Dissertations / Theses: 'Solar energy Solar energy in agriculture'

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Dos, Santos Charline Ninon Lolita. "Agrivoltaic system : A possible synergy between agriculture and solar energy." Thesis, KTH, Kraft- och värmeteknologi, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-272965.

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The development of photovoltaic energy requires a lot of land. To maximize the land use, agrivoltaic systems that combine an agricultural and an electrical production on the same land unit are developed. A demonstrator was built in Montpellier (France) with dierent experimental arrangements to study the impact of a xed and a dynamic solutions on the crops below the panels. The eect of shade on lettuces appears to be positive with a Land Equivalent Ratio greater than 1. To extend the experiment to other crops, the crop species best adapted to the agrivoltaic system are identied. The shade tolerance and vulnerability to climate change are key parameters to select crops that will benet the most from the installation of PV panels. The SWOT analysis brings out that agrivoltaic systems can be a solution to maximize the land use and to adapt crops to climate change. The technical constraints imposed by the PV structure must be overcome to deploy this technology on a large scale. The greatest threat lies in the non-acceptability of the projects by farmers and the chambers of agriculture. An agrivoltaic project was developed in the South of France as a rst testing area but was nally abandoned because of too important reciprocal constraints for the farmer and the operator.
Utvecklingen av fotovoltaisk energi kräver mycket mark. För att maximera markanvändningen utvecklas agrivoltaiska system som kombinerar en jordbruksproduktion och en elektrisk produktion på samma markenhet. En demonstrant byggdes i Montpellier (Frankrike) med olika experimentella arrangemang för att studera effekterna av en fast och en dynamisk lösning på grödorna under panelerna. Effekten av skugga på sallader verkar vara positiv med en LER som är större än 1. För att utvidga experimentet till andra grödor identiferas de grödor som bäst anpassas till det agrivoltaiska systemet. Skuggtoleransen och sårbarheten för klimatförändringar är viktiga parametrar för att välja grödor som kommer att dra mest nytta av installationen av PV-paneler. SWOT-analysen visar att agrivoltaiska system kan vara en lösning för att maximera markanvändningen och anpassa grödorna till klimatförändringar. De tekniska begränsningarna som PV-strukturen sätter måste övervinnas för att kunna använda denna teknik i stor skala. Det största hotet ligger i att projekten inte godtas av jordbrukare och jordbrukskamrar. Ett agrivoltaiskt projekt utvecklades i södra Frankrike som ett första testområde men övergavs slutligen på grund av för viktiga ömsesidiga begränsningar för bonden och operatören.

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Bezerra, Pedro Henrique Silva 1988. "Energia solar concentrada : simulação do desempenho de heliostatos de pequeno porte /." Botucatu, 2017. http://hdl.handle.net/11449/152845.

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Orientador: Odivaldo José Seraphim
Coorientador: Celso Eduardo Lins de Oliveira
Banca: Celso da Costa Carrer
Banca: Luis Roberto Almeida Gabriel Filho
Banca: Luiz Antonio Rossi
Banca: Alexandre Dal Pai
Resumo: A pesquisa apresentada nessa tese foi estruturada em quatro capítulos. O capítulo 1 apresenta, de forma introdutória, o estudo da arte da tecnologia CSP no mundo, bem como os conceitos tecnológicos e princípios físicos de funcionamento. Mais além, demonstrar o potencial solar brasileiro do ponto de vista exploratório. O capítulo 2, apresenta uma previsão de performance e rendimento energético de um sistema CSP com torre central integrado a atividades agroindustriais no Brasil, por meio de uma simulação transiente. O capítulo 3, apresenta de forma detalhada a adaptação e aplicação de uma análise paramétrica para determinação do custo mínimo por unidade de área de heliostato, o custo mínimo do primeiro heliostato produzido no Brasil, como também o custo nivelado da eletricidade gerada. No capítulo 4, foi apresentado um estudo do marco legal jurídico regulatório para sistemas CSP com torre central: geração e comercialização de energia elétrica de fonte solar no brasil. Por fim, foram apresentadas perspectivas de novas pesquisas a serem realizadas e as considerações finais.
Abstract: The search for new energy sources has been driven by an international standard that limits the emission of atmospheric pollutants. The establishment of renewable energy generation technologies will consolidate the future of sustainable development. The new technologies promise to economic opportunities and social benefits to remote places of the world, or where energy is scarce. Among the new sources or alternative sources of energy, solar is the most promising in terms of availability and well accepted by popular opinion. Historically, the sun's energy is being harnessed in different productive sectors and several countries. Furthermore, the concentrated solar power (CSP) runs through well-defined and known methods, based on well-established physical principles of engineering and using available materials and conventional. In order to present the theoretical conceptions of the operation of CSP technology, the objective of this chapter was to develop the current state of the art of technology and to correlate with the brazilian...
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Tanaka, Adriana Aki [UNESP]. "Avaliação de métodos de estimativa da radiação solar global e da evapotranspiração de referência para o estado de Mato Grosso." Universidade Estadual Paulista (UNESP), 2013. http://hdl.handle.net/11449/103458.

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A radiação solar é fonte de energia nos processos físicos, químicos e biológicos que ocorrem na superfície terrestre e é o principal elemento climático que interfere na evapotranspiração das culturas, pois interfere no processo fotossintético destas. Por isso quando não se dispõe de dados medidos de evapotranspiração de referência, pode-se usar métodos de estimativa para tal quantificação. Este trabalho foi dividido em três capítulos e teve por objetivo geral avaliar o desempenho de modelos simplificados de estimativa da radiação solar e evapotranspiração para 28 cidades do estado de Mato Grosso. O primeiro capítulo objetivou a calibração regional e a avaliação do desempenho estatístico de quinze modelos simplificados de estimativa da radiação global baseados na temperatura do ar. Os dados foram fornecidos pelo Instituto Nacional de Meteorologia (INMET), coletados por estações meteorológicas automáticas (EMA’s) localizadas nas cidades de Água Boa, Alta Floresta, Apiacás, Campo Novo do Parecis, Campo Verde, Carlinda, Comodoro, Confresa, Cotriguaçu, Cuiabá, Gaúcha do Norte, Guarantã, Guiratinga, Itiquira, Juara, Juína, Nova Maringá, Nova Ubiratã, Novo Mundo, Pontes e Lacerda, Porto Estrela, Rondonópolis, Salto do Céu, Santo Antônio do Leste, São Félix do Araguaia, Sinop, Sorriso e Vila Bela da Santíssima Trindade. Os modelos calibradas foram: Abraha e Savage; Abraha e Savage Weiss; Almorox; Annandele; Bristow e Campbell; Chen; De Jong e Stewart; Donatelli e Campbell; Goodin; Hargreaves; Hunt (dois coeficientes); Hunt (quatro coeficientes); Mahmood e Hubbard; Meza e Varas e Thorton e Running. Os índices de desempenho utilizados foram o coeficiente de determinação da regressão linear (R2), o Erro Médio Relativo (EMR), a Raiz Quadrada do Quadrado Médio do Erro (RQME) e o índice d de Willmott. Os valores de R2 variaram de 0,40 a 0,70 e a RQME foi, em...
A radiação solar é fonte de energia nos processos físicos, químicos e biológicos que ocorrem na superfície terrestre e é o principal elemento climático que interfere na evapotranspiração das culturas, pois interfere no processo fotossintético destas. Por isso quando não se dispõe de dados medidos de evapotranspiração de referência, pode-se usar métodos de estimativa para tal quantificação. Este trabalho foi dividido em três capítulos e teve por objetivo geral avaliar o desempenho de modelos simplificados de estimativa da radiação solar e evapotranspiração para 28 cidades do estado de Mato Grosso. O primeiro capítulo objetivou a calibração regional e a avaliação do desempenho estatístico de quinze modelos simplificados de estimativa da radiação global baseados na temperatura do ar. Os dados foram fornecidos pelo Instituto Nacional de Meteorologia (INMET), coletados por estações meteorológicas automáticas (EMA’s) localizadas nas cidades de Água Boa, Alta Floresta, Apiacás, Campo Novo do Parecis, Campo Verde, Carlinda, Comodoro, Confresa, Cotriguaçu, Cuiabá, Gaúcha do Norte, Guarantã, Guiratinga, Itiquira, Juara, Juína, Nova Maringá, Nova Ubiratã, Novo Mundo, Pontes e Lacerda, Porto Estrela, Rondonópolis, Salto do Céu, Santo Antônio do Leste, São Félix do Araguaia, Sinop, Sorriso e Vila Bela da Santíssima Trindade. Os modelos calibradas foram: Abraha e Savage; Abraha e Savage Weiss; Almorox; Annandele; Bristow e Campbell; Chen; De Jong e Stewart; Donatelli e Campbell; Goodin; Hargreaves; Hunt (dois coeficientes); Hunt (quatro coeficientes); Mahmood e Hubbard; Meza e Varas e Thorton e Running. Os índices de desempenho utilizados foram o coeficiente de determinação da regressão linear (R2), o Erro Médio Relativo (EMR), a Raiz Quadrada do Quadrado Médio do Erro (RQME) e o índice d de Willmott. Os valores de R2 variaram de 0,40 a 0,70 e ...

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Tanaka, Adriana Aki 1983. "Avaliação de métodos de estimativa da radiação solar global e da evapotranspiração de referência para o estado de Mato Grosso /." Botucatu:, 2013. http://hdl.handle.net/11449/103458.

