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Hållbar energi till mobila hem vintertid : Ett koncept för hållbar energiutvinning, utvald med analytisk metodik / Sustainable energy for recreational vehicles during winter season : A product development process with an analytical concept selectionDeljerud, Hampus January 2021 (has links)
Detta projekt har utförts som examinerande moment i kursen: examensarbete för högskoleingenjörsexamen i innovationsteknik och design, MSGC12, 22,5 hp. Projektet inleddes och utfördes av Hampus Deljerud med hjälp av Invencon AB. Handledare på universitetet var Monica Jakobsson, och examinator i kursen var professor Leo de Vin. Ett problem har identifierats att ägare av fritidsfordon har svårt att tillgodose sitt behov av hushållsel under vintern. Under projektet har en rad marknadsundersökningar genomförts där behovet och existerande lösningar har undersökts. Enkäter och andra undersökningsmetoder resulterade i att över hundra respondenter tog sin tid och visade intresse för att svara på frågor och delta i omröstningar. När problemet hade fastställts gjordes en projektplan för att klargöra mål, avgränsningar, milstolpar och deadlines. Detta kompletterades även med riskanalyser i försök att eliminera eventuella fallgropar. Utifrån litteraturstudier och marknadsundersökningar sammanställdes alla krav i en kravspecifikation. Kravspecifikationen användes för att se till att alla nya koncept uppfyllde alla krav. Idégenereringar utfördes digitalt med hjälp av tre olika grupper över videosamtal. Alla deltagare fick möjlighet att dela sina tankar och idéer direkt över nätet via Google drive. Tjugoen koncept togs fram och sållades ned till fem potentiella lösningar som tillgodosåg de krav som ställdes i kravspecifikationen. Ett Exceldokument togs fram där väderdata från SMHI användes i en beräkningskalkyl för att hitta den bästa lösningen på grundproblemet. Den bästa lösningen visade sig vara en kombination av energisystem där en del av systemet består av ett hopfällbart vindkraftverk. Vindkraftverkets fällmekanism tar hjälp av generatorn i kraftverket och vajrar. Genom tillämpning av existerande mekanik i dagens vindkraftverk görs konstruktionen med färre delar och resulterar i en lösning som bedöms vara gynnsam ur ett ekonomiskt perspektiv.
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Analysis of on-grid and off-grid cost for rural electrification in developing countriesXu, Yang January 2018 (has links)
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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Design and development of an off-grid e-learning centre for rural communitiesSelaule, Vusimuze Edgar 01 1900 (has links)
M. Tech. (Electronic Engineering, Faculty of Engineering and Technology), Vaal University of Technology| / The lack of electricity in off-grid rural communities in South Africa (SA) and Africa as well as the budget constraints on these communities restrict these communities from connecting to any online resources (internet and e-books) for educational purposes, thus creating a major contributor to the global digital divide.
Renewable energy sources such as solar energy, wind energy and biomass were presented as potential alternatives to grid-connected electricity for remote rural locations. Solar energy was identified as the amply available alternative energy resource in SA. Solar radiation was converted by photovoltaic technology to electricity. National power grid isolation (off-grid) was achieved by using a stand-alone photovoltaic system. Photovoltaic technology classification, material categorisation and system sizing for an e-learning centre was presented. Practical set-ups were utilised to determine the most cost-effective equipment mix of power utilization, power management/storage and ICT equipment to build a pilot e-learning centre.
It was established that one photovoltaic panel can be employed to fully recharge a battery of a pilot e-learning centre with an operational period of 7 hours using the available sunlight hours. Owing to the susceptibility of the Vaal Triangle region to thunderstorms causing overcast conditions for days, a ratio of back-up battery capacity (Ah) to number of days (seven hours per day) without sunlight was determined. An algorithm was also derived for sizing the pilot e-learning centre for full scale implementation.
Future research recommendations based on this study for a reduced system costs of an off-grid e-learning for rural communities powered by a renewable energy resource were presented. This will increase access to basic education in SA and reduce the global digital divide.
