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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

Battery energy storage for intermittent renewable electricity production : A review and demonstration of energy storage applications permitting higher penetration of renewables / Batterienergilager för intermittent förnyelsebar elproduktion : Litteraturöversikt och demonstrering av användingsområden för att möjliggöra en högre andel förnyelsebar energikällor

Görtz, Steffen January 2015 (has links)
Driven by resource politics and climate change, the transition from conventional fossil fuel based and centralized energy generation to distributed renewables is increasing rapidly. Wind and solar power generation offer carbon dioxide neutral electricity but also present some integration difficulties for energy system operators and planners due to intermittent power output. A promising way of dealing with the intermittency from renewables is energy storage. The method of storing energy in the electricity grid, especially by the means of electrochemical storage, has gained a lot of attention over the last years in the energy sector. While most utilities and energy market stakeholders have the basic understanding of energy storage, a more profound knowledge of grid storage applications is often lacking. This thesis aims to highlight and explain possible energy storage applications with focus on renewables integration. Battery energy storage can allow higher amounts of renewable electricity generation to be integrated by smoothening power output, time shifting generated energy to follow demand and increase hosting capacities through peak shaving. Power quality related issues due to intermittency can be mitigated by controlling the storage’s charging patterns to respond to grid variables. For optimal utilization and maximum storage value, several applications should be within the operational repertoire of the storage unit. Other applications including arbitrage, grid investment deferral and load following are discussed. Several battery technologies which have been developed and tested for such applications including lead acid, sodium sulfate and lithium-ion are presented. The most promising battery energy storage technology is lithium-ion with exceptional storage characteristics and most importantly a favorable near term price development. Two case studies on two of Umeå Energy’s low voltage networks simulating high penetrations of solar generation have been carried out to demonstrate mitigation of overvoltage and peak shaving with battery energy storage systems. The simulations show that energy storage systems can successfully be used to aid the integration of renewables in the electricity grid. Present capital costs are still too high for energy storage to be feasible but falling pricing and a developing market is foreseen to lower the hurdles.  The main obstacle for energy storage at grid scale besides high capital costs are, in principle, non-existing legal frameworks regulating the ownership of energy storage systems and system technology standardization. Further discussions on the matter in combination with testing and pilot projects are needed to gain national and international experience with battery energy storage for the successful high share integration of renewables. / Sinande naturresurser och växthuseffekten driver på övergången från centraliserad kraftproduktion baserad på fossila bränslen till distribuerad förnyelsebar energiproduktion i rask takt. Vind- och solkraft levererar koldioxidneutral el men ställer samtidigt balansansvariga och elnätsplanerare inför en rad problem på grund av periodiskt återkommande och tidvis ostabil effektgenerering. Energilager presenteras som en lovande lösning på problemen orsakade av förnyelsebara energikällor Att lagra energi i elnätet, i synnerhet med batterier, har fått en hel del uppmärksamhet de senaste åren i energibranschen. De flesta elnätsbolag och intressenter på energimarknaden har en grundläggande förståelse kring energilagring i elnätet men saknar ofta mer djupgående kunskap. Detta examensarbete syftar att belysa och förklara användningsområden och potentialer för energilagring med fokus på integreringen av förnyelsebara energikällor. Teorin beskriver hur batterilager kan användas för tillåta integreringen av en hög andel förnyelsebar elproduktion. Några tillämpningar är; effektutjämning, lagring av producerad energi för senare bruk samt ökad nätkapacitet genom att kapa toppar. Problem relaterade till försämrad elkvalité orsakad av varierande kraftproduktion visas kunna pareras med hjälp av programmerbara energilagringssystem som läser av storheter på elnätet såsom spänning och frekvens. För att utnyttja energilagret optimalt och komma åt dess maximala värde bör flera användningsområden kombineras. Därför diskuteras även andra användningsområden såsom arbitrage, lagringskapacitet för att skjuta upp eller undvika förstärkning av elnätet och lastföljning. Ett flertal batteriteknologier aktuella för de diskuterade användningsområdena såsom bly-, natriumsulfat- och litium-jonbatterier presenteras. Den mest lovande teknologin är litium-jon tack vare dess utmärkta egenskaper och framförallt mycket gynnsamma förväntade prisutveckling. Två fallstudier av två av Umeå Energi´s nätområden med hög simulerad andel solenergiproduktion har utförts för att demonstrera utnyttjandet av energilager för reglering av överspänning och kapning av toppar. Simuleringarna visar att energilagringssystem med framgång kan underlätta integreringen av förnyelsebara energikällor. Dagens kapitalkostnader är fortfarande för höga för att energilagring ska vara ekonomiskt försvarbart men fallande priser och en växande marknad väntas verka till teknikens fördel. Det visar sig att regelverk gällande ägandeskapet och standardiseringen av energilager är i det närmaste obefintliga vilket utgör ytterligare hinder för tekniken. Fortsatta diskussioner gällande dessa punkter i kombinationen med test- och pilotanläggningar för att införskaffa erfarenhet av energilagring i elnätet krävs.
2