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Orientador: Antonio Evaldo Klar
Banca: João Carlos Cury Saad
Banca: Roberto Angelocci
Banca: Altair Bertonha
Banca: Adilson Pacheco de Souza
Resumo: A radiação solar é fonte de energia nos processos físicos, químicos e biológicos que ocorrem na superfície terrestre e é o principal elemento climático que interfere na evapotranspiração das culturas, pois interfere no processo fotossintético destas. Por isso quando não se dispõe de dados medidos de evapotranspiração de referência, pode-se usar métodos de estimativa para tal quantificação. Este trabalho foi dividido em três capítulos e teve por objetivo geral avaliar o desempenho de modelos simplificados de estimativa da radiação solar e evapotranspiração para 28 cidades do estado de Mato Grosso. O primeiro capítulo objetivou a calibração regional e a avaliação do desempenho estatístico de quinze modelos simplificados de estimativa da radiação global baseados na temperatura do ar. Os dados foram fornecidos pelo Instituto Nacional de Meteorologia (INMET), coletados por estações meteorológicas automáticas (EMA's) localizadas nas cidades de Água Boa, Alta Floresta, Apiacás, Campo Novo do Parecis, Campo Verde, Carlinda, Comodoro, Confresa, Cotriguaçu, Cuiabá, Gaúcha do Norte, Guarantã, Guiratinga, Itiquira, Juara, Juína, Nova Maringá, Nova Ubiratã, Novo Mundo, Pontes e Lacerda, Porto Estrela, Rondonópolis, Salto do Céu, Santo Antônio do Leste, São Félix do Araguaia, Sinop, Sorriso e Vila Bela da Santíssima Trindade. Os modelos calibradas foram: Abraha e Savage; Abraha e Savage Weiss; Almorox; Annandele; Bristow e Campbell; Chen; De Jong e Stewart; Donatelli e Campbell; Goodin; Hargreaves; Hunt (dois coeficientes); Hunt (quatro coeficientes); Mahmood e Hubbard; Meza e Varas e Thorton e Running. Os índices de desempenho utilizados foram o coeficiente de determinação da regressão linear (R2), o Erro Médio Relativo (EMR), a Raiz Quadrada do Quadrado Médio do Erro (RQME) e o índice d de Willmott. Os valores de R2 variaram de 0,40 a 0,70 e a RQME foi, em ...
Abstract: A radiação solar é fonte de energia nos processos físicos, químicos e biológicos que ocorrem na superfície terrestre e é o principal elemento climático que interfere na evapotranspiração das culturas, pois interfere no processo fotossintético destas. Por isso quando não se dispõe de dados medidos de evapotranspiração de referência, pode-se usar métodos de estimativa para tal quantificação. Este trabalho foi dividido em três capítulos e teve por objetivo geral avaliar o desempenho de modelos simplificados de estimativa da radiação solar e evapotranspiração para 28 cidades do estado de Mato Grosso. O primeiro capítulo objetivou a calibração regional e a avaliação do desempenho estatístico de quinze modelos simplificados de estimativa da radiação global baseados na temperatura do ar. Os dados foram fornecidos pelo Instituto Nacional de Meteorologia (INMET), coletados por estações meteorológicas automáticas (EMA's) localizadas nas cidades de Água Boa, Alta Floresta, Apiacás, Campo Novo do Parecis, Campo Verde, Carlinda, Comodoro, Confresa, Cotriguaçu, Cuiabá, Gaúcha do Norte, Guarantã, Guiratinga, Itiquira, Juara, Juína, Nova Maringá, Nova Ubiratã, Novo Mundo, Pontes e Lacerda, Porto Estrela, Rondonópolis, Salto do Céu, Santo Antônio do Leste, São Félix do Araguaia, Sinop, Sorriso e Vila Bela da Santíssima Trindade. Os modelos calibradas foram: Abraha e Savage; Abraha e Savage Weiss; Almorox; Annandele; Bristow e Campbell; Chen; De Jong e Stewart; Donatelli e Campbell; Goodin; Hargreaves; Hunt (dois coeficientes); Hunt (quatro coeficientes); Mahmood e Hubbard; Meza e Varas e Thorton e Running. Os índices de desempenho utilizados foram o coeficiente de determinação da regressão linear (R2), o Erro Médio Relativo (EMR), a Raiz Quadrada do Quadrado Médio do Erro (RQME) e o índice d de Willmott. Os valores de R2 variaram de 0,40 a 0,70 e ...
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Carvalho, Pedro Miguel Lavareda. "Zero energy. A energia solar como veículo para a sustentabilidade e rentabilidade de uma exploração agricola." Master's thesis, ISA, 2010. http://hdl.handle.net/10400.5/3361.

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Mestrado em Engenharia do Ambiente - Tecnologias Ambientais - Instituto Superior de Agronomia
In a world where the problems and concerns over the environment are growing, mainly associated to the GHG emissions, taking more sustainable behaviors it’s imperative in all business sectors. Throughout its history, agriculture has become technologically modern in order to be able to meet the food needs of an increasingly large and consumerist population, and at the same time, staying profitable in an increasingly competitive market. This trend of technological change has also occurred in renewable energy, particularly solar energy. This work aimed to demonstrate the opportunity, necessity and importance of adopting an agriculture vision, which promotes a more sustainable development through the implementation of several technologies for harnessing solar energy on a farm, increasing its cost-effectiveness too. The adopted approach consisted on energy consumption analysis (electricity and heat) of a prototype farm, based on real data from two types of farming (livestock and horticulture), which were subsequently implemented several technologies for harnessing solar energy (solar photovoltaic, solar thermal and solar passive), making the operation environmentally more sustainable by reducing the use and the dependence of fossil fuels, and economically more viable, with reduced consumption and direct sales of energy produced to the electric grid. Based on the collected information on the ground and after construction of the prototype, where some energy consumption process were added, aimed to include greater representation at national level, were evaluated various possibilities of using solar energy in the prototype, implementation, cost / benefit and environmental sustainability, using tree international computational software’s (PVsyst, Sunny Design and Wica). It was concluded that the Solar Energy and Agriculture could and should have a Convergent Future!

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Jorns, Austin R. "Smallholder farmers’ perceptions toward solar renewable energy technology on the island of Trinidad." The Ohio State University, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=osu1587714750296474.

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Santos, Breno Monteiro dos. "Metodologia de dimensionamento de sistemas de aquecimento solar para secagem de produtos agricolas." [s.n.], 2004. http://repositorio.unicamp.br/jspui/handle/REPOSIP/257240.

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Orientadores: Marlene Rita de Queiroz, Thomaz Penteado de Freitas Borges
Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Agricola
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Resumo: Uma metodologia para o projeto de coletores solares visando a secagem de grãos em silo foi implementada utilizando-se correlações empíricas previamente determinadas para o cálculo da fração solar fornecida pelo sistema. Foi realizado um estudo de caso de uma secagem de milho em silo, na cidade de Campinas ¿ SP, com pré-aquecimento do ar através de um coletor solar e aquecimento complementar com fonte energética convencional (GLP ou lenha). O coletor solar utilizado possui área de 1,80m2, foi construído com materiais de baixo custo e, devido ao material constituinte de seu leito (pedras britadas), apresenta elevada inércia térmica e capacidade de armazenar energia. A caracterização do coletor foi feita com o levantamento da sua curva de eficiência e com a determinação de sua constante de tempo. De maneira semelhante ao observado em coletores solares convencionais, a curva característica levantada apresentou comportamento linear. A capacidade de armazenar energia térmica foi constatada no elevado valor da constante de tempo obtida e pelas defasagens entre as curvas de calor útil fornecido ao ar e radiação solar incidente na superfície do equipamento. Na secagem de 1,20t de milho considerada no estudo de caso, utilizando-se uma vazão volumétrica específica de ar igual a 1,20 m3/m3.min à temperatura de 50°C, obteve-se uma economia de 31% na energia demandada para o aquecimento de ar. Através da análise de ciclo de vida econômico, para a utilização conjunta de energia solar e GLP no aquecimento de ar, foi determinada uma área coletora ótima de 7,50m2 a uma taxa de interesse de 0,12a.a., proporcionando o máximo retorno financeiro durante o ciclo de vida do equipamento. Aumentos nas taxas de interesse diminuem tanto os valores de área coletora ótima como do retorno financeiro durante o ciclo de vida econômico. Foi demonstrada, para as condições fixadas no estudo de caso, a viabilidade econômica da conversão de sistemas que utilizam GLP como fonte energética para sistemas assistidos por energia solar, proporcionando redução nos impactos ambientais da atividade e economia para o produtor rural. Nas mesmas condições foi verificada a inviabilidade econômica da utilização de energia solar em conjunto com a lenha
Abstract: A solar collector design procedure was proposed for sizing solar assisted crop-drying systems using empiric correlations, previously found, to determine the solar fraction supplied by the system. A case study of an in-bin crop drying was accomplished in the city of Campinas - SP with pre-heating of the air through a solar collector complemented by conventional energy source (LPG or firewood). The used solar collector had an area of 1,80m2, it was built with low cost materials and, due to its pebble bed, it presented a high thermal inertia and storing energy capacity. The collector was characterized by determining its efficiency curve and its time constant. As observed in conventional solar collectors, the characteristic curve presented linear behavior. The capacity to store thermal energy was confirmed by the high value of the time constant and by the delay between the useful heat and the incident solar radiation curves. In the studied case of drying 1,20 tons of corn, using a specific air flow rate equal to 1,20 m3/m3.min and a temperature of 50°C, it was saved 31% of the demanded energy for air heating. For a solar-assisted drying using LPG as the conventional source of energy, an optimum collector area of 7,50m2 was found through the life cycle saving analysis calculated with an annual interest rate of 0,12, providing the maximum saves during the equipment life cycle. Increasing the interest rate reduced both optimum collector areas and life cycle savings. For the crop drying case, it was demonstrated the economical viability of the conversion of LPG based to solar-assisted systems, providing reduction in the environmental impacts of the activity and savings for the rural producer. In the same conditions was demonstrated there is no economical viability in the conversion of firewood based to solar-assisted systems
Mestrado
Tecnologia Pós-Colheita
Mestre em Engenharia Agrícola

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Al-zoheiry, Ahmed M. "Modeling a drip irrigation system powered by a renewable energy source." Columbus, Ohio : Ohio State University, 2006. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1164762929.

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Palermo, Rick. "Analysis of solar power generation on California turkey ranches." Thesis, Manhattan, Kan. : Kansas State University, 2009. http://hdl.handle.net/2097/1607.

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Al, Hodali Reyad. "Numerical simulation of an agricultural foodstuffs drying unit using solar energy and adsorption process." Doctoral thesis, Universite Libre de Bruxelles, 1997. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/212169.

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Van, Wyk Gerrit. "Sonenergie as 'n plaasvervanger vir energie uit fossielbrandstof binne die landbousektor, op klein en medium skaal in die Noord-Kaap." Thesis, Stellenbosch : Stellenbosch University, 2015. http://hdl.handle.net/10019.1/97369.