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Cost comparison of solar home systems and PV micro-grid : The influence of inter-class diversityKronebrant, Mattias January 2017 (has links)
Nearly one fifth of the global population lacks access to electricity and electricity access is essential for economic growth and human well-being. SHSs and micro-grids both have the possibility of increasing the electricity access in developing countries. The decision to choose either SHSs or micro-grids for rural electrification is a complex task that must consider both the technological factors that separate these two systems and the non-technological factors. Separate times of peak load between households (inter-class diversity) has shown to be one major advantage for the use of micro-grids. Studies have shown that the diversity factor present in micro-grids can scale down the necessary capacity of PV modules and energy storage of up to 80%, in comparison to stand-alone systems (e.g. SHSs). These reductions are nevertheless based on assumed diversity factors, not using real load profiles and the necessary capacities are calculated using intuitive methods (known to be inexact). From interviews in a rural community of Nicaragua, the author generated load profiles and determined the diversity factor of the community. The load profiles were generated with a specially designed software to formulate realistic load profiles for off-grid consumers in rural areas. These load profiles were later used in the software HOMER where the diversity’s influence on required capacity and NPC were determined by comparing SHSs to a PV based micro-grid. The study showed that the required capacity and NPC of the inverter and charge controller are clearly decreased as an influence of inter-class diversity. The required PV and battery capacity are also decreased when a micro-grid is utilized, but these reductions are most likely a result from the limited nominal power per component considered in HOMER. / Nästan en femtedel av världens befolkning saknar tillgång till elektricitet. Nicaragua är ett av de länder där en stor del av befolkningen saknar eltillgång och det gäller speciellt hushållen på landsbygden. Utbyggnader av elnätet till dessa områden är ofta låg-prioriterade på grund av höga kostnader för att tillgodose ett många gånger lågt energi och effektbehov. En alternativ lösning för att ge dessa hushåll tillgång till elektricitet är att använda off-grid system, system frikopplade från det nationella elnätet. Två vanligt förekommande off-grid system är solar home systems (SHSs) och micro-grids. Det faktum att flera hushåll ofta använder sin toppeffekt vid olika tillfällen (sammanlagring av effekt) har visat sig vara till stor fördel för micro-grids. Tidigare studier har visat att sammanlagringsfaktorn i ett micro-grid kan reducera nödvändig kapacitet av solceller och energilager upp till 80%, i jämförelse med enskilda system (t.ex. SHSs). Dessa studier bygger dock på antagna sammanlagringsfaktorer, overkliga lastprofiler och nödvändig kapacitet beräknas med intuitiva metoder. Med data från intervjuer i ett landsbygdssamhälle i Nicaragua skapas lastprofiler och en sammanlagringsfaktor beräknas för samhället. Lastprofilerna skapas i en programvara utvecklad för att formulera realistiska lastprofiler för off-grid konsumenter i landsbygdsområden. Lastprofilerna används senare i programvaran HOMER där sammanlagringens påverkan på nödvändig kapacitet och kostnad undersöks genom en jämförelse mellan SHSs och ett solcellsdrivet micro-grid. Studien visar att nödvändig kapacitet och nuvärdeskostnad för växelriktare och laddningsregulator tydligt minskar till följd av sammanlagring. Nödvändig kapacitet på solceller och batterier minskar också när ett micro-grid används. Dock beror detta med stor sannolikhet inte på sammanlagring utan är ett resultat från de begränsade märkeffekter på komponenter som användes i HOMER.
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An Application of Digital Video Recording and Off-grid Technology to Burrowing Owl Conservation ResearchWilliams, Jennifer M. 08 1900 (has links)
Through this research, engineering students and conservation biologists constructed an off-grid video system for observing western burrowing owls in El Paso, Texas. The burrowing owl has a declining population and their range decreasing, driving scientists' interest to see inside the den for observing critical nesting behavior. Texas Parks and Wildlife Department (TPWD) biologists wanted videos from inside the dark, isolated hillside owl burrows. This research yielded a replicable multi-camera prototype, empowering others to explore applications of engineering and wildlife monitoring. The remote station used an off-the-shelf video recording system, solar panels, charge controller, and lead acid batteries. Four local K-12 science educators participated in system testing at Lake Ray Roberts State Park through the Research Experiences for Teachers (RET, NSF #1132585) program, as well as four undergraduate engineering students as senior design research.
