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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.
171

Achieving Universal Access to Electricity through Decentralized Renewable Energy Technologies in Minas Gerais, Brazil

Bulut, Mehmet Börühan January 2012 (has links)
Brazil started the Luz Para Todos (Light for all - LPT) program in 2003 aiming at universalization of electricity access in the country. The program uses three technological solutions to reach this goal: grid extension, decentralized power generation with isolated grids and stand-alone systems. This master thesis analyzes the role of decentralized renewable energy technologies in the Luz Para Todos program in the state of Minas Gerais. The factors that lead to the use of such technologies in the specific case of CEMIG (Energy Company of Minas Gerais) are considered. The study showed that regulatory framework and energy policy mechanisms are the most important determinants of the method of attendance in rural electrification. It is concluded that decentralized renewable energy technologies emerge as a strong alternative when it is not technologically and/or financially feasible to extend the grid.
172

Solar PV based rural electrification in Rema rural village

Admasu, Alemshet Ayele January 2011 (has links)
Energy is a basic need for the overall growth and improvements of people’s living standard.But around 2 to 3 billion people in the world have no access to electric lighting. Like otherdeveloping countries the rural electrification in Ethiopia is very low and government takessome actions to promote the investment in these areas but due to economic constraints andlow level of technological advancement the growth is very low.This study focuses on solar PV based rural electrification, its impact on environment andsocio-economic development in Rema village. Three cases studies: typical households,small scale business center and public services are considered for systematic study.Interviews from villagers, existing energy system, literature data and HOMER software areused to calculate energy demand and cost of electrification. A comparison between theresults is carried out.According to the village survey the existing PV home system has a positive impact on a socioeconomic development of the village of Rema. Solar PV electricity can be used in generatingincomes. It is also used for climate mitigation by curbing CO2 emission and can be used forclimate adaptation by reducing the deforestation and facilitate carbon sequestration. PVbased electrification of health center and schools have played a vital role in improving thequality of services. The presence of refrigerator helped to have vaccines and medicines4preserved for different types of killer diseases. The teaching-learning process of schoolsimproved due the presence of electricity. The solar powered water supply in near areasreduced the time required for fetching water and made girls to focus on their education.Most villagers has positive attitude towards the technology but unsatisfied with the currentsystem size. The high level of technical skills required for maintenance and the small numberof solar technicians’ available in the village is also a problem reported in the village. HOMERsoftware is used to model the existing energy system and the required energy demandbefore PV based rural electrification and after PV based rural electrification. A new model isdeveloped depending on the villagers demand. . Modeling result shows that 3 kWP and 12kWP were found to be enough to fulfill the demand in clinics and schools with an initialinvestment of 18576 and 80704US$, respectively and a PV size of 165 Wp, 250 Wp and 350Wp is required for households with agriculture only, mixed and small scale business income,respectively. This led a requirement of initial capital of US$ 654, 1848 and 2339,respectively. However, these initial investments are unaffordable for most of the villagers.PV systems required for households with agriculture only, has lower investment per Wattthan others, while investment per Watt for small scale business has lower than householdswith mixed type. Therefore, the battery size plays an important role in the investment,operation and maintenance costs.The two main problems associated with solar PV in rural electrification are financial capabilityand technical problems. These problems can be curbed by loan arrangement and trainingthe villagers. But to make sustainable it must be used for income generating activities.
173

Rural electrification using renewable energy resources - Case Study of Rayal, Nepal : Minor Field Study