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Thesis (MBA)--Stellenbosch University, 2015.
AFRIKAANSE OPSOMMING: Elektrisiteit is ŉ basiese bron van energie in hedendaagse huishoudings en besighede. Die behoefte na deurlopende elektrisiteit neem toe terwyl die huidige elektrisiteitsverskaffer, ESKOM, ook nie aan die huidige vraag na elektrisiteit kan voorsien nie. Verdere beperkings is die infrastruktuur. Die infrastruktuur is nie so ontwikkel dat elektrisiteit aan 100 persent van die bevolking verskaf kan word nie. Alle plase het nie toegang tot die huidige ESKOM roosterstelsel nie of dit is onprakties om ŉ dienslyn te bou vir die gerief van elektrisiteit. Gevolglik was die meeste boerderybedrywighede in die verlede afhanklik van dieselkragopwekkers. Die gebruik van sonenergie het egter aantrekliker geword en het moontlik meer ekonomies en prakties geword en bied ook ŉ deurlopende krag opsie. Sonstralingsvlakke in Suid Afrika is die hoogste in die wêreld. Die Noord-Kaap word ingesluit in daardie areas in SA wat uiters geskik is vir PV aanlegte. In lande soos Ethiopië en die VSA is sonenergie met PV-tegnologie met groot sukses aangewend in landbouomstandighede vir die voorsiening van elektrisiteit wat ook in SA met sukses aangewend kan word met die uiters geskikte sonbestralingsvlakke. Die grootste voordeel van sonenergie is die oorvloedige beskikbaarheid van die energiebron in SA. Verder is dit volhoubaar, omgewingsvriendelik, hernubaar en heeltemal gratis. Daar is geen bewegende onderdele nie, gevolglik is daar geen geraasbesoedeling nie en is die bedryfskostes van ŉ sonenergie stelsel baie laag. Die nadeel van sonenergie is dat PV-aanlegte slegs elektrisiteit kan opwek wanneer die son skyn. Energiebergingsisteme is nodig om hierdie nadeel te oorbrug of ŉ aanvullende energiebron soos wind moet gebruik word om die tekort aan te vul. Kapitaalspandering is die grootste hindernis in die oprigting van hernubare energiestelsels aangesien dit op een stadium spandeer moet word. Sonenergie is die gewildste energiebron binne die landbousektor in die Noord-Kaap en word deur 88.57 persent van die respondente gebruik terwyl slegs 28.57 persent van die respondente dieselkragopwekkers beskikbaar het as rugsteun fasiliteit vir elektrisiteitvoorsiening. Die belangrikste redes waarom daar oorgeskakel is na sonenergie, was om deurlopende elektrisiteit te verseker en die vermindering van tradisionele energieverbruik. Die studie toon dat sonenergie, oor ŉ 15 jaar leeftyd, ŉ derde van die koste van fossielbrandstowwe kos, alhoewel daar groter aanvanklike kapitaalspandering betrokke is wat as ŉ struikelblok gesien word. Die statistiek wat in die ondersoek versamel is dui daarop dat sonenergie suksesvol aangewend word om te voorsien aan die elektrisiteitbehoeftes van die respondente binne die Noord-Kaap geografiese gebied. Daar is egter geen twyfel dat sonenergie suksesvol, effektief, doeltreffend en ekonomies aangewend kan word as ŉ plaasvervanger vir energie uit fossielbrandstof, binne die landbousektor, op klein en medium skaal in die Noord-Kaap.

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Choi, Chong Seok Seok. "COMBINED LAND USE OF SOLAR INFRASTRUCTURE AND AGRICULTURE FOR SOCIOECONOMIC AND ENVIRONMENTAL CO-BENEFITS IN THE TROPICS." Master's thesis, Temple University Libraries, 2019. http://cdm16002.contentdm.oclc.org/cdm/ref/collection/p245801coll10/id/546811.

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Geology
M.S.
Solar photovoltaic (PV) generation has been gaining popularity as low carbon energy technology in the face of the global climate change. However, conventional utility-scale PV requires large swaths of land to be occupied for decades which prevents the land from producing food or performing vital ecosystem services. Co-location of PV with crop cultivation is an emerging strategy for mitigating the land use of PV. In order to optimize this strategy, the impact of the plant growth-related soil properties need to be quantified. To this end, the first portion of the thesis investigated the impacts on the soil properties in a re-vegetated solar PV facility in Boulder, Colorado, which was the oldest vegetation-PV co-location site in the world. The second portion of the thesis uses a life cycle analysis (LCA) approach to test the feasibility of co-location of model crop cultivation and solar PV electricity generation in rural Indonesia, and it is the first study to use the LCA study of the co-located solar in the tropics. The first approach revealed that the soil hydrology, grain size distribution, and total carbon and nitrogen are significantly altered from their original state by the construction and presence of photovoltaic arrays, and that those properties had not been restored to their pre-construction levels despite the fact that ten years had passed since re-vegetation of the PV array. The persistence of the altered soil properties meant that the designs regarding re-vegetation or co-location of PV with crops would have to be considered at the beginning of the construction of the PV to minimize the impact on the soil and the existing vegetation. Furthermore, soil moisture was the highest in the soil underneath the western edge of the PV panels, where the western tilt of the PV panel had concentrated the rainfall. The heterogeneity in soil hydrology created by the panels could be manipulated to benefit the growth of vegetation within the PV array. The LCA approach revealed that a hectare of PV arrays with full module density would carbon offsets against diesel electricity generation and the grid, and that the annual supply of electricity from the PV could satisfy the demand of a typical rural Indonesian village several times over. However, the high capital expenditure of solar mean that co-location with full PV module density would not be economically feasible, even with the income stream from the co-located crop cultivation. In order to reduce the capital expenditure, the PV module density for co-location was reduced to half. The combination of reduced capital expenditure and the income stream from the crop made the co-located land use significantly less costly. Additionally, the rural electrification would be able to provide secondary socioeconomic benefits such as avoidance of health costs through operation of public health infrastructures, increased standard of living, and secondary income opportunities from processing of raw materials. However, better subsidies for renewables, specialized loan structures for small-scale renewable systems, and a culture of co-operation between small landholders would need to be implemented before the co-located system becomes affordable to the inhabitants in rural Indonesian villages.
Temple University--Theses

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Henriksson, Amanda, and Stina Busin. "Field study in Machacamarca, Bolivia : An investigation on the effects of implementing solar powered irrigation." Thesis, KTH, Hållbar utveckling, miljövetenskap och teknik, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-230998.

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This bachelor thesis consists of a field study conducted in the canton of Machacamarca close to La Paz in Bolivia. The global climate change has affected the weather in the area which has caused higher temperatures, irregularity in precipitation and unexpected frost. This has complicated the traditional cultivation methods and affected the harvest yield. One of the more important sources of income in the canton is the local diary that is processing milk from the local farmers. The main purpose of the thesis was to investigate the economic improvements that could be achieved in the canton with the implementation of an irrigation system driven by photovoltaic power, and to evaluate if it would be feasible. The simulation program Decision support system for agrotechnology transfer, DSSAT, has been used to simulate the cultivation and harvest of the two main crops for forage, alfalfa and barley. The required input data has been collected from the canton of Machacamarca and used to simulate the harvest yield for three scenarios, business as usual, ideal irrigation and limited irrigation calculated from the local conditions. A Matlab code based on numbers and parameters collected during the field study is used to create economical simulations from the different harvest results to receive economical results from several steps in the process. The final economical outcomes are compared to each other and to the cost for the chosen pump and irrigation system. Both scenarios considering irrigation show a stabilized and improved harvest yield, but only the third scenario is possible to implement in Machacamarca due to water restrictions in the area. This makes it possible to feed 0.47 more cows per hectare which will improve the farmers and the diary ́s income with 94.57 %. The water use for irrigation is 1.33 litres per square meter which makes the Shurflo 8000 water pump the most suitable option to provide water to the irrigation system powered by a 130 W solar panel and a battery. The investment cost for the system would go up to 6114 BOB equal to 883 USD and the system has a maintenance cost of 200 BOB every second year. This would make it economically feasible for the farmers to buy a system, but it would require investors or funding. With a payment plan the farmers would be able to pay off the investment without any problem.
Detta kandidatexamensarbete utgörs av en fältstudie i samhället Machacamarca utanför La Paz, Bolivia. De globala klimatförändringarna har påverkat vädret i området med högre temperaturer, oregelbunden nederbörd och oväntad frost. Detta har komplicerat det traditionella jordbruket och påverkat skörden. En av de viktigaste inkomstkällorna i samhället är det lokala mejeriet som producerar mejerivaror av mjölken från de lokala bönderna. Huvudsyftet med denna rapport är att undersöka den ekonomiska förbättringen samhället skulle få vid en implementering av ett bevattningssystem drivet av solenergi och ifall det skulle vara genomförbart. Simuleringsprogrammet, Decision support system for agrotechnology transfer, DSSAT, har använts för att simulera jordbruket och skörden för de två grödorna alfalfa och korn som i första hand används till foder. Nödvändiga data har hämtats ifrån Machacamarca och används för att simulera skörden för de tre scenariona, business as usual, ideal bevattning och begränsad bevattning bestämd från de lokala förhållandena. En Matlab kod baserad på nummer och parametrar funna under fältstudien används för att skapa ekonomiska simulationer för de olika skördarna för att få ekonomiska resultat från flera steg i processen. De slutgiltiga ekonomiska resultaten jämförs mot varandra samt mot kostnaderna för det valda pump- och bevattningssystemet. De båda bevattnade scenariona visar på en stabiliserad och förbättrad skörd, men endast det tredje scenariot är genomförbart i Machacamarca på grund av vattenbegränsningar. Detta gör det möjligt att föda upp 0.47 fler kor per hektar vilket förbättrar böndernas och mejeriets inkomst med 94,57 %. Vattenanvändningen när bevattning är nödvändigt är 1.33 liter per kvadratmeter vilket gör att Shurflo 8000 är det lämpligaste alternativet drivet av en 130 W solpanel och ett batteri. Investeringskostnaden för systemet skulle uppgå till 6114 BOB med en underhållskostnad på 200 BOB vartannat år. Detta skulle innebära att det är ekonomiskt möjligt för bönderna att köpa ett sådant system, men det skulle krävas investerare eller någon typ av finansiering. Med en avbetalningsplan så skulle bönderna kunna betala av hela kostnaden utan problem.

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Dye, Daniel J. "Spatial Light Dilution as a Technique for Conversion of Solar Energy to Algal Biomass." DigitalCommons@USU, 2010. https://digitalcommons.usu.edu/etd/751.

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A photobioreactor has been designed and developed to efficiently utilize solar irradiance through spatial dilution of sunlight. The concept of spatial light dilution is simple: incident sunlight is spread over a large surface area, thus reducing the photon flux density of the light. The implementation of this technique, however, is difficult. The reactor described within uses a new approach to spatial light dilution, utilizing recently-developed optical components to diffuse concentrated sunlight inside an algae culture. Preliminary productivity tests indicate a 2-3 fold increase in productivity per unit aperture (sunlight collection area) over a control reactor with direct-sunlight. Aperture productivity of up to 15 gm m-2 day-1 and total solar efficiency of 2% were achieved. A new parameter and yield coefficient are introduced. The parameter total light delivered is defined as the quantity of photons delivered per unit volume per day. The coefficient for yield of biomass on photons is also introduced. For the organism studied in this research, Neochloris oleoabundans, the yield of biomass on photons is approximately 1.09 gm mass per mol photons. The total light delivered to a culture over 24 hours, multiplied by the yield coefficient, provides an estimate of the volumetric productivity of the reactor in sequential-batch operation. In a series of laboratory studies, the total light delivered ranged from 0.097 to 0.945 mol photons L-1 day-1, and the volumetric productivity ranged from 0.11 to 0.945 gm L-1 day-1. A reactor productivity model, integrating reactor geometry and optics with the biomass yield coefficient and volumetric productivity model, predicts that the model organism in the proposed reactor can produce an annual average of 40 gm biomass per square meter of collector area. The model predicts an annual aperture yield of 14.6 kg m-2, at 3% efficiency. This predictive model can be applied to any location that solar data exists, and the techniques can be applied to other types of organisms and reactors to provide productivity estimates.

