Dissertations / Theses on the topic 'GRID/OFF-GRID'
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Dahlbom, Roland. "Off grid eller energiplushus. : Är det möjligt att gå off grid?" Thesis, Mittuniversitetet, Institutionen för kemiteknik, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:miun:diva-39322.
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Målet med den här undersökningen har varit att se om fastigheten Orkestern 1 går att koppla off-grid och om det är ekonomiskt försvarbart eller om en on-grid lösning är bättre. Förutsättningarna är goda med ett stort tak med plats för solpaneler i öst-västlig riktning och en årsmedelvind på 4 m/s. Då huset är nybyggt och välisolerat är även energiförbrukning låg. För att kunna beräkna hur mycket energi som ska produceras i form av värme och el med hjälp av solceller, vindkraftverk, pelletskamin och dieselverk upprättas en energibalans och energifördelning med hjälp av transmission och ventilationsberäkningar. Lagring av energi görs i form av pellets, batteri och biodiesel. Simuleringsprogrammet för solceller Polysun används för att beräkna produktion av solel över varje månad på året. Diagram upprättas över året indelat i månader där det framgår hur stort energibehovet är och visar hur stor del varje energiproducent har varje månad. En pay-off kalkyl görs för att se om det är ekonomiskt lönsamt och för att kunna jämföra mellan två olika off-grid system. Pay-off kalkylen används också för att jämföra mellan off-grid och on-grid system. Resultatet landar i att on-grid systemet är ekonomiskt hållbart medan off-grid systemet inte är det men är ändå fullt genomförbart.The main target of this examination has been to see if the real estate Orkestern 1 has the possibility to go off-grid and if it is economical defendable or if on-grid solution is a better way to go. The prerequisites are good with a large roof to place solar panels to the east and west, a yearly average windspeed at 4 m/s and a low energy consumption because the house is new built and well insulated. To calculate how much energy that must be produced in form of heat and electricity with solar cells, windmills, pellet stove and diesel generator an energy balance and an energy distribution will be prepared with help of calculations of transmission and ventilation loses. Storage of energy will be done in form of pellets, battery and biodiesel. The simulation program for solar panels Polysun is used to calculate the produced solar energy for each month on the year. Diagram is prepared for each month to see the need of energy and how much every energy producer is delivering. A straight pay-off calculation is done to see if there are any economic benefits and to compare between off-grid and on-grid systems. The result will be that on-grid system is better economical but still the off-grid system is doable.
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Stenermark, Johan. "COGL : Compact Off-Grid Living." Thesis, Mälardalens högskola, Akademin för innovation, design och teknik, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-50955.
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This project was done at Mälardalens University at the school of Innovation, Design & Engineering. The project is a thesis of 15hp for the program in innovation and product design, the project began in spring 2018 and was completed in the summer 2020, its focus on design and construction with regards to, among other things, the environment. The work covers a project development process where a self-sufficient accommodation inside of a shipping container is designed and constructed with a goal to end in an overall construction. The project is not for a company but comes from an individual idea where the result is presented in the form of a report and a entailed CAD-assembly of the accommodations different parts. The content and construction of the accommodation is produced with the first phases of the project development processes, information is collected, concepts are created, and solutions are designed. These phases are iterated so that the result generates a as solid base as possible. Through the work process, the environment and cost are of great importance. The result of the project was an accommodation, which for a week is self-sufficient in electricity and water usage for one person. The resulting accommodation includes; bathroom with shower and toilet, kitchen with sink and gas-hob, electricity and water central where electricity and water is stored and processed, and bed, table and storage. All these functions are located on a floor area of 9,3 m2. The accommodation is constructed in CAD, where its different systems have been developed and designed at a basic level for easy further work at a detail level. The accommodation is not fully designed/constructed but provides an overall plan on how this type of accommodation can be created and its approximate cost, 95´000:-. The solutions and costs may differ in the realization of the accommodation as certain delimitations were made so that this work could be carried out. The project har several development directions where the focus can be within; detail development, selfsufficient living, or temporary conventional accommodation.Detta examensarbete gjordes på Mälardalens Högskola på akademin för Innovation, Design Teknik. Arbetet är ett examensarbete på 15hp för programmet i innovation och produktdesign, arbetet påbörjades våren 2018 och slutfördes sommaren 2020, det är inriktat på design och konstruktion med avseende på bland annat miljö. Arbetet består av en produktutvecklingsprocess där ett självförsörjande boende inuti en container designas och konstrueras med avseende att sluta i en övergriplig konstruktion. Arbetet sker inte mot ett företag utan kommer från en individuell idé där resultatet presenteras i form av en rapport och en medförande CAD-sammanställning som utgör boendets olika delar. Boendets innehåll och konstruktion har tagitsfram med hjälp av produktutvecklingsprocessens första faser, insamlad information leder till koncept som leder till lösningar. Dessa faser itereras för att resultatet ska generera en så ordentlig bas som möjligt. Genom arbetets gång har miljö och kostnad stor vikt. Resultatet blev ett boende vilket under en veckas period är självförsörjande av el och vatten för en person. Boendet inkluderar; badrum med dusch och toalett, kök med diskho och gasolplatta, el-och vatten-central där el och vatten förvaras och processas, och säng, bord och förvaring. Alla dessa funktioner ligger på en golvyta av 9,3 m2.Boendet är konstruerat i CAD där dess olika delsystem tagits fram och designats på grundnivå för enkelt vidarearbete av detaljnivå. Boendet är inte designat/konstruerat till fullo utan ger en övergriplig plan om hur ett boende av denna typ kan skapas och dess ungefärliga kostnad, 95 ́000:-. Boendets lösningaroch kostnader kan skilja sig vid förverkligandet av boendet då vissa avgränsningar gjordes för att detta arbete skulle kunna genomföras. Arbetet har flera potentiella utvecklingsriktningar där fokus kan ligga inom; detaljutveckling, självförsörjning, eller portabelt temporärt konventionell boende.
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Ongie, Gregory John. "Off-the-grid compressive imaging." Diss., University of Iowa, 2016. https://ir.uiowa.edu/etd/2126.
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In many practical imaging scenarios, including computed tomography and magnetic resonance imaging (MRI), the goal is to reconstruct an image from few of its Fourier domain samples. Many state-of-the-art reconstruction techniques, such as total variation minimization, focus on discrete ‘on-the-grid” modelling of the problem both in spatial domain and Fourier domain. While such discrete-to-discrete models allow for fast algorithms, they can also result in sub-optimal sampling rates and reconstruction artifacts due to model mismatch. Instead, this thesis presents a framework for “off-the-grid”, i.e. continuous domain, recovery of piecewise smooth signals from an optimal number of Fourier samples. The main idea is to model the edge set of the image as the level-set curve of a continuous domain band-limited function. Sampling guarantees can be derived for this framework by investigating the algebraic geometry of these curves. This model is put into a robust and efficient optimization framework by posing signal recovery entirely in Fourier domain as a structured low-rank (SLR) matrix completion problem. An efficient algorithm for this problem is derived, which is an order of magnitude faster than previous approaches for SLR matrix completion. This SLR approach based on off-the-grid modeling shows significant improvement over standard discrete methods in the context of undersampled MRI reconstruction.
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Sjolte, Jonas. "Marine renewable energy conversion : Grid and off-grid modeling, design and operation." Doctoral thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for elkraftteknikk, 2014. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-26004.
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The global energy production from renewable sources is increasing, with high penetration of both wind and solar in key regions. Ocean Wave Energy is projected to contribute with an increasing share of the future power supply, and the focus of this work is to investigate the requirements for connecting wave energy to the power grid, in context of the Fred. Olsen (FO) Wave Energy Project. Most Wave Energy Converters (WECs) produce highly distorted power due to the reciprocal motion induced by the ocean waves. Some WEC systems have integrated energy storage that overcomes this limitation, but adds significant expenses. As an alternative approach, this work investigates direct power export that relies on aggregate smoothing among several WECs. By optimizing the position of the WEC devices with respect to the incoming waves, fluctuations may be mutually canceled out between the devices. FO has closely monitored the global development within wave energy for about two decades, and has worked actively on developing WECs since 2002. The latest WEC system, named Lifesaver, has been in operation since April 2012 and is the basis of this thesis work. The Lifesaver system is described in detail, and comprehensive data on operational performance is presented. The major cost driver for grid integration is the peak to average power ratio, which can be as high as 20 in the early power conversion stages. Thus, it is crucial to improve the power quality early in the conversion chain so that the downstream power system is efficiently utilized. The simulations undertaken in this work indicate that a high quality power output can be achieved at the farm level, but that significant oversize factors will be required in the intermediate power systems within the farm. Cost-benefit analysis of the system show that a grid connected system at the current technology level will return marginal profitability. Therefore, several alternative approaches are investigated that could serve as a bridge towards future large scale systems. This includes autonomous systems that could supply power to remote ocean based units such as measurement and surveillance buoys, aquaculture facilities and support systems for the off-shore oil and gas industry. In general, the findings show that the WEC system is well suited for grid integration, although it becomes clear that significant development remains before wave energy can become an important supplement in the energy mix. Moreover, there seems to be a market for autonomous systems that is economically viable at the current technology level that could allow for immediate deployment of commercial systems.
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Bramberg, Gustav. "Framtida energiförsörjning till off-grid basstationer." Thesis, KTH, Industriell ekologi, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-121767.
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Telekombranschen har de senaste decennierna upplevt en stark tillväxt, framförallt i urbana områden och västvärlden. Nu när denna tillväxt även sker i utvecklingsländer och dess landsbygd, söks det efter nya sätt att försörja basstationer som ej är kopplade till elnätet med energi. Syftet med detta examensarbete är att studera och analysera framtida hållbara energilösningar för basstationer inom telekombranschen. Detta görs genom att kartlägga alternativ, analysera vilka hinder och möjligheter som finns samt undersöka vilka kompetenser som krävs för en vidare utveckling. Arbetet har framförallt baserats på intervjuer av aktörer i telekombranschen samt litteraturstudier. Studien visar att de tekniker som i framtiden har störst potential att ersätta dieselgeneratorerna idag är solceller samt småskalig vindkraft. För att denna utveckling skall ske krävs det innovationer och nya sätt att implementera energisystem med basstationer. I framtiden kommer det även finnas ett stort behov av projektering och modeller för att dimensionera samt optimera basstationers energisystem.In recent decades, the telecom industry has experienced a rapid growth in urban areas and the western world. This growth is now spreading towards developing countries and their rural areas, where proper energy grids may be lacking. In order to cope with insufficient energy infrastructure and improve their services in rural areas, the telecom industry is now looking to develop better off-grid telecom base stations. The purpose of this thesis is to study and analyse future sustainable energy solutions for off grid base stations in the telecom industry. This is purpose will be met by mapping possible alternatives and analysing what advantages and disadvantages these alternatives have, as well as investigating what competencies the industry needs. The work is foremost based on literature studies and interviews of stakeholders in the telecom industry. The study concludes that photovoltaic solar cells and small scale wind power are the two energy generating technologies that has the greatest potential of replacing the diesel generators that are now commonly used on off grid base stations. In order for this to happen, two important areas that the industry needs to focus on is innovation and new ways of implementing the energy systems with base stations. The demand of planning, dimensioning and designing the energy systems will increase in the near future as the renewable energies increases their market share.
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Skivington, Graeme Ross. "Off grid applications for wind power." Thesis, University of Strathclyde, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.426299.
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Bally, Todd. "Off the grid eco-friendly industry /." This title; PDF viewer required. Home page for entire collection, 2009. http://archives.udmercy.edu:8080/dspace/handle/10429/9.
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Onyia, Chukwuebuka Louis. "Nanogrid For Renewable Off-Grid System." Thesis, Uppsala universitet, Institutionen för informationsteknologi, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-397052.