Beck, Madeleine, Schött, Cecilia January 2013 (has links)
This study has been conducted as a Minor Field Study (MFS) and focuses on the electrification process of Rayal, a remote village in the Far Western Development Region of Nepal. The purpose of the study was to investigate the possibilities of providing electricity based on renewable energy resources to Rayal, both from a technical and a socio-economical point of view. Preliminary research in Sweden was complemented by a field study in Rayal between February and April 2013. Wind power, solar power and micro hydro power were investigated as potential sources of energy. Wind power was considered as unsuitable, due to the low wind speeds in the village as well as poor infrastructure in the country. Solar power and micro hydro power were both calculated based on three different demand scenarios. The results indicate that, depending on the demand and paymentability of the villagers, both solar and micro hydro power could be considered as good options. Solar power is, however, only economically feasible for covering the basic needs of lighting. At higher loads micro hydro power is more economically viable. Excess electricity could be utilized by community facilities, to improve education and health. Alternatively, it could be used to power electrical agricultural equipment which could improve productivity and hence stimulate economic growth in the village. / Denna studie har utförts i form av en Minor Field Study (MFS) och fokuserar på hur en elektrifiering skulle kunna ske av Rayal, en avlägsen by i Far Western Development Region i Nepal. Syftet med studien är att undersöka vilka möjligheter som finns för att elektrifiera Rayal med hjälp av förnyelsebara energikällor, både ur ett tekniskt och från ett socio-ekonomiskt perspektiv. De tre olika teknikerna som har undersökts är vindkraft, solkraft samt småskalig vattenkraft. Vindkraft har uteslutits som lämpligt alternativ, på grund av för låga vindhastigheter i byn, samt bristande infrastruktur i Nepal. Solkraft och vattenkraft har undersökts utifrån tre olika behovs-scenarion. Resultaten visar att, beroende på efterfrågan och betalningsförmågan hos byborna, kan både sol och småskalig vattenkraft betraktas som lämpliga alternativ. Solkraft är dock endast ekonomiskt försvarbart vid mindre projekt, som täcker det grundläggande behovet av belysning. Vid ett större behov är småskalig vattenkraft en mer ekonomisk lösning. Detta ökade behov skulle till exempel kunna vara samhällsförbättrande anläggningar, för att höja utbildnings- och hälsonivån. Ett annat ökat behov skulle kunna vara elektriskt drivna jordbruksmaskiner för att förbättra produktiviteten och därigenom stimulera den ekonomiska tillväxten i byn.
174

Swarm grids - Innovation in rural electrification

Hollberg, Philipp January 2015 (has links)
Access to clean and affordable energy is a prerequisite for human development. In order to achieve access to sustainable energy for all innovation in rural electrification is needed. Decentralized renewable energy technologies in form of Solar Home Systems and Mini-grids possess the potential of electrifying a large number of rural households which cannot be connected to the national grid with local available energy sources. However, the deployment of Mini-grids is facing barriers such as a lack of private investments. By building on already existing SHSs swarm grids can enable households to trade electricity and use their excess electricity to supply additional loads. Swarm grids as an evolutionary bottom-up approach to electrification can overcome some of the obstacles regular Mini-grids face and play a vital role in improving electricity access. As part of this thesis a model has been developed which allows for simulating the electricity flow including line losses in swarm grids of any size on an hourly basis. The model facilitates the gaining of a better understanding for the impact global parameters (e.g. distance between households) have on the feasibility of swarm grids. A field trip to Bangladesh has been undertaken in order to obtain input data for simulating different cases in the model created. The simulations performed indicate that in a swarm grid the generated excess energy of SHSs which so far is wasted can supply the demand of households without SHS as well as commercial loads such as irrigation pumps. Overall the results point towards swarm grids being an innovation with the potential of improving rural electricity access by building on existing infrastructure.
175

Evaluating the Role of Energy Policy for Electrification in Ethiopia

Abdulrahman, Akram January 2021 (has links)
Access to electricity is a scarcity throughout sub-Saharan African countries. The region currently has the lowestrate of energy access in the world and a total of 13 countries have an electrification rate of 25%. Comprehensiveenergy security is regarded as essential to obtaining sustainable and economic development in which access toaffordable and clean energy is part of the Sustainable Development Goals of the United Nations Agenda 2030.A country in the region that has had some sporadic success with electrification and unique developments withrenewable energy, is Ethiopia. Despite the significant overall increase of access to electricity over the past twodecades, the country still has an electrification rate that barely covers half of the population. An aspect that isviewed to have an impact on increased electrification and successful transitioning of deploying renewableenergy, is the use and presence of strong policies. Several researchers and scholars have explored the effect thatpolicy has on increased electrification and how they are useful for promoting renewable energy. This researchaims to investigate the role of policy for electrification via renewables in Ethiopia. The objective of the thesisis to explore sustainable development in terms of energy development, how climate change and economicdevelopment is tackled, and what specific influences shape the energy outlook of Ethiopia. A case study wasconducted which combined two different methods; content analysis of policy documents and semi-structuredinterviews with experts from various fields in which the data was triangulated in order to gain valuableperspectives and insights. The findings showcase that policy developments do seem to have an influence onincreased electrification and sustainable energy transitioning to some extent, with other factors also playing arole. Thus, this research will contribute to how sustainable development can be understood from the context ofenergy policy of a global south nation and provide insights which can further be elaborated on how policies canbe utilized for successful energy developments in other countries in the region.
176