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Basso, Diego Morello. "Simulação do sistema de aquecimento de ar de um secador solar híbrido de produtos agroalimentícios usando o TRNSYS." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2017. http://hdl.handle.net/10183/163743.

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O presente trabalho tem por objetivo principal apresentar a avaliação térmica, energética e financeira para um sistema de aquecimento de ar de um secador solar híbrido de produtos agroalimentícios, o qual utiliza como fonte de energia a energia solar e uma fonte de energia auxiliar. Dois tipos de fonte de energia auxiliar são utilizados, uma fonte utiliza biomassa como combustível e a outra utiliza energia elétrica. O sistema é composto por um coletor solar térmico, tipo placa plana de exposição indireta, uma fonte de energia auxiliar. O software TRNSYS é utilizado como ferramenta para executar as simulações, tendo como meta alcançar a temperatura do ar de 70°C na entrada da câmara de secagem. Os resultados são apresentados em função das temperaturas da placa absorvedora, do ar de saída do coletor solar e do ar de entrada na câmara de secagem e em função da quantidade de energia, por hora, fornecida para o ar de secagem pelo coletor solar (ganho de energia útil) e pela fonte de energia auxiliar. Calcula-se o custo horário da energia considerando a utilização da biomassa e da energia elétrica, resultando no custo da biomassa equivalente a 42,5% do custo da energia elétrica.Embora os custos com insumos sejam mais baratos para a utilização do sistema com biomassa, a implementação desse sistema é mais cara, sendo viável apenas em longo prazo. O retorno do investimento para o sistema com biomassa ocorre no quarto ano, enquanto que o sistema com energia elétrica obtém retorno no primeiro ano.
This work aim to perform thermal, energy and financial analysis for an air heating system of a hybrid solar dryer for agricultural products, which uses as energy source a combination of solar energy and an auxiliary power source. Two types of external auxiliary power source for energy are used, biomass and electric power. The dryer is composed by an indirect flat plate flat plate collector, an external energy source and a drying chamber. The software TRNSYS is used to run the hybrid solar dryer simulations. The simulations goal is for the system to achieve 70°C air temperature at the drying chamber inlet. The results are showed as a function of the absorber flat plate temperature, the solar thermal collector outlet air temperature and the drying chamber inlet air temperature as a function of the energy amount per hour supplied to the drying air by the solar collector (useful energy gain) and by the external auxiliary power source. The energy cost per hour is calculated by assuming each one of the sources, biomass and electric power. It resulted that biomass costs 42.5% of the electrical power total costs. Although the source material costs are cheaper for biomass usage, it implies higher implementation costs, thus requiring long range usage analysis to prove practicable. The biomass system return of investment occurs at the fourth year while at the electrical power system return of investment occurs at the first year.

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Queluz, João Gabriel Thomaz 1985. "Estudo da eficiência da desinfecção solar de águas residuárias domésticas em reatores de diferentes colorações /." Botucatu, 2013. http://hdl.handle.net/11449/93826.

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Orientador: Rodrigo Máximo Sánchez Román
Banca: Raimundo Leite Cruz
Banca: Marcos Vinicius Folegatti
Resumo: A utilização de água residuária doméstica (ARD) na agricultura irrigada exige medidas de desinfecção para garantir padrões de qualidade e proteger a saúde humana dos patógenos presentes. Raios UV são eficientes para esta finalidade e há diversos relatos de sistemas de desinfecção solar (SODIS - solar disinfection), tanto para a desinfecção de água para consumo humano quanto para a desinfecção de ARD. Não há estudos sobre a eficiência da desinfecção de ARDs utilizando-se diferentes revestimentos nos reatores solares de concreto. O objetivo do presente trabalho foi avaliar a eficiência da desinfecção solar de ARD para reúso na agricultura em reatores solares com diferentes colorações: preta, branca e concreto. A ARD, após passar pelo tanque séptico, era conduzida aos reatores, formando lâminas de água residuária com 10 cm de profundidade, que ficavam expostas à radiação solar durante três dias consecutivos. A eficiência da desinfecção foi avaliada pela concentração de coliformes fecais (CF), demanda química de oxigênio (DQO), temperatura do efluente, radiação global, radiação UV, pH e sólidos suspensos totais (SST). Os dados foram analisados utilizando-se análise de regressão propondo-se um modelo matemático que representa a inativação de patógenos. O efluente do tanque séptico utilizado na desinfecção solar apresentou em média os seguintes padrões de qualidade: 1,29 x 106 NMP 100mL-1 (Número mais provável a cada 100ml), 654,96 mgDQO L-1, 180,33 mgSST L-1 e 6,17 de pH. Durante o processo constataram-se melhorias nos padrões DQO e SST nos reatores.
Abstract: The use of domestic wastewater (DWW) in irrigated agriculture requires disinfection measures to protect human health from pathogens. UV rays are effective for this purpose and there are many reports of solar disinfection (SODIS) systems, for both disinfection of drinking water and disinfection of DWW. The literature does not present any studies on the disinfection efficiency of DWW using different colors in concrete solar reactors. The aim of this study was to evaluate the efficiency of DWW solar disinfection for agriculture reuse in solar reactors with different colors: black, white and concrete. DWW, after passing through the septic tank was conducted to the reactors until the water depth reach 10 cm that was exposed to sunlight for three consecutive days. The disinfection efficiency was evaluated by the concentration of fecal coliforms (FC), chemical oxygen demand (COD), effluent temperature, global radiation, UV radiation, pH and total suspended solids (TSS). The data were analyzed using regression analysis and a mathematical model that represents the inactivation of pathogens was proposed. The effluent from the septic tank used for solar disinfection had the following mean quality standards: 1.29 x 106 MPN 100mL-1 654.96 mgCOD L-1, 180.33 mgSST L-1 and pH 6.17. During the process it was noticed improvement in COD as well as TSS concentration in the reactors. Furthermore, the results show that the effluent in different reactors had distinct temperatures: the highest rates were observed in the black reactor ...
Mestre

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Queluz, João Gabriel Thomaz [UNESP]. "Estudo da eficiência da desinfecção solar de águas residuárias domésticas em reatores de diferentes colorações." Universidade Estadual Paulista (UNESP), 2013. http://hdl.handle.net/11449/93826.

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A utilização de água residuária doméstica (ARD) na agricultura irrigada exige medidas de desinfecção para garantir padrões de qualidade e proteger a saúde humana dos patógenos presentes. Raios UV são eficientes para esta finalidade e há diversos relatos de sistemas de desinfecção solar (SODIS – solar disinfection), tanto para a desinfecção de água para consumo humano quanto para a desinfecção de ARD. Não há estudos sobre a eficiência da desinfecção de ARDs utilizando-se diferentes revestimentos nos reatores solares de concreto. O objetivo do presente trabalho foi avaliar a eficiência da desinfecção solar de ARD para reúso na agricultura em reatores solares com diferentes colorações: preta, branca e concreto. A ARD, após passar pelo tanque séptico, era conduzida aos reatores, formando lâminas de água residuária com 10 cm de profundidade, que ficavam expostas à radiação solar durante três dias consecutivos. A eficiência da desinfecção foi avaliada pela concentração de coliformes fecais (CF), demanda química de oxigênio (DQO), temperatura do efluente, radiação global, radiação UV, pH e sólidos suspensos totais (SST). Os dados foram analisados utilizando-se análise de regressão propondo-se um modelo matemático que representa a inativação de patógenos. O efluente do tanque séptico utilizado na desinfecção solar apresentou em média os seguintes padrões de qualidade: 1,29 x 106 NMP 100mL-1 (Número mais provável a cada 100ml), 654,96 mgDQO L-1, 180,33 mgSST L-1 e 6,17 de pH. Durante o processo constataram-se melhorias nos padrões DQO e SST nos reatores.
The use of domestic wastewater (DWW) in irrigated agriculture requires disinfection measures to protect human health from pathogens. UV rays are effective for this purpose and there are many reports of solar disinfection (SODIS) systems, for both disinfection of drinking water and disinfection of DWW. The literature does not present any studies on the disinfection efficiency of DWW using different colors in concrete solar reactors. The aim of this study was to evaluate the efficiency of DWW solar disinfection for agriculture reuse in solar reactors with different colors: black, white and concrete. DWW, after passing through the septic tank was conducted to the reactors until the water depth reach 10 cm that was exposed to sunlight for three consecutive days. The disinfection efficiency was evaluated by the concentration of fecal coliforms (FC), chemical oxygen demand (COD), effluent temperature, global radiation, UV radiation, pH and total suspended solids (TSS). The data were analyzed using regression analysis and a mathematical model that represents the inactivation of pathogens was proposed. The effluent from the septic tank used for solar disinfection had the following mean quality standards: 1.29 x 106 MPN 100mL-1 654.96 mgCOD L-1, 180.33 mgSST L-1 and pH 6.17. During the process it was noticed improvement in COD as well as TSS concentration in the reactors. Furthermore, the results show that the effluent in different reactors had distinct temperatures: the highest rates were observed in the black reactor ...

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Raza, Khalil. "Experimental Assessment of Photovoltaic Irrigation System." Wright State University / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=wright1411072971.

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FORTUNA, Gabriel C?ssia. "Custos monet?rios do quiabeiro org?nico em fun??o de l?minas de irriga??o automatizada, ?pocas de cultivo e bombeamento solar fotovoltaico." Universidade Federal Rural do Rio de Janeiro, 2017. https://tede.ufrrj.br/jspui/handle/jspui/2226.