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Power grids utilize large central generating stations which entails the use of long transmission lines to deliver power to consumers. This approach poses some challenges such as line loses and carbon dioxide (CO2) emission into the environment from the burning of fossil fuels from such large generators. There is also little or no availability of electricity in the rural and isolated areas where the supply of power from the national grid may be considered uneconomical. Distributed generation proffers solutions to these challenges by generating power close to the point of consumption. A nanogrid is an important aspect of distributed generation in which electricity is generated for a single building. Nanogrids usually employ renewable sources of power such as solar and wind energy to generate electricity. Hence, reducing carbon dioxide emission. Also due to the versatility of nanogrids, people in the rural areas can generate their own electricity. However, the intermittent supply of power due to the variations of wind speed during the entire course of a day poses a major challenge in the use of nanogrids. This thesis focuses on the study of the interaction of the savonius wind turbine in an existing nanogrid with a particular load so as to have a better understanding of how the wind turbine parameters such as the wind speed and Tip Speed Ratio can affect the power generated from the turbine. This is achieved by modelling and measuring the power absorption of the savonius wind turbine operating in the nanogrid. From the results obtained in this project, it is glaring that the wind speed and Tip Speed Ratio of the wind turbine play a vital role in the total power harvested from the turbine. If the rotor blades spin too slowly, the wind will pass through the gap between the blades and no power will be generated. Whereas when the blades spin too fast, they act like a shield against the wind speed, creating turbulence in the air as they spin and so when the incoming blade arrives too fast, it hits the turbulent air created by the blade before it and thus, no power will also be generated in this situation. Therefore, it is of utmost importance to design the wind turbine with an optimal Tip Speed Ratio to obtain maximum power from the turbine and thus, improve the reliability and efficiency of the nanogrid technology.
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Chlebný, Radek. "Autonomní dům aneb život grid-off." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2013. http://www.nusl.cz/ntk/nusl-220159.
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This thesis deals with energy self-sufficiency focusing on the independence of the electric grid. Basic line emanating project form a concrete proposal for autonomous energy supply system. Emphasis is placed primarily on photovoltaic systems, electric energy accumulation and selection of individual components of such a system. Another important part of the thesis is also an economic evaluation of design variations. The thesis also deals with a market research, and thereof derived benefit assessment of each technology. The accompanying chapters are then devoted to the history of autonomous life style or classification of buildings according to their energy performance.
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Kellner, Philip. "Off-grid eller självförsörjande fjällby- en fallstudie." Thesis, KTH, Skolan för industriell teknik och management (ITM), 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-217338.
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Kanten, Bethany. "Power Monitoring Device for Off-Grid Solar." Thesis, Harvard University, 2015. http://nrs.harvard.edu/urn-3:HUL.InstRepos:14398556.
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Off-grid solar power systems are being used in rural, developing regions of the world to provide electricity to communities that previously didn’t have access. These systems are unable to communicate data about power generation and consumption to the organizations that install them. This information can be critical for the organization to ensure they are providing quality electricity, maintain the health of the components in their system, and evaluate the impact they are having in the community. I designed and built a device to monitor power at both the generation and AC or DC consumption sites. Once daily it sends the data to a website via text message where is it displayed to the installer. The device also stores the data locally on a microSD card. The final device abides by the key specifications set by the prior art of low cost and low power consumption. The device also addresses key challenges of off-grid monitoring including data transmission via text message, battery monitoring, reliability/ durability, and versatility with load site monitoring.
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Straka, Michal. "Využití fotovoltaických systémů v Off-grid aplikacích." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2012. http://www.nusl.cz/ntk/nusl-219396.
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This masters thesis deals with the use of off-grid photovoltaic systems. First we explain the problems associated with the power and energy potential of photovoltaic system components, design of photovoltaic systems for autonomous operation and the financial evaluation. The result of the masters thesis is to create an application used to design the island system in the whole output range (the smallest power systems to house systems application). The conclusion of the masters thesis is devoted to designing three type of projects from our application – a garden cottage, a family cottage and the house.
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Havránek, Miroslav. "Větrná elektrárna grid-off, princip, účinnost, návratnost." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2013. http://www.nusl.cz/ntk/nusl-220157.
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This Master´s thesis deals with problematics of wind powered generators and their use in off-grid systems. In its first chapters aspects of wind as a power source are analyzed. Further on the thesis focuses on individual components of the off-grid systems. Also designing procedures of these systems are presented in the paper. The key parts of the thesis are 3 off-grid wind power system designs, which can be used to power a family house, and their energetical and economical evaluation.
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Xu, Yang. "Analysis of on-grid and off-grid cost for rural electrification in developing countries." Thesis, KTH, Skolan för elektroteknik och datavetenskap (EECS), 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-247889.
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Electricity is a fundamental energy carrier for modern life and for economic prosperity. All kinds of equipment use electricity as their power source, including domestic and industrial applications. There is a trend to adopting more electricity-based equipment in all areas. The modern power infrastructures can sufficiently supply most cities and developed areas. However, certain rural areas are still unable to get access to electric power due to the inconvenient locations or less developed economy. This makes the living conditions in such areas extremely inconvenient and further hinders the economic development in those areas.Electrification for rural areas has been a critical task for some developing countries. To accomplish this task, the options are limited to build a stand-alone power system or construct a power transmission line for the chosen location. A stand-alone power system has commonly been based on fossil fuel, such as a diesel generator, with low capital cost compared to a long connection, but with significant running cost of fuel. Recent improvements of renewable sources and storage, and more efficient loads, have made renewable sources much more competitive than before for a stand-alone electricity supply. The choice between different renewable energies depends on the local natural resources. It is a more flexible way to providing the electricity and a more efficient and environmental-friendly way since the energy loss caused by transmission is eliminated. On the other hand, the grid connection option involves building a transmission line to connect the rural area to the national grid, which is a more traditional approach to provide power. The cost of this method depends on the relative distance between the rural area and the nation grid.The choice between the above two mentioned electrification options is the first step when considering providing power to the rural area. This thesis focuses on the electrification for rural areas and comparing the above two methods, finding out the break-even point. It is of current interest as the technology for both options is changing, and the break-even is also changing.In this thesis, a mathematical model for on-grid electrification is proposed and simulated on MATLAB. The off-grid option is simulated by HOMER. The results show how the LCOE of on-grid and off-grid electrification as well as the off-grid configuration are affected by different parameters like the distance to grid, load demand level, PV cost, WT cost, storage cost, the diesel price and so on. By comparing the results, the break-even point of two options is also presented.Elektricitet är den viktigaste energibäraren för det moderna livet och för ekonomiskt välstånd. Många typer av utrustning använder el som sin kraftkälla, i hushållet såväl som I industrin, och det finns en tendens att öka användning av el inom alla områden. Moderna elnät levererar till de flesta städer och utvecklade områden. Dock har vissa landsbygdsområden fortfarande inte elförsörjning, på grund av svårtillgängliga områden och mindre utvecklade ekonomier. Detta gör att levnadsförhållandena i sådana områden är lägre än om man hade haft tillgång till el, och ytterligare hindrar den ekonomiska utvecklingen i dessa områden.Elektrifiering för landsbygdsområden har varit en viktig uppgift för vissa utvecklingsländer. Två extrema fall är att bygga ett fristående lokalt kraftsystem, eller att bygga nya kraftledningar för att ansluta till ett befintligt elnät. Ett fristående kraftsystem har historiskt sett typiskt berott på fossila bränslen, till exempel med en dieselgenerator, vilket ger lägre kapitalkostnad än en lång ledning, fast med betydande driftskostnader för bränsle. De senaste förbättringarna av förnybara källor och lagring, samt effektivare laster, har gjort förnybara källor mycket mer konkurrenskraftiga än tidigare för en fristående elförsörjning.Valet mellan de två ovannämnda alternativen är det första steget när man elektrifierar ett landsbygdsområde. Denna uppsats fokuserar på elektrifiering för landsbygdsområden och jämför dessa två metoder. Det är av aktuellt intresse eftersom tekniken för båda alternativen är i förändring.I denna uppsats, en matematisk modell för on-grid elektrifiering är föreslås och simuleras på MATLAB. Alternativet off-grid simuleras av HOMER. Resultaten visar hur LCOE av on-grid och off-grid elektrifiering såväl som nätverkskonfigurationen påverkas av olika parametrar som avståndet till rutnätet, lastbehovsnivå, PV kostnad, WT kostnad, lagerkostnad, dieselpriset och så vidare. Genom att jämföra resultaten, jämnpunkten av två alternativ är också presenterad.
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Steel, Katherine Deaton. "Energy system development in Africa : the case of grid and off-grid power in Kenya." Thesis, Massachusetts Institute of Technology, 2008. http://hdl.handle.net/1721.1/43840.
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Thesis (Ph. D.)--Massachusetts Institute of Technology, Engineering Systems Division, 2008.Includes bibliographical references.
This research used a combination of a grounded theory approach and system dynamics to study the electric power system in Kenya and to model the feedback at work in the development of the system. The ethnographic study revealed the challenges faced by consumers in choosing between grid and off-grid power options. Examination of this challenge leads to the hypothesis that competition between the grid and off-grid markets is contributing to the low growth in power consumption and that there is the potential for off-grid to become the dominant option in the future. This theory guided the construction of a system dynamics model focusing on consumers' decision-making and their interaction with the operation of the system. I then used the model to explore the dynamics of the system through scenario testing. There were two key outcomes from the model. The first showed that given the parameters chosen in most cases there is a clearly dominant option, although it changes over time. This finding points to the second key outcome the model, which is that there are realistic scenarios under which off-grid generation will become the dominant supply source. This shift could be induced by either reduced overhead on photovoltaic panels or high fuel prices. The outcomes from this research have implications for future electricity planning in Kenya and elsewhere in Africa. In particular, there is a need to decouple the system from external prices or account for the extreme uncertainty in fuel prices. Given the potential shift to large-scale off grid power generation, energy planners also need to look at options for managing a decentralized power system architecture and consider how to build in options for future reintegration if a large-scale centralized generation source comes online.
(cont.) This research has both academic and applied contributions. On the academic side, it extends the range of engineering systems modeling to include qualitative factors found in an African environment. These factors include the addition of reliability and availability of the electric power grid and the biases in decision-making, which differ from those in industrialized countries. While the model clearly has direct application in Kenya, it was designed with flexibility to be expanded to include other countries and regions and could be a useful tool for understanding policy trade-offs in African electrification planning.
by Katherine Deaton Steel.
Ph.D.
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Boyer, Kyle, Laura Brubaker, Kyle Everly, RIchard Herriman, Paul Houston, Sean Ruckle, Rory Scobie, and Ian Ulanday. "AN EXPANDED COMMUNICATIONS SYSTEM FOR OFF-GRID TELEMETRY." International Foundation for Telemetering, 2017. http://hdl.handle.net/10150/626973.
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The drivers of the University of Arizona Baja racing team must be intensely focused on tackling the jumps, boulders, mud bogs, and other challenges in the four-hour endurance race. These obstacles are just as demanding on the vehicle as the driver, so the pit crew needs effective ways of detecting problems within the vehicle before serious damage occurs. Our solution is a wide range, AES encrypted, Wi-Fi communications system that supports full IP protocol and live video feed, allowing our telemetry data to be accessed through a smartphone via a web interface. To provide a wide range of communication options, our system supports VOX and push-to-talk audio compatible with third-party radios, and has an on-board HDMI screen for text-based communications. Finally, our system is backwards compatible with prior generations to make repairs and replacements easy.
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Alam, Majbaul. "Decentralized renewable hybrid mini-grid based electrification of rural and remote off-grid areas of Bangladesh." Thesis, De Montfort University, 2017. http://hdl.handle.net/2086/14535.
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Like many other developing nations Bangladesh has a very poor electrification rate especially in the rural areas. Millions of people here are excluded from the benefit of globalization because of no access to necessary electricity supply. This research work proposes decentralized renewable hybrid mini-grids as a potential approach for off-grid rural and remote area electrification in Bangladesh. Based on the available renewable resources an area specific resource map has been developed. The characteristics of the bottom of the economic pyramid market including customers’ attitude to switch from liquid fuel to mini-grid based electricity supply, expected load demand and their willingness to pay have been explored through a field study. Different combinations of hybrid systems have been designed and optimized using the HOMER micro-grid design software to cover the whole country. Results suggest that serving the required load over wider hours rather than having the same load concentrated in a short span of time can achieve better hybrid system performance. Initial capital subsidy of 40 percent along with 5 percent interest on loan has been applied in accordance with the renewable energy policy of Bangladesh government. Proposed optimized rice husk-diesel hybrid system in Rangpur, micro hydro-PV system in Rangamati, wind-PV system in Chakaria and PV-diesel system in coastal areas can produce electricity for USD 0.172/kWh, 0.291/kWh, 0.217/kWh and 0.316/kWh respectively while serving loads for 12 to 18 hours a day. Field data analysed by applying the dichotomous choice contingent valuation method revealed that customers are willing to pay maximum of USD 0.43/kWh. The value difference between the cost of electricity generation and the customers’ willingness to pay creates the opportunity to attract the private investors. Suitable business delivery models have been identified and explained for successful mini-grid business by private investment. Optimum hybrid systems have been standardized for replication and a sustainable business model has been suggested for scaling up this electrification approach.
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Hu, Huafen. "Risk-conscious design of off-grid solar energy houses." Diss., Atlanta, Ga. : Georgia Institute of Technology, 2009. http://hdl.handle.net/1853/31814.
