The cap-and-trade program dramatically decreased levels of NOx emissions and added substantial costs to energy producers. Using a triple-differences approach that takes advantage of the geographic and time variation of the program as well as variation in industry energy-intensity levels, I examine how employment dynamics changed in manufacturing industries whose production process requires high levels of energy. After accounting for a variety of flexible state, county and industry trends, I find that employment in the manufacturing sector dropped by 1.7% as a result of the NBP. Young workers experienced the largest employment declines and earnings of newly hired workers fell after the regulation began. Employment declines are shown to have occurred primarily through decreased hiring rates rather than increased separation rates, thus mitigating the impact on incumbent workers. The second essay, titled Evaluating Workplace Mandates with Flows versus Stocks: An Application to California Paid Family Leave uses an underexploited data set to examine the impact of the California Paid Family Leave program on employment outcomes for young women. Most papers on mandated benefits examine labor outcomes by looking at earnings and employment levels of all workers. Examining these levels will be imprecise if the impacts of the program develop over time and firms are wary to immediately adjust employment and wages for existing workers. Using Quarterly Workforce Indicator data, we are able to measure the impact on hires, new hire earnings, separations and extended leaves among young women. Earnings for young female new hires fell in California relative to other workers, but changed little relative to country-wide comparison groups. We find strong evidence that separations (of at least three months) among young women and the number and shares of young female new hires increased. Many young women that separate (leave the payroll) eventually return to the same firm. Increased separation and hiring rates among young women in the labor market (“churning”) may reflect both increased time spent with children and greater job mobility (i.e., reduced job lock) as the result of mandated paid family leave across the labor market. The third essay, Evidence of an Energy Management Gap in U.S. Manufacturing: Spillovers from Firm Management Practices to Energy Efficiency, merge a well-cited survey of firm management practices into confidential plant level U.S. Census manufacturing data to examine whether generic, i.e. non-energy specific, firm management practices, ”spillover” to enhance energy efficiency in the United States. For U.S. manufacturing plants we find this relationship to be more nuanced than prior research on UK plants. Most management techniques are shown to have beneficial spillovers to energy efficiency, but an emphasis on generic targets, conditional on other management practices, results in spillovers that increase energy intensity. Our specification controls for industry specific effects at a detailed 6-digit NAICS level and finds the relationship between management and energy use to be strongest for firms in energy intensive industries. We interpret the empirical result that generic management practices do not necessarily spillover to improved energy performance as evidence of an “energy management gap.”
56

Energy Efficient RPL Routing Protocol in Smart Buildings

Rezaei, Elnaz January 2014 (has links)
Energy is an important factor that must be considered by multi-hop wireless mesh routing protocols because most sensors are powered by batteries with a limited capacity. We focus on the industry-standard RPL (Routing Protocol over Low-power and lossy networks) routing protocol that must find energy-efficient paths in low-power and lossy networks. However, the existing RPL objective functions route based on hop-count and ETX (expected transmission count) metrics alone, ignoring the energy cost of data transmission and reception. We address this issue in two ways. First, we design an objective function for RPL that finds paths that require, in expectation, the minimum amount of energy. Second, we design a probing mechanism which configures the transmission power of sensors to minimize energy consumption. The proposed approach is implemented and evaluated using simulations as well as on a small testbed with two Zolertial Z1 motes.
57

Analyzing sustainable energy opportunities for a small scale off-grid facility: a case study at Experimental Lakes Area (ELA), Ontario

Duggirala, Bhanu 27 July 2010 (has links)
This thesis explored the opportunities to reduce energy demand and renewable energy feasibility at an off-grid science “community” called the Experimental Lakes Area (ELA) in Ontario. Being off-grid, ELA is completely dependent on diesel and propane fuel supply for all its electrical and heating needs, which makes ELA vulnerable to fluctuating fuel prices. As a result ELA emits a large amount of greenhouse gases (GHG) for its size. Energy efficiency and renewable energy technologies can reduce energy consumption and consequently energy cost, as well as GHG. Energy efficiency was very important to ELA due to the elevated fuel costs at this remote location. Minor upgrades to lighting, equipment and building envelope were able to reduce energy costs and reduce load. Efficient energy saving measures were recommended that save on operating and maintenance costs, namely, changing to LED lights, replacing old equipment like refrigerators and downsizing of ice makers. This resulted in a 4.8% load reduction and subsequently reduced the initial capital cost for biomass by $27,000, by $49,500 for wind power and by $136,500 for solar power. Many alternative energies show promise as potential energy sources to reduce the diesel and propane consumption at ELA including wind energy, solar heating and bio-mass. A biomass based CHP system using the existing diesel generators as back-up has the shortest pay back period of the technologies modeled. The biomass based CHP system has a pay back period of 4.1 years at $0.80 per liter of diesel, as diesel price approaches $ 2.00 per liter the pay back period reduces to 0.9 years, 50% the generation cost compared to present generation costs. Biomass has been successfully tried and tested in many off-grid communities particularly in a small-scale off-grid setting in North America and internationally. Also, the site specific solar and wind data show that ELA has potential to harvest renewable resources and produce heat and power at competitive rates compared to diesel and propane.
58

