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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

Demand side management (DSM) for efficient use of energy in the residential sector in Kuwait : analysis of options and priorities

Al-enezi, Azeez Nawaf January 2010 (has links)
The State of Kuwait has one of the largest per capita consumption in the world, reaching 13061kWh in 2006 (Kuwait MEW, 2007). The power sector in Kuwait is not commercially viable, due to the current under-pricing policy and heavily subsidized tariff. Kuwait needs to take action to meet the increased energy demand. A particular challenge is peak summer demand when extreme heat increases air conditioning loads. Peak demand reached 8900 MW in 2006, with a growth fast at an average rate 5.6% during the last decade. The generated energy reached 47605 GWh in 2006 and is growing fast at an average rate of 6.5%. Electricity demand is characterized by high seasonal variations and low load factor. The main objective of this research is to assess and evaluate the most effective and robust Demand Side Management (DSM) measures that could achieve substantial reductions in peak demand and electricity consumption in the residential sector. The residential sector in Kuwait consumes about 65% of total electricity consumption, and is characterized with inefficient use of energy due to several factors, including very cheap energy price and lack of awareness. To achieve the research objective, an integrated approach was used, including the following steps: • Performing a demand forecast and a building stock forecast across 10 years period (2010 -2019) for the residential sector. The main types of dwellings in Kuwait (villas, apartments and traditional houses) were considered in the forecast. • Conducting detailed energy audits and measurements on selected typical models of residential dwellings. The aim of this process is to examine energy patterns and identify the potential energy efficiency DSM measures. • Performing a simulation process, to evaluate energy performance of the audited dwellings and to estimate the potential DSM savings. Two basic scenarios were considered in simulation, the first represents the base-case with actual existing condition and the second for different DSM options. • Analysis of identified technological DSM options (five) and recommended policy DSM options (two) and ranking them in priority order using the Analytic Hierarchy Process (AHP). • Estimate the potential energy savings and peak demand reductions by the implementation of identified DSM options. A building block approach is used to estimate the aggregate impacts of DSM options and its reflection on the country Load Duration Curve (LDC). The research showed that a DSM portfolio consisting of the seven identified measures, and through a dedicated programme, could have substantial reductions in energy consumption and peak demand. The research showed that the total accumulated energy savings across the forecast period was estimated at approximately 37229 GWh, and the total peak demand reductions during at the end of forecast (2019) reaches 1530 MW representing 8.9% Of the overall peak load. With respect to the type of dwelling, the research also indicated that the total net revenues for the utility were estimated at: $292 million for villas, $79 million for apartments and $47 million for traditional houses. One of the important indicators showed as a result of implementing the identified DSM measures is the positive environmental impact that could be achieved by reducing CO2 total emissions by approximately 26.8 million tonne, which could achieve an annual income of about $38.9 million. Integrated DSM policy recommendations were formulated, including gradual tariff adjustment, and more involvement by the utility, or government, in the creation of sustainable DSM programmes.
2

A domestic solar/heat pump heating system incorporating latent and stratified thermal storage

Trinkl, Christoph January 2006 (has links)
Both solar and heat pump heating systems are innovative technologies for sustaining ecological heat generation. They are gaining more and more importance due to the accelerating pace of climate change and the rising cost of limited fossil resources. Against this background, a heating system combining solar thermal collectors, heat pump, stratified thermal storage and water/ice latent heat storage has been investigated. In order to investigate and optimise the heating system, a dynamic system simulation model was developed. On this basis, a fundamental control strategy was derived for the overall co-ordination of the heating system with particular regard to the performance of the two storage tanks. In a simulation study, a fundamental investigation of the heating system configuration was carried out and optimisation derived for the system control as well as the selection of components and their dimensioning. The influence of different parameters on the system performance was identified, where the collector area and the latent heat storage volume were found to be the predominant parameters for system dimensioning. For a modern one-family house, a solar collector area of 30m² and a latent heat store volume of 12.5m³ are proposed. In this configuration, the heating system reaches a seasonal performance factor of 4.6, meaning that 78% of the building’s and users’ heat demand are delivered by solar energy. The results show that the solar / heat pump heating system can give an acceptable performance using up-to-date components in a state-ofthe- art building. A novel but most significant component of the heating system is the latent heat store, working with water / ice as phase change material. For that reason, the store was developed in a systematic manner with special regard to the heat exchangers. Based on a detailed specification and a functional analysis, concept solutions were investigated and evaluated. A sheet matrix heat exchanger was eventually chosen as it fulfils the specialised requirements of the heating system. The heat exchanger’s behaviour and its performance during phase change were analysed in laboratory tests. In addition, a storage tank design was developed and a preliminary storage dimensioning carried out for the heating system as defined by the simulations, showing that five polymer tanks with 3.3m³ each and 14 sheet matrix heat exchangers in each tank are required.
3