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Thesis (Ph.D)--Architecture, Georgia Institute of Technology, 2010.Committee Chair: Godfried Augenbroe; Committee Member: Ellis Johnson; Committee Member: Pieter De Wilde; Committee Member: Ruchi Choudhary; Committee Member: Russell Gentry. Part of the SMARTech Electronic Thesis and Dissertation Collection.
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El, Zein Musadag. "Off-grid Wind Power Systems: Planning and Decision Making." Thesis, Uppsala universitet, Institutionen för geovetenskaper, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-396057.
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There are definitely many reasons for choosing off-grid wind power systems. Few key ones involve the positive enhancement of societies, economies and natural environments. From a project developers’ perspective these systems provide a large potential market, which can cover a wide range of applications with relatively reasonable costs. In spite of this, many challenges may interfere with the diffusion and the success of such systems. In the report we discuss the various factors affecting the implementation of off-grid wind power systems and demonstrate some of the challenges project developers may be facing during the planning stage. Some of these include the acceptance of stakeholders (local inhabitants in particular) and the securing of the financing of the projects. Another noted challenge lying outside the control of project developers was found to be the absence of encouraging policies and incentives. As a conclusion the thesis provides a set of self-interpreted recommendations along with a flow chart. The concluded summary indicates some key factors that project developers should be aware of and careful when dealing with, these which include: The choice of the site, verification of projects’ economics along with the securing of a convenient finance. The recommendations also point out the great advantage in having local developers as these tend to be more capable in building relations with the local citizens and politicians.
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Lim, Pei Yi. "Power management strategies for off-grid hybrid power systems." Thesis, Curtin University, 2011. http://hdl.handle.net/20.500.11937/2503.
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At present, there are still a large number of people living in isolated areas, particularly in developing countries, who have no immediate access to the main electricity grid. Most of the energy demands of these remote communities are met by diesel-operated power systems, which are relatively affordable and available. With the ever increasing awareness of climate change, many local authorities have taken initiatives to reduce the carbon footprint of certain energy sectors. In some rural applications, diesel generator power systems are augmented by single or multiple renewable energy supply units to form an off-grid hybrid power system.Generally, the majority of off-grid hybrid power systems include a massive battery bank to store excess renewable energy to supply the user load demand during the period when renewable energy is deficient. In the charging and discharging processes, energy losses may occur due to the inefficiency of the charger and the battery cells. Also, inclusion of an energy storage element into a hybrid power system incurs additional investment costs and involves recycling issues. Therefore, it is necessary to minimise the size of storage, whenever possible, and operate the system under an appropriate power management strategy to ensure efficient system operation.The chosen power management strategy impacts long-term performance of a system as well as components’ longevity. The research presented in this thesis describes the development of an advanced power management concept for the operation of a photovoltaic-variable speed diesel generator hybrid power system.A general introduction regarding the research background to hybrid power system applications and fundamentals of solar energy is presented. A component sizing and control program is developed to facilitate hybrid power system design. Then, various off-grid power system configurations are further discussed with emphasis on the system performances and economic aspects.A prediction technique, namely the Hourly-based Prediction Model for solar irradiance and load demand forecasts is discussed. Forecast algorithms for the hourly solar irradiance and load demand predictions are presented. The proposed prediction models are implemented in the power management strategy for the off-grid photovoltaic-variable speed diesel generator hybrid power system. Assessments of the prediction models through comprehensive analyses of statistical measures are presented.HOMER simulation software has been adopted for time series generation and economic analyses for several off-grid power system configurations. Also, the HOMER simulation results for electrical aspects are used as a benchmark to evaluate the component models developed in this thesis. Due to the fact that HOMER offers limited choices of power management strategy and users do not have access to modify the control algorithms, it is impossible to determine the performance of a system under advanced power management strategy. Therefore, analytical performance models of system components have been developed using the MATLAB/Simulink software to allow the implementation of the proposed power management strategy.The concepts and flow charts of the predictive power management strategy are described. This power management strategy consists of predictive and adaptive dispatch. The time step of the predictive dispatch is fixed to one hour while the time step of the adaptive dispatch is one minute. Operation of the additional generator capacity of the hybrid power system is based on the predicted net load. The adaptive dispatch supports the predictive dispatch to handle fluctuations of net load that occur in between prediction intervals.Simulation results of the performance of hybrid power systems using different types of diesel generator and power management strategies are presented. Particular emphasis is on the comparisons of the system performances using non-predictive and predictive power management strategies. These simulations allow quantitative assessment of the system performances in terms of electrical output, fuel consumption and carbon dioxide emission.Last but not least, the entire research is summarised and concluded with suggestions for future research. In short, the photovoltaic-variable speed diesel generator hybrid power system topology and the proposed power management strategy offer an alternative to the off-grid hybrid power system design, with the aims of overcoming the complex technical issues associated with energy storage and of contributing to market extension of hybrid power systems, particularly in remote locations where financial and technical issues are the major concerns.
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MAROCCO, PAOLO. "Hydrogen-based energy storage systems for off-grid locations." Doctoral thesis, Politecnico di Torino, 2021. http://hdl.handle.net/11583/2945185.
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Aslan, Murad. "Implementering av solceller vid busshållplats." Thesis, KTH, Hållbar produktionsutveckling (ML), 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-298373.
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Idag är människor i behov av Wi-Fi, eluttag samt belysning och samtidigt är kollektivtrafiken en stor del av människors vardag. Syftet med arbetet är att undersöka huruvida en implementering av solceller kan gynna samhället utifrån ekonomiska, ekologiska och sociala perspektiv. Studien beskriver även hur prisskillnaden mellan On-Grid och Off-Grid kan variera på grund av komponenter som används i implementeringen. I genomförandet undersöks energibehovet för Wi–Fi, LED-belysning och eluttag och detta har lett till att batteristorleken för systemet är 150 Ah. Däremot har Sverige få soldagar vilket leder till att antal mörka nätter approximeras till två och batteristorleken fördubblas därför till 300 Ah. Resultatet uppvisar att anslutande av elnät till busshållplatsen betingar ett pris av 100 000 kr men att implementera Off-Grid system på busshållplatsen kostar 23 653 kr för huvudkomponenter exklusive pris av montering, säkring och kablar. Genom att implementera solceller på On-Grid systemet kan elkostnader för bolaget minskas och återbetalningstiden förkortas. Studien kom fram till att två paneler av Midsummer BOLD med 195 Wp kommer täcka systemets behov. Dessa paneler är svensk tillverkad från 100% förnyelsebar el och har lågt koldioxidutsläpp med runt 90% lägre än traditionella solceller.Today, people need Wi-Fi, electrical outlets, and lighting, and at the same time public transport is a large part of people's everyday lives. The purpose of the work is to investigate whether the implementation of solar cells can benefit society from an economic, ecological, and social perspective. The study also describes how the price difference between On-Grid and Off-Grid can vary due to components used in the implementation. The implementation examines the energy needs for Wi-Fi, LED lighting and electrical outlets and this has led to the battery size for the system being 150 Ah. On the other hand, Sweden has few sunny days, which leads to the number of dark nights being approximated to two and the battery size therefore doubling to 300 Ah. The results show that connection of the electricity network to the bus stop requires a price of SEK 100,000, but implementing Off-Grid systems at the bus stop costs SEK 23,653 for main components excluding the price of assembly, fuse, and cables. By implementing solar cells on the On-Grid system, electricity costs for the company can be reduced and the repayment period shortened. The study concluded that two panels of Midsummer BOLD with 195 Wp will cover the system's needs. These panels are Swedish made from 100% renewable electricity and have low carbon dioxide emissions with around 90% lower than traditional solar cells.
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Kuehn, Bernhard. "Off-grid hus : En simuleringsmodell för hus utan koppling mot elnätet." Thesis, Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-33373.
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Den Europeiska unionen har sina medlemsländer genom direktivet Energy Performance of Buildings Directive (EPBD) gett i uppdrag att minska energiåtgången för byggnader. Detta ingår i satsningen för att minska klimatpåverkan i hela EU. Nybyggda hus innebär bäst förutsättningar för att minska energiförbrukningen genom att den senaste tekniken kan utnyttjas ihop med utformning enligt de nyaste forskningsrönen. Syftet med det här arbetet är att undersöka om det är möjligt att bygga ett hus som är självförsörjande på el i Sverige genom att använda beprövad teknik. Undersökningen görs genom att bygga en datormodell av ett hus i Simulink för att beräkna energibehov under januari 2010 till december 2013. Huset är 160 m2 stort och står i Karlstad, Värmland. Den använda tekniken i huset är omfattande. De viktigaste komponenterna är en ackumulatortank på 9,3 m3, litium-jon batteri på 58 kWh vid 48 volt, ett vindkraftverk på 2 kWp, solceller på 58 m2och solfångare på 46 m2. Modellhuset liknar i sina egenskaper ett hus som har byggts i Tyskland och jämförs också mot detta avseende energiförbrukning och kostnader. För att kunna bedöma ekonomin jämförs modellhuset även med fem energieffektiva småhus från olika svenska hustillverkare. Modellen använder sig av mätdata som Sveriges meteorologiska och hydrologiska institut (SMHI) ställer allmänheten till förfogande. Data finns för varje timme under beräkningsperioden. Beräkningarna visar att 100 % självförsörjningsgrad på el är möjligt med den valda tekniska utrustningen genom att begränsa elanvändningen till ungefär 2 000 kWh/år. Värmeförsörjning görs med hjälp av solfångarna och ackumulatortanken. Självförsörjningsgraden på solvärme visar sig hamna omkring 58 % av värmebehovet. Den resterande värmen kommer från 4,6 m3 stjälpt björkved som eldas i en vattenmantlad vedpanna och motsvarar ungefär 5 400 kWh. Denna mängd ved kostar i dagsläget mindre än 3 000 kr/år. Datormodellhuset använder sig av mycket teknik vilket medför att priset ligger på ungefär 3,5 miljoner kr. Ett, i storlek och energibehov, jämförbart småhus koster i snitt 3,1 miljoner kr. Ett sådant småhus är dock inte självförsörjande på el. När man bygger ett hus som ligger långt från närmaste elanslutningspunkt behöver även kostnaden för anslutningsarbete beaktas. Ligger den närmaste anslutningspunkt 1 800 meter eller mer från den tänkta byggplatsen blir enbart kostnaderna för att ansluta huset till elnätet över 313 000 kr. Husbyggaren som vill bli oberoende av tillgängligheten av elnätet eller planerar att bygga ett hus som ligger långt ifrån en anslutningspunkt till elnätet har med resultatet från undersökningen ett verktyg för att ta fram planer för sitt bygge. Den undersökta husmodellen sänker de framtida kostnaderna för att driva huset och håller arbetsinsatsen nere för att förse huset med värme och varmvatten.The European Union has through the Directive Energy Performance of Buildings Directive (EPBD) given a mandate to its members to reduce energy consumption of buildings. This is part of the effort to reduce the carbon footprint across Europe. New houses have the best conditions to reduce their energy consumption by utilizing the latest technologies. This work examines whether it is possible to build a house that is self-sufficient in electricity in Sweden using proven technology. The survey is done by building a computer aided model of a house in Simulink to calculate energy requirements during January 2010 December 2013. The modelhouse is 160 m2 and use climatedata from Karlstad, Värmland. The calculations show that a self-sufficiency rate of 100 % of electricity is possible with the selected technical equipment by limiting the power consumption to 2 000 kWh per year. Heat supply is done by using solar collectors and a storage tank. Self-sufficiency for the heating is up to 58 %, wooden heating supplies the rest.
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Mordenti, Nicola. "Analisi e ottimizzazione di sistemi off-grid per l'elettrificazione rurale." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2019.
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Nel 2015 i 193 membri delle Nazioni Unite si sono fissati l'obiettivo entro il 2030 di assicurare l’accesso all’elettricità a chiunque.
E' un obiettivo molto ambizioso se si considera che circa 1.3 miliardi di persone al momento non hanno accesso all’elettricità
Il processo di elettrificazione deve riguardare specialmente le zone rurali.
I sistemi off-grid rappresentano una possibile soluzione. I Solar Home System (SHS) permettono tramite un piccolo pannello fotovoltaico di fornire energia a determinati carichi.
Un ruolo fondamentale è svolto dalle batterie quando il fotovoltaico non riesce a fornire sufficiente potenza al fine di alimentare il carico.
Il problema finanziario è uno dei maggiori ostacoli visto i salari molto bassi delle popolazioni beneficiarie della tecnologia.
Si tratteranno nella seconda parte vari casi studio. I primi riguardanti il Perù, nel quale l’opera di elettrificazione riguarda soprattutto le zone andine e la foresta amazzonica.