Evaluating High Penetration of Intermittent Renewable Electricity Policies

Nisal Dinupa Herath (9155576) 23 July 2020 (has links)
<p>Wind and solar generation are intermittent generation sources. System integration costs include the costs of spinning reserves, increased transmission costs and storage costs. The overarching research problem examines evaluation of different policies that lead to high penetration of intermittent renewable electricity sources. The first research question examined the emissions reduction benefits and system integration costs of policy mandates for high penetration of intermittent renewable electricity technologies for Midcontinent Independent System Operator (MISO). The second research question examines the total systems costs of mandates for renewable electricity generation and a carbon tax using a TIMES model for MISO. The third research question examined the emissions and costs of policy mandates for high penetration of wind and solar electricity generation technologies for MISO when short-term operational constraints are considered. TIMES minimizes the total system cost subject to constraints of capacity activity, commodity use, satisfying demand, and peaking reserve. The US EPA 9 region model contains end use technologies for commercial, industrial, residential and transport sectors. The technologies that do not serve end use demands with electricity have been removed. The number of time slices which are the time divisions of the year was increased to 288 to help capture wind and solar generation dynamics at higher levels of penetration and help better understand spinning reserves requirements and costs. Based on the candidate sites for solar and wind generation, the costs include expected transmission costs, and any investment and production costs specific to the candidate sites costs.</p> <p>The results show that as the level of the mandate for wind and solar generation increases, their costs increased. Emissions saving from the mandates were converted to reductions in the Social Costs of Emissions (SCE) (See Section 2.4.4 for the definition) to compare system cost to with the savings in SCE. The savings in the SCE increase as the level of the mandate increases. However, the savings in SCE do not justify the system cost increases associated with the mandates. </p> <p>The carbon tax and mandate policies implemented held the overall emission reductions constant where a 35% reduction of CO2e emissions from 2020 levels by 2050 in compared to the reference scenario. The carbon tax (Policy I) had the lower of Levelized Marginal Cost of Electricity (LMCOE) (discounted value of generation for a year based on the generation weighted Marginal Cost of Electricity), while the mandate (Policy II) had the higher of LMCOE. Similarly, Policy I had the lowest of discounted total system cost and Policy II had higher discounted total system cost. </p> <p>The cost to society is underestimated when short-term operational constraints are ignored. The addition of short-term operational constraints led to increased total systems cost and greater emissions savings as the level of the mandate increased. Adding short-term operating constraints also gives a more complete understating of CO2e emissions savings for the different scenarios as there is a decrease in coal generation and increase in natural gas generation led to increased CO2e emissions savings. The addition of short-term operational constraints shows on one hand the impact of the policy and on the other hand the consequences of not including some of the cost realities.</p>
3

