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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.
11

Planejamento e Políticas Públicas: uma análise sobre a Gestão Energética Descentralizada em âmbito municipal no Brasil. / Planning and Public Policy: an analysis of the Decentralized Energy Management at the municipal level in Brazil.

Flavia Mendes de Almeida Collaço 30 January 2015 (has links)
A Gestão Energética Descentralizada é uma forma de gestão dos recursos energéticos cujas primeiras publicações referentes ao tema datam dos anos 1980, no entanto, foi verificado um crescimento do desenvolvimento de estudos e aplicações do conceito na prática de forma substancial somente em tempos recentes (anos 2000). A Gestão Energética Descentralizada é tratada sob uma infinidade de termos e conceitos, e também pode ser aplicada com graus diferentes de descentralização como em vilas, quarteirões, bairros, distritos e estados. Tal conceito está fortemente atrelado ao combate das emissões de Gases de Efeito Estufa, busca pela inserção das fontes de energia renováveis nas matrizes, conservação de energia e eficiência energética, e pela associação entre planejamento urbano, ou das cidades, ao dos sistemas energéticos. Ainda, cabe destacar que nesse modelo de gestão descentralizado- a participação popular e o engajamento dos cidadãos nos processos decisórios e na busca por cidades sustentáveis veem sendo colocado, por muitos pesquisadores do tema, como requisitos indispensáveis ao seu adequado funcionamento. Esta dissertação tem como foco de pesquisa a Gestão Energética Descentralizada em âmbito municipal e seu desenvolvimento nas cidades do Brasil. Dessa forma, foi realizada uma revisão bibliográfica sobre o estado da arte do desenvolvimento da Gestão Energética Descentralizada Municipal no Brasil e no mundo, abarcando principalmente questões do planejamento e de políticas públicas como transparência e participação popular no desenvolvimento dos Planejamentos Energéticos Locais. O resultado da pesquisa mostra que existe Gestão de Energia Descentralizada Municipal no Brasil com desenvolvimento de Planejamentos Energéticos Municipais, os quais têm como principal instrumento incentivador o subprograma PROCEL-GEM, foco de estudo de caso também desenvolvido nessa pesquisa, que demonstrou que os planejamentos realizados dentro do subprograma estão restritos as unidades consumidoras de energia elétrica dos órgãos e serviços públicos, além disso, foram observados indícios de falta de transparência e participação popular nos processos de planejamento, assim como falta de recursos para a implementação dos projetos formulados em tais documentos. / Early publications on Decentralized Energy Management, which is a form of energy resources management, date back to the 1980s, however, a substantial increase in the development of such studies and applications of the concept was verified only in recent times (2000s). The Decentralized Energy Management is treated under a multitude of terms and concepts, and can also be applied with varying degrees of decentralization such as in villages, blocks, neighborhoods, districts and states. This concept is close linked to themes like Greenhouse Gases mitigation, integration of renewable energy sources in the energy matrix, energy conservation, energy efficiency and the relationship between urban planning and the energy system. It is noteworthy that in this management model decentralized the communitys participation and engagement in the decision making in the development of sustainable cities is being pointed out, by many researchers, as an indispensable requirement for the proper functioning of this kind of model. This dissertation focuses on Decentralized Energy Management at the municipal level and its development in the cities of Brazil. Thus, this work performs a state of art review on Decentralized Municipal Energy Management in Brazil as well as in the world, covering mainly planning and public policy issues such as transparency and community participation in the development of local Energy Planning. The results shows that there are Decentralized Municipal Energy Management projects in Brazil which develop Municipal Energy Planning, mostly supported by the PROCEL GEM-subprogram, that is also the case study of this research. Additionally, the results demonstrated that the planning made within this subprogram is restricted to the electricity consumption of public agencies or services. Moreover, were observed indications of a lack of transparency and community participation in the planning process as well as the lack of resources for the implementation of such projects.
12

Análise integrada do sistema energético urbano: estudo de caso da cidade de Porto Alegre / Integrated analysis of the urban energy system: case study of the city of Porto Alegre