Seguiranno casi studio relativi all’ottimizzazione del sistema stesso con un confronto tra varie tipologie di batterie e di strategie di controllo.
Si analizzerà poi il caso del Myanmar, un mercato ancora non pienamente sviluppato con zone rurali senza accesso all’elettricità.
Si farà riferimento ad un bando promosso dalla World Bank per favorire il processo di elettrificazione rurale nel sud-est asiatico.
In definitiva obiettivo del presente lavoro di tesi è di mostrare come gli impianti off-grid possano risolvere il problema dell’elettrificazione rurale e di attuare un’ottimizzazione degli stessi, sfruttando i miglioramenti futuri riguardanti specialmente il sistema di accumulo, ma anche le strategie di controllo del regolatore. Ciò si realizzerà utilizzando come punto di partenza lo studio di varie installazioni realizzate da Tozzi Green nel contesto dell’elettrificazione rurale del Perù.
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Björkman, Jesper, and Simon Lundqvist. "Exploring off-grid electricity production in Sweden: Benefits vs costs." Thesis, KTH, Skolan för industriell teknik och management (ITM), 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-279592.
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Over the past decade, technologies that facilitate household electricity production and storage have seen a rapid development along with a significant cost reduction. Research points to an increased share of household-produced electricity within the existing national grids across the globe. In some cases, self-sufficiency is possible where households are able to decouple from the grid and become independent on their electricity, in other words, go off-grid. Furthermore, this change puts additional pressure on how the electricity system is set up, which, challenges prevailing incumbents to adapt. Depending on the geographical location, circumstances for selfsufficiency varies. Sweden is a country with high seasonal variations with its Northern position, which raises the question of how off-grid households are feasible and, how they can receive traction. To investigate possible changes within large technical systems such as the electricity system, which is a vital part of the society, theories within socio-technical systems have shown much promise. However, these theories often lack the more techno-economic aspect of concrete and future investment costs from a consumer perspective, suggesting an existing research gap. Hence, the purpose of this study is to provide further knowledge regarding off-grid applications in the Swedish Context. This is done by investigating what circumstances could trigger existing electricity consumers to go off-grid. The research process and structure of the report can be interpreted as indiscriminate, however, the study has focused on combining theories surrounding socio-technical changes whilst applying techno-economic modelling to strengthen the work, similar to a dual paper study. Data was collected in the form of a literature review and interviews to provide a holistic representation of off-grid and its nexus to the electricity system. In addition to this, complementing modelling of grid-connected-, prosumer-, and off-grid households were performed. Results point towards a scene where off-grid reaches grid parity within the coming two decades, which, will increase the economic rationale of investing in an off-grid. Opposingly, there is currently no economic rationale in off-grid applications considering the relatively low electricity costs in Sweden as of today. Moreover, conditions show promise if the adopters see beyond economics and, possesses a strong will towards independence. However, implications suggest that the high reliability and low costs of the Swedish electricity grid impedes the ability of new radical innovations to receive traction. Furthermore, this study has contributed by filling the research gap between socio-technical changes and techno-economic projects in regards to electricity systems. Consequently, contributing to the academic field of socio-technical change, it has been shown that the combination of socio-technical change and techno-economic projections is applicable and beneficial. Additionally, it can be argued that the results of this study highlight that the consumer have a greater role in the development of off-grid applications than what the theories suggest. Lastly, the electricity system is a complex mechanism and, to further strengthen the perception of how a relatively new application, as in the case of off-grid, will impact the system, appurtenant suggestions for possible future research within the area are proposed.Under det senaste decenniet har teknik som underlättar hushållens elproduktion och lagring haft en hastig utveckling tillsammans med en betydande kostnadsminskning. Forskning pekar på en ökad andel hushållsproducerad el inom de befintliga nationella elnäten över hela världen. I vissa fall är självförsörjning möjligt där hushållen kan koppla bort sig från nätet och bli oberoende av sin elförsörjning, med andra ord gå off-grid. Vidare leder en potentiell förändring mot offgrid till ytterligare påtryckningar på hur elsystemet är uppbyggt, vilket utmanar många aktörers sätt att agera. Beroende på geografisk plats så varierar förutsättningarna för självförsörjning. Sverige är ett land med stora säsongsvariationer i och med sin nordliga position, vilket väcker frågan om off-grid hushåll är genomförbara i Sverige och hur de kan skulle kunna etableras. För att undersöka möjliga förändringar inom stora tekniska system som elsystemet, som är en viktig del av samhället, har teorier inom socio-tekniska system visat vara till stor nytta. Däremot saknar dessa teorier emellertid den mer tekno-ekonomiska aspekten av konkreta och framtida investeringskostnader ur ett konsumentperspektiv, vilket antyder ett befintligt forskningsgap. Följaktligen är syftet med den här studien att ge ytterligare inblick om off-grid-applikationer i svenska sammanhang. Vilket har gjorts genom att undersöka vilka omständigheter som kan leda till att befintliga elkonsumenter går off-grid. Forskningsprocessen och strukturen i rapporten kan vara svårtolkat, men studien har fokuserat på att kombinera teorier kring socio-tekniska förändringar samtidigt som man använder teknoekonomisk modellering för att stärka arbetet. Data samlades in i form av en litteraturstudie och intervjuer för att ge en holistisk representation av off-grid och dess koppling till elsystemet. Utöver litteraturstudie utfördes kompletterande modellering av hushållsanslutna, prosumeroch off-gridhushåll. Resultaten pekar mot scenarion där off-grid når nätparitet under de kommande två decennierna, vilket kommer att öka den ekonomiska rationaliteten för att investera i ett off-grid. Det finns det för närvarande inga ekonomiska skäl till att investera off-grid-applikationer med tanke på de relativt låga elkostnaderna i Sverige idag. Förhållandena visar dessutom löfte om att potentiella användare ser förbi ekonomin och har istället en stark vilja mot självständighet. Implikationer tyder emellertid på att det svenska elnätets höga tillförlitlighet och låga pris hindrar nya radikala innovationers förmåga att ta få fäste. Det är argumenterbart att den här studien har bidragit med att fylla forskningsgapet mellan socio-tekniska förändringar och tekno-ekonomiska projektioner inom elsystem. Samtidigt har studien bidragit till det vetenskapliga området kring socio-tekniska visat på möjligheten och fördelen i att kombinera teorier kring socio-teknisk förändring och tekno-ekonomiska förändringar. Dessutom kan det hävdas att resultaten av den här studie visar att konsumenten har en större roll i utvecklingen av applikationer utanför nätet än vad teorierna föreslår. Slutligen är elsystemet en komplex mekanism, och för att ytterligare stärka uppfattningen om hur en relativt ny applikation, som i fallet utanför nätet, kommer att påverka systemet föreslås lämpliga förslag för eventuell framtida forskning inom området.
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Rotsios, Christopher. "Analysis and Design of An Off-Grid Residential Power System." DigitalCommons@CalPoly, 2020. https://digitalcommons.calpoly.edu/theses/2214.
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This thesis aims to provide a recommended power system design for optimal efficiency, reliability, and cost in off-grid applications. The power system examined in this project is a residence in an off-grid community called Quail Springs that generates its energy from roof mounted solar panels. The existing system was analyzed to see what equipment can remain, what needs to be upsized, and what needs to be added to the system. Two power systems are considered for the residence: a fully AC power system and a hybrid AC/DC power system. Simulations were run in PSCAD to compare the efficiencies of the two proposed systems at varying load. The results of the simulations showed the hybrid power system to be generally less efficient when supplying AC and DC loads, but greater than 5% more efficient when only supplying DC load. Although the hybrid AC/DC system is approximately 70% more expensive, it is still the final recommended design due to potential efficiency gains and in an effort to provide educational opportunities that may lead to further efficiency gains in future hybrid AC/DC power systems.
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Leitman, Valentín. "Koncept nabíjecí stanice s možností off-grid provozu pro elektrokola." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2017. http://www.nusl.cz/ntk/nusl-319544.
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This thesis deals with charging stations for electric bicycles powered by renewable energy. The aim of this work is to make a proposal for the hybrid charging stations for electric bicycles, which will work independently and, if necessary, will be backed up by a network. In this thesis is entered theoretical information on the issue of electric bicycles, the batteries, charging stations, the connectors of chargers, and photovoltaic systems. The practical part of this thesis is the basic design of the charging station and its design of the mathematical model of the individual parts in Simulink program, which are linked to the actual design of the charging station. In conclusion, this thesis deals with energy and economic analysis of the proposed system, therein included various methods of assessing investment recommendations of appropriate processing methods and overall assessment of the subject.
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Bengtson, Mattias. "Optimering av energisystem för fjällstugor utanför elnätet : En fallstudie av fyra stugor i Abiskoområdet." Thesis, Uppsala universitet, Elektricitetslära, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-414376.
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The Swedish Tourist Association, STF, is an organization which strives to make the Swedish nature more accessible to people. Since its founding, STF has been a key player in the development of the tourism in the Swedish mountain regions. Today the organization have 44 mountain cabins along the Swedish mountain range, and a majority of the huts are completely off-grid with no other connection to them but hiking trails. To accommodate for the needs of hikers and skiers throughout the year, the huts need electricity for lighting and in many cases cash registers and satellite modems to run small shops selling simple commodities. Many of the huts use solar energy combined with lead acid batteries, but not all of them can make it through the year without the use of a backup gasoline generator. This master thesis analyzes the different energy systems of four huts run by STF and using solar radiance data from PVGIS to calculate whether or not they are self-sufficient throughout the year using only solar energy. In the cases where the huts were found not to be self-sufficient, suggestions on actions that STF could implement to optimize the systems were found. For two out of the four huts, the thesis found that they were not self-sufficient, but after optimizing the energy systems with new energy saving appliances as well as tilting the solar panels between the winter and summer seasons, all four huts were found to be able to reach self-sufficiency.
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Bai, Wenshuai. "DC Microgrid optimized energy management and real-time control of power systems for grid-connected and off-grid operating modes." Thesis, Compiègne, 2021. http://www.theses.fr/2021COMP2586.
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Le travail de recherche de cette thèse se concentre sur l’élaboration de deux modes de fonctionnement du microréseau à savoir : mode connecté au réseau, mode hors réseau comprenant les modes îloté et isolé. Le problème de la défaillance du réseau en mode connecté au réseau et la faible fiabilité de l'alimentation électrique en mode hors réseau doivent être résolues. Ainsi, le but de cette thèse est de proposer un microréseau DC combinant à la fois les avantages du mode connecté au réseau et ceux du mode isolé. On obtient ainsi un microréseau DC qu’on peut qualifier de complet. Le microréseau DC complet contient les sources d'énergie renouvelables, le stockage et le réseau public, et les sources de secours sont utilisées pour réduire le délestage. Dans ce microréseau DC, un système de supervision est proposé dans le but de gérer le flux des puissances. La gestion de la puissance en temps réel dans la couche opérationnelle du système de supervision permet de maintenir l'équilibre de puissance. Dans la couche d'optimisation du système de supervision, l'optimisation journalière est proposée afin de minimiser le coût d'exploitation global. Les résultats de la simulation montrent que le microréseau DC complet peut minimiser les coûts d'exploitation. Ensuite, le système de supervision prend en compte l'efficacité dynamique du convertisseur pour résoudre le problème lié à la qualité de la puissance du microréseau qui peut être dégradée à cause de la tension instable du bus DC. Les résultats de la simulation montrent que la prise en compte de l'efficacité dynamique du convertisseur dans la couche opérationnelle du système de supervision permet de réduire les fluctuations de la tension du bus DC. En ce qui concerne l'importance de la prédiction PV pour l'optimisation de la veille, deux modèles de prédiction sont étudiés et comparés pour donner une puissance de prédiction PV précise. Les résultats montrent que les deux modèles ont presque les mêmes résultatsThis thesis focus on the research of the DC microgrid following two operation models: grid-connected mode, and off-grid mode including the islanded and isolated modes. The aim of this thesis is to propose a DC microgrid combining the advantages of the grid-connected or the off-grid mode, which named full DC microgrid. ln the full DC microgrid, the renewable energy sources, storage, and public grid are included, and the back-up sources also applied to reduce the load shedding. ln the full DC microgrid, a supervisory system is proposed to manage the power. The real-time power management in the operational layer of the supervisory system can keep the power balance. ln the optimization layer of the supervisory system, the day-ahead optimization is proposed to achieve the global minimal operation cost. The simulation results show that the full DC microgrid combines both advantages of the grid-connected and the off-grid mode to minimize the operating cost. Then, the supervisory system considers the dynamic efficiency of the converter to solve the problem that the power quality of the microgrid is degraded due to the unstable DC bus voltage caused by the inaccurate power control. The simulation results show that considering the dynamic efficiency of the converter in the operational layer of the supervisory system, the fluctuation of the DC bus voltage can be reduced. Regarding the importance of the PV prediction for the day-ahead optimization, two prediction modes are studied and compared to give a robust PV prediction power. The results are that the two models almost have the same results
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Oama, Clint Arthur. "Hybrid Energy System for Off – Grid Rural Electrification(Case study Kenya)." Thesis, Högskolan på Gotland, Institutionen för kultur, energi och miljö, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-217001.