Mapping Scotland's hydropower resource

Duncan, Niall James January 2014 (has links)
Increased renewable electricity generation is key to the reduction of carbon emissions and has the added benefit of reducing reliance on imported gas and coal while increasing diversity of the generation mix. To encourage development of renewable generation the Scottish Government has adopted an ambitious 100% renewable electricity generation target to be met by 2020. Although hydropower has generally been considered insignificant in a UK context, when forming part of a Scottish target the resource becomes much more significant as the majority of the UK’s existing capacity and potential for new capacity is located within Scotland. Scotland has a long history of hydropower development with the majority of current operational capacity installed during the mid 20th century. Recent studies have produced a range of estimates for the remaining resource from 286 to 1000 MW. The studies undertaken have tended to rely upon catchment analogue methods or the use of regression equations to produce estimates of flow at sites of interest, with simple assumptions of installation costs and energy yield. This work uses a novel method combining time series flow data produced from a distributed hydrological model with GIS techniques and a detailed parametric cost model to enable a state-of-the-art hydropower resource model to be developed. The use of time series flow data allowed investigation of the spatial and temporal characteristics of the resource to be made, both run-of-river and impoundment schemes to be investigated and a preliminary assessment of the impact of climate change to be performed. Three financial scenarios have been considered using 5%, 10% and 15% discount rates as this is the most sensitive variable when assessing the feasibility of hydropower projects, reflecting the cost of finance available and investors’ attitude to risk. The spread of discount rates will account for changes in available subsidies, electricity prices and ongoing costs. Clearly availability of low cost finance and a low risk subsidy environment will have the largest impact on hydropower development. A major limiting factor was found to be the cost of grid connection; if this were reduced the potential figure could be higher. The results of this work show that at a 10% discount rate, 440 MW of new run-of river hydropower potential capable of producing 1.7 TWh per year is available. Exploitation of this would represent an additional 4% contribution towards the Scottish Government’s 100% renewable electricity target.
4

Who invests in renewable electricity production? Empirical evidence and suggestions for further research

Bergek, Anna, Mignon, Ingrid, Sundberg, Gunnel January 2013 (has links)
Transforming energy systems to fulfill the needs of a low-carbon economy requires large investments in renewable electricity production (RES-E). Recent literature underlines the need to take a closer look at the composition of the RES-E investor group in order to understand the motives and investment processes of different types of investors. However, existing energy policies generally consider RES-E investments made on a regional or national level, and target investors who evaluate their RES-E investments according to least-cost high-profit criteria. We present empirical evidence to show that RES-E investments are made by a heterogeneous group of investors, that a variety of investors exist and that their formation varies among the different types of renewable sources. This has direct implications for our understanding of the investment process in RES-E and for the study of motives and driving forces of RES-E investors. We introduce a multi-dimensional framework for analyzing differences between categories of investors, which not only considers to the standard economic dimension which is predominant in the contemporary energy literature, but also considers the entrepreneurship, innovation-adoption and institutional dimensions. The framework emphasizes the influence of four main investor-related factors on the investment process which should be studied in future research: motives, background, resources and personal characteristics. / <p>Highlights</p><p>► The RES-E investor group is heterogeneous. ► Investors with no traditional background within electricity production make the majority of RES-E investments in Sweden. ► Different types of RES-E investors invest in different renewables. ► A standard economic perspective is not sufficient to understand emerging RES-E investors. ► Motives, background, resources and personal characteristics of RES-E investors matter.</p> / NYEL - Nya investerare i förnybar elproduktion
5

Consumer Behaviour in Renewable Electricity : Can identity signaling increase demand for renewable electricity?

Hanimann, Raphael January 2013 (has links)
A higher percentage of energy from renewable resources is an important goal on many sustainable development agendas. In liberalized electricity markets, an increase in demand for renewable electricity can stimulate further investments in it, yet demand for renewable electricity has developed much slower than demand for other green products. So far, research has mainly examined the willingness to pay for renewable electricity, but limited research has been conducted to the motivations behind it. The concept of identity signaling has been proved to play a significant role in consumer behaviour for green products. However, (renewable) electricity in the Swedish residential market typically lacks two important drivers for idenity signaling: visibility and product involvement. A survey among Swedish households conducted for this study compares choices for renewable electricity under two scenarios, whereof one simulates a higher visibility of and involvement in electricity contracts. The results show that identity signaling has a positive effect on demand for renewable electricity. The results lead to implications for policy-makers, electricity suppliers and researchers.
6

Inducing large-scale diffusion of innovation : An integrated actor- and system-level approach