Natália de Assis Brasil Weber 20 March 2017 (has links)
Nos dias atuais as cidades são o epicentro de uma transformação energética, pois, são elas as principais consumidoras de matéria e energia. Energia fornecida, em sua maioria, através de um sistema convencional, centralizado e ineficiente. Dessa forma, são nos centros urbanos que poderão ser melhor implementadas estratégicas de eficiência energética e conservação de energia. Contudo, antes que os municípios se comprometam com novas iniciativas políticas e investimentos, o primeiro passo é melhorar a compreensão do sistema energético local. Por conseguinte, o objetivo central desta pesquisa é compreender de forma mais integrada o sistema energético de uma cidade através da aplicação de uma metodologia de análise. O município escolhido como estudo de caso é Porto Alegre, por ser uma cidade que se comprometeu em estabelecer mudanças para reduzir as emissões dos gases de efeito estufa, contudo, sem ainda possuir um plano de ação definido. A metodologia do trabalho é qualitativa e quantitativa e foi dividida em três etapas principais: a revisão bibliográfica, o desenvolvimento da metodologia de análise do sistema energético urbano e a aplicação da metodologia proposta. A revisão bibliográfica forneceu a base teórica para o desenvolvimento da metodologia de análise do sistema energético urbano. Esta metodologia prevê o levantamento de dados diversos que se complementam e, dessa forma, possibilitam uma análise integrada e mais aprofundada do sistema energético da cidade. Para tanto, a análise do sistema energético foi dividida em três etapas: caracterização municipal, análise da demanda de energia e levantamento da oferta das principais fontes energéticas locais. Para esta última etapa, visando um exercício concreto de avaliação, especificou-se o potencial de produção de eletricidade através do recurso solar. Os principais resultados da análise do sistema energético de Porto Alegre, entre os anos 2005 e 2014, destacam que o consumo de energia cresceu oito vezes mais que o aumento populacional e menos que a metade do PIB da cidade. Igualmente, no mesmo período, a frota de veículos, assim como o consumo de gasolina, aumentou 13 vezes mais que a população. Entre os setores econômicos analisados o setor transporte foi responsável, em 2014, pelo consumo de 60% da demanda final de energia da cidade. Nesse ano, a fonte de energia mais consumida foi a eletricidade, representando 28,1% do consumo final. Ainda analisando os dados de 2014, verificou-se que o consumo de eletricidade per capita de Porto Alegre pode ser considerado alto, 2,58 MWh/per capita, se igualando ao do Brasil e ao de alguns países desenvolvidos. Em relação ao potencial de produção de eletricidade, a partir da fonte solar, estimou-se um potencial de 2.549 GWh/ano, considerando todo o território da cidade, e de 772 GWh, considerando apenas o território que possuem edificações, aproximadamente 30% da cidade. Isto significa que se todos os consumidores residenciais e comerciais produzissem sua própria energia poderiam ser gerados 2.892 GWh por ano em Porto Alegre. Essa energia seria capaz de suprir 75,8% de toda a demanda de eletricidade da cidade em 2014. Ao final, ressaltou-se a importância de articular o planejamento energético ao planejamento urbano e ao plano de mobilidade urbana, uma vez que o sistema energético urbano está relacionado com os demais. / Nowadays cities at are the epicenter of an energetic transformation. Today, they are the main consumers of matter and energy. Most of that energy supplied through a conventional, centralized and inefficient system. Thus, it is in urban centers that strategic energy efficiency and energy conservation can be better implemented. However, before municipalities commit to new policy initiatives and investments, the first step is to improve understanding of the local energy system. Therefore, the central objective of this research is to understand in a more integrated way the energy system of a city through the application of a methodology of analysis of an urban energy system. The municipality chosen as a case study is Porto Alegre. It was chosen because is a city that has committed itself to establishing changes to reduce emissions of greenhouse gases, however, it does not have a defined plan of action. The methodology of the work is qualitative and quantitative and was divided into three main stages, among them: literature review, development of the methodology of urban energy system analysis, and application of the proposed methodology. The literature review provided the theoretical basis for the development of the methodology of analysis of the urban energy system. This methodology determines the collection of diverse data that complement each other and, thus, enable an integrated and more in-depth analysis of the city\'s energy system. In order to do so, the analysis of the energy system was divided into three stages: municipal characterization, analysis of the energy demand and survey of the supply of the main local energy sources. For this last stage, aiming a specific evaluation exercise, was specified the potential of electricity production through the solar resource.The main results of the analysis of the energy system of Porto Alegre, between 2005 and 2014, highlight that energy consumption grew eight times more than the population increase and less than half of the city\'s GDP. Also, in the same period, the car fleet grew 13 times more than the population. Among the economic sectors analyzed, the transportation sector was responsible for the consumption of 60% of the final energy demand of the city, in 2014. In that year, the most consumed energy source was electricity, representing 28.1% of final consumption. The per capita electricity consumption in Porto Alegre was considered high, 2.58 MWh/per capita, which equals that of Brazil and some developed countries. Regarding the potential for electricity production, it was determined a potential of 2,549 GWh/year (considering the entire territory of the city), and 772 GWh (considering only the territory that have buildings, approximately 30% of the city). This means that if all residential and commercial consumers produced their own energy could generate 2,892 GWh per year in Porto Alegre. This energy would be able to supply 75.8% of all city electricity demand. In the end, it was emphasized the importance of unifying the energy planning to the urban planning and to the urban mobility plan, since the urban energy system is related to both.
13

Rural Electrification and Societal Impacts on Future Energy Demand in Bolivia: A Case Study in an Altiplano Community

Ålund, Anton January 2017 (has links)
Social variables are a predominant force to community development in rural areas. However, research on how social aspects affect the energy situation as a community expands is to date limited. This study aims explore this void and investigate the following question: “What could be a feasible pathway to reach a sustainable and resilient future state in Micaya, based on the impact of key variables within three different sectors: education, health and production?” In this study, theories and models of rural electrification and scenario analysis are transposed and applied to community operated rural electrification in order to frame development. The investigation is restricted to focus on three social sectors, healthcare, education and production. Current literature confirmed that social aspects are missing in rural electrification programs.  Through interview and discussion with an established expert group important social variables have been identified in the study community. These variables lay the foundation for the scenario building used to define a desirable future in the case study community. It was found that the variables within the production sector are most influential to future developments in the study community.  The study revealed that energy access, especially access to electricity, is an essential condition for the development of rural communities. However, it does not guarantee an increase in productivity or effectiveness in social institutions in the absence of other development programs. The study also concludes that well-planned, carefully implemented rural electrification programs provide enormous benefits to rural people. Once an area has reached a certain level of development, further improvement of societal institutions depends on the availability of a secure and stable energy supply.
14