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The aim of this thesis study is to design a hybrid energy system comprised of wind turbines, diesel generators and batteries to provide electricity for an off - grid rural community in Kenya. Wind Measurements collected over six years from 12 locations in Kenya have been studied and one site selected for this project due to its wind potential, geographical location and socio-economic potential. The energy system is designed to cater for the electricity demand of 500 households, one school, one medical clinic and an irrigation system. The system will support up to 3000 people. The Hybrid Optimization Model for Electric Renewables (HOMER) is the software tool that has been used to simulate the hybrid system and analyze its results. The optimization has been carried out and presented according to cost of electricity and sensitivity graphs have been used demonstrate the optimization based on diesel price and wind turbine hub height.
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Swanepoel, Jacques Philip. "Off-line signature verification using classifier ensembles and flexible grid features." Thesis, Stellenbosch : University of Stellenbosch, 2009. http://hdl.handle.net/10019.1/3218.
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Thesis (MSc (Mathematical Sciences))—University of Stellenbosch, 2009.Thesis presented in partial fulfilment of the requirements for the degree of Master of Science in applied mathematics at Stellenbosch University
ENGLISH ABSTRACT: In this study we investigate the feasibility of combining an ensemble of eight continuous base classifiers for the purpose of off-line signature verification. This work is mainly inspired by the process of cheque authentication within the banking environment. Each base classifier is constructed by utilising a specific local feature, in conjunction with a specific writer-dependent signature modelling technique. The local features considered are pixel density, gravity centre distance, orientation and predominant slant. The modelling techniques considered are dynamic time warping and discrete observation hidden Markov models. In this work we focus on the detection of high quality (skilled) forgeries. Feature extraction is achieved by superimposing a grid with predefined resolution onto a signature image, whereafter a single local feature is extracted from each signature sub-image corresponding to a specific grid cell. After encoding the signature image into a matrix of local features, each column within said matrix represents a feature vector (observation) within a feature set (observation sequence). In this work we propose a novel flexible grid-based feature extraction technique and show that it outperforms existing rigid grid-based techniques. The performance of each continuous classifier is depicted by a receiver operating characteristic (ROC) curve, where each point in ROC-space represents the true positive rate and false positive rate of a threshold-specific discrete classifier. The objective is therefore to develope a combined classifier for which the area-under-curve (AUC) is maximised -or for which the equal error rate (EER) is minimised. Two disjoint data sets, in conjunction with a cross-validation protocol, are used for model optimisation and model evaluation. This protocol avoids possible model overfitting, and also scrutinises the generalisation potential of each classifier. During the first optimisation stage, the grid configuration which maximises proficiency is determined for each base classifier. During the second optimisation stage, the most proficient ensemble of optimised base classifiers is determined for several classifier fusion strategies. During both optimisation stages only the optimisation data set is utilised. During evaluation, each optimal classifier ensemble is combined using a specific fusion strategy, and retrained and tested on the separate evaluation data set. We show that the performance of the optimal combined classifiers is significantly better than that of the optimal individual base classifiers. Both score-based and decision-based fusion strategies are investigated, which includes a novel extension to an existing decision-based fusion strategy. The existing strategy is based on ROC-statistics of the base classifiers and maximum likelihood estimation. We show that the proposed elitist maximum attainable ROC-based strategy outperforms the existing one.
AFRIKAANSE OPSOMMING: In hierdie projek ondersoek ons die haalbaarheid van die kombinasie van agt kontinue basis-klassifiseerders, vir statiese handtekeningverifikasie. Hierdie werk is veral relevant met die oog op die bekragtiging van tjeks in die bankwese. Elke basis-klassifiseerder word gekonstrueer deur ’n spesifieke plaaslike kenmerk in verband te bring met ’n spesifieke skrywer-afhanklike handtekeningmodelleringstegniek. Die plaaslike kenmerke sluit pikseldigtheid, swaartepunt-afstand, oriëntasie en oorheersende helling in, terwyl die modelleringstegnieke dinamiese tydsverbuiging en diskrete verskuilde Markov modelle insluit. Daar word op die opsporing van hoë kwaliteit vervalsings gefokus. Kenmerk-onttreking word bewerkstellig deur die superponering van ’n rooster van voorafgedefinieerde resolusie op ’n bepaalde handtekening. ’n Enkele plaaslike kenmerk word onttrek vanuit die betrokke sub-beeld geassosieer met ’n spesifieke roostersel. Nadat die handtekeningbeeld na ’n matriks van plaaslike kenmerke getransformeer is, verteenwoordig elke kolom van die matriks ’n kenmerkvektor in ’n kenmerkstel. In hierdie werk stel ons ’n nuwe buigsame rooster-gebasseerde kenmerk-ontrekkingstegniek voor en toon aan dat dit die bestaande starre rooster-gebasseerde tegnieke oortref. Die prestasie van elke kontinue klassifiseerder word voorgestel deur ’n ROC-kurwe, waar elke punt in die ROC-ruimte die ware positiewe foutkoers en vals positiewe foutkoers van ’n drempel-spesifieke diskrete klassifiseerder verteenwoordig. Die doelwit is derhalwe die ontwikkeling van ’n gekombineerde klassifiseerder, waarvoor die area onder die kurwe (AUC) gemaksimeer word - of waarvoor die gelyke foutkoers (EER) geminimeer word. Twee disjunkte datastelle en ’n kruisverifi¨eringsprotokol word gebruik vir model optimering en model evaluering. Hierdie protokol vermy potensiële model-oorpassing, en ondersoek ook die veralgemeningspotensiaal van elke klassifiseerder. Tydens die eerste optimeringsfase word die rooster-konfigurasie wat die bekwaamheid van elke basis-klassifiseerder maksimeer, gevind. Tydens die tweede optimeringsfase word die mees bekwame groepering van geoptimeerde basis-klassifiseerders gevind vir verskeie klassifiseerder fusiestrategieë. Tydens beide optimeringsfases word slegs die optimeringsdatastel gebruik. Tydens evaluering word elke optimale groep klassifiseerders gekombineer met ’n spesifieke fusie-strategie, her-afgerig en getoets op die aparte evalueringsdatastel. Ons toon aan dat die prestasie van die optimale gekombineerde klassifiseerder aansienlik beter is as dié van die optimale individuele basis-klassifiseerders. Beide telling- en besluit-gebaseerde fusie-strategieë word ondersoek, insluitend ’n nuwe uitbreiding van ’n bestaande besluit-gebasseerde kombinasie strategie. Die bestaande strategie is gebaseer op die ROC-statistiek van die basis-klassifiseerders en maksimum aanneemlikheidsberaming. Ons toon aan dat die voorgestelde elitistiese maksimum haalbare ROC-gebasseerde strategie die bestaande strategie oortref.
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Mentz, Matthew. "Unearthing the determinants required for off-grid subsistence : a case study." Thesis, Stellenbosch : Stellenbosch University, 2013. http://hdl.handle.net/10019.1/80153.
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Thesis (MPhil)--Stellenbosch University, 2013.ENGLISH ABSTRACT: This study is based on the personal four-year journey of the researcher in an attempt to develop an off-grid, sustainable self-sufficient livelihood and habitation on a 1 000-square metre piece of rural land in the heritage mission village of Suurbraak, Western Cape, South Africa. This single case study attempts to embody a comprehensive antithesis to the current rural settlement approach implemented in South Africa. The approach is philosophical, applying Hegel’s “determinate negation” conception of reality, as dialectic between a conception of “thesis” as global, scientific and regulated resulting in large-scale agriculture, poisoning of nature and inappropriate low-cost housing and its “antithesis” as grounded, philosophical, healthy subsistence habitation on the actual land. This study, shaped by a literature review, proposes a concept coined ‘niche settlement’, comprising four focus areas as regards sustainable self-sufficiency: an owner-built dwelling from local materials, farm produce for consumption and self-medication, rain and energy harvesting, and taking responsibility for waste. In order to validate the case study contextually, an action research methodological approach was adopted. This began with a field study to interview marginal small-scale farmers, enriched by a land-use survey in the Suurbraak agri-village, in order to clarify the determinants for successful subsistence. These were land availability, proximity of land to homestead, appropriate scale, access to water, enabling legislation, and access to inputs and labour. The critical nature of these determinants is then shown as regards the niche settlement case study. The interplay of Swellendam Municipality regulations reveals contradictions that entail that the above determinants are not facilitated. This threatens a vulnerable two-century old agrarian heritage. The ensuing dialectic between the researcher and municipal officials who - when confronted by the contradictions - undertook to revise certain zoning decisions that threatened the viability of niche settlement approaches. The determinants may prove fertile ground for further research as criteria to shape rural settlement policy with respect to land use, particularly given the need to factor in the looming global recession, the food crisis and peak oil.
AFRIKAANSE OPSOMMING: Hierdie studie is op die vier jaar lange persoonlike reis van die navorser self baseer. Dit behels 'n poging om 'n kwart akker stuk grond in die landelike erfenis sending-dorp van Suurbraak, in die Wes-Kaap Provinsie in Suid-Afrika te bewoon en daarop ‘n off-grid, volhoubare en selfversorgende bestaan te ontwikkel. Hierdie enkele gevallestudie poog om 'n omvattende antitese te beliggaam tot die benadering tot landelike nedersetting soos tans in Suid-Afrika geïmplementeer. Die benadering is filosofies, en pas toe Hegel se "beslissende weiering" konsepsie van die werklikheid, as dialektiek tussen 'n opvatting van die "tesis" as: globaal, wetenskaplik en gereguleerd wat grootskaalse landbou, die vergiftiging van die natuur en lae-koste behuising tot gevolg het en sy "antitese": gegrond, filosofies en gesonde bestaansboerdery op die grond. Die dialektiek kontrasteer die tesis op 'n makro-en kollektiewe vlak en die antitese op 'n mikro-en persoonlike vlak, wat aanleiding gee tot 'n "sintese", waaruit nuwe antwoorde ontstaan in die beslissende ingebed, eerder as in algemene teoretiese abstraksies. Kritiese oplossings lê vlak versteek in die mikrokosmos detail of in die konteks. Dit wil sê, is gedetermineerd vermom en vereis 'n metodiese en gefundeerde benadering wat nóg weke nóg maande, maar jare eerder van geduldige navorsing verg om te bemag. Die Hegeliaanse metode soos gebruik beklemtoon dat dit onwaarskynlik is dat "begrippe" met hul kontekstuele "standaard begrippe" sal ooreenstem, maar in die proses van aanpassing word eindelose antwoorde uit die fynere detail van bepaalbare werklikheid opgetel. Hierdie antwoorde, wanner van toepassing, het die potensiaal om antitetiese manifestasies van die werklikheid in werklikheid te verifieer; die mikro is in staat om die makro te verklaar deur middel van 'n proses van die verwesenlikte waarheid. Hierdie studie, deur 'n literatuuroorsig toegelig, stel 'n konsep geskep as "nis nedersetting” voor. Dit bestaan uit vier fokusareas wat betref volhoubare self-genoegsaamheid: 'n eienaargeboude woning van plaaslike materiale, eie plaasprodukte vir verbruik en selfmedikasie, die oes van reën en energie, en die neem van verantwoordelikheid vir afval. Ten einde die gevallestudie kontekstueel te waarmerk, is 'n aksie-navorsing metodologiese benadering ingeneem. Dit het begin met 'n gedokumenteerde veldstudie waarin onderhoude met marginale kleinskaal boere gevoer is en is verryk deur 'n grondgebruik-opname in die Suurbraak agri-dorp, ten einde die determinante vir 'n suksesvolle bestaansboerdery uit te lig. Dit het gelei tot 'n dieper begrip van wat die sukses van soortgelyke nis projekte bepaal: die beskikbaarheid van ’n (grond-)perseel, bewerkbare grond naby die woning geleë, toepaslike skaal, toegang tot water, bemagtigende wetgewing en toegang tot insette en arbeid. Die kritiese aard van hierdie determinante word met betrekking tot die gevallestudie getoon. Die wisselwerking van die Munisipaliteit Swellendam se regulasies openbaar teenstrydighede wat behels dat die bogenoemde determinante nie gefasiliteer is nie). Dit is teleurstellend deurdat dit 'n kwesbare twee-eeue oue agrariese erfenis bedreig. Die daaropvolgende dialektiek tussen die navorser en munisipale amptenare wat - gekonfronteer met die teenstrydighede geopenbaar in wetgewing en regulasies met betrekking tot die erfenis, grondgebruik en sonering - onderneem het om sekere besluite wat die lewensvatbaarheid van die nis nedersetting benaderings bedreig het om te keer, manifesteer sodoende as 'n sintese. 'n Verdere voorbeeld van sintese is die voorstel dat die belangrikste determinante effektief toegepas kan word as kriteria om vorm te gee aan die landelike nedersettingsbeleid met betrekking tot grondgebruik, veral gegewe die behoefte om die dreigende wêreldwye resessie, die voedsel-krisis en piek olie saam daarby onder sig te neem.