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The work was carried out in the Integrated Agroecological Production System (SIPA), known as Fazendinha Agroecol?gica Km 47, in the city of Serop?dica - RJ, Brazil. The objective was to evaluate the productivity, development and economic viability of the okra (Abelmoschus esculentus) of summer, in regrowth driving and in winter cultivation, when submitted to automated irrigation slides and solar photovoltaic energy. An area of 225 m2 was used and the experimental design of randomized blocks with 4 irrigation slides was used, referring to different flows of drippers (2.0, 4.0, 6.0 and 8.0 Lh-1), Arranged in 5 blocks with 4 replicates, totalizing 20 experimental plots. Irrigation management was performed by the Simplified Irrigation Trigger (ASI). Two cultivation cycles were carried out and characterized as a summer crop (October 2015 to April 2016) and later regrowth (April to August 2016) and winter crop (June to September 2016). The total and commercial yields were evaluated in the three periods, as well as quality indices and crop development. The monetary costs were realized considering the costs of implantation and conduction of the crop and the selling prices practiced in the organic and conventional retail market (free markets) and in the wholesale market, being determined the net income, the rate of return and the index of profitability. The monetary costs of the photovoltaic system were calculated from the irradiance data during the cultivation period and the energy consumption of the pump. There was no significant difference between the treatments tested for all variables, except for total and commercial productivity in the eleventh week of winter cultivation. The analysis of monetary costs confirmed the production results, indicating that the lowest applied blade is responsible for the greater profitability and efficiency of water use, even commercializing the production by the values practiced in the conventional wholesale market. Likewise, there was a profitability also with the increment of the photovoltaic system in the total costs of the production system, being smaller, however, when compared to the use of the electric energy for the pumping of water. The minimum yields to be achieved in order to avoid losses were within the range of productivity expected for the crop, for the summer, winter and year of production in the three commercialization systems, even with the cost increase due to the use of solar energy.
O trabalho foi realizado no Sistema Integrado de Produ??o Agroecol?gica (SIPA), conhecido como Fazendinha Agroecol?gica Km 47, no munic?pio de Serop?dica ? RJ, e teve como objetivo avaliara produtividade, o desenvolvimento e a viabilidade econ?mica do quiabeiro (Abelmoschus esculentus) no cultivo de ver?o, na condu??o de rebrota e no cultivo de inverno, quando submetido a l?minas de irriga??o automatizada e energia solar fotovoltaica. Foi utilizada uma ?rea de 225 m2 e adotado o delineamento experimental de blocos ao acaso, com 4 l?minas de irriga??o, referentes a diferentes vaz?es de gotejadores (2,0; 4,0; 6,0 e 8,0 L.h-1), dispostas em 5 blocos com 4 repeti??es, totalizando 20 parcelas experimentais. O manejo da irriga??o foi realizado pelo Acionador Simplificado para Irriga??o (ASI). Dois ciclos de cultivo foram realizados e caracterizados como cultivo de ver?o (outubro de 2015 a abril de 2016) e posteriormente sua rebrota (abril a agosto de 2016) e pelo cultivo de inverno (de junho a setembro de 2016). Foram avaliadas nos tr?s per?odos, as produtividades total e comercial, al?m de ?ndices de qualidade e desenvolvimento da cultura. Os custos monet?rios foram realizados considerando os custos de implanta??o e condu??o da lavoura e os pre?os de venda praticados no mercado varejista org?nico e convencional (feiras livres) e no mercado atacadista, sendo determinados a renda l?quida, a taxa de retorno e o ?ndice de lucratividade. Os custos monet?rios do sistema fotovoltaico foram realizados a partir dos dados de irradi?ncia durante o per?odo de cultivo e do consumo energ?tico da bomba. N?o houve diferen?a significativa entre os tratamentos testados, para todas as vari?veis, exceto para a produtividade total e comercial na d?cima primeira semana do cultivo de inverno. A an?lise dos custos monet?rios confirmou os resultados de produ??o, indicando que a menor l?mina aplicada ? respons?vel pela maior lucratividade e efici?ncia do uso da ?gua, mesmo comercializando a produ??o pelos valores praticados no mercado atacadista convencional. Da mesma forma, houve rentabilidade tamb?m com o incremento do sistema fotovoltaico nos custos totais do sistema de produ??o, sendo menor, por?m, quando comparada ao uso da energia el?trica para o bombeamento de ?gua. As produtividades m?nimas a serem alcan?adas para que n?o ocorram preju?zos ficaram dentro da faixa de produtividade esperada para a cultura, para o cultivo de ver?o, inverno e ano de produ??o, nos tr?s sistemas de comercializa??o, mesmo com o incremento de custo devido ao emprego da energia solar.

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Silveira, Luciano Roberto da. "Sistema de aquisição de dados utilizando telemetria: aplicação em secador solar de produtos agrícolas." Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/11/11131/tde-07022012-145453/.

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A secagem para conservação de produtos agrícolas e alimentícios e feita geralmente com emprego de eletricidade ou combustível fóssil, que incrementa o custo do produto final. Dessa forma, faz-se necessário o desenvolvimento de sistemas que utilizam energia renovável, como a solar, de modo a reduzir custos sem prejuízo na qualidade do produto. Assim, um secador solar de convecção natural misto foi projetado e construído, bem como um sistema de aquisição de dados (SAD) utilizando telemetria, para monitorar temperatura e umidade relativa, ambas do ar, no interior do secador. Para o projeto do secador pesquisou-se na literatura diversos modelos já estudados, a m de reunir idéias para definição de um modelo particular. Apos construiu, um teste operacional foi realizado no secador, utilizando tomate cereja. O SAD foi construído em três partes: o transmissor com os sensores, protegido em caixa selada e afixado ao secador solar; o receptor, acoplado a um PC em local abrigado e cerda de 60 m distante do secador; e o software de aquisição de dados no PC. Os sensores foram fixados em três pontos diferentes do secador e protegidos com pedaços de tubo de PVC. O transmissor permite visualização instantânea de dados num LCD, gravação em cartão de memória SD e transmissão via RF para o receptor/PC. O software no PC e um aplicativo web, permitindo acesso externo e apresentando os dados em forma de gracos, tabela ou ilustração, alem de possuir um sistema de alerta via SMS para temperatura. Em testes de campo, o SAD apresentou bom funcionamento. Houve pouca perda de dados na transmissão, devido a veículos no caminho do sinal RF, e os sensores responderam corretamente as variações do ambiente. O secador apresentou boa resistência as intempéries, e o teste com tomate cereja mostrou que esta operacional.
Drying for preservation of agricultural and food products is usually done with the use of electricity or fossil fuel, increasing the cost of the nal product. Therefore, it is necessary to develop systems that use renewable energy such as solar, to reduce costs without impairing the quality of the product. Thus, a mixed-mode natural-circulation solarenergy dryer and a telemetry data acquisition system (DAS) to log air temperature and air relative humidity inside the dryer were designed and built. For the dryer design, in the literature several models already studied were investigated in order to gather ideas for dening a particular model. Once built, an operational test was conducted in the dryer, using cherry tomatoes. The DAS was built in three parts: the transmitter with the sensors, protected in a weather-resistant enclosure and xed in the solar dryer; the receiver, coupled to a PC in a sheltered place; and the PC software data acquisition. The sensors were put at three dierent points in the dryer and xed with PVC pipe pieces. The transmitter allows data instant viewing on an LCD, SD card logging and RF transmission to the receiver/PC. The PC software is a web application, allowing external access and presenting the data in graph, table or illustration, in addition to having an alert system to temperature by SMS. In eld tests, the DAS was worked well. There was little data loss in transmission due to vehicles in the RF signal path, and sensors correctly responded to the changing environment. The dryer had good weather resistance, and the test with cherry tomatoes showed that it is operational.

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Forson, Francis Kofi. "Modelling and experimental investigation of a mixed-mode natural convection solar crop dryer (MNCSD)." Thesis, De Montfort University, 1999. http://hdl.handle.net/2086/4201.

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Joubert-Garnaud, Carole. "Les énergies renouvelables dans l’agriculture de la Charente-Maritime : l’émergence en milieu rural d’un nouveau moteur du développement économique et social non dépourvu d’incidences sur l’environnement local." Thesis, La Rochelle, 2010. http://www.theses.fr/2010LAROF035/document.

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Cette thèse porte sur la place nouvellement attribuée aux énergies renouvelables dans un département français encore largement rural, la Charente-Maritime, alors que commence à se poser, ici comme ailleurs, la question du changement climatique et celle de l’épuisement des énergies fossiles dans un contexte privilégiant de plus en plus la mise en place de mesures de protection de l’environnement. La thèse passe en revue les différentes énergies renouvelables d’ores et déjà produites et utilisées en Charente-Maritime ou dont la mise en œuvre est envisagée (hydroélectricité, solaire, éolien, énergie issue de la biomasse). Plusieurs exemples précis d’exploitations agricoles impliquées dans la production et la consommation de ces nouvelles énergies sont longuement présentés. La thèse s’intéresse également au potentiel de développement de ces énergies, à leurs retombées sur l’environnement et à la façon dont elles sont perçues, tant par les agriculteurs que les élus locaux, les responsables d’associations ou les habitants en général. Il apparaît clairement que la politique de développement des énergies renouvelables actuellement menée en Charente-Maritime est incitative, tout particulièrement en ce qui concerne l’énergie solaire et la biomasse énergie au profit desquelles les aides régionales et départementales sont importantes (mise en œuvre d’une filière locale bois – énergie dans le pays Saintonge Romane). Par contre, l’édification de parcs éoliens est freinée par les pouvoirs publics en raison de leur trop fort impact paysager dans un département à vocation touristique affirmée. La thèse montre, en fin de compte, que le bilan environnemental que l’on peut tirer de toutes ces innovations apparaît mitigé : le recours aux énergies renouvelables réduit un peu la dépendance des campagnes charentaises à l’égard des énergies fossiles, mais l’impact environnemental direct de ces nouvelles sources d’énergie apparaît ambigu et pour le moins contrasté. L’étude, quoique conduite dans un cadre territorial relativement restreint, est néanmoins largement représentative des transformations en cours dans les campagnes françaises, voire européennes, les particularités locales et nationales ayant été clairement soulignées
This thesis deals with the newly role given to the renewable energies in a still rural French area, The Charente Maritime, while here and there, two issues are at stake : the question of climate change as well as the dramatic decrease of fossil energy stocks, in a period more and more turning towards the implementation of environment protection measures.Our research makes a review of the different renewable energies. Firstly the ones already produced and used in Charente Maritime, secondly the ones whose implementation is planned and eventually those which are in a state of project. (hydroelectric, solar, wind and biomass energies). The thesis is also about the potential of these energies expansion, about their consequences on environment, and in the way farmers, local representatives, association leaders and inhabitants view them.As a conclusion the thesis shows that environment results that we can draw from all these innovations is mixed : while the use of renewable energies reduce a little the dependence of Charentaises countries from fossil energies, the direct environment impact of these new energy sources appears ambiguous and especially contrasted. The study has been made in a quite little geographical area. It is all the same representative of the current changes in the French as well as the European countryside, the local and national specificities having been clearly underlined

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Bafana, Ramzi, and Zain Zulfiqar. "Solar Energy." Thesis, Blekinge Tekniska Högskola, Institutionen för tillämpad signalbehandling, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-2079.