Distributed Bioenergy Systems For Expanding Rural Electricity Access In Tumkur District, India : A Feasibility Assessment Using GIS, Heuristics And Simulation Models

Deepak, P January 2011 (has links) (PDF)
Energy is an important input for various activities that provide impetus to economic, human and social development of any country. Among all the energy carriers, electricity is the most important and sought after energy carrier for its quality, versatility and ability to perform various technology driven end-use activities. Therefore access to electricity is considered as the single most important indicator determining the energy poverty levels prevailing in a country. Demand for electricity has increased significantly, especially in the developing countries, in recent years due to growth in population and intensification of economic activities. Therefore, providing quality and reliable electricity supply at low-cost has become one of the most pressing challenges facing the developing world. Although sufficient efforts have gone into addressing this issue, little progress has been made in finding a satisfactory solution in alleviating this problem. Currently, electricity supply is mostly dependent on centralized large-scale power generation. These centralized systems are strongly supply focused, fossil-fuel intensive, capital intensive, and rely on large-distance transmission and distribution systems. This results in electricity cost becoming unaffordable to the majority poor which comprises more than 70% of the total population in developing countries like India and the benefits of quality energy remaining with the rich, giving rise to inequitable distribution of energy. Continuous exploitation of fossil fuels has also contributed to local and global pollution. Therefore it is necessary to explore alternate means of providing energy access such that the energy carriers are clean, easy to use, environmentally benign and affordable to the majority of the rural poor. India is at a critical juncture of passing through the path of development. India is also in a unique position that its vast majority of rural population is energy poor which is disconnected from the electricity grid. In this context, the proposed research is an attempt towards developing a greater understanding on the issue of rural energy access and providing a possible solution for addressing this gap. This has been proposed to be achieved by adopting a decentralized energy planning approach and distributed energy systems mostly based on renewable energy sources. This is expected to reduce dependence on imported energy, promote self-reliance, provide economically viable energy services for rural applications and be environmentally safe. The focus is limited to biomass energy route which has many advantages; it is a geographically equitably distributed resource, geographical advantage of having potential to setup energy systems at any location where vegetation is present and not seasonal like other renewable energy technologies. A mathematical model-based approach is developed to assess the feasibility of such a proposal. Models are developed for performing biomass resource assessment, estimating end-use-wise hourly demand for electricity, performing capacity and location planning and assessing economic feasibility. This methodological framework was validated through a case study developed for the district of Tumkur in the state of Karnataka (a state in southern region of India). The literature survey was conducted exhaustively covering the whole span of supplyside and demand-side management of electricity systems, and grid-connected and stand-alone power generation systems, their technical, economic and environmental feasibilities. Literature pertinent to GIS applications in biomass assessment, facility location planning and scheduling models were also reviewed to discern how optimal capacity, location and economic dispatch strategy was formulated. Through the literature survey it was understood that there were very few attempts to integrate both demand-side management and supply-side management aspects in the rural energy context. GIS based mathematical models were sparsely used in rural energy planning and decision making. The current research is an attempt to bridge these gaps. The focus in this study is on effectively utilizing the locally available biomass resource. Assessment of Biomass Potential for Power Generation As a first step, the supply option was studied at village level by overlaying LULC (land use land cover) and village boundary GIS maps of Tumkur district. The result was fortified by the NDVI results from remote sensing images of land use pattern in Tumkur district. A detailed village-level assessment of wasteland potential was made for the entire district. The result showed which shows that in Tumkur district, roughly 17.3% of total geographical land was under exploitable wasteland. Using secondary data and literature, biomass potential indices were prepared for different wasteland types to determine the total biomass potential for power generation. The results based on the GIS data the assessment shows that Tumkur has roughly 17.3% of exploitable wasteland. A complete village-level annual power generation potential was assessed considering both energy plantations from wasteland, existing degraded forests and crop residues. Assessment of end-use-wise hourly Demand for Electricity at Village Level Household survey was conducted for 170 sample households randomly chosen from 15 villages, again randomly selected to represent different socio-economic categories. Using statistical tools like k-means clustering, one-way ANOVA and Tukey’s HSD test, first the households were classified into three economic categories to study the distribution of the households in each sample village. Later based on the number of households of each type in a village, the villages were further classified into five groups based on their socio-economic status. This was done to select the right representative per-household power demand for a village of any particular socioeconomic category. The representative per household power demand in each economic category along with secondary data helped in deriving the electricity daily load profiles for all the villages. Representative demand profiles were generated for different seasons across different sectors namely domestic, agriculture and industry sectors at the end-use level comprising of activities like home lighting, appliances, irrigation pump sets operation and small industry operations. Mathematical Modeling for Optimal Siting of Biomass Energy Systems Since the power has to be generated through biomass route, biomass may have to be transported over a large geographical area which requires efficient design of logistic systems. Apart from that, a major component of cost of biomass power is the cost of transportation of biomass from source to the power plant. Therefore it is important to determine the optimal siting of biomass energy systems to minimize the cost of transportation. Since these optimal locations are based on minimizing Euclidian distance, installing the power generation systems at these locations would also minimize total cost of local transmission and distribution. In order to locate the biomass energy system, K-medoid clustering algorithm was used to determine the optimal number of clusters of villages to minimize the Euclidean distance between the medoid of the cluster and the villages within the cluster, and minimize the total installed capacity to meet the cluster demand. The clustering algorithm was modified in such a way that the total capital cost of the power generation system installation was minimized. Since the total project cost not only depended on capital cost alone, but also on biomass transportation and power transmission costs, these costs were also included in the analysis. It was proposed to locate the energy systems at the medoids of the clusters. Optimal Capacity Planning Installing biomass power systems requires large investments. It is therefore necessary to reduce the peak demand to bring down the installed capacity required. This was achieved by developing heuristics to arrive at an optimal scheduling scheme of the end-use activities that would minimize the peak demand. The heuristics procedure was demonstrated on five representative villages, each from different economic category. The optimal demand profile was used as input in HOMER micro-energy system simulation software to perform a techno-economic analysis. The simulation facilitated a thorough economic feasibility study of the system. This included a complete analysis of the cash inflows and outflows, capital cost of the system, operation and maintenance cost, cost of fuel and estimation of total GHG emissions. There are many limitations in planning at village-scale. The results indicated that capacity planning done at the village level was prone to over-estimation of installed capacity of the system increasing the investment requirement, under utilization of the capacity and suffered from supply scarcity of biomass. This emphasized the need for looking at a bigger conglomerate of villages in other words cluster of villages. In the next step, the optimal capacity planning was performed for one of the clusters formed using the K-medoid clustering algorithm with the power generation system located at the medoid. For demonstrating the practical feasibility of extending the methodology to cluster level, a cluster with maximum number of villages was chosen from the optimal cluster set in the k-medoid algorithm output. The planning was conducted according to the socioconomic category of the villages in the cluster. Economic implications of Stand-alone (SA) vs Grid-connected (GC) Mode of Operation Other important question that was answered in this analysis was a comparison of GC systems with SA systems. Since extension of grid to a village that is not electrified involved drawing high voltage transmission lines from the nearest grid point, installation of distribution transformers and low transmission lines within the village for distribution. Since these involve high costs it was necessary to study whether or not it is feasible to extend the grid or install a stand-alone system. This question was answered by the breakeven distance for which grid extension becomes more economical than a SA system. For each village breakeven distance varied with the total installed capacity and the operational costs. This helped to compare the GC systems vis-à-vis SA systems from the point of view of economic feasibility. Summary It is necessary that planning and strategies be rational and reasonable for effectively assuaging the rural electrification imbroglio. The current study has highlighted the importance of integrating both demand-side-management and supply-sidemanagement of energy systems in the context of planning for power generation and distribution in rural areas. The key findings in the current study are: • The study showed the feasibility of biomass power systems in meeting the rural electricity needs. • Biomass assessment results showed that, if the power demand could be brought down by replacing the existing appliances with efficient ones (ex. compact fluorescent lamps and improved irrigation pump set valves), Tumkur district has enough biomass potential to meet both the current as well as increased future demands for electricity. • The optimal number of clusters minimizing total capital cost of biomass energy systems, transportation cost of biomass and distribution cost of power, was 96 for Tumkur district. For Kunigal block, the optimal number of clusters was 37 and 32 for supply and demand scenarios 1(BAU -Business As Usual) and 2 (with 10% increase in cropland and 20% increase in demand). • The optimal capacity planning emphasized the importance of clustering of villages for minimizing the total installed capacity. The result also showed that the breakeven distance was the determining factor about the choice of GC vs SA systems. The main contributions of this thesis are: i. Hourly demand pattern was studied to estimate the aggregate demand for electricity at village level for different sectors across various seasons. ii. Village-wise biomass resources potential for power generation was assessed iii. Optimal locations for siting biomass energy systems were identified using k-medoid clustering algorithm iv. An optimal scheduling of end-use activities was planned using heuristics method to minimize the installed capacity v. Optimal location, scheduling plan of end-use activities and optimal capacity were determined for individual villages as well as village clusters vi. The economic implications of grid extension vis-à-vis stand-alone mode of operation of the installed biomass energy systems were studied The generalized, multipronged approach presented in this thesis to effectively integrate both demand-side management and supply-side management in rural energy planning can be implemented for any rural region irrespective of the location. The results emphasized that for efficient demand-side and supply-side management, it is important to plan for clusters of villages than at the individual village level. The results reported in this thesis will help the policy and strategy makers, and governments to achieve rural electrification to a satisfactory extent to ensure continuous, uninterrupted and reliable power supply by determining the clustering strategy, optimal cluster size, optimal scale and siting of decentralized biomass power generation systems.
15

Community Microgrids for Decentralized Energy Demand-Supply Matching : An Inregrated Decision Framework