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Risk-conscious design of off-grid solar energy housesHu, Huafen 16 November 2009 (has links)
Zero energy houses and (near) zero energy buildings are among the most ambitious targets of society moving towards an energy efficient built environment. The "zero" energy consumption is most often judged on a yearly basis and should thus be interpreted as yearly net zero energy. The fully self sustainable, i.e. off-grid, home poses a major challenge due to the dynamic nature of building load profiles, ambient weather condition and occupant needs. In current practice, the off-grid status is accomplishable only by relying on backup generators or utilizing a large energy storage system.
The research develops a risk based holistic system design method to guarantee a match between onsite sustainable energy generation and energy demand of systems and occupants. Energy self-sufficiency is the essential constraint that drives the design process. It starts with information collection of occupants' need in terms of life style, risk perception, and budget planning. These inputs are stated as probabilistic risk constraints that are applied during design evolution. Risk expressions are developed based on the relationships between power unavailability criteria and "damages" as perceived by occupants. A power reliability assessment algorithm is developed to aggregate the system underperformance causes and estimate all possible power availability outcomes of an off-grid house design. Based on these foundations, the design problem of an off-grid house is formulated as a stochastic programming problem with probabilistic constraints. The results show that inherent risks in weather patterns dominate the risk level of off-grid houses if current power unavailability criteria are used. It is concluded that a realistic and economic design of an off-grid house can only be achieved after an appropriate design weather file is developed for risk conscious design methods.
The second stage of the research deals with the potential risk mitigation when an intelligent energy management system is installed. A stochastic model based predictive controller is implemented to manage energy allocation to sub individual functions in the off-grid house during operation. The controller determines in real time the priority of energy consuming activities and functions. The re-evaluation of the risk indices show that the proposed controller helps occupants to reduce damages related to power unavailability, and increase thermal comfort performance of the house.
The research provides a risk oriented view on the energy self-sufficiency of off-grid solar houses. Uncertainty analysis is used to verify the match between onsite sustainable energy supply and demand under dynamic ambient conditions in a manner that reveals the risks induced by the fact that new technologies may not perform as well as expected. Furthermore, taking occupants' needs based on their risk perception as constraints in design evolution provides better guarantees for right sized system design.
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Småskalig lagring av solcellsel : En överblick över möjligheterna att lagra solcellsel i uppladdningsbara batterier och vattenmagasin.Steen Englund, Jessika January 2012 (has links)
I det här examensarbetet dimensioneras en solcellsanläggning med batteribank till fyra kolonistugor som kommer att vara bebodda under sommarhalvåret på Wij Trädgårdar i Ockelbo. Den förväntade elanvändningen beräknas för två olika brukarbeteenden. Ett brukarbeteende där hushållsapparater med höga effekter (exempelvis mikrovågsugn) förväntas ha kortare drifttider vilket resulterar i lägre krav på installerad solcellseffekt samt en mindre batteribank.För den kemiska energilagringen i en batteribank undersöks flera olika typer av uppladdningsbara batterier. AGM blyackumulatorn är det batteri som anses vara lämpligt för kemisk energilagring i solcellssystemet och som har använts vid dimensioneringen av batteribanken. Vidare undersöks möjligheterna att lagra elektricitet småskaligt genom pumpat vatten till ett vattenmagasin, som ett komplement till energilagringen i batteribanken. Genom ett vattenlagringssystem kan överskottselen från solcellerna användas för att pumpa upp vatten till ett vattenmagasin på en högre höjd och därmed lagras genom lägesenergi. När det finns ett behov av elektricitet och den lagrade energin i batteribanken inte är tillräcklig kan vattnet flöda genom en vattenturbin som genererar el till batteribanken och lasterna. Ett vattenlagringssystem kan skydda batteribanken från djupare urladdningar, vilket kan öka batteriernas livslängd i form av antalet laddningscykler, samt ta tillvara överskottselen från solcellerna i större utsträckning. Batteribanken står för en stor del av inköpskostnaden och det finns både miljömässiga och ekonomiskt starka incitament att hitta sätt att förlänga batteribankens livslängd. / In this bachelor thesis is the size of a battery bank and the demand of photovoltaic power to supply electricity to four off-grid cottages calculated, which are occupied during the summer months at Wij Trädgårdar in Ockelbo. The expected electricity demand of the households is calculated for two different user patterns. In one of the user patterns the household appliances with a high power demand (for example microwave) are expected to have a shorter daily usage time, which results in a considerable lower purchase cost as a result from lower power demand of installed photovoltaic and a smaller battery bank. For the battery bank have different rechargeable batteries been investigated. The AGM Lead-Acid battery is found to be the most suitable rechargeable battery for chemical energy storage in this photovoltaic system. Furthermore the possibilities of pumping water to a water reservoir and store as potential energy as a complement to the energy storage in the battery bank have been investigated and discussed. Through a small-scale pumped hydro storage the surplus electricity from the photovoltaic can be used to pump up water to a reservoir at a higher altitude and be stored as potential energy. When there is a demand of electricity and the energy stored in the battery bank is not enough the water can be used in a small-scale water turbine, which generates electricity t the battery bank and the loads. A pumped hydro storage can protect the battery bank from deeper discharge, which otherwise can reduce the lifetime of the batteries, and extend the number of charge and discharge cycles the batteries can manage. The battery bank represents a large part of the purchase costs and there are strong environmental and economical incentives to prolong the lifetime of the battery bank.