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Davies, Neale. "Novel, induced flow, centrifugal water pumping system for off grid application." Thesis, University of Liverpool, 2015. http://livrepository.liverpool.ac.uk/2037461/.
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Water provision in rural areas represents a significant challenge, especially within the context of resource and sanitation in developing countries. High set-up costs, lack of installation expertise and reliability issues, arising from fluctuating operational conditions, have prevented many people from receiving the full benefit of automated pumping systems. The specific aim of this thesis is to assess the feasibility of using a tunable, induced flow subsystem as a means of optimising the power utilization and performance of a centrifugal pump over a wider range of operating conditions than typically expected. More generally, the research presented is undertaken to reduce the high implementation costs and localised limitations of rural water pumps by developing the theory towards a ‘’one-size-fits-all’’ pumping system. The theoretical analysis of an induced flow centrifugal pumping system is presented, coupled with the analogous electrical system. The results of simulations performed using both systems are compared to experimental results, obtained using an induced flow subsystem (IFS) test rig constructed at the University of Liverpool. All sets of results demonstrate consistent IFS characteristics, identifying its capability to maintain maximum power point (MPP) operation of the centrifugal pump irrespective of load. Further, the experimental results reveal a boost in output pressure which enables the pump to achieve an improved hydraulic power and increased operating range over the same system without an IFS. It is concluded that, through the addition of an IFS, the performance of a centrifugal pump may be decoupled from its operating head, expanding its range of serviceable conditions and demonstrating potential to develop a ‘’one-size-fits-all’’ system. Ultimately, this could offer a cheaper and more reliable supply of a resource which is vital to life in any rural location: clean water.
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Raji, Atanda Kamoru. "Modelling and development of fuel cell off grid power converter system." Thesis, [S.l. : s.n.], 2008. http://dk.cput.ac.za/cgi/viewcontent.cgi?article=1039&context=td_cput.
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Williamson, Samuel. "Modular and scalable low-head pico-hydro generation for off-grid networks." Thesis, University of Bristol, 2013. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.616869.
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Over 1.3 billion people across the world do not have access to electricity, with most living outside urban environments. In these rural, remote locations with low population density, the cost of extending the grid is very high. If a location has a river nearby, pico-hydropower is a cost-effective way of providing off-grid electricity. Typically pico-hydro units are stand-alone and can only provide enough power for basic domestic services such as lighting and mobile phone charging. However, if these pico-hydro units were connected together in a network, the available power could scale up and provide a more reliable source to support health posts, schools and income generation activities such as grain processing, as well as domestic demand. This thesis investigates the interconnectivity of low-head pico-hydro modules to form a scalable off-grid network. A specification for a system is derived from user requirements and the current state of technology resulting in a concept for the network. Each unit is to be identical, operating at low head and connecting onto an AC grid using a power-electronic front-end . Using this specification, a new methodology is developed using weighted quantitative and qualitative criteria to select a turbine to match the specification. A single-jet Turgo turbine is chosen; a turbine design not commonly used at low heads. Using a low-speed generator and power-electronic front-end it is shown to satisfy many of the quantitative and qualitative criteria in this case. A quasi-steady-state 2D model for the Turgo turbine is developed with a jet interception efficiency model that calculates the percentage of jet that impinges the turbine cup. An experimental set-up for the turbine is designed and scaled performance tests are carried out and compared with the model. Using a Design of Experiments method and further optimisation tests, a Turgo system arrangement was found with a maximum jet-to-mechanical efficiency of 91 % at 3.5 m head. The generator unit, made up of turbine, generator, rectifier, DC-DC converter and inverter, is simulated in Simulink. The generator units do not communicate between themselves, so each inverter uses a modified version of droop control for low voltage grids where the output power is proportional to the available turbine power. This allows each unit on the network to support voltage and frequency regulation on the AC grid. A simulation of the system is developed and different control parameters are varied to understand their effect on the grid output and unit synchronisation. The control system is then validated experimentally using hardware-in-the-loop techniques, showing how the proportional droop control is able to successfully share load between generator units of different power rating, whilst mitigating distance between the source and load. Finally, a full-scale generator unit is designed and mocked up in the installation environment. The unit is modularised to aid fault identification and part replacement by unskilled labour, with an estimated cost of £1300 per unit, which can generate 1 kW.
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Dave, Shreya H. "Life cycle assessment of off-grid lighting applications : kerosene vs. solar lanterns." Thesis, Massachusetts Institute of Technology, 2008. http://hdl.handle.net/1721.1/54450.
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Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2008.Cataloged from PDF version of thesis.
Includes bibliographical references (p. 37-38).
Access to electricity in developing countries is minimal and if available, often unreliable. As a result, fuel-based kerosene lighting is the most common solution to lighting necessities. However, kerosene combustion affects indoor air quality and relies on a non-renewable fossil fuel subject to price volatility. Thus, solar lanterns are being introduced to developing markets, but incur their own energy and emissions intensity from more complex manufacturing processes and requirements. Life cycle assessments examine the energy required and the emissions released over the entire existence of a product or process to allow for quantitative comparison among technology options. The results from a "cradle-to-user" life cycle assessment of the lighting options are displayed in Figure 1 below ... The values reported do not clearly indicate that it is a sustainable decision to transition to solar-based lighting from the conventional use of kerosene combustion. However, understanding the data presents further opportunities for reducing the impact of lighting. The economic payback time of a solar lantern, the distribution emissions in location and time, and the challenges of implementation on a large scale are among these critical review considerations.
by Shreya H. Dave.
S.B.
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Le, Quanghuy. "Off-Grid Public Lighting System - Design and Characterization of an LED Luminaire." DigitalCommons@CalPoly, 2011. https://digitalcommons.calpoly.edu/theses/514.
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The technological advances made in the photovoltaic industry have led to a vast exploration of self-sustaining systems. As the consumer demand for electricity rises from increasing population and development of existing technologies, new practices in system designs are required to relieve the impact on the electrical grid.
This thesis delves into a developing concept of using photovoltaic modules for roadway lighting, with emphasis on establishing the fundamental design for a “spot-lighting” luminaire. By effectively extinguishing various sections of the luminaire in the absence of pedestrian trafficking, the proposed design and implementation will minimize the prolonged costs, as well as the overall power consumption. Furthermore, as the first stage in development, this thesis includes justifications for design and part selection, while complying with numerous requirements set forth by the City of Los Angeles and in accordance with regulations established by the Illuminating Engineering Society of North America (IESNA). To accomplish these goals, copious amounts of performance tests and simulations, both before and after system implementation, will characterize the overall feasibility of the stand-alone lighting application.
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Brumana, Giovanni (ORCID:0000-0002-7081-1111). "Solar Cooling Technologies and Off-Grid Building Design in Hot Climatic Conditions." Doctoral thesis, Università degli studi di Bergamo, 2018. http://hdl.handle.net/10446/105272.
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Global warming is the main problem of the century. The scientific community is addressing many efforts to face the environmental problems and solar cooling systems are one of the best candidates.
The thesis proposes a solution developed through the improvement of the three main aspects of the chain: building energy efficiency, cooling production and distribution. The Middle East region represents the challenge locations for developing new technologies for air conditioning.
This work proposes the improvement of sustainable buildings and promote an innovative design to reduce energy consumption.
The development of district cooling systems allows the optimization of the cooling production and reduces the waste associated with single users, enabling the installation of higher efficiency technologies.
Solar cooling systems, the main focus of this research, are the best available solution to significantly reduce power consumption. Moreover, even under the economic aspect can certainly replace the traditional systems that have so far been adopted.
Particular attention is devoted to the heat rejection systems, the only component that can improve the cooling plants performance in hot climates.
The sun, cause of the cooling load, must effectively turn into the solution of the problem.
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Cingel, Štefan. "Malá fotovoltaická elektrárna na rodinném domě." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2018. http://www.nusl.cz/ntk/nusl-376919.
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This diploma thesis deals with the principle of photovoltaic phenomenon and the distribution of photovoltaic systems. It also informs the reader about the possibilities of using the "Green Savings" subsidy within the program "New Green Savings" of the Ministry of the Environment. Last, but not least, it maps the energetic demands of the family house and, on the basis of it, presents the possible design of the photovoltaic system, including the estimation of the economic return.
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Rahnama, Roxanne. "Essays on the attitudes, behavior, and decision-making of income-constrained electricity consumers : implications for integrative grid and off-grid business model planning." Thesis, Massachusetts Institute of Technology, 2018. http://hdl.handle.net/1721.1/117795.
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Thesis: S.M. in Technology and Policy, Massachusetts Institute of Technology, School of Engineering, Institute for Data, Systems, and Society, 2018.This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
Cataloged student-submitted from PDF version of thesis.
Includes bibliographical references (pages 116-126).
Electrification rates in a number of low income and developing countries have faced steady improvements in the last few decades, with impressive technological advancements in both the grid and off-grid sectors. There are nonetheless vast swaths of the planet - largely concentrated in India and sub-Saharan Africa - that continue to face troublesome gaps, along both extensive and intensive margins, in progress toward the goal of universal electricity access by 2030. In spite of widespread technical developments, growth of digital platforms for stakeholder engagement, and improvements in technocratic optimization tools for planning, stubborn challenges remain in the distribution sector of LIDCs, placing persistent constraints on equitable growth, private investment, and development for the 1.6 billion rural citizens living in the dark during an era of rapid urbanization. Attaching particular focus to India, which houses 300 million of the global energy poor, this thesis will argue that inadequate attention to consumer attitudes, behavior, and decision-making patterns perpetuates gridlocks in surpassing the final frontiers of global electrification. This overarching argument will be developed over a series of standalone, yet intellectually connected essays that derive from a mixture of applied political economy methods: first, an in-depth context analysis of electricity distribution in India will be introduced. The second essay extends beyond the Indian context and is largely organized as a state-of-knowledge paper that examines the complex relationship between ability-to-pay, willingness-to-pay, and welfare, and the ways in which nuanced socioeconomic, behavioral, and technical dynamics endogenously interact with these variables. In doing so, several hypotheses and case study analyses will be presented and deficiencies in this nascent literature which merit more academic engagement will be highlighted. The ultimate paper will conclude by offering different sets of consumer engagement and behavioral design recommendations that can advance an integrative approach to grid and off-grid business model planning. In holistically examining the complex nexus between electricity access and the consumer psyche, this thesis aims to provide deeper insights into the lives of the energy poor and advance a human-centered design approach to electrification planning in developing contexts.
by Roxanne Rahnama.
S.M. in Technology and Policy
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Bondesson, Anna. "Comparative LCA model on renewable power solutions for off-grid radio base stations." Thesis, KTH, Industriell ekologi, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-53247.