Maximizing energy savings reliability in BC Hydro industrial Demand-Side Management programs: an assessment of performance incentive models.

Gosman, Nathaniel 29 August 2012 (has links)
For energy utilities faced with expanded jurisdictional energy efficiency requirements and pursuing demand-side management (DSM) incentive programs in the large industrial sector, performance incentive programs can be an effective means to maximize the reliability of planned energy savings. Performance incentive programs balance the objectives of high participation rates with persistent energy savings by: (1) providing financial incentives and resources to minimize constraints to investment in energy efficiency, and (2) requiring that incentive payments be dependent on measured energy savings over time. As BC Hydro increases its DSM initiatives to meet the Clean Energy Act objective to reduce at least 66 per cent of new electricity demand with DSM by 2020, the utility is faced with a higher level of DSM risk, or uncertainties that impact the cost-effective acquisition of planned energy savings. For industrial DSM incentive programs, DSM risk can be broken down into project development and project performance risks. Development risk represents the project ramp-up phase and is the risk that planned energy savings do not materialize due to low customer response to program incentives. Performance risk represents the operational phase and is the risk that planned energy savings do not persist over the effective measure life. DSM project development and performance risks are, in turn, a result of industrial economic, technological and organizational conditions, or DSM risk factors. In the BC large industrial sector, and characteristic of large industrial sectors in general, these DSM risk factors include: (1) capital constraints to investment in energy efficiency, (2) commodity price volatility, (3) limited internal staffing resources to deploy towards energy efficiency, (4) variable load, process-based energy saving potential, and (5) a lack of organizational awareness of an operation’s energy efficiency over time (energy performance). This research assessed the capacity of alternative performance incentive program models to manage DSM risk in BC. Three performance incentive program models were assessed and compared to BC Hydro’s current large industrial DSM incentive program, Power Smart Partners – Transmission Project Incentives, itself a performance incentive-based program. Together, the selected program models represent a continuum of program design and implementation in terms of the schedule and level of incentives provided, the duration and rigour of measurement and verification (M&V), energy efficiency measures targeted and involvement of the private sector. A multi criteria assessment framework was developed to rank the capacity of each program model to manage BC large industrial DSM risk factors. DSM risk management rankings were then compared to program cost-effectiveness, targeted energy savings potential in BC and survey results from BC industrial firms on the program models. The findings indicate that the reliability of DSM energy savings in the BC large industrial sector can be maximized through performance incentive program models that: (1) offer incentives jointly for capital and low-cost operations and maintenance (O&M) measures, (2) allow flexible lead times for project development, (3) utilize rigorous M&V methods capable of measuring variable load, process-based energy savings, (4) use moderate contract lengths that align with effective measure life, and (5) integrate energy management software tools capable of providing energy performance feedback to customers to maximize the persistence of energy savings. While this study focuses exclusively on the BC large industrial sector, the findings of this research have applicability to all energy utilities serving large, energy intensive industrial sectors. / Graduate
59

Interpreting Barriers to Energy Efficiency within Southern Ontario Municipal Buildings: A Case Study