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This thesis is about Photovoltaic (PV) cells and its stresses in various directions by calculating the power generated using solar cells under different conditions to improve its efficiency. Our research studies found that using multi-junction cells with larger substrates can increase the efficiency to some extent which in practice is limited to 43 percent. The experiment was conducted using ten solar cells each with an area of 20.9〖cm〗 ^2, where each cell gives 0.5 V and 0.4 A and a 1.25 Ω resistor was used. The cells were connected in series. Once, the PV cells were fixed horizontally and the other time tested in tilted position under same outdoor condition. The purpose of testing PV cells was to investigate the efficiency under above mentioned conditions. The data collected from the readings was used in calculation, and we have obtained from the calculations that horizontally fixed cells gave 4.8 percent efficiency whereas tilted cells gave 6.6 percent efficiency. Hence, the ratio showed that fixed cells produced 37.5 percent more power compared to horizontally fixed cells. Our other experiment consisted of testing PV cells under different temperature conditions that was done using a freezer and an oven for temperature variation and a tungsten bulb was used as a light source. The purpose of performing this experiment was to investigate how the efficiency of PV cells is affected under extreme conditions. Part of our thesis was also including studies and analysis of produced energy by the solar panel installed on the roof of “BTH” building in Karlskrona, Sweden. The data consisted of energy produced from February up to August 2014. The investigation also included finding the highest produced energy during these months. We have found that the highest energy was generated on the 1st of July which was 12.86 kWh. Furthermore, we went deep into investigation of the 1st of July to know exactly which hour of that day the highest energy was produced. The data showed that the highest produced energy was at 12:19 and 13:19 which was 2.03 kWh.
Ramzi: +46723231353, +966561993488 Zain:

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Osta, Diana. "KAN SOLEN KYLA LÖKAR? : En studie av soldrivet kylsystem i Nashik, Indien." Thesis, Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-41765.

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Sammanfattning Mer än en fjärdedel av Indiens befolkning motsvarande 311 miljoner människor saknar elanslutning. Det allra flesta av dem bor i fattigar landsbygden. Indien är även en av dem största producenterna av lök i världen där staten Maharashtra står för 30 % och distriktet Nashik för 60 %. Gällande förvaringen av lök på landsbygden i Nashik, i området Sinnar, är det ett problem. Under perioder med hög temperatur och hög luftfuktighet i distriktet ruttnar lökarna som förvaras som resultat kan inte bönderna sälja sina lökar på marknaden och allt slängs. Med hjälp av den icke-statliga organisationen Yuva Mitra i Indien och Mälardalens Högskola har detta arbete kunnat utföras till följd att hjälpa bönderna. Syftet med detta arbete har varit att komma med ett förbättringsförslag av nuvarande förvaringslager till lökarna. Främst att bönderna ska kunna bevara sina lökar i gott skick och öka deras livslängd så att dem kan användas och säljas till marknaden framöver. Fältstudier gjordes i Sinnar under två månader där det ingick intervjuer med bönder, producentföretag, chefer på ” National bank for agriculture and rural development” (NABARD) och kyl företag i både Sverige och Indien. Observationer gjordes också på tre olika förvaringslagrar och andra jordbruksfält i både byn Vadangali och Wadgaon. Beräkningar på en kyleffekt gjordes i Sverige med hjälp av en beräkningsmall, för kylbehovsberäkning av kyllager, och med hjälp av litteraturstudier. Programmet PVsyst användes för att beräkna hur stort ett solcellssystem krävs för att driva en kompressorkylmaskin. Revit användes för ritning av en exempel modell på ett kyllager med bestämt material och mått. Ekonomisk utvärdering utfördes för att se investeringskostnaden och återbetalningstiden. Ett förvaringslager i byn Vadangali valdes för detta arbete som utpunkt för förbättring. Lagret har en area på 105 m2, volym på 420 m3 och rymmer maximalt 50 ton lök. Förvaringstiden är på 8 månader mellan mars och oktober månad. Materialet som används idag är av lokalnivå, trä längder, plåt och stålgaller, lagret är sponsrat av regeringen och kostade cirka 35 500 kr. Arbetet inkluderade utformandet av ett kyllager med en kompressorkylmaskin driven av ett fristående solcellssystem. Det föreslagna kyllagret har samma area som det nuvarande, dock en annan volym på 525 m3, och är dessutom utformat för att klara av en inomhustemperatur på 0°C. Detta kräver en kyleffekt av 20 kW samt en soleffekt av 18,48 kW med arean 153 m2 på solpanelen som skall placeras på marken med hjälp av en ställning. Solpanelens ska även placeras med en riktning mod syd och ha en vinkel på 20 grader för att uppnå maximal effekt. Två resultat åstadkoms av detta arbete varav ena är ett självbyggt kyllager med ett solcellssystem, och den andra en prefabricerad kyllager med ett kylaggregat med samma solcellssystem. Som slutsats av detta arbete är bästa lösningen med lägst investeringskostnad och återbetalningstid en prefabricerad kyllager med kylaggregat och ett solcellssystem som ska driva kompressorn med elenergi. Den totala investeringskostnaden med bidrag och lån från NABARD för ett sådant system kommer att kosta 240 633 kr vilket motsvarar en återbetalningstid på 4 år. Nyckelord: Kyllager, solcellssystem, solenergi, kompressorkylmaskin, Yuva Mitra, lök, producentföretag, landsbygdsutveckling, jordbruk, förvaringslager
Abstract India is one of the largest producers of onion in the world, which means that there is a great demand of storage facilities for the harvested onions. Indian onion farmers usually don’t use cold storage for their onions because of lack of electricity in the rural areas. During periods of high temperature and high humidity large quantities of stored onions rot. This results in much of the produce being wasted as the rotten onions cannot be sold to the market. This is a serious problem to the farmers in Nashik, situated in a block called Sinnar. The non-government organization Yuva Mitra in Nashik is supporting farmers to improve their storage of onions. Malardalens University has been asked to assist the NGO with this, therefore this work has been carried out to investigate how to improve the cooling of harvested onions, in order to improve the situation for the onion farmers. The aim of the study was to investigate cost- and energy effective solutions to provide electricity to the farmers, using solar power, allowing the farmers to build a cold storage. The purpose of this work has been to present a suggestion for improvement of an existing warehouse that currently is used by the onion farmers in Nashik. The main purpose is to provide a solution to the farmers that allows them to preserve their onions in good condition and increase the onions lifetime so that more onions can be sold to the market. Field studies were made in Sinnar, including interviews with farmers, the producer companies, managers at "National Bank for Agriculture and Rural Development" (NABARD) and cooling companies in both Sweden and India. Calculations of cooling effect were made in Sweden using a calculation template, for cooling calculations of cold storage, and with the help of literature. The solar program, PVsyst, was used to calculate how big a PV system has to be to operate a compressor chiller. The Revit program was used to draw a model example of a cold storage with selected materials and dimensions. An economic evaluation was conducted to determine the investment cost and payback period. The suggested cold storage has the same area as the current storage facility of 105 m2, but a larger volume of 525 m3. The suggested storage can accommodate a maximum of 50 tons of onions. It is designed to hold an indoor temperature of 0°C, which requires a cooling capacity of 20 kW and solar power of 18,48 kW with a solar panel area of 153 m2 to be placed with a position on the ground facing south at an angel of 20 degrees. The results show that the total investment with grants and loans from NABARD for such a system will be 240 633 SEK, which corresponds to a payback period of 4 years. The best solution with the lowest investment cost and with the lowest payback period is a prefabricated warehouses, which has chillers and a solar system to drive the compressor with electrical energy. Keywords: cooling storage, PV-system, solar energy, compressor chiller, Yuva Mitra, onion, Producer Company, rural development, agriculture, warehouse

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Maples, David William. "The Solar Energy Tracker." Thesis, University of Canterbury. Electrical and Computer Engineering, 2008. http://hdl.handle.net/10092/4420.

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Reference is increasingly being made towards the need for the world to find new and renewable forms of energy, especially for electric power generation, but also for space heating and the heating of water. Solar energy is one of the cheapest forms of renewable energy available and is so far one of the most underutilised resources. One contribution makes reference to the way forward as being ‘using concentrating solar power which uses parabolic mirrors to focus the solar heat (energy) and generate steam to drive electric generators’ as is currently happening in the utility power marketplace in the USA. This thesis deals with the issues surrounding the original development of a two axis solar energy tracking system (SET) in 1997. The subsequent redesign, development and upgrade, undertaken from 2002 to 2006, with its performance and efficiency being measured in 2006 and 2007 using a specially configured measurement and recording system. A Solar Energy Tracker (SET) is designed to track the sun moving in two axes, reflecting the solar radiation received on its mirrors to a target mounted at the end of a boom, at the focal point of the mirrors. In late 2005 and early 2006, a solar thermal hot water manufacturer and installer heard about the developments and requested some form of involvement, especially if Christchurch Polytechnic Institute of Technology (CPIT) provided research input and assisted in the further development and testing of solar thermal hot water systems. This sponsor offered two projects in 2006 and again in 2007. Other solar thermal hot water suppliers also requested involvement in the research and development being performed at CPIT, which led in August 2006, December 2006, June 2007 and December 2007, to a number of other solar thermal hot water and air wall systems being installed. Progressively, the roof of C block at CPIT has become full of solar thermal hot water systems and solar air wall systems, both of the conventional type and those with newer technologies at the core of their development. This thesis outlines the stages in the redesign and development of the SET, and the various stages in its testing, development and refinement up to its present form. The thesis chapters are written based around the mechanical and electrical design, the auto-tracking and daylight controls, the PLC (programmable logic controller) controller, the mirror and substrate testing, the SCADA (Supervisory Control And Data Acquisition) system, the testing and comparison with other domestic solar thermal hot water systems and finally the testing of the SET itself. It also details the future developments and outlines possible uses for the SET in its redefined form. With clean and polished mirrors the SET has proven itself capable of achieving a temperature rise across the target of 15 °C at a flow rate of 4 l/m. On some occasions this temperature rise can be in excess of 20 °C, but testing thus far, has shown this cannot be sustained for any worthwhile period of time (15-30 minutes). This translates to an efficiency of 5-10 % when related to an energy produced per twenty four hour time period. However, if the efficiency is calculated for the actual period of generation, ‘generation efficiency,’ then this figure rises to 24 %. An overview is given of associated solar thermal hot water and solar air wall system research and development (that is ongoing at CPIT) as well as the performance and efficiency graphs for the solar thermal hot water systems on test. No manufacturer’s, industry or brand trade names are mentioned, as this research is still confidential and commercially sensitive. However, the technology involved and characterised by each solar thermal system is recorded in a generic sense. The SET was originally developed with the purpose of heating hot water and today this is still the intent. The possible applications for this hot water are many and varied from electricity generation, space heating and further into developing or new industrial processes. The performances of the other domestic solar thermal hot water systems currently under test, are compared with the figures from the SET, with the maximum efficiency, presently available, being from an evacuated tube heat pipe system at up to 65 %, whereas traditional finned flat plate technologies have efficiencies after twelve months of up to 48 %.

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Parand, Foroutan. "Solar energy utilisation and evacuated tubular solar collectors." Thesis, Brunel University, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.292989.

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Hofker, Gerrit. "Desiccant cooling with solar energy." Thesis, De Montfort University, 2001. http://hdl.handle.net/2086/4274.

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Griffitts, Fletcher G. "Fullerenes in Solar Energy Cells." Digital Commons @ East Tennessee State University, 2017. https://dc.etsu.edu/honors/394.