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Globally, there are approximately 900 000 telecommunication radio base station sites (RBS-sites)located in areas without access to the electrical grid. Traditionally, these sites are powered by dieselgenerators, consuming large amounts of fossil diesel fuel. Diesel combustion is connected both toenvironmental impacts and high economical expenses for the mobile operators. As the mobilenetwork expansion is increasingly located in off-grid areas of developing countries, the search forrenewable power alternatives has been intensified. This Master thesis presents results from a life cycle assessment (LCA) of photovoltaic and windturbine hybrid power configurations for off-grid RBS-sites. The LCA covers environmental impactsfrom all life cycle activities of the hybrid system: from raw material extraction, manufacturing, andtransportation, to on-site usage, and disposal. To enable assessment of variable hybrid configurations, four scalable sub-models were constructed:one diesel sub-model including the generator and yearly diesel consumption, one back-up batterysub-model, one PV module sub-model and one wind turbine sub-model. Included in the sub-modelswere required site equipment; e.g. foundations for generators, PV modules and battery banks, powerconverters, fuel tanks and possible housings. The number of generators, liters of fuel consumed peryear, number of battery cells, square meters of PV module and number of wind turbines were set asvariables. Hereby RBS-sites with different capacities and availability of renewable source could bemodeled. A hybrid configuration including 21 square meters photovoltaic modules, one wind turbine, a storageof 36 (12 V) batteries and one generator back-up consuming 1500 liters of diesel fuel per year wasevaluated. The hybrid site represents between 11 and 16 percent of the different environmentalimpact potentials, global warming potential specifically representing 13 percent, caused by acorresponding traditional diesel site consuming 20000 liters of fuel per year. The most importantparameters influencing the environmental performance of the renewable hybrid site following thediesel fuel production and combustion are the production energy mix and energy intensive processesincluding the up-stream silicon and lead processing. The thesis confirmed great environmental benefits of using wind and solar power at RBS-sites. Theadditional gain of applying wind power when feasible to decrease the PV module area or batterycapacity required was also demonstrated. The great importance of manufacturing location andelectricity mix should encourage Ericsson to map supplier manufacturing locations, searchingpossibilities to decrease the environmental impacts from the manufacturing phase of the differentsub-systems.Idag finns det omkring 5 miljoner radiobasstationer i det i det globala telekomnätet, varav 900000 ärbelägna i områden utan tillgång till elektricitet. Traditionellt drivs dessa stationer av dieselgeneratorersom konsumerar stora mängder diesel. Dieselförbränningen bidrar både till lokala och globalamiljöeffekter samt höga driftkostnader för mobiloperatörerna. Expansionen av mobilnätet sker i alltstörre utsträckning i områden i utvecklingsländer utan elförsörjning, vilket har ökat intresset föralternativa kraftkällor. Inom examensarbetet har ett redskap för jämförande livscykelanalys (LCA) av förnyelsebara krafthybridlösningarför radiobasstationer utvecklats. Hybriderna kombinerar solceller och vindturbinermed dieselförbränning och batterier. Genom att använda LCA inkluderas miljöeffekter från alla steg i hybridsystemets livscykel; frånutvinning av råmaterial och tillverkning av sub-system, transport, användning på RBS-siten till denslutliga avvecklingen. För att kunna utvärdera olika hybridkonfigurationer skapades 4 olika delmodeller: en delmodell fördieselförbränning innefattande generator och dieselkonsumption, en batteri-delmodell, en PVdelmodellsamt en vindturbin-delmodell. Delmodellerna inkluderar även nödvändiga komponentersom betonggrund till generatorer, PV-modulerna och batteribanken. Antal dieselgeneratorer,battericeller, vindturbiner samt PV-moduler och liter dieselkonsumption kan varieras för att simuleraen specifik anläggning. En hybridlösning med 21 m2 solceller, en vindturbin, 36 stycken (12V) battericeller och endieselgenerator som konsumerar 1500 liter diesel per år analyserades. Hybridlösningen ger upphovtill miljöeffekter motsvarande mellan 11 och 16 procent, global uppvärmning motsvarande 13procent, av miljöeffekterna orsakade av en traditionell dieselkonfiguration som konsumerar omkring20000 liter diesel per år. Betydelsefulla parametrar som påverkar miljöeffekterna frånhybridlösningen förutom produktion och förbränning av diesel är vilken elektricitetsmix somanvänds vid tillverkning av de olika komponenterna och energiintensiva processer som kisel- ochblyframställning. Resultaten tydliggör de stora minskningar av miljöeffekterna som en övergång från dieselförbränningtill sol- och vindkraft på RBS-anläggningar kan ge. Den relativa förbättringen av att installeravindturbiner för att minimera mängden sol- och battericeller har även visats. Betydelsen avproduktionsplats och elektricitetsmix för den totala miljöpåverkan bör motivera Ericsson attkartlägga och välja tillverkare som innebär ett litet bidrag till de totala miljöeffekterna.
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Amusat, O. O. "Design and optimization of hybrid renewable energy systems for off-grid continuous operations." Thesis, University College London (University of London), 2017. http://discovery.ucl.ac.uk/1566604/.
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The mining industry accounts for a significant portion of the energy demand by the industrial sector. The rising demand for metals around the world, coupled with the depletion of readily accessible ore deposits, has led to mining operations moving to more remote locations with no grid supply of energy. As a result, the operations require transport of fuel over large distances, leading to a significant increase in the overall mining cost. Renewable energy is considered to be the most promising solution to the mining industry energy problem. This work investigates the possibility of operating remote mines on local generation from renewables. A survey of recent literature revealed that while a lot of research had been done on hybrid renewable energy systems design and sizing, little thought had been given to accounting for the stochastic nature of renewable resources in the sizing process. Previous works focused on the sizing of PV-wind-battery systems; other potential generation and storage technologies were largely ignored. The challenge of intermittency in the power output of renewable generation systems had also largely been ignored. This thesis extends the state of the art on hybrid systems sizing by developing models and methodologies to address these challenges. A novel hybrid energy system integrating thermal and electrical renewable generation options with multiple large scale energy storage options is considered in this thesis. Models are developed for the different components of the energy system, with dynamic models incorporated for the material and energy balances of the storage alternatives, leading to a system of nonlinear differential algebraic equations (DAEs). The temporal nature of the renewable resources is accounted for by considering multiple stochastic renewable input scenarios generated from probability distribution functions (PDFs) as inputs into the system model. A reliability measure to quantify the impact of weather-based variability, called the modified loss of power supply probability, is developed. A bi-criteria sizing methodology which allows for the stochastic nature of renewable resources to be accounted for is presented. The approach combines the time series approach to reliability evaluation with a stochastic simulation model. Two approaches for mitigating the impact of intermittency in power outputs of renewable generation technologies are also developed. The first approach is based on system redesign, while the second approach is based on the introduction of an instantaneous response storage option. Case studies were presented to demonstrate the various methodologies. The results show that climate-based variability can have a significant impact on the cost and performance of hybrid energy systems and should always be accounted for in the sizing process. Intermittency needs to be accounted for in some form at the design stage as it can have an impact on the choice of technologies. The integration of thermal and electrical power generation and storage options provide a way to reduce hybrid system costs. The methodologies developed in this thesis are applicable to any location and can easily be extended to incorporate other generation and storage alternatives. They provide the decision maker with necessary information for making preliminary sizing decisions.
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Nygren, Joel, and Patric Hjort. "Systemuppbyggnad och entreprenörskap från grunden : Fallstudie: ”off- grid” vatten- och avloppslösning på Värmdö." Thesis, Mälardalens högskola, Industriell ekonomi och organisation, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-49101.
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Research questions: How can the Aspvik model be useful for the traditionally functioning water and sewage industry? What are the main challenges for regime actors to implement systems similar to those derived from the Aspvik model? Purpose: The purpose of the study is two-fold. Firstly, we intend to investigate system development and entrepreneurship from below in a local project in the water and sewage industry and its business model. Secondly, the study aims to provide an understanding of how the organization and the development process differ between the local Aspvik project and the existing regime within the water and sewage industry. Method: The study was of a qualitative nature based on an abductive approach. The theoretical framework was based on scientific articles and publications as well as books. The empirical data collection consisted of the collection of primary and secondary data, of which primary data was obtained through a total of 13 semi-structured interviews and secondary data via web pages, public print (laws and regulations) and other sources. A thematic analysis was performed based on the theoretical framework and the empirical data. Conclusion: The Aspvik model can generate usefulness as it contributes by providing a businesslike approach with transparency and visualization of what opportunities the industry actors have and what it may cost. With transparency, the current problems and bottlenecks in the industry became more evident. There are major environmental benefits in increasing the rate of development of the municipal water and sewage grid. It is mainly the Water Services Act, section 6 in particular, which is the main challenge for achieving a more efficient expansion of the water and sewage grid, both in terms of resources and time. It may require organizational change at the regime level, this in order to handle several projects simultaneously, or to provide increased support for private initiatives similar to the Aspvik project.Problemställning: Hur kan Aspviksmodellen generera nytta för den traditionellt fungerande VA-branschen? Vilka är de huvudsakliga utmaningarna för regimaktörer att implementera system liknande det som härrör från Aspviksmodellen? Syfte: Studiens syfte är tvådelat. För det första ämnar vi undersöka systemuppbyggnad och entreprenörskap från grunden i ett lokalt VA- projekt och dess affärsmodell. För det andra syftar studien till att ge förståelse för hur organisationen och VA-utbyggnadsprocessen skiljer sig mellan det lokala VA-projektet och den befintliga regimen. Metod: Studien var av kvalitativ karaktär med utgångspunkt i en abduktiv ansats. Den teoretiska referensramen var baserad på vetenskapliga publikationer och böcker samt studentlitteratur. Den empiriska datainsamlingen utgjordes av insamling av primära och sekundära data, varav primärdata erhållits genom totalt 13 semistrukturerade intervjuer och sekundärdata via webbsidor, offentligt tryck (lagar och förordningar) och övriga källor. Utifrån den teoretiska referensramen och den empiriska data genomfördes en tematisk analys. Slutsats: Aspviksmodellen kan generera nytta då den bidrar med att tillhandahålla en affärsmässig strategi med ökad transparens och visualisering över vilka möjligheter branschaktörer har och vad det kan kosta. Med transparens blev rådande problem och flaskhalsar i branschen mer tydliga. Det finns stora miljömässiga fördelar med att öka utbyggnadstakten av det kommunala VA-nätet. Från regimens synvinkel är det huvudsakligen vattentjänstlagen i sig, 6 § i synnerhet som utgör en utmaning mot en effektivare utbyggnad av VA-nätet, både ekonomiskt och tidsmässigt. För att hantera det krävs någon organisatorisk förändring på regimnivå för att kunna hantera flera projekt samtidigt, alternativt att från regimens sida ge ett ökat stöd till privata initiativ i samma slag som Aspviksprojektet.
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Qvicker, Erik. "Simulering av off-grid-lösning till flytande småhus : En undersökning av möjlig självförsörjning." Thesis, Mittuniversitetet, Institutionen för kemiteknik, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:miun:diva-40402.
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Det här arbetet gjordes i samarbete med organisationen Stockholm Tiny House Expo. Syftet med arbetet var att försöka ta fram en fungerande off-grid-lösning för uppvärmning och elproduktion, för en specifik typ av småhus med två våningar. Femton småhus kommer placeras på en flytande plattform i vattnet utanför Kastellholmen i Stockholm till en utställning år 2022. Simuleringarna utfördes på ett sådant hus under premissen att en eventuell lösning skulle vara applicerbar på samtliga småhus. Det var på förhand inte givet att en fullständig lösning skulle påträffas, eller vilken metod som skulle vara mest lyckad. Off-grid-lösningen undersöktes genom simuleringar i programvaran IDA Indoor Climate and Energy. Arbetet innefattade dimensionering av husets klimatskal, värmesystem samt system för elproduktion och energilagring. Först konstruerades en enkel modell av huset. Två olika värmesystem undersöktes. Den ena modellen använde en pelletspanna för värmeproduktion och den andra modellen använde en värmepump med sjövärme som värmekälla. I båda modellerna arbetade värmeproducenterna mot en ackumulatortank, vars vatten värmdes och sedan försåg husets tre radiatorer med varmvatten. Båda modellerna använde ett kompletterande FTX-system för uppvärmning. Målet med uppvärmningen var att på årlig basis förse huset med värme motsvarande dess effektbehov, för att hålla en jämn inomhustemperatur. Båda modellerna lyckades upprätthålla en medelinnetemperatur nära förvald temperatur på 21℃ _under höst och vinter. Ingen hänsyn togs till kylning av huset vilket resulterade i att innetemperaturen steg under sommaren. För elproduktion dimensionerades en solcellsanläggning som kompletterades med energilagringskapacitet från ett solcellsbatteri. Målet var att förse huset med en elenergi motsvarande en normal årsförbrukning för hus av den storleken samt elenergi för att driva ventilationssystemets fläktar. I värmepumpmodellen behövde även värmepumpen förses med elenergi vid drift. När hänsyn togs till energibalansen under ett år kunde ingen av modellerna förses med elenergi under hela vinterhalvåret. Detta berodde på att elförbrukningen var större än vad solcellsanläggningen tillsammans med batterilager tillförde systemet under samma period. Pelletsmodellen klarade av att vara off-grid under cirka åtta månader av året, med undantag för årets två första och sista månader. Värmepumpmodellen klarade endast av att vara off-grid under vår och sommar.
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Muller, Donovan Herbert. "The use of small photovoltaic systems for the electrification of off-grid homes." Master's thesis, University of Cape Town, 1987. http://hdl.handle.net/11427/21862.