Mignon, Ingrid January 2016 (has links)
In order for the innovation process to be successful, not only do innovations need to be developed and reached the market, but, once they are available for users, they have to spread on a large scale. In the innovation literature, a complete explanation is lacking of why some innovations reach a phase of large-scale diffusion faster than others, including both actor- and system-level components. For instance, what drives and hinders adopters to decide to adopt the innovation on the actor and system levels, and how adopters who participate in the largescale diffusion handle the adoption process and the implementation of the innovation, are questions still unanswered. As a consequence, it remains unclear how the large-scale diffusion process can be facilitated and speeded up. This thesis addresses these issues by studying the case of renewable electricity (RE) innovations. After decades of technology development and improvements, RE innovations are now mature enough to be bought off-the-shelf by individuals and organizations. Yet, the pace of their large-scale diffusion is still too slow for countries to reach their RE generation targets and to limit global warming. Through qualitative and quantitative methods including 59 semi-structured interviews with adopters, project developers and experts in Sweden, France and Germany as well as a survey sent to the whole population of RE adopters in Sweden, an adopter perspective is taken in order to explore the adoption dynamics shaping large-scale diffusion of innovation. More specifically, the thesis identifies the drivers and challenges of adoption during large-scale diffusion and their impact on adoption decisions and strategies. The outcome of this work is presented in a compiling synthesis and six appended papers. Findings show that adopters are heterogeneous with regard to their characteristics, as well as to the drivers, challenges and strategies that affect their adoption processes. Depending on their perceptions, some adopters are more influenced by drivers and challenges than others and, as a consequence, adopters base their adoption decisions on different motives and follow different strategies to implement the innovation. Moreover, the results suggest that the dynamics that occur during the large-scale diffusion process does not only come from the actor level and the level of the system where the largescale diffusion takes place, but also from parallel systems, which are related to adopters and their contexts, including both the social networks and the industries they primarily belong. This makes adopters the central drivers of the innovation diffusion process and this distinguishes the dynamics of large-scale diffusion from the dynamics of innovation development and early diffusion, in which the innovation is the central component. Based on the findings about the adoption dynamics shaping large-scale diffusion, the thesis raises the need to consider large-scale diffusion as part of a new system, different from the innovation system and that acknowledges the specificities of this process. A tentative model accounting for the central role of adopters and for the interactions between adopters, the diffusion system and parallel systems is introduced. Finally, the implications of these findings for policy makers and managers are put forward. In particular, there is a need for policies acknowledging adopters’ heterogeneity as well as the new challenges of large-scale diffusion. Strategies developed by adopters can be a source of inspiration for policy-makers, who can for instance promote the use of intermediaries, of adopters’ task environment and networks, as well as the formation of coalitions among adopters.
7

Impactos econômicos e regionais dos investimentos em geração de energia elétrica no Brasil / Economic and regional impacts of investments in electricity generation in Brazil