Mechanisms of Contact Electrification at Aluminum-Polytetrafluoroethylene and Polypropylene-Water

Nauruzbayeva, Jamilya 04 1900 (has links)
Contact electrification refers to the transfer of electrical charges between two surfaces, similar and dissimilar, as they are brought into contact and separated; this phenomenon is also known as static electrification or triboelectrification. For example, everyone has experienced weak electrical shocks from metal doorknobs, wool and synthetic clothing on dry days. While contact electrification might appear insignificant, it plays a key role in numerous natural and industrial processes, including atmospheric lightning, accumulation of dust on solar panels, charging of liquids during pipetting and flow in the tubes, and fire hazards in granular media. Contact electrification at metal-metal interfaces is well understood in terms of transfer of electrons, but a comprehensive understanding of contact electrification at interfaces of electrical insulators, such as air, water, polytetrafluoroethylene (PTFE), polypropylene remains incomplete. In fact, a variety of mechanisms responsible for transfer of electrical charges during mechanical rubbing, slipping, sliding, or flow at interfaces have been proposed via: electrons, ions, protons, hydroxide ions from water, specific orientation of dipoles, mechanoradicals, cryptoelectrons, and transfer of material. We have noticed that the extent of contact electrification of solids in water is influenced by surface free energies, mobile ions, surface roughness, duration of contact, sliding speeds, and relative humidity. Herein, we present results of our experimental investigation of contact electrification at the following interfaces: (i) PTFE-aluminum in air and (ii) polypropylene-water interfaces. To identify the underlying mechanism, we started with various hypotheses and exploited a variety of experimental techniques to falsify most of them until we got an answer; our techniques included high-voltage power supply (0-10,000 V), Faraday cages, Kelvin probe force microscopy, electrodeposition, X-ray photoelectron spectroscopy, energy-dispersive spectroscopy, optical microscopy, a contact angle cell, and high-speed imaging. We concluded that contact electrification at the PTFE-aluminum interface was driven by electrons transferred from aluminum to PTFE. In contrast, contact electrification at the polypropylene-water interface was driven by the specific adsorption of OH- ions onto polypropylene. These insights should be helpful in designing applications of polymers where electrical charging could have influence, or applications that could be based on electrical charging at such interfaces, such as triboelectric generator.
177

Study of technological, economical and social aspects to energise off-grid regions through distributed generation in developing countries

Shukla, Anand 15 May 2007 (has links)
In rural areas, access to electricity is required for better living standard, enhance income options and reduce population migration. In last decades, steady progress has been made but the status of electrification significantly varies across countries. In developing countries, about 1.6 billion people live without electricity and another 2 billion have access but to an unreliable extent. Large population also live in remote areas where extension of grid is not feasible, where people continuing to live under distress conditions. International projections reveal that number of un-electrified people will remain same by the year 2030 if similar pace of electrification is continued in future.From this perspective, the study describes what bigger countries such as India, China and Brazil are doing and where rural electrification stands in priority in a poor country like Ethiopia. Is off-grid technologies show an option for such remote locations" The two case studies of Vietnam and South Africa reveal that work carried out through external support in the absence of national policies. As a result, people have experienced the benefits of technologies but unable to retain them in long term. Electricity has given various advantages but poor affordability of the people hinders the acceptance of technologies in rural areas.The study shows the need of a framework to achieve the long-term support for rural electrification. A framework that could direct the national priorities, understands social, economic and environmental aspects of off-grid technologies, identify key areas to be strengthen, allocates the roles and responsibilities at different working levels, maintains a consistent flow of adequate finance, pursue regular monitoring process and incorporate the monitoring results, or, critical success factors into the national policies to make them more effective. Both macro- as well as micro- level approaches have been suggested in this study.
178

The Challenge of Providing Sufficient Grid Capacity for Electrification to Be a Key Factor in Achieving Climate Neutrality Until 2045 : A national and regional demand analysis investigating the future electricity demand and the grid operators' perspectives on large-scale electrification in Sweden