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This project involves controlling and characterizing the morphology of the active layer in a special type of organic photovoltaics (OPVs), consisting of porphyrin-fullerene composites, with emphasis on electron exchange interactions between the two components. The Vienna Ab Initio Simulation Package (VASP) is applied to model a variety of donor-acceptor complexes containing fullerene and porphyrin in terms of their stabilities as well as their geometric, electronic, and charge transfer features. The goal is to identify supramolecular chain structures with highest occupied molecular orbitals (HOMOs) and lowest unoccupied molecular orbitals (LUMOs) that may serve as electron (hole) transfer channels in a photovoltaic device. A stable structure, involving the planar adsorption of a porphyrin unit on a C60 hexagon, has been identified. The results for fullerene have been extended to phthalocyanine–fullerene dyads where the fullerene-derived unit Phenyl-C61-butyric acid methyl ester (PCBM) is connected to a porphyrin analogous electron donor through two oxygen-linked benzene rings. In both cases, the HOMO is located on the porphyrin segment, the LUMO on the fullerene component. As a fullerene, PCBM is a material of very high electron affinity, but it has better solubility properties than fullerene. It is often used in plastic solar cells or flexible electronics in conjunction with electron donor materials such as P3HT or other polymers. The results of our work contribute to the ongoing effort of using computational modeling to identify fullerene-based materials of potential relevance for organic photovoltaics.

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Van, Zyl GHC. "Solar energy for domestic use." Thesis, Cape Technikon, 2000. http://hdl.handle.net/20.500.11838/884.

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Thesis (MTech(Chemical engineering))--Cape Technikon, Cape Town, 2000
The demand for pool heating has increased dramatically over the last few years. This is ascribed to the idea that a swimming pool is expensive and can only be used for four months of the year. Therefore, a need for a relatively inexpensive solar heating system, capable of heating pool water to comfortable temperatures for an extended period, does exist. The least expensive solar heating system for swimming pool heating on the market in South Africa is in the order of R 11000. This is a fixed system, usually mounted on the roof of a house. In order to ensure the safety of minors, a safety net or sail must be installed. This is an additional cost, which approximates R1500, yielding a total cost for safety and heating in the order of R 12500. Copper pipes packed in black material are utilised in these conventional heating systems, and it is the cost of this good heat conductor that makes these units expensive. In this study an alternative pool heating system constructed of PVC was investigated. The system is designed to be flexible, mobile, act as a safety mechanism and absorbs the maximum amount of solar energy available. Dark blue material as opposed to black PVC was selected for aesthetic reasons at the expense of maximum efficiency. The material strength was tested as well as the strength of adhesion. The influence of factors such as exposure to the sun and the effect of water containing chlorine and acid on the material were evaluated. Also, various means of channelling the water through the system for increased efficiency was investigated. A pilot model was constructed and its performance evaluated. It has been concluded that the alternative approach provides effective heating at a lower cost than current systems. Also, the durability of the design was found to be acceptable.

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Sabaawi, Ahmed Mohammed Ahmed. "Nanoantennas for solar energy harvesting." Thesis, University of Newcastle upon Tyne, 2015. http://hdl.handle.net/10443/2921.

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Recent years have witnessed an enormous interest in developing solar cells by utilising different materials to increase their efficiency. This interest was motivated by the rapid world demand on cheap and clean energy sources, where the main source of world’s power is the fossil fuels. The current photovoltaics technology can not meet the solar power market due to the very low efficiency provided. The philosophy of this thesis is to find an efficient alternative by designing an efficient nanoantenna for receiving the solar radiation and coupling it to an integrated rectifier for AC to DC conversion. This thesis presents the design and optimisation of different types of nanoantennas with a performance comparison to find the optimum solution for this application. The figure of merit in choosing the best design was the captured electric field in the feed gap of the nanoantenna and the area under curve, which is essential in calculating the harvested energy. In addition, this thesis investigates the use of nanoarray instead of single elements. The aims is to increase the captured electric field at the gap of the array where all the elements will contribute in increasing the field in one common gap. Feeding lines will be employed to drive the captured fields from the centre of each single element towards the common gap. Another reason behind using nanoarrays is to reduce the number of rectifiers by using one rectifier per array instead of one rectifier per single element, and hence increase the total efficiency. Futhermore, a simple analysis on dipole nanoantenna using method of moments (MoM) is presented in this thesis. The results obtained from this method is compared with those found from finite element method (FEM) simulations and an acceptable agreement is achieved. To calculate the total conversion efficiency of solar rectennas, it is important to compute the rectification efficiency of the metal/insulator/metal (MIM) diode along with the coupling efficiency between the antenna and the diode. To this end, quantum mechanics was used to calculate the characteristics of the MIM diode. The results show that bowtie nanoantennas are the best candidate for this application in either the single and array form since they have wider bandwidth and larger area under curve. Additionally, the analysis using MoM gives the designer better understanding on how the system works and exhibits lower complexity and reduced computational requirements.

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Yang, Sun. "Solar Energy Control System Design." Thesis, KTH, Skolan för informations- och kommunikationsteknik (ICT), 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-141489.

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This thesis covers design, simulation and implementation of a solar energy control system for an on grid energy storage device. The design covers several control methods such as energy balance control, operating mode switching and data exchange. A genetic algorithm was designed to optimize the control system parameters design, and the algorithm's simulation and real time operating system implementation showed comparable results. The control system was implemented to connect a power supply to the grid. The power supply simulated a solar panel and connected to an electrical grid via Energy Hub equipment, and the energy transfer characteristics of designed control system were tested. The results showed that the selected algorithm matches the target performance criteria.

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Sholin, Veronica. "Luminescent solar concentrators and all-inorganic nanoparticle solar cells for solar energy harvesting /." Diss., Digital Dissertations Database. Restricted to UC campuses, 2008. http://uclibs.org/PID/11984.

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Mahoney, Luther. "Solar hydrogen and solar electricity using mesoporous materials." Thesis, University of South Dakota, 2015. http://pqdtopen.proquest.com/#viewpdf?dispub=3723927.

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The development of cost-effective materials for effective utilization of solar energy is a major challenge for solving the energy problems that face the world. This thesis work relates to the development of mesoporous materials for solar energy applications in the areas of photocatalytic water splitting and the generation of electricity. Mesoporous materials were employed throughout the studies because of their favorable physico-chemical properties such as high surface areas and large porosities. The first project was related to the use of a cubic periodic mesoporous material, MCM-48. The studies showed that chromium loading directly affected the phase of mesoporous silica formed. Furthermore, within the cubic MCM-48 structure, the loading of polychromate species determined the concentration of solar hydrogen produced. In an effort to determine the potential of mesoporous materials, titanium dioxide was prepared using the Evaporation-Induced Self-Assembly (EISA) synthetic method. The aging period directly determined the amount of various phases of titanium dioxide. This method was extended for the preparation of cobalt doped titanium dioxide for solar simulated hydrogen evolution. In another study, metal doped systems were synthesized using the EISA procedure and rhodamine B (RhB) dye sensitized and metal doped titania mesoporous materials were evaluated for visible light hydrogen evolution. The final study employed various mesoporous titanium dioxide materials for N719 dye sensitized solar cell (DSSC) materials for photovoltaic applications. The materials were extensively characterized using powder X-ray diffraction (XRD), nitrogen physisorption, diffuse reflectance spectroscopy (DRS), UV-Vis spectroscopy, Fourier-Transform-Infrared Spectroscopy (FT-IR), Raman spectroscopy, chemisorption, photoluminescence (PL), X-ray photoelectron spectroscopy (XPS), and transmission electron microscopy (TEM). In addition, photoelectrochemical measurements were completed using current-voltage (I-V) curves, external quantum efficiency (EQE) curves, electrochemical impedance spectroscopy (EIS), and transient spectroscopy. The thesis work presented provides a better understanding of the role of mesoporous materials for solar hydrogen and solar electricity production.

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Beck, Madeleine, and Johannes Verweyen. "Utilization of Solar Energy in Liljeholmskajen." Thesis, KTH, Energiteknik, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-99036.

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For the sustainable development of society it is crucial to find a way to decrease dependency on fossil fuels. Buildings today are big energy-consumers making this sector an important one to examine and develop further. This thesis investigates the possibility of using solar energy in Liljeholmskajen, a district in Stockholm, by considering technical, economic and environment aspects of its implementation.This report analyses different technologies for solar energy, with its focus on thermal collectors, thin film panels and monocrystalline cells. The analysis covers factors such as the efficiency, longevity, and specific constraints for the system. Further the area of Liljeholmskajen is studied, with a focus on the energy requirements. The analysis is based on three different buildings, which are chosen to be representative for the district. Based on this analysis, the total energy demand that could be met by each type of solar energy can be assessed, and their respective costs of implementation calculated.Based on these results conclusions are drawn, including how solar energy could be used in the area in the most effective way. This report suggests that the best solution today would be a combination of solar thermal collectors and thin film panels, although this also depends on the size of the possible investment.Furthermore for the future, if the existing rock-caverns in the area were converted into heat storage facilities, the heat storage wouldn’t be a limiting factor for thermal collectors anymore, and an increased usage of thermal collectors would therefore be recommended.
För att uppnå en hållbar samhällsutveckling är det i dagsläget mycket viktigt att försöka hitta en lösning på hur man ska minska beroendet av fossila bränslen. En av de stora energiförbrukarna i dagens samhälle är alla byggnader, vilket gör denna sektor till ett viktigt föremål för vidareutveckling. Denna rapport undersöker möjligheterna för en eventuell användning av solenergi i Liljeholmskajen, en stadsdel i södra Stockholm, genom att ta i beaktning både teknik, ekonomi och miljöaspekter.Rapporten analyserar olika teknologier för användning av solenergi, med tyngdpunkten på termiska solfångare samt tunnfilms- och monokristallina solceller. Analysen omfattar områden såsom verkningsgrad, livslängd och systemspecifika begränsningar. Vidare studeras även Liljeholmskajen och dess energibehov. Analysen baseras på tre olika byggnader som kan anses vara representativa för stadsdelen. Detta leder sedan till att det totala energibehovet i Liljeholmskajen som kan täckas med hjälp av respektive teknik, samt deras investeringskostnader kan beräknas.Utifrån de erhållna resultaten har en slutsats dragits, vilken påvisar hur man på bästa sätt skulle kunna använda sig av solenergi i Liljeholmskajen. I dagsläget vore en kombination av solfångare och tunnfilms celler att rekommendera, men det är även beroende av hur stor investering man kan göra.Om man i framtiden skulle omvandla bergrummen som finns i området till värmelager så skulle inte längre lagringsmöjligheterna vara en begränsande faktor för solfångarsystem. Detta skulle innebära att en ökad användning av solfångare vore att rekommendera.

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Giddings, S. L. "Heterogeneous reactions in solar energy conversion." Thesis, Swansea University, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.637056.