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Improving the sustainability of rural electrification schemes : capturing value for rural communities in UgandaHirmer, Stephanie January 2018 (has links)
This research investigates what rural villagers perceive as important and develops recommendations for improved electrification project implementation centring on user-perceived values (UPVs). UPVs capture more than the basic definition of value in the sense that they include benefits, concerns, feelings and underlying drivers that vary in importance and act as the main motivators in the lives of project beneficiaries as perceived at a given time. Low access to energy continues in rural sub-Saharan Africa despite significant investment by the development community. One fundamental reason is that energy infrastructure adoption remains low, as evidenced by the lack of project sustainability. To counter this, the challenge for energy project developers is to achieve sustainable long-term interventions through the creation of value for beneficiaries, rather than the traditional approach of focusing on short-term project outputs. The question of what is valuable to people in rural communities has historically not played into the design and diffusion of energy infrastructure development projects. This research drew on design and marketing approaches from the commercial sector to investigate the UPVs of rural Ugandans. To better understand the UPVs of rural villagers a new method, consisting of a UPV game and UPV framework, was developed. This method is suitable for capturing, understanding and mapping what rural populations perceive as important. Case study analyses were carried out in seven villages across rural Uganda. The case studies included the UPV game supplemented by non-energy-specific and energy-specific interviews with villagers. Additionally, interviews with experts were conducted to verify the UPV framework and to identify the gap between experts’ opinion and villagers’ perception of what is important. The research demonstrates the effectiveness of the UPV game in deducing the values of rural villagers. The findings demonstrate a disconnect in the ability to accurately capture and design projects which resonate with and respond to the UPVs of recipients of rural electrification projects. A comparison between the villagers’ statements and experts’ opinion regarding what is most valuable to rural communities reveals striking differences that point to a fundamental misunderstanding of rural community UPVs which are likely to be contributing to widespread electrification project failure.