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This thesis presents a study of the technical, economic and social appropriateness of small stand-alone photovoltaic (PV) systems for meeting minimal electrical requirements in low-income off-grid households. A comprehensive review of the literature on photovoltaic technology was undertaken to identify key theoretical parameters and issues, and also to determine what the experience has been of similar applications in third world countries. Two PV systems were installed as demonstration projects: one at Uitsig near Cape Town, and the other at Omdraaisvlei in the Northern Cape. In order to monitor and evaluate the techriical performance of these systems, remote data capture units were installed for measuring appropriate parameters for analysis on typical daily, weekly and monthly bases. The degree of matching between the PV output characteristics and the battery and load demand was examined as weLl as the costs of system and component efficiencies under different operating conditions. The economic evaluation aimed to compare small PV systems with these of alternative power systems, for example petrol generators. Using a life cycle costing methodology (discounted to present value) the least-cost option for small power systems was determined under a range of financial scenarios. The social evaluation aimed at determining the impact of PV power on peoples' lifestyles. The results of the two demonstration projects have shown that photovoltaics can appropriately meet small domestic power needs in off-grid applications, providing clean, reliable, maintenance-free electricity which is far more convenient than other electricity producing technologies. Photovoltaics proved to be very much more cost effective than petrol generators, and were also found to be cheaper than coventionally used energy sources such as paraffin, candles and batteries. Both of the demonstration project households were extremely satisfied with the PV systems, which have resulted in significant improvement in quality of lifestyles. However, based on the overall performance of the systems it was recommended that more research was needed, using local conditions, and data to develop better PV system design and sizing methodologies.
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Lorenzo, Guevara Emiliano Gabriel. "Design of an Off-grid PV System for Households in Perú and Sweden." Thesis, Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-34132.
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Because of global warming and the Paris agreement from 2015, countries need to switch their energy sources into clean sources. For some countries, like Perú, electricity produced from renewable energy sources is still a new technology. Its electricity demand depends entirely on traditional hydropower and thermal plants. Despite the high solar radiation in the coast and Andes (mountain range that passes through the entire South American continent), solar electricity is not developed and it fairly reaches the 1% of the national electricity production. Sweden, similarly, also produces its highest share on electricity from hydropower. However, nuclear energy and renewables like biomass and wind cover the rest of the demand, compared to thermal plants for Perú. On the other hand, most of the poor citizens of Perú live in the Andes, especially in remote villages, disconnected from the national grid and suffering from the cold during winter. Because their energy demand is low, it is not profitable for the electrical companies to give them electricity. The Swedish population, however, has 100% access to electricity. Despite that, high prices on maintaining the connection to the electricity network, and constant failures because of bad weather (more common nowadays because of global warming), brings the idea to disconnect from the grid and produce one´s own electricity, with, for example, photovoltaic systems. These problems occur not exclusively in Sweden. The work done on this thesis consists on a design of an off-grid solar PV system using batteries for energy storage, both for a remote farmer village in the high Andes in Perú (Ungalluta 2) and for a rural, low populated village in the center of Sweden (Gåsborn). The design is done manually and by software (PVSyst), with real life components, analyzing costs and the possibility to live entirely on solar power. The priority when choosing the components is the lowest price. For Ungalluta 2, with a demand of 17.1kWh/d (11 people), 13 PV modules and 1600Ah of battery capacity (Lead Acid) are needed, with a payback in approximately 40 years, renewing the PV panels on year 25 because of degradation. The initial investment is 21540EUR. For Gåsborn, with a demand of 36.44kWh/d (average Swedish family with children), 42 PV modules and 2850Ah of battery capacity (Lithium) are needed, with a negative payback, even increasing the PV modules to cover the entire year (more than 400). This is because the solar irradiation is quite low during winter and the load demand needs to be satisfied with considerable amounts of Diesel with a backup generator. After analyzing the results, it is possible and viable to build PV systems for the villagers in the Andes of Perú, but they will need monetary help of the government (high initial cost). For Sweden, it is not profitable to depend entirely on PV power. Other renewable sources must complement it, such as wind, to compensate the low solar irradiation and reduce the diesel consumption.På grund av global uppvärmning och Parisavtalet från 2015, måste länderna byta sina energikällor till förnybara alternativ. För vissa länder, som Perú, är el från förnybara källor fortfarande en ny teknik. Dess elbehov beror helt och hållet på traditionella vattenkraftverk och termiska anläggningar. Trots den höga solinstrålningen vid kusten och i Anderna (bergskedja som går genom hela den sydamerikanska kontinenten) är el från PV inte utvecklad och den täcker knappt 1 % av den nationella elproduktionen. Sverige producerar på motsvarande sätt sin högsta andel av el från vattenkraftverk. Den resterande delen av elbehoven täcks av kärnkraftverk och förnybar energi som biomassa och vindkraft jämfört med de termiska anläggningarna i Perú. De flesta fattiga invånarna i Perú bor i Anderna, särskilt i avlägsna byar, bortkopplade från det nationella elnätet och blir således lidande under de kalla vintrarna. På grund av deras låga energibehov är det inte lönsamt för elföretag att förse dem med elektricitet. I Sverige är det dock annorlunda. Befolkningen har 100 % tillgång till elektricitet. Trots det är priserna för underhåll av anslutning till elnäten höga och återkommande strömavbrott på grund av dåligt väder är vanligt, särskilt på landsbygden. Detta ger upphov till idén om att koppla bort från nätet och producera egen elektricitet med exempelvis solcellssystem. Arbetet i denna uppsats består av en konstruktion av ett off-Grid system med solceller som använder batterier för energilagring, både för en by högt upp i Anderna i Perú (Ungalluta 2) och för en mindre befolkad by på landsbygden i mitten av Sverige (Gåsborn). Systemen är beräknade både för hand och med mjukvara (PVSyst) med verkliga komponenter för att analysera kostnaden och möjligheten att helt och hållet leva på solenergi. Vid val av komponenterna har lägsta pris varit en prioritering. För Ungalluta 2, med ett behov på 17.1 kWh/d (11 personer), behövs 13 solcellsmoduler och en batterikapacitet på 1600Ah (Bly-syra). Den ursprungliga investeringen uppgår till 21540 EUR och återbetalningstiden till 40 år där modulerna byts ut efter 25 år på grund av degradation. För Gåsborn, med ett behov på 36.44 kWh/d (genomsnittet for en Svensk familj med barn), behövs 42 solcellsmoduler och en batterikapacitet på 2850Ah (Litium) vilket ger en negativ återbetalning även om solcellsarean ökas för att täcka hela året (mer än 400 solcellsmoduler). Detta beror på att solinstrålningen är låg under vintern och att behovet måste täckas med stora mängder diesel och med en backupgenerator. Efter att ha analyserat resultatet är det möjligt och genomförbart att bygga solcellssystem för de byborna i Anderna i Perú men de kommer att behöva kapital från regeringen (hög initial kostnad). För Sverige, är det varken lönsamt eller miljövänligt att vara helt beroende på solenergi utan andra förnybara källor så som vind måste komplettera den för att kompensera den låga solinstrålningen och för att reducera dieselförbrukningen.
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Hermansson, Caroline, and Karolina Bergkvist. "Är off-grid framtiden för det svenska elsystemet? : En analys utifrån Flernivå-perspektivet." Thesis, Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-44818.
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Syftet med detta examensarbete är att studera om scenariot off-grid är en potentiell riktning i framtidens svenska energilandskap, samt undersöka vad som kan driva en sådan utveckling. För detta examensarbete har en kvalitativ forskningsstrategi tillämpats, genom ett abduktivt förhållningssätt till funnen empiri och teori. En empirisk datainsamling har genomförts i form av semistrukturerade intervjuer med ett tiotal aktörer på den svenska elnätsmarknaden. Därefter har en tematisk analys utförts, där det empiriska materialet ställts mot teori. Studien påvisar att det idag finns flertalet faktorer som kan vara drivande för en utveckling mot ett off-grid elsystem. I studiens empiriska material går det att finna tecken på att flertalet informanter tror att en förändring av dagens svenska elsystem behövs. Dock hur troligt det är, att en sådan förändringsprocess sker, finner studien inga belägg eller grunder för. De faktorer som skulle driva utvecklingen mot ett elsystem som karaktäriseras som off-grid kan identifieras som prisutveckling, utveckling i andra sektorer, ändrad tariffsättning, decentralisering, lagstiftning, ökad popularitet samt exempel där off-grid har realiserats.The purpose of this master thesis is to study whether the off- grid scenario is a potential direction in the Swedish energy landscape of the future, and to investigate what can drive such development. For this master thesis, a qualitative research strategy has been applied, through an abductive approach towards the found empirical material and theory. An empirical data collection has been carried out in the form of semi-structured interviews with ten actors in the Swedish electricity grid market. Subsequently, a thematic analysis has been carried out, in which the empirical material is set against the theory. The study shows that there today are several factors that can drive the development towards an off-grid electricity system in Sweden. In the study’s empirical material, it is possible to find signs that most informants believe that change in today’sSwedish electricity system is needed. However, how likely it is that such a change process will take place, the study finds no evidence for. The factors that would drive the development towards an electricity system characterized by off-grid can be identified as price development, development in other sectors, changed tariff set, decentralization, legislation, increased popularity and examples where off-grid has been realized.
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Cader, Catherina [Verfasser]. "Comparison of Off-Grid Electrification versus Grid Extension: : Influencing Parameters and the Role of Renewable Energy from a Geographic Point of View / Catherina Cader." Aachen : Shaker, 2018. http://d-nb.info/118854831X/34.
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Cader, Catherina C. [Verfasser]. "Comparison of Off-Grid Electrification versus Grid Extension: : Influencing Parameters and the Role of Renewable Energy from a Geographic Point of View / Catherina Cader." Aachen : Shaker, 2018. http://nbn-resolving.de/urn:nbn:de:101:1-2019061605242126212201.
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Wernius, Emma, Hanna Olausson, and Martina Sekkenes. "Optimization of a solar water pumping system in Progreso, Amazonas, Colombia : Minor field study." Thesis, KTH, Hållbar utveckling, miljövetenskap och teknik, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-256038.
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In the villages along the Amazon river, the access to clean drinking water is lacking. In Progreso, the Swedish foundation Ankarstiftelsen and the non-governmental organization Entropika have installed a water purification system to solve this problem. The water used in the purification system is today pumped from a tributary to the Amazon river with a gasoline pump. This comes with social, ecologic and economic problems. To solve these problems, a solar water pumping system has been developed. After a preparing literature study on the topic, a field study was done to find relevant data. From this, an Excel program was made to optimize a suitable solution. Together with suggestions from three companies, two with a surface pump and one with a submersible pump, the system including a submersible pump was considered the most preferable. This mainly due to lower cost, weight and maintenance. Further, the suggestions were used to control the accuracy of the developed Excel program. This program can be used for future optimizations of systems with similar character.I byarna längs Amazonfloden är tillgången till rent dricksvatten bristfällig. Organisationerna Ankarstiftelsen och Entropika är verksamma i området och arbetar för en ökad levnadsstandard åt lokalbefolkningen. I byn Progreso har organisationerna installerat ett vattenreningssystem för att lösa problemet. Systemet använder flodvatten som renas med sandfilter och sedimentering. Vattnet pumpas idag från en biflod till Amazonfloden med en bensindriven pump. Pumpen är mycket stöldbegärlig och måste därför bäras ner till floden vid varje användning. Den väger 70 kg och utgör en arbetsbörda för vattenmästaren i byn. Utöver det är regelbundna kostanden för drivmedlet ett problem då invånarna saknar en stabil inkomst. Dessutom orsakar den bensindrivna pumpen miljöfarliga utsläpp. För att lösa de sociala, ekonomiska och ekologiska bristerna har ett solvattenpumpssystem dimensionerats. Efter en förberedande litteraturstudie inom ämnet utfördes en fältstudie i Progreso för att hitta relevanta data. Fältstudien bestod av distansmätningar och intervjuer med invånarna. Intervjuerna gav svar på huruvida dagens system fungerar samt det önskade vattenbehovet från det nya systemet. Med funna data kunde beräkningar utföras och ett Excelprogram utvecklas för att optimera ett för platsen passande system. Från tre systemförslag framtagna av företag, två förslag med ytpump och ett med en dränkbar pump, togs beslutet att den dränkbara pumpen var att föredra. Detta främst på grund av lägre kostnad, vikt och underhåll. Vidare användes förslagen för att undersöka pålitligheten hos Excelprogrammet som ämnar till att används för framtida system av liknande karaktär.