Social capital and the diffusion of energy-reducing innovations in UK households

McMichael, M. H. January 2011 (has links)
Research is presented on the influence of context-specific social capital in the diffusion of energy-reducing innovations within UK communities. This is motivated by the UK government’s policy priority areas of climate change and energy use in the domestic sector. There is currently little evidence that standard technology and behavioural innovations will be adopted widely enough by householders in time to achieve Government energy efficiency targets. Accelerating rates of adoption are therefore important. Diffusion of innovation theory states that the communication of information on innovations through a social system encourages adoption. Social capital theory states that interpersonal communication is a key means of gaining resources, such as energy efficiency information, for attaining certain goals. There are no known previous empirical studies specifically examining the influence of social capital on information diffusion regarding the adoption of household energy efficiency measures in the UK. Using a multi-case case study research design and mixed methods approach, three British communities were surveyed, the quantitative findings of which were contextualised by qualitative focus group findings. The results show that social capital was used most often with newer innovations that were being promoted by an energy company through weakly-tied social network members. Respondents generally did not indicate seeking more information from people in the community than outside of it, but did indicate trusting information from local energy efficiency intermediaries. The findings show that while standard campaigns may account for two-thirds of information seeking behaviour, they may not be addressing up to one-third of information-seekers who would prefer to speak to people they know. Findings also show that there are important differences to recognise between types of innovations and communities, and that tailoring campaigns to communities’ communication channels is imperative. These findings have important implications for informing future community-based energy efficiency programmes.
4

Local projects for sustainable energy : exploring the nature of success

Collins, Beck January 2014 (has links)
Exploring the Nature of Success in Local Projects for Sustainable Energy This research presents an understanding of the nature of success, and the problematic nature of local projects for sustainable energy. Sustainable energy is a critical issue in the UK to alleviate climate change, energy insecurity and energy poverty. Literature is reviewed from three different disciplines; socio-technical systems, behaviour change, and elements of planning literature including governance, communities and sustainability. The review demonstrates that success for such projects is difficult to achieve because energy is provided through an embedded sociotechnical system which being inert is resistant to change; because energy behaviour is complex and hard to alter, and because local projects are difficult to implement. Two Birmingham projects were used as longitudinal case studies; one led by the local authority and one by a voluntary community group representing different approaches to sustainable energy. In both projects, energy efficiency and/or microgeneration technologies were installed and were followed over a period of 18-20 months. Monthly board meetings were attended, documents were studied and 62 interviews were carried out with the beneficiaries of the projects and the project organisers, at two points in time. The nature of success in both projects was explored, as meanings and priorities ebbed and flowed over the course of their lifetimes. In both projects many causative beliefs were found which defined the problems that each project was trying to solve, the solutions to those problems, and hence the nature of success. This needs to be understood at many levels; at the level of the individual, the level of the group delivering the projects, and at the level of society, or the social system. Failure at one level or in one aspect of the problem does not preclude success at another level or in another aspect. Success can include the achievement of behaviour change, system change or the installation of appropriate technologies, and the achievement of the delivery of locally acceptable projects. However success also includes the resolution of particular local issues, which colour local projects for sustainable energy. Thus, ‘success’ means many things on many levels, as the problem faced by local projects for sustainable energy is multi-faceted, multi-level, complex and holistic, and because these meanings change and become more or less salient during the life of a project. Those projects which can explicitly promote and manage these different successes have more chance of being viewed positively. The current literature does not address these issues, and hence does not fully represent how these projects progress and are portrayed. This is essential if local projects are to be built upon, to create a sustainable energy future.
5

Benchmarking the energy performance of the UK non-domestic stock : a schools case study

Hong, S. M. January 2015 (has links)
Lack of awareness of building performance is often highlighted as a key barrier to improving the operational energy efficiency of non-domestic buildings. In 2008, the Display Energy Certificate (DEC) scheme was implemented in the UK to raise awareness and encourage higher levels of energy efficiency in public sector buildings. The thesis reports a review of the energy benchmarks that underpin the DEC scheme, which reveals that they are no longer appropriate for providing useful or relevant feedback. The research therefore aims to improve understanding of the energy performance of non-domestic buildings, and to explore ways in which their operational energy efficiency can be benchmarked with greater robustness. The research comprises four phases of analysis within which data of varying granularity are analysed to acquire a holistic understanding of the patterns of energy use in English schools and the factors that influence their energy demand. First, the latest DEC records are analysed to assess the robustness of the scheme. Second, the patterns of energy use in primary and secondary schools are analysed in greater detail. Third, multiple regression analyses of energy use in relation to intrinsic building and occupant characteristics are carried out. Last, detailed information about the end-use energy consumption of a small number of modern secondary schools is analysed. The main findings reveal shortcomings of the DEC scheme. The results highlight two key issues associated with the classification system: inappropriate levels of aggregation and misclassification of buildings. Energy benchmarks are found to be inappropriate and out-of-date for the majority of benchmark categories. Correlations between intrinsic features and empirical data on the energy performance of schools were found. The research concludes that the DEC scheme lacks robustness, and that its robustness could be improved by refining the classification system based on empirical data, introducing a framework for keeping up-to-date with the latest trends in energy performance, and producing benchmarks that are relevant to the circumstances of individual buildings.
6