Diniz, Tiago Barbosa 26 February 2019 (has links)
Para atender os seus compromissos climáticos, o Brasil planeja elevar a participação das fontes renováveis, além da hidrelétrica, na oferta de eletricidade. Segundo o Plano Decenal de Expansão de Energia (PDE 2026), a expansão da capacidade instalada no período 2017-2026 será predominantemente com investimentos na geração à gás, eólica e solar. No entanto, as áreas disponíveis e aptas para tais projetos estão concentradas, em sua maioria, nas regiões com menor PIB per capita, a exemplo da Nordeste, de modo que a expansão da capacidade instalada pode ter implicações econômico-regionais, que podem ser intensificados a depender da configuração da matriz elétrica. Não obstante a importância da temática, ainda há uma evidente lacuna na literatura. Este trabalho, portanto, analisa essa questão com o objetivo de verificar quais os impactos econômicos e regionais dos investimentos em geração de energia elétrica, com base nos cenários de expansão delineados no PDE 2026. Para tanto, é utilizado o TERM-BR10, modelo de equilíbrio geral computável, regional (bottom-up), dinâmico-recursivo e para o qual foi desenvolvido um módulo específico para simulações com o setor elétrico em que são representados oito tipos de geração de eletricidade (eólica, solar, hidráulica, biomassa, térmicas à gás, carvão, diesel e óleo combustível e outras térmicas) e em que se permite a substituição entre os diferentes tipos de geração em nível regional. Para as simulações, assume-se como linha de base a expansão prevista no Caso 8 - Expansão Dirigida, do PDE 2026, por ser a que tem menos interferência de diretrizes políticas. Já as expansões previstas para o Caso 1 (cenário de referência), o Caso 4 (redução no custo de investimento na geração solar) e o Caso 5 (sem novas usinas hidrelétricas) foram adotadas como cenários alternativos. Os resultados obtidos evidenciam que, em relação a linha de base, um plano de expansão com maior inserção de geração solar (Caso 4) pode impactar elevação acumulada de 0,45% no PIB brasileiro e de até 2,15% em regiões específicas, sendo as áreas mais beneficiadas aquelas da região Nordeste do país. Também verifica-se que um cenário sem novas usinas hidrelétricas (UHE) não implica perdas ao Brasil em termos de PIB ou emprego, o que é particularmente relevante face as exigências ambientais cada vez mais rigorosas sob esse tipo de geração. Ademais, foi também observado que as diretrizes de política inseridas nos cenários alternativos do PDE têm benefícios distributivos, com impactos positivos maiores para as regiões mais pobres e famílias com renda mais baixa. / To comply with climate agreements, Brazil intends to raise the share of non-hydro renewables in electricity supply. According to the Brazilian Decennial Energy Plan (PDE 2026), the country will expand its installed capacity in the period 2017-2026 mostly by investments in gas, wind and solar sources. However, areas suitable for those projects are regionally concentrated and, in some cases, in the poorest regions such as the Northeast. Hence, the expansion of power supply also have economic and regional implications that could be enhanced according to the configuration of the electricity matrix. Despite that, there is still a gap in the literature regarding to this topic. We explore this analyzing the economic and regional impacts of the investments in electricity generation, under various policy scenarios provided by the PDE 2026. For that, we apply a regional recursive-dynamic CGE model for Brazil, TERM-BR10, specially enhanced to deal with electricity features. TERM-BR10 has eight electricity generation types (wind, solar, hydropower, biomass, gas, diesel and oil, coal and others) and allows substitution between them in a regional level. For simulation purposes, we assume the expansion of electricity matrix of Case 8 from PDE 2026 as our baseline. In fact, this expansion is the one with less policy interventions. As our policy scenarios we assume: Case 1 (reference scenario), Case 4 (scenario with reduction in cost of investment for solar) and Case 5 (no new hydro dams). Our results show that in comparison to the baseline a supply plan with more insertion of solar source, as Case 4, could increase the national GDP by 0.45% and by 2.15% in specific regions. In this case, the Northeast regions are the most benefited. The results also show that a scenario without new hydro dams does not imply in economic loss, in terms of national GDP or employment. This is quite relevant, specially when take into account that environmental concerns have been raising for hydro projects. Besides, we also came to the conclusion that policy guidelines have welfare and distributive benefits, with greater impact to poorest regions and low income households.
8

Renewable Electricity Policies in the U.S.: A Comparison of Renewable Portfolio Standards and Feed-in Tariffs

Renshaw, Jeffrey S. January 2009 (has links)
Thesis advisor: Frank Gollop / Thesis advisor: James Dalton / There is a push for more electricity from renewable energy sources in the United States and around the world, but debate exists over the best policy to achieve this growth. Two common policies include renewable portfolio standards and feed-in tariffs. Using two Energy Information Administration forecasts from 2005 to 2030, this study examines the impacts of possible federal renewable portfolio standards in the United States through a benefit-costs analysis. Using the same benefit-cost analysis, a feed-in tariff policy in Germany and a unique renewables obligation in the United Kingdom are also examined and the results are compared. This study finds that only one of the four examined policies has a net benefit to society, the policy being a renewable portfolio standard requiring 25% of electricity supplied in the United States to be from renewable energy sources by the year 2025. The economic theory gives support to the superiority of renewable portfolio standards, although more study in needed on the dynamic efficiencies and other possible policy options. / Thesis (BA) — Boston College, 2009. / Submitted to: Boston College. College of Arts and Sciences. / Discipline: College Honors Program. / Discipline: Economics Honors Program. / Discipline: Economics.
9