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Socio-Technical Analysis for the Off-Grid PV System at Mavuno Girls’ Secondary School in TanzaniaElbana, Karim January 2018 (has links)
The aim of this study is to investigate, analyse and evaluate the installed off-grid PV system in Mavuno girls’ secondary school that is located in a rural area in northwest Tanzania. The original motivation behind this study was the rapid degradation of the installed battery bank within less than 3 years. The PV system was installed before the actual operation of the school, so the study aimed to answer a very pressing question which is "What is the actual load profiles in the school?". There was a high need to identify the actual school load profiles to enable several concerned social actors to evaluate the system and to decide for future extensions. Therefore, the study aimed to analyse the implementation of electricity in the school by creating actual load profiles, analysing the system performance versus the users’ needs and evaluating the sustainability and utilization of implementation. The study followed a multi-disciplinary approach combining the social and technical aspects of PV systems implementation to seek further understanding of the users’ consumption behaviours. It thus included a 1-month of field work in June 2018 during which participant observations and semi-structured interviews together with load measurements were carried out so as to create load profiles that are considering the patterns and deviations in users’ behaviours. During the field work, 2/3 of the students were in holidays so the taken measurements corresponded to the school at 30 % capacity. That is why the study also included 4 days of inverter data logging after the 1-month field work by the technical head of the school to overcome the limitations in held measurements. The observations showed that the actual installed system was slightly different from the documentation. In addition, the local installation practices are not fully appropriate from the technical point of view, and are affected by local social norms, as will be discussed. Besides, the participant observations and held interviews with relevant social actors showed that the daily behaviours of energy users do not exactly follow the school daily routine. Consequently, the social study was important to create actual effective load profiles. The observations and responses from interviews together with measurements were used to categorize the school loads into 29 different units. Those units can be used for current load prioritizations and for future load extrapolations. The created load profiles also represent a useful addition to load databases used by energy researchers who work on similar rural electrification projects. After the field work, several characteristics were calculated by Microsoft Excel such as apparent power consumptions, active power consumptions, battery bank state of charge, load power factor and PV generated energy. The characteristics were used in calculations evaluating the energy balance in the system. The results of held calculations showed that lighting during dark hours accounted for on around 78 % of the logged daily apparent energy use, as it has a low a low average power factor of 0.28. It also showed that some loads if time-bounded, they will significantly decrease the daily energy consumption. The calculations were also used to run PVSyst simulations to evaluate the system sizing which resulted in the recommendation that either the array size should be doubled, or the apparent energy consumption should be decreased to half. The study included suggestions for possible improvements such as decreasing the reactive consumed energy by either replacing the currently used light bulbs with ones that have higher power factor ( ≥0.8 for example) or by installing a capacitive compensation for power factor correction. In addition, it was recommended to quantify the school loads according to their priority or importance and to regulate observed time-unbounded loads such as "pumping water" and "ironing". Lastly, the study discussed how generated electricity is utilized in the school and what opportunities for women empowerment have become potentially possible with the provision of electricity.
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An iterative analytical design framework for the optimal designing of an off-grid renewable energy based hybrid smart micro-grid : a case study in a remote area - JordanHalawani, Mohanad January 2015 (has links)
Creative ways of utilising renewable energy sources in electricity generation especially in remote areas and particularly in countries depending on imported energy, while increasing energy security and reducing cost of such isolated off-grid systems, is becoming an urgently needed necessity for the effective strategic planning of Energy Systems. The aim of this research project was to design and implement a new decision support framework for the optimal design of hybrid micro grids considering different types of different technologies, where the design objective is to minimize the total cost of the hybrid micro grid while at the same time satisfying the required electric demand. Results of a comprehensive literature review, of existing analytical, decision support tools and literature on HPS, has identified the gaps and the necessary conceptual parts of an analytical decision support framework. As a result this research proposes and reports an Iterative Analytical Design Framework (IADF) and its implementation for the optimal design of an Off-grid renewable energy based hybrid smart micro-grid (OGREH-SμG) with intra and inter-grid (μG2μG & μG2G) synchronization capabilities and a novel storage technique. The modelling design and simulations were based on simulations conducted using HOMER Energy and MatLab/SIMULINK, Energy Planning and Design software platforms. The design, experimental proof of concept, verification and simulation of a new storage concept incorporating Hydrogen Peroxide (H2O2) fuel cell is also reported. The implementation of the smart components consisting Raspberry Pi that is devised and programmed for the semi-smart energy management framework (a novel control strategy, including synchronization capabilities) of the OGREH-SμG are also detailed and reported. The hybrid μG was designed and implemented as a case study for the Bayir/Jordan area. This research has provided an alternative decision support tool to solve Renewable Energy Integration for the optimal number, type and size of components to configure the hybrid μG. In addition this research has formulated and reported a linear cost function to mathematically verify computer based simulations and fine tune the solutions in the iterative framework and concluded that such solutions converge to a correct optimal approximation when considering the properties of the problem. As a result of this investigation it has been demonstrated that, the implemented and reported OGREH-SμG design incorporates wind and sun powered generation complemented with batteries, two fuel cell units and a diesel generator is a unique approach to Utilizing indigenous renewable energy with a capability of being able to synchronize with other μ-grids is the most effective and optimal way of electrifying developing countries with fewer resources in a sustainable way, with minimum impact on the environment while also achieving reductions in GHG. The dissertation concludes with suggested extensions to this work in the future.
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