Understanding the field performance of domestic heat pumps : an analysis of recent residential heat pump field trials and training needs

Gleeson, C. P. January 2014 (has links)
This thesis explores heat pump performance. Renewable technology, based on ambient conditions, is at a distinct thermodynamic disadvantage when compared with such technologies as gas condensing boilers since the temperature gradients in which they work are so much smaller. This disadvantage makes renewable technologies, and specifically heat pumps, sensitive to design and installation practice. A mixed methods approach of quantitative and qualitative investigation is applied, principally through the analysis of heat pump field trial performance; a meta-analysis of eight European field trials of over 600 heat pump installations in terms of historical and contemporary system boundaries, and a taxonomical analysis of the UK Energy Saving Trust field trial. The trials are placed in context through the analysis of UK central heating practice, UK and EU policy, thermodynamics, manufacturers’ test regimes and a pilot field trial. From this analysis it is apparent that a wide range of performance is exhibited by residential heat pump installations. This potential to underperform, or ‘sensitivity to context’, is explored through its plausible link to vocational education and training (VET). The process of re-aligning EU VET for heat pumps is underway, driven in the UK by the Microgeneration Scheme’s design literature and training requirements. However, doubts remain as to the abilities of current UK contractors to synthesise the technical design requirements given the relatively low educational demands made on residential heating occupations when compared with EUCERT heat pump requirements, more closely aligned with the Continental concept of savoir-faire, 'know-how' or berufliche Handlungsfähigkeit, a multidimensional 'occupational capacity'.
7

Global policy and local outcomes : a political ecology of biofuels in Guatemala

Tomei, J. January 2014 (has links)
The thesis is an investigation of how global processes intersect with local contexts to shape the outcomes of biofuels for different social groups within Guatemala. Its theoretical stance is drawn from political ecology, which argues that phenomena such as the development of biofuels cannot be understood in isolation from the political economic contexts within which they are embedded. The analysis begins with a description of the European Union’s evolving biofuels policy framework. It then turns to an examination of the outcomes in Guatemala, a country that has taken advantage of the opening up of global and specifically European markets for biofuels. The EU is by design one of the few markets to address the sustainability impacts of biofuels and the thesis examines the question of whether its objectives are being met. Since 2006, the production of biofuels, specifically sugarcane ethanol, in Guatemala has increased from almost nil to more than 94 million litres per year in 2011-12. Virtually all of this production was destined for the EU market, which has been an important driver of this growth. This makes Guatemala an excellent case study for examining not only the impacts of increased global demand for biofuels, but also whether sustainability governance, as developed by the EU, adequately captures those issues that are salient to producer country contexts. The main empirical basis of the research is a series of more than seventy interviews, field visits and personal observations drawn from eight months field work in Guatemala. Interviewees ranged from the ex-Minister for Energy to peasant farmers. There are also interviews with EU officials. The thesis argues that given Guatemala’s history of civil conflict, weak governance and unequal land tenure the likelihood of developing an equitable and sustainable biofuels sector as envisioned and understood by European policy actors – one which would deliver rural development and environmental benefits – appears limited.
8

Understanding the interactions between occupants, heating systems and building fabric in the context of energy efficient building fabric retrofit in social housing