Influence of Trust Concerns and Benefits of Visibility on Participation in Green Electricity Programs: a Case-Study of Residential Solar-PV Systems in Ontario

Chlobowski, Andrzej January 2013 (has links)
This study examines two of the reasons that prevent people from taking part in green electricity programs: trust concerns that these programs may raise, and lack of benefits that come with visibility of participants’ involvement. While the current literature takes notice of their influence, in this study it was decided to investigate both factors in more detail. In particular, with the help of a survey, the study focused on the reactions of electricity consumers to the proposition of participation in green electricity programs in a controlled setting, in which levels of trust concerns raised and benefits of visibility provided by the programs could be varied. The study was conducted in Oakville, an affluent southern Ontario (Canada) suburb. The results are based on 160 received responses to 500 questionnaires that were sent out by mail. While the results of this study point towards the conclusion that both factors have an influence on participation in green electricity programs, their relative strength cannot be estimated by these results. One can, however, claim that the combined influence of trust concerns and benefits of visibility is quite strong. This research shows that at a 95% confidence level, willingness to participate in a program that proposes paying premium for electricity from solar panels installed on a participant’s roof (low trust concerns, high benefits of visibility) is 30% + 19.3% higher than willingness to participate in a program that proposes paying premium for electricity from undisclosed solar farms (high trust concerns, low benefits of visibility). Additional data about trust concerns, appreciation of benefits of visibility, and concerns about installation of solar panels on one’s own roof, provided by the survey, are also presented in the text. In conclusion, it is recommended that future research should more clearly separate the strength of influence of trust concerns from the influence of benefits of visibility on green electricity program participation. It is also important to study which features of these programs make them more trustworthy and visible. An important implication of this study for policy makers and green electricity proponents is to concentrate on allaying trust concerns, and enhancing benefits of visibility when designing policies or drafting plans for green electricity programs. The creation of an independent green electricity program certification system and a greater accent on the local presence of such programs is suggested.
10

Influence of Trust Concerns and Benefits of Visibility on Participation in Green Electricity Programs: a Case-Study of Residential Solar-PV Systems in Ontario

Chlobowski, Andrzej January 2013 (has links)
This study examines two of the reasons that prevent people from taking part in green electricity programs: trust concerns that these programs may raise, and lack of benefits that come with visibility of participants’ involvement. While the current literature takes notice of their influence, in this study it was decided to investigate both factors in more detail. In particular, with the help of a survey, the study focused on the reactions of electricity consumers to the proposition of participation in green electricity programs in a controlled setting, in which levels of trust concerns raised and benefits of visibility provided by the programs could be varied. The study was conducted in Oakville, an affluent southern Ontario (Canada) suburb. The results are based on 160 received responses to 500 questionnaires that were sent out by mail. While the results of this study point towards the conclusion that both factors have an influence on participation in green electricity programs, their relative strength cannot be estimated by these results. One can, however, claim that the combined influence of trust concerns and benefits of visibility is quite strong. This research shows that at a 95% confidence level, willingness to participate in a program that proposes paying premium for electricity from solar panels installed on a participant’s roof (low trust concerns, high benefits of visibility) is 30% + 19.3% higher than willingness to participate in a program that proposes paying premium for electricity from undisclosed solar farms (high trust concerns, low benefits of visibility). Additional data about trust concerns, appreciation of benefits of visibility, and concerns about installation of solar panels on one’s own roof, provided by the survey, are also presented in the text. In conclusion, it is recommended that future research should more clearly separate the strength of influence of trust concerns from the influence of benefits of visibility on green electricity program participation. It is also important to study which features of these programs make them more trustworthy and visible. An important implication of this study for policy makers and green electricity proponents is to concentrate on allaying trust concerns, and enhancing benefits of visibility when designing policies or drafting plans for green electricity programs. The creation of an independent green electricity program certification system and a greater accent on the local presence of such programs is suggested.

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