San Filippo, Amanda January 2012 (has links)
Recent concerns regarding climate change, environmental degradation, human health and energy security associated with the consumption of energy have raised questions about the sustainability of current energy systems. Increasing energy efficiency is considered a core strategy for ultimately achieving a sustainable energy system by offering a cost-effective method for reducing energy use for organisations. However, the slow execution of energy efficiency solutions is said to be reflective of a much wider debate within energy economics, and lead to what is commonly referred to as the “efficiency gap”. Historically, the debate involves theoretical differences between engineering-economic, or “bottom-up”, models which suggest there is ample room for profitable energy efficiency measures; and, orthodox economic, or “top-down”, models which argue that there are significant costs associated with reducing energy consumption. The result has been a diversity of opinions on the potential for, and costs of, energy efficiency, the nature and significance of associated barriers and the appropriateness of various policies in overcoming these barriers. In reality, there is no one-size-fits-all solution to resolving the debate. Rather, the differences across energy service markets require that the existence of an efficiency gap be assessed within the context of these parameters. This requires understanding the nature and significance of barriers to energy efficiency and their economic and organisational impacts within various contexts. This paper explores a taxonomy of barriers to energy efficiency within one potentially influential sub-sector within the country’s most densely populated and highest energy consuming region – Southern Ontario municipalities. The information was collected in three phases. First, a review of the literature was conducted which helped identify and understand potential barriers to energy efficiency and the instances in which they would merit policy intervention. Secondly, 26 questionnaires from individuals responsible for various aspects of energy management and municipal decision-making were completed to gain further insight into municipal structures, policies, decision-making procedures and perception of barriers. These questionnaires were supplemented with 6 detailed interviews conducted with municipal energy managers, or the equivalent. The results presented in this study confirm the presence of an energy efficiency gap within the participating municipalities and that barriers to cost-effective energy efficiency measures do in fact exist. These barriers are most often associated with a lack of information on obtaining appropriate measures and difficulties accessing available capital required for initial investments. The findings support the claims of “bottom-up” models which indicate that policy intervention may rationally overcome many of these barriers. For example, organisational policy measures such as the implementation of energy reserve funds for individual departments may be implemented at low costs. Other barriers that do not justify policy intervention, such as risk, were considered to be less relevant to the participating municipalities. The case studies suggest that with adequate public and organisational policy intervention, the energy efficiency gap may be reduced within these municipalities, thus increasing overall energy efficiency.
60

Sistemas de controle solar e ações de retrofitting

Nuss, Claudio Andre January 2018 (has links)
Os sistemas de controle solar auxiliam no controle da radiação solar incidente no envoltório, e, de acordo com a NBR 15220-3, é recomendável seu uso para a zona bioclimática 3, na cidade de Porto Alegre. Assim, com a ação de retrofitting, é possível utilizar os sistemas de controle solar como modo de adaptar o envoltório das edificações ao clima local e aos padrões de consumo atuais. Dessa forma, o retrofitting do envoltório pode contribuir com a redução do consumo energético e a dependência de sistemas de refrigeração e aquecimento mecânico. Logo, o objetivo da dissertação é qualificar e quantificar energeticamente os sistemas de controle solar com vistas à redução do consumo energético nos ambientes construídos. Um estudo de caso foi realizado na cidade de Porto Alegre, onde um edifício foi selecionado perante um conjunto de edificações existentes. Com o auxílio de um método expedito de cálculo energético, foi realizada a avaliação energética do envoltório da edificação atual e do seu retrofitting proposto. A edificação passou de nível energético E para nível A, comprovando o êxito do estudo de retrofitting aplicado. A pesquisa concluiu que, alinhado com o encontrado na revisão da literatura, as edificações com grandes aberturas orientadas para oeste são um equívoco de projeto no clima de Porto Alegre e que as ações de retrofitting são uma alternativa de adaptação ao clima local, tornando os edifícios eficientes energeticamente. / Shading systems help to control the incident solar radiation on the envelope, and, according to NBR 15220-3, its use is recommended for the bioclimatic zone 3, in the city of Porto Alegre. Hence, with retrofitting, it is possible to use shading systems as a way of adapting the building envelope to the local climate and current consumption patterns. Thus, the retrofitting of the envelope can contribute to the reduction of the energy consumption and of the dependence on systems of refrigeration and mechanical heating. Therefore, the objective of this dissertation is to qualify and quantify the energy of shading systems in order to reduce energy consumption in built environments. Thus, a case study was conducted in the city of Porto Alegre, where a building was selected from a set of existing buildings. We performed an energetic evaluation of current envelope of buildings and its proposed retrofitting by using a facilitated method for energy calculation. The buildings moved from energy level E to level A, proving the success of the study on the applied retrofitting. We conclude that, as also shown in literature review; buildings with large openings oriented to the west in Porto Alegre are a design misconception due to the city’s climate. Thus, retrofitting actions are alternative ways to adapt to the local climate so that buildings are energy efficient.

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