Ackebjer Turesson, Hampus, Werneskog, Jesper January 2020 (has links)
The purpose of the thesis is to contribute to grid planning and public debate about how the electric power system can cope with electrification and decarbonisation. The thesis is based on the assumption that Sweden, in accordance with the climate goals, will achieve climate neutrality by 2045. Based on a literature review, an analysis is made of how different scenarios predict the future national electricity demand up until 2045 and identifies the underlying drivers for changes in electricity demand. A more detailed analysis based on results from a literature review and interviews with industry representatives is made for four chosen regions, Norrbotten, Västra Götaland, Stockholm and Skåne. For each region, estimates are made of how high the electrification potential is in the industrial, transport, residential and service sectors. The prerequisites for the electricity grid to handle the identified electrification potential, in terms of grid capacity, have been analysed in order to highlight what challenges there are for large-scale electrification to be a key factor in achieving the climate goals. The general belief in the studied scenarios is that the national electricity demand will increase until 2045. The investigated scenarios predict increases resulting in an annual national electricity demand of up to 207 TWh in 2045, corresponding to an increase of almost 60 %. The most significant increases are due to decarbonisation in the industry and transport sector. The regional analysis shows significant electrification potentials in the investigated regions. A few industries stand out with dramatic increases, Borealis AB in Västra Götaland shows an electrification potential of 8 TWh and 1 000 MW and SSAB in Norrbotten shows an electrification potential of 9 TWh and 900 MW. Significant electrification potentials in the transport, residential and service sectors have been identified in metropolitan areas, i.e. in the region of Stockholm, Västra Götaland and Skåne. The grid analysis shows that it will be challenging to increase grid capacity at sufficient speed. It is concluded that there is currently insufficient grid capacity to meet large-scale electrification, and that the grids need to be reinforced. However, the concession process for grid reinforcements is considered too slow to meet the demands that arise, primarily in the industry sector. Three ways to address this challenge have been identified: -          If the permission process for electricity grid expansion does not change and the industry is to choose the electrification route, this needs to be decided before 2030 in order for reinforcements in the electricity grid to be ensured before 2045. -          Speed up the permit process to allow shorter lead times for power grid expansions. -          The industry choose another route for decarbonisation than electrification. The overall conclusion is that new approaches for expanding the electricity grid will be required if large-scale electrification is to be a key factor in achieving the climate goals in 2045.
179

Energy Management of Dynamic Wireless Power Transfer Systems for Electric Vehicle Applications

Azad, Ahmed N. 01 December 2019 (has links)
Wireless power transfer is a method of transferring electric power from a transmitter to a receiver without requiring any physical connection between the two. Dynamic Wireless Power Transfer (DWPT) entails having the transmitters buried under the roadway and the receiver unit being installed on the Electric Vehicle (EV). In this method, EVs are charged while driving over the transmitters as they receive bursts of electric energy at the time of significant alignment between transmitters and receivers. Compared to the stationary charging method which involves parking the EV for long hours for a full charge, the dynamic charging method (i.e., DWPT) offers convenience as the vehicle gets charged while driving. It also facilitates extended driving range of EVs. Despite offering these advantages, DWPT causes a few significant issues. DWPT charging results in a transient power profile both at grid side and EV side, which not only hampers grid-side regulation but also affects EV-battery longevity. To address these two issues, both grid-side and EV-side energy management are needed to be employed to protect the grid and the vehicle from sudden exposure to harmful power transients. In this dissertation, the grid-side and EV-side energy management methods have been investigated. Firstly, a detection system to safely detect the vehicle on charging lane is proposed. This detection system is used to facilitate safe and efficient operation of DWPT chargers on EV roadways. Secondly, A novel DWPT system is proposed, which reduces the grid-side power transients with minimal additional hardware requirements. Finally, an EV-side energy management system is proposed which reduces the exposure of EV batteries to pulsating DPWT-power, thereby helping batteries to last longer.
180

Watt’s the big deal? : European Green Deal’s impact onelectrification research in the automobileindustry

Ryttegård, Saga, Schulz, Lewin January 2023 (has links)
The attitude towards sustainability has vastly changed in the last few years.The European Green Deal(EGD) is a European law package that addresses the climate crisis and aims to transform businesseswithin the European Union towards more sustainable models. The automobile industry especially is atarget of transformation with the decarbonization efforts mandated by the Green Deal. As such, onewould expect a drastic change of how business is done around the time the Green Deal was passedand the years following it. This thesis has analyzed the annual reports of four large automobile firmsusing qualitative coding within the European Union from 2018 to 2022 in order to evaluate how thelaw package has influenced electrification research. This thesis used theoretical concepts such asinstitutional theory, theories about uncertainty and theories about innovation to analyze the results.Results indicated that while the Green Deal’s ambitions and targets are being set into motion, firmsmight not consider it as their guiding hand while moving towards sustainability. While theirconfidence levels in the EGD vary, there is plenty of opportunity for the EU to increase innovation atthis critical point in time through partnerships and infrastructural support.

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