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Photochemical systems for the splitting of water into hydrogen and oxygen represent an attractive route for the conversion of solar energy into a chemical fuel. However, the success of such systems depends on the identification of suitable redox catalysts for the oxidation and reduction processes. While colloidal platinum has proved to be an efficient catalyst for the reduction of water, the development of stable and effective catalysts for water oxidation has been less successful. The work described in this thesis involves the study of ruthenium dioxide hydrate (RuO₂.xH₂)O as a heterogeneous catalyst for the oxidation of water to oxygen. Although this material has already been widely used as an oxygen catalyst, there have been many doubts as to its ability to act in this capacity. In Chapter Three an attempt is made to resolve this controversy via an investigation of the stability and catalytic activity of RuO₂.xH₂O when exposed to various oxidising agents. The results indicate that the catalytic activity and corrosion stability of an RuO₂.xH₂O sample is related to its degree of hydration. In Chapter Four an investigation is described into the effect of heat-treatment of RuO₂.xH₂O at different temperatures on its physical and chemical properties. From these results it appears that any sample of RuO₂xH₂O may be transformed into a stable, reproducible oxygen catalyst by simply heat-treating it at 140-150^oC in air for ca. 5 hours. The latter conditions represent an optimum for catalytic activity where anodic corrosion is absent. This 'thermally-activated' RuO₂.xH₂O is shown to compare favourably with alternative oxygen catalysts. Chapters Five and Six involve a kinetic study of the RuO₂.xH₂O-catalysed oxidation of water by Ce(IV) ions in an attempt to elucidate the mechanism of catalysis of the oxide powder. The study is based on an electrochemical model in which the RuO₂.xH₂O particles are considered as microelectrodes. The initial charging of the RuO₂.xH₂O prior to water oxidation is discussed in Chapter Five and in Chapter Six the effect of an increase in the redox potential of the Ce⁴⁺/Ce³⁺ couple by changing the acid medium is investigated.

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Bengtsson, Tobias, and Håkan Hult. "Combining Solar Energy and UPS Systems." Thesis, KTH, Tillämpad termodynamik och kylteknik, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-148042.

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Solar Power and Uninterruptible Power Supply (UPS) are two technologies that are growing rapidly. The demand for solar energy is mainly driven by the trend towards cheaper solar cells, making it economically profitable for a larger range of applications. However, solar power has yet to reach grid parity in many geographical areas, which makes ways to reduce the cost of solar power systems important. This thesis investigates the possibility and potential economic synergies of combining solar power with UPS systems, which have been previously researched only from a purely technical point of view. This thesis instead evaluates the hypothesis that a combined solar and UPS system might save additional costs compared to regular grid-tied systems, even in a stable power grid. The primary reason is that on-line UPS systems rectifies and inverts all electricity, which means that solar energy can be delivered to the DC part of the UPS system instead of an AC grid, avoiding the installation of additional inverters in the solar power system. The study is divided into three parts. The first part is a computer simulation using MATLAB, which has an explorative method and aims to simulate a combined system before experimenting physically with it. The second part consists of experiments on a physical prototype system based on basic UPS and solar power components. The third part is an economical assessment of investment costs and energy balances, comparing two separate systems (UPS and solar power separate) to one combined (UPS & solar power). The results from the prototype system show that adding solar power to an UPS system does not interfere with the UPS functionality in any major way, however for optimal performance some additional integration may be necessary. On the contrary, the additional power terminal that the solar panels constitute, can increase system performance during certain operational conditions. The result of the economic analysis shows that a combined system has potential for both a lower investment cost due to cheaper components and increased energy savings through lower conversion losses. The conclusion from the study is that a combined solar energy and UPS system is technically feasible. Furthermore, a combined system has clear economic advantages over two separate systems. This means that a combined system might be economically profitable even in situations where a separate system is not.
Solenergi och avbrottsfri kraftförsörjning (UPS) är två tekniker som växer snabbt. Efterfrågan på solenergi ökar huvudsakligen på grund av den snabba utvecklingen mot billigare solceller, vilket lett till att solenergi blivit lönsamt i en större mängd applikationer. I många områden är solenergi dock fortfarande inte kostnadsmässigt konkurrenskraftigt jämfört med traditionella energikällor, vilket gör en fortsatt sänkning av kostnaderna för solenergi till en viktig fråga för solenergiindustrin. Detta examensarbete har som syfte att undersöka om det är tekniskt möjligt att kombinera solenergi med UPS-system samt potentialen för ekonomiska synergier med denna kombination. Tidigare forskning inom området har endast undersökt denna kombination från en rent teknisk synvinkel. Detta examensarbete driver istället hypotesen att ett kombinerat solenergi- och UPS-system kan leda till större kostnadsbesparingar jämfört med ett traditionellt nätanslutet solenergisystem, även i ett stabilt elnät som i Sverige. En on-line UPS skyddar en känslig last genom att kontinuerligt likrikta och sedan åter växelrikta inkommande ström för att därmed både isolera lasten från nätet samt höja strömkvalitén. I UPS-systemet finns därmed en likströmsdel dit solpanelerna direkt kan kopplas istället för att skicka den genererade solenergin ut på elnätet. Därmed undviks inköp och installation av sol-växelriktare i solenergisystemet. Studien är uppdelad i tre delar. Första delen är en datorsimulering i MATLAB och syftar till att explorativt undersöka det kombinerade systemet för en optimerad design innan fysiska experiment utförs. Den andra delen av studien utgörs av experiment på ett fysiskt prototypsystem baserat på ett principiellt UPS- och solenergisystem. Den tredje delen av studien är en ekonomisk analys av både investeringskostnader och energibalanser som jämför ett kombinerat system (UPS & sol) med två separata system (UPS & sol separat). Resultaten från prototypsystemet visar att påkopplandet av solceller i en principiell UPS har mycket låg påverkan på UPS-systemets funktionalitet, samt att solcellerna som en extra energikälla under vissa driftförhållanden kan ha en positiv påverkan på UPS-systemet. För optimal prestanda kan dock en viss integration av systemen krävas. Resultatet från den ekonomiska analysen visar att ett kombinerat system har potential att sänka investeringskostnaden genom billigare komponenter. Ett kombinerat system kan även leda till en högre energibesparing jämfört med ett nätanslutet solenergisystem eftersom konverteringsförlusterna i UPS-systemet sjunker i det kombinerade systemet. Slutsatsen av studierna är att ett kombinerat solenergi- och UPS-system är tekniskt möjligt. Dessutom finns betydande ekonomiska synergier med ett kombinerat system. Detta innebär att ett kombinerat system kan vara lönsamt även i fall där ett separat solelsystem inte är det.

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Bokfors, Sofie. "Awareness on Solar Energy in Kenya." Thesis, KTH, Energiteknik, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-250019.

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Solar energy coupled with energy efficiency awareness can be an important step to achieving thefinal goal of having a sustainable environment in the country. Together with a good energy policyincluding regulations, this goal can be achieved as it will help consumers make more rationaldecisions when it comes to new technology. A key problem identified in this work is the lack ofawareness and strict energy policies. The current funds put in place are not mobile and have not got to a large number of people. Thegovernment’s regulations on the other hand are not strict. This report aims to improve the currentstatus by suggesting strategies to reach out to as many people as possible and educate them aboutsolar energy options in Kenya. It aims to prepare to build a platform that creates awareness onsolar energy, energy efficiency as well as the policies and finances needed to support their uptake. In order to build this platform, analysis has been done through research and meetings withstakeholders who have provided first-hand information in order to formulate the foundation to afuture platform. The information gathered has then been used to explain and meet the challengesfaced in solar energy in Kenya. The conclusion of this project was that majority of the people inKenya lack required knowledge about solar energy. There is need to create awareness in solarenergy.

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Borg, Isak, August Dixelius, and David Östlund. "Interactive Visualization of Solar Energy Data." Thesis, Uppsala universitet, Institutionen för informationsteknologi, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-385793.

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Sweden has one of the lowest solar energy productions in Europe even though the weather conditions are comparable to Europe’s largest solar energy producer. Although the majority of the Swedish population is in favour of spending more money on services that can limit climate change, the growth of installed solar cells is slower than that of other countries with similar climate in Europe. To inspire people to install solar panels we created an interactive map with information regarding the solar parks in Uppland, a county in Sweden. Our goal was that this system would help spread awareness of the fact that solar parks work efficiently in Sweden. The program was then installed on a tablet which was put in a public space together with an LED installation to reach as broad of an audience as possible. To draw the passer by’s attention, the LED installation was connected to the map which shows the energy production of the selected solar park in a colour scale.
Sverige har en av de lägsta produktionen av solenergi i Europa trots att deras väderförhållanden är jämförbara med Europas största producenter av solenergi. Även fast majoriteten av Sveriges befolkning är villiga att spendera mer pengar på tjänster som kan begränsa klimatförändringar är tillväxten av nya solpaneler långsammare än i andra Europeiska länder med liknande klimat. För att inspirera personer att installara solpaneler har vi skapat en interaktiv karta med information gällande solparker i Uppland. Vårt mål är att programmet skulle öka medvetenheten om solparkers effektivitet i Sverige. Programmet blev sedan installerat på en surfplatta som monterades på en offentlig plats tillsammans med en LED-installation för att nå en så omfattande publik som möjligt. För att dra till sig förbipasserandes uppmärksamhet så kopplades LED-installationen till kartan som visar energiproduktionen hos den valda solparken i en färgskala.

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39

Hassan, Ibrahim. "Solar energy conversion by photoelectrochemical processes." Thesis, University of Bath, 2011. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.542078.

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40

Ferrer, Martínez Claudia. "Machine Learning for Solar Energy Prediction." Thesis, Högskolan i Gävle, Avdelningen för elektronik, matematik och naturvetenskap, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-27423.

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This thesis consists of the study of different Machine Learning models used to predict solar power data in photovoltaic plants. The process of implement a model of Machine Learning will be reviewed step by step: to collect the data, to pre-process the data in order to make it able to use as input for the model, to divide the data into training data and testing data, to train the Machine Learning algorithm with the training data, to evaluate the algorithm with the testing data, and to make the necessary changes to achieve the best results. The thesis will start with a brief introduction to solar energy in one part, and an introduction to Machine Learning in another part. The theory of different models and algorithms of supervised learning will be reviewed, such as Decision Trees, Naïve Bayer Classification, Support Vector Machines (SVM), K-Nearest Neighbor (KNN), Linear Regression, Logistic Regression, Artificial Neural Network (ANN). Then, the methods Linear Regression, SVM Regression and Artificial Neural Network will be implemented using MATLAB in order to predict solar energy from historical data of photovoltaic plants. The data used to train and test the models is extracted from the National Renewable Energy Laboratory (NREL), that provides a dataset called “Solar Power Data for Integration Studies” intended for use by Project developers and university researchers. The dataset consist of 1 year of hourly power data for approximately 6000 simulated PV plants throughout the United States. Finally, once the different models have been implemented, the results show that the technique which provide the best results is Linear Regression.

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41

Bokfors, Sofie. "Awareness on Solar Energy in Kenya." Thesis, KTH, Energiteknik, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-245193.

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Solar energy coupled with