Love, J. A. January 2014 (has links)
In order for the UK to meet its 2050 carbon targets there needs to be a major energy efficient retrofit of the UK dwelling stock, of which one fifth is social housing. Evidence suggests that retrofit often leads to an increase in mean internal temperature at the expense of energy savings. Research has quantified this effect but little investigation has taken place regarding why temperature increase occurs. This thesis measures the temperature change after installation of external wall insulation in social housing and attempts to separate out the causal influences of the building fabric and occupant behaviour. A longitudinal mixed physical and social methodology was used to collect data from 13 case study social housing dwellings. Physical variables of air and radiator temperature, relative humidity, secondary heating and use of space were measured in each room in the property, and combined with occupant interviews, in two consecutive winters before and after insulation was applied. Mean internal temperature was observed to increase after retrofit: the majority of this was attributed to insulated properties cooling down more slowly. Observed changes in occupant behaviour consisted mostly of reduction in daily hours of heating, and no occupants increased the thermostat setting. Only a minority of homes purposefully increased their demand for heat. This is contrary to assumptions normally made about occupants deliberately ‘taking back’ energy savings as increased comfort. However, the temperature during heated periods did increase in most dwellings. In several it appeared to have been previously constrained by the ability of the heating system to deliver sufficient heat. The current algorithms for predicting mean internal temperature in models such as SAP and BREDEM are a simplification of the complex physical and social reality in most dwellings. This research gives recommendations as to how domestic heating use could be better modelled and controlled.
9

Developing a method to monitor thermal discomfort response variability

Gauthier, S. M. S. January 2015 (has links)
The need to identify occupants behavioural-responses to thermal discomfort during the heating season has become one of the priorities in the quest to reduce energy demand. The current models have long been associated with peoples behaviour by predicting their state of thermal comfort or rather discomfort. These assume that occupants act upon their level of discomfort through two types of responses: involuntary mechanisms of thermoregulation, and behaviouralresponses. This research seeks to investigate the variability of occupant self-reported and observed behavioural-responses in residential buildings during the heating season. The first part of the research reviews the current standard models and reports on a global sensitivity analysis of the models as described in standards and guidelines. The predictive models appear to be most sensitive to the personal variables, metabolic rate and thermal insulation of clothing. In field studies these personal variables are often estimated with a significant degree of error, and in building simulation studies they are given constant values as a function of the season and the building or room types. To address these two issues, this research introduces a mixed-method framework drawn from psychological and physiological studies. Twenty residents living in nineteen dwellings were monitored over a period of ten consecutive days, in the South-East of England during the winters of 2012 and 2013. Results from this experimental investigation enabled probability distributions for the two personal variables to be drawn. When combining the estimated activity and clothing levels with the environmental monitoring results, the predicted mean votes are substantially below those assumed in standards. This suggests that occupants in this study may be engaging in other adaptive behaviours, not currently accounted for within the standard models. The second part of the research focuses on identifying these adaptive behaviours. One of the key issues is to gather accurate measurements while using discreet observatory methods to have minimum impact on peoples behaviour. Drawing methods from thermal comfort research and psychology, the empirical study undertaken also allows for the creation of a threetiered framework mapping behaviour-responses to cold sensations, consisting of (1) increasing clothing insulation level, (2) increasing operative temperature by turning the heating system on/up, and (3) increasing the frequency, duration and/or amplitude of localised behaviour responses, including for example warm food or drink intake, changing position, changing location within the same room or changing room. Using content analysis and automated segmentation, occupant-self-reported and observed diary responses to cold thermal discomfort were compared, with results showing a marked difference between them. Theoretically, this research introduces a framework to monitor thermal discomfort responses that incorporates a wider range of observed behaviours. Methodologically, this research demonstrates the efficacy of multi-method observational approaches for understanding discomfort responses. Substantively, this research highlights the need for researchers working in this field not to fall into the gap between what occupants say and what occupants do.
10

Energy epidemiology : an epidemiological approach to empirically-based population-level energy demand research

Hamilton, I. G. January 2015 (has links)
The shift to a low carbon economy and the need to address energy demand priorities will involve the retrofit of millions of buildings resulting in changes in energy demand services at the national and international scale. Studying energy demand in buildings at a population level is different than in individual or small samples because of population heterogeneity. Evaluating policies and determining the effect of technologies in situ in millions of buildings means using techniques that support that level of analysis and use empirically derived data that can represent complex real-world conditions. Health epidemiology, which studies the distribution and determinants of population health outcomes, offers a compelling framework for studying population level energy demand. The aim of this thesis is to determine whether the adaption of the conceptual and methodological framework of epidemiology can support the study of energy, people and buildings. This thesis tests this hypothesis by examining relevant epidemiological concepts and its methodological framework along with three studies that adapt and apply epidemiological methods to energy demand and energy efficiency retrofits in UK houses. The method studies use a database of over 13 million dwellings to study energy efficiency retrofit uptake and their impact on energy demand. The method study findings support the case that an epidemiological approach to energy demand provides an appropriate and plausible conceptual and methodological framework for determining population-level evidence to inform modelling and policy development and evaluation. Adapting the epidemiological approach is not a panacea to dealing with the challenges facing the field of research in energy demand in buildings. However, it does provide a set of concepts, methods and analysis tools that are capable of supporting an empirically-based population-level research approach, identified as a necessary step towards to developing a robust foundation of evidence.

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