Ravindra, Kumudhini January 2011 (has links) (PDF)
Energy forms a vital input and critical infrastructure for the economic development of countries and for improving the quality of life of people. Energy is utilized in society through the operation of large socio-technical systems called energy systems. In a growing world, as the focus shifts to better access and use of modern energy sources, there is a rising demand for energy. However, certain externalities result in this demand not being met adequately, especially in developing countries. This constitutes the energy demand – supply matching problem. Load shedding is a response used by distribution utilities in developing countries, to deal with the energy demand – supply problem in the short term and to secure the grid. This response impacts the activities of consumers and entails economic losses. Given this scenario, demand – supply matching becomes a crucial decision making activity. Traditionally demand – supply matching has been carried out by increasing supply centrally in the long term or reducing demand centrally in the short term. Literature shows that these options have not been very effective in solving the demand-supply problem. Gaps in literature also show that the need of the hour is the design of alternate solutions which are tailored to a nation's specific energy service needs in a sustainable way. Microgrids using renewable and clean energy resources and demand side management can be suitable decentralized alternatives to augment the centralized grid based systems and enable demand – supply matching at a local community level. The central research question posed by this thesis is: “How can we reduce the demand – supply gap existing in a community, due to grid insufficiency, using locally available resources and the grid in an optimal way; and thereby facilitate microgrid implementation?” The overall aim of this dissertation is to solve the energy demand – supply matching problem at the community level. It is known that decisions for the creation of energy systems are influenced by several factors. This study focuses on those factors which policy-makers and stakeholders can influence. It proposes an integrated decision framework for the creation of community microgrids. The study looks at several different dimensions of the existing demand – supply problem in a holistic way. The research objectives of this study are: 1. To develop an integrated decision framework that solves the demand – supply matching problem at a community level. 2. To decompose the consumption patterns of the community into end-uses. solar thermal, solar lighting and solar pumps and a combination of these at different capacities. The options feasible for medium income consumers are solar thermal, solar pumps, municipal waste based systems and a combination of these. The options for high income consumers are municipal waste based CHP systems, solar thermal and solar pumps. Residential consumers living in multi-storied buildings also have the options of CHP, micro wind and solar. For cooking, LPG is the single most effective alternative. 3. To identify the ‗best fitting‘ distributed energy system (microgrid), based on the end-use consumption patterns of the community and locally available clean and renewable energy resources, for matching demand – supply at the community level. 4. To facilitate the implementation of microgrids by * Contextualizing the demand – supply matching problem to consider the local social and political environment or landscape, * Studying the economic impact of load shedding and incorporating it into the demand-supply matching problem, and * Presenting multiple decision scenarios, addressing the needs of different stakeholders, to enable dialogue and participative decision making. A multi-stage Integrated Decision Framework (IDF) is developed to solve the demand - supply matching problem in a sequential manner. The first stage in the IDF towards solving the problem is the identification and estimation of the energy needs / end-uses of consumers in a community. This process is called End-use Demand Decomposition (EUDD) and is accomplished by an empirical estimation of consumer electricity demand based on structural and socio-economic factors. An algorithm/ heuristic is also presented to decompose this demand into its constituent end-uses at the community level for the purpose of identifying suitable and optimal alternatives/ augments to grid based electricity. The second stage in the framework is Best Fit DES. This stage involves identifying the “best-fit‘ distributed energy system (microgrid) for the community that optimally matches the energy demand with available forms of supply and provides a schedule for the operation of these various supply options to maximize stakeholder utility. It provides the decision makers with a methodology for identifying the optimal distributed energy resource (DER) mix, capacity and annual operational schedule that “best fits” the given end-use demand profile of consumers in a community and under the constraints of that community such that it meets the needs of the stakeholders. The optimization technique developed is a Mixed Integer Linear Program and is a modification of the DER-CAM™ (Distributed Energy Resources Customer Adoption Model), which is developed by the Environmental Energy Technologies Division, Lawrence Berkeley National Laboratory using the GAMS platform. The third stage is the Community Microgrid Implementation (CMI) stage. The CMI stage of IDF includes three steps. The first one is to contextualize the energy demand and supply for a specific region and the communities within it. This is done by the Energy Landscape Analysis (ELA). The energy landscape analysis attempts to understand the current scenario and develop a baseline for the study. It identifies the potential solutions for the demand - supply problem from a stakeholder perspective. The next step provides a rationale for the creation of community level decentralized energy systems and microgrids from a sustainability perspective. This is done by presenting a theoretical model for outage costs (or load shedding), empirically substantiating it and providing a simulation model to demonstrate the viability for distributed energy systems. Outage cost or the cost of non supply is a variable that can be used to determine the need for alternate systems in the absence/ unavailability of the grid. The final step in the CMI stage is to provide a scenario analysis for the implementation of community microgrids. The scenario analysis step in the framework enlightens decision makers about the baselines and thresholds for the solutions obtained in the “best fit‘ analysis. The first two stages of IDF, EUDD and Best Fit DES, address the problem from a bottom-up perspective. The solution obtained from these stages constitutes the optimal solution from a technical perspective. The third stage CMI is a top-down approach to the problem, which assesses the social and policy parameters. This stage provides a set of satisficing solutions/ scenarios to enable a dialogue between stakeholders to facilitate implementation of microgrids. Thus, IDF follows a hybrid approach to problem solving. The proposed IDF is then used to demonstrate the choice of microgrids for residential communities. In particular, the framework is demonstrated for a typical residential community, Vijayanagar, situated in Bangalore and the findings presented. The End-use Demand Decomposition (EUDD) stage provides the decision makers with a methodology for estimating consumer demand given their socio-economic status, fuel choice and appliance profiles. This is done by the means of a statistical analysis. For this a primary survey of 375 residential households belonging to the LT2a category of BESCOM (Bangalore Electricity Supply Company) was conducted in the Bangalore metropolitan area. The results of the current study show that consumer demand is a function of the variables family income, refrigeration, entertainment, water heating, family size, space cooling, gas use, wood use, kerosene use and space heating. The final regression model (with these variables) can effectively predict up to 60% of the variation in the electricity consumption of a household ln(ElecConsumption) = 0.2880.396*ln(Income)+0.2 66*Refri geration+ 0.708*Entertainment+0.334*WaterHeating+0.047*FamSize+ 0243*SpaceCooling.+580*GasUse+0.421*WoodUse–0.159*KeroseneUse+ 0.568*SpaceHeating ln(ElecConsumption) = 0.406*ln(Income)0.168*Ref rigeration+0.139*Entertainment+ 0.213*WaterHeating+0.114*FamSize+0.121*SpacCooling+0.171*GasUse+ 0.115*WoodUse–0.094*KeroseneUse+0.075*SpaceHeating   The next step of EUDD is to break up the demand into its constituent end-uses. The third step involves aggregating the end-uses at the community level. These two steps are to be performed using a heuristic. The Best Fit DES stage of IDF is demonstrated with data from an urban community in Bangalore. This community is located in an area called Vijayanagar in Bangalore city. Vijayanagar is a mainly a residential area with some pockets of mixed use. Since grid availability is the constraining parameter that yields varying energy availability, this constraint is taken as the criteria for evaluation of the model. The Best Fit DES model is run for different values of the grid availability parameter to study the changes in outputs obtained in DER mix, schedules and overall cost of the system and the results are tabulated. Sensitivity analysis is also performed to study the effect of changing load, price options, fuel costs and technology parameters. The results obtained from the BEST Fit DES model for Vijayanagar illustrate that microgrids and DERs can be a suitable alternative for meeting the demand – supply gap locally. The cost of implementing DERs is the optimal solution. The savings obtained from this option however is less than 1% than the base case due to the subsidized price of grid based electricity. The corresponding costs for different hours of grid availability are higher than the base case, but this is offset by the increased efficiency of the overall system and improved reliability that is obtained in the community due to availability of power 24/7 regardless of the availability of grid based power. If the price of grid power is changed to reflect the true price of electricity, it is shown that DERs continue to be the optimal solution. Also the combination of DERs chosen change with the different levels of non-supply from the grid. For the study community, Vijayanagar, Bangalore, the DERs chosen on the basis of resource availability are mainly discrete DERs. The DERs chosen are the LPG based CHP systems which run as base and intermediate generating systems. The capacity of the discrete DERs selected, depend on the end-use load of the community. Biomass based CHP systems are not chosen by the model as this technology has not reached maturity in an urban setup. Wind and hydro based systems are not selected as these resources are not available in Vijayanagar. The CMI stage of IDF demonstrates the top-down approach to the demand-supply matching problem. For the Energy Landscape Analysis (ELA), Bangalore metropolis was chosen in the study for the purpose of demonstration of the IDF framework. Bangalore consumes 25% of the state electricity supply and its per capita consumption at 1560kWh is higher than the state average of 1230kWh and is 250% more than the Indian average of 612kWh. A stakeholder workshop was conducted to ascertain the business value for clean and renewable energy technologies. From the workshop it was established that significant peak power savings could be obtained with even low penetrations of distributed energy technologies in Bangalore. The feasible options chosen by stakeholders for low income consumers are The second step of CMI is finding an economic rationale for the implementation of community microgrids. It is hypothesized that the ‘The cost of non-supply follows an s-shaped curve similar to a growth curve.’ It is moderated by the consumer income, consumer utility, and time duration of the load shedding. A pre and post event primary survey was conducted to analyze the difference in the pattern of consumer behaviour before and after the implementation of a severe load shedding program by BESCOM during 2009-10. Data was collected from 113 households during February 2009 and July 2010. The analysis proves that there is indeed a significant difference in the number of uninterrupted power systems (inverters) possessed by households. This could be attributed mainly to the power situation in Karnataka during the same period. The data also confirms the nature of the cost of non-supply curve. The third step in CMI is scenario analysis. Four categories of scenarios are developed based on potential interventions. These are business-as-usual, demand side, supply side and demand-supply side. About 21 scenarios are identified and their results compared. Comparing the four categories of scenarios, it is shown that business-as-usual scenarios may result in exacerbation of the demand-supply gap. Demand side interventions result in savings in the total costs for the community, but cannot aid communities with load shedding. Supply side interventions increase the reliability of the energy system for a small additional cost and communities have the opportunity to even meet their energy needs independent of the grid. The combination of both demand and supply side interventions are the best solution alternative for communities, as they enable communities to meet their energy needs 24/7 in a reliable manner and also do it at a lower cost. With an interactive microgrid implementation, communities have the added opportunity to sell back power to the grid for a profit. The thesis concludes with a discussion of the potential use of IDF in policy making, the potential barriers to implementation and minimization strategies. It presents policy recommendations based on the framework developed and the results obtained.
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Voltage Stability and Reactive Power Provision in a Decentralizing Energy System / Spannungshaltung und Blindleistungsmanagement bei zunehmend dezentraler Stromerzeugung - eine techo-ökonomische Analyse

Hinz, Fabian 19 December 2017 (has links) (PDF)
Electricity grids require the ancillary services frequency control, grid operation, re-establishment of supply and voltage stability for a proper operation. Historically, conventional power plants in the transmission grid were the main source providing these services. An increasing share of decentralized renewable energy in the electricity mix causes decreasing dispatch times for conventional power plants and may consequently lead to a partial replacement of these technologies. Decentralized energy sources are technically capable of providing ancillary services. This work focuses on the provision of reactive power for voltage stability from decentralized sources. The aim is to answer the question of how voltage stability and reactive power management can be achieved in a future electricity system with increasing shares of decentralized renewable energy sources in an economical and efficient way. A methodology that takes reactive power and voltage stability in an electricity system into account is developed. It allows for the evaluation of the economic benefits of different reactive power supply options. A non-linear and a linearized techno-economic grid model are formulated for this purpose. The analysis reveals an increasing importance of reactive power from the distribution grid in future development scenarios, in particular if delays in grid extension are taken into account. The bottom-up assessment indicates a savings potential of up to 40 mio. EUR per year if reactive power sources in the distribution grid provide reactive power in a controlled manner. Although these savings constitute only a small portion of the total cost of the electricity system, reactive power from decentralized energy sources contributes to the change towards a system based on renewable energy sources. A comparison of different reactive power remuneration mechanisms shows that a variety of approaches exist that could replace the inflexible mechanisms of obligatory provision and penalized consumption of reactive power that are mostly in place nowadays.
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Voltage Stability and Reactive Power Provision in a Decentralizing Energy System: A Techno-economic Analysis

Hinz, Fabian 06 December 2017 (has links)
Electricity grids require the ancillary services frequency control, grid operation, re-establishment of supply and voltage stability for a proper operation. Historically, conventional power plants in the transmission grid were the main source providing these services. An increasing share of decentralized renewable energy in the electricity mix causes decreasing dispatch times for conventional power plants and may consequently lead to a partial replacement of these technologies. Decentralized energy sources are technically capable of providing ancillary services. This work focuses on the provision of reactive power for voltage stability from decentralized sources. The aim is to answer the question of how voltage stability and reactive power management can be achieved in a future electricity system with increasing shares of decentralized renewable energy sources in an economical and efficient way. A methodology that takes reactive power and voltage stability in an electricity system into account is developed. It allows for the evaluation of the economic benefits of different reactive power supply options. A non-linear and a linearized techno-economic grid model are formulated for this purpose. The analysis reveals an increasing importance of reactive power from the distribution grid in future development scenarios, in particular if delays in grid extension are taken into account. The bottom-up assessment indicates a savings potential of up to 40 mio. EUR per year if reactive power sources in the distribution grid provide reactive power in a controlled manner. Although these savings constitute only a small portion of the total cost of the electricity system, reactive power from decentralized energy sources contributes to the change towards a system based on renewable energy sources. A comparison of different reactive power remuneration mechanisms shows that a variety of approaches exist that could replace the inflexible mechanisms of obligatory provision and penalized consumption of reactive power that are mostly in place nowadays.
18

Interactions of Connected Electric Vehicles with Modern Power Grids in Smart Cities

Alghamdi, Turki 10 August 2021 (has links)
In a smart city, it is vital to provide a clean and green environment by curbing air pollution and greenhouse gas emissions (GHGs) from transportation. As a recent action from many governments aiming to minimize transportation’s pollution upon the climate, new plans have been announced to ban cars with gas engines throughout the world. Therefore, it is anticipated that the presence of electric vehicles (EVs) will grow very fast globally. Consequently, the necessity to establish electric vehicle supply equipment (EVSE) in the smart city through public charging stations is growing incrementally year by year. However, the EV charging process via EVSE which is primarily connected to the power grid will put high pressure upon the centralized power grid, especially during peak demand periods. Increasing the power production of power grid will increase the environmental impact. Therefore, it is fundamental for the smart city to be equipped with a modern power grid to cope with the traditional power grid’s drawbacks. In this thesis, we conduct an in-depth analysis of the problem of EVs’ interaction with the modern power grid in a smart city to manage and control EV charging and discharging processes. We also present various approaches and mechanisms toward identifying and investigating these challenges and requirements to manage the power demand. We propose novel solutions, namely Decentralized-EVSE (D-EVSE), for EVs’ charging and discharging processes based on Renewable Energy Sources (RESs) and an energy storage system. We present two algorithms to manage the interaction between EVs and D-EVSE while maximizing EV drivers’ satisfaction in terms of reducing the waiting time for charging or discharging services and minimizing the stress placed on D-EVSE. We propose an optimization model based on Game Theory (GT) to manage the interaction between EVs and D-EVSE. We name this the decentralized-GT (D-GT) model. This model aims to find the optimal solution for EVs and D-EVSE based on the concept of win-win. We design a decentralized profit maximization algorithm to help D-EVSE take profit from the electricity price variation during the day when selling or buying electricity respectively to EVs or from the grid or EVs as discharging processes. We implement different scenarios to these models and show through analytical and simulation results that our proposed models help to minimize the D-EVSE stress level, increase the D-EVSE sustainability, maximize the D-EVSE profit, as well as maximize EV drivers’ satisfaction and reduce EVs’ waiting time.
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Optimisation of charging strategies and energy storage operation for a solar driven charging station

Gong, Jindan January 2019 (has links)
The Swedish energy sector is undergoing transformational changes. Along with a rapid growth of renewables and a shift towards electromobility, the transformation is expected to bring challenges to the power system in terms of grid instability and capacity deficiency. Integrating distributed renewable electricity production into the electric vehicle (EV) charging infrastructure is a promising solution to overcome those challenges. The feasibility of implementing such a charging infrastructure system in northern Sweden is however uncertain, as the solar resources are scarce in the long winter period. This study aims to maximise the value of a solar powered EV charging station, placed in a workplace environment in Umeå. An integrated system model of the charging station is developed, comprising separate models of a solar PV system, a battery energy storage system (BESS), the workplace EV fleet and the building Växthuset, onto which the charging station will be installed. Three scenarios are developed to study the charging station’s system performance under different EV charging strategies and BESS dispatch strategies. Two additional scenarios are developed to study the potential grid services that the charging station can provide in the winter period. A techno-economic assessment is performed on each scenario’s simulation results, to measure their effect on the charging station’s value. It involves analysing the charging station’s profitability and how well the BESS is utilised by the end of a ten-year project period. The charging station’s grid impact is further assessed by its self-consumption of solar power, peak power demand and the grid energy exchange. The assessed charging station values indicate that the overall grid impact was reduced with dynamic EV charging strategies and that the BESS capacity utilisation was strongly influenced by its dispatch strategy. The charging station further implied a net capital loss under the explored scenarios, even while the dynamic charging strategies brought by a slightly increased economic value. Moreover, the studied winter scenarios showed a great potential for the charging station to provide ancillary services to the local distribution grid while maintaining an efficient BESS capacity utilisation. The winter period’s peak power demand was significantly reduced by optimising the BESS operation to shift peaks in the building’s load profile, and peaks caused by the additional EV charging demand and the EV heaters, to off-peak hours. On this basis, future research is recommended for improved simulations of the charging station operation and to study additional value-added features that the solar driven charging station can bring. / Sveriges energisystem genomgår en omfattande omställning. Förändringar i form av en ökad andel förnybar elproduktion och elektrifieringen av transportsektorn förväntas medföra stora utmaningar för elsystemets nätstabilitet och överföringskapacitet. Att integrera in distribuerad, förnybar elproduktion som en del av laddinfrastrukturen för elfordon ställer sig som en lovande lösning för att möta de väntande utmaningarna. Möjligheterna att tillämpa en sådan lösning i norra Sverige är däremot mindre självklara, då solresurserna är knappa under vintertid. Det här examensarbetet syftar till att maximera nyttan av en soldriven laddstation för elbilar, placerad på ett arbetsplatsområde i Umeå. En integrerad energisystemmodell av laddstationen har skapats, bestående av systemmodeller av solpaneler, ett batterienergilager, arbetsplatsens elbilsflotta samt byggnaden Växthuset, som laddstationen ska anslutas till. Tre scenarier har utformats för att undersöka hur laddstationens prestanda förändras beroende på olika laddstrategier för elbilarna och batterienergilagrets styrning. Ytterligare två scenarier har utvecklats för att utforska möjliga nättjänster som laddstationen kan bistå med under vintertid. Laddstationens värde har vidare bedömts utifrån systemets prestanda i de olika scenarierna. Bedömningen grundar sig på laddstationens lönsamhet och hur välutnyttjat batterienergilagret är efter en kalkylperiod på 10 år, samt på specifika påverkansfaktorer på elnätet. Faktorerna omfattar konsumtionen av egenproducerad el, toppeffektuttaget och nätöverföringarna orsakade av laddstationen. Från värderingen av laddstationen framgår det att de dynamiska laddstrategierna ledde till en, överlag, minskad påverkan på elnätet samt att styrningen av batterienergilagret hade stor inverkan på dess utnyttjandegrad. Laddstationens nettonuvärde förblev negativt i de tre scenarierna, även om de dynamiska laddstrategierna, ökade dess ekonomiska värde till en viss del. Vidare tyder simuleringen av vinterscenarierna på att det finns en stor potential för laddstationen att erbjuda tjänster för lokalnätet och samtidigt nyttiggöra sig av batterienergilagret. Växthusets toppeffektuttag reducerades märkbart genom att optimera batteristyrningen till att flytta effekttoppar orsakade av Växthusets ellastkurva eller elbilarnas laddning och uppvärmning, till de timmar där lasten var lägre. Med detta i bakgrund föreslås vidare studier som fokuserar på den integrerade energisystemmodellen för att förbättra simuleringarna, samt att undersöka möjligheterna till att erbjuda fler nättjänster, som ökar laddstationens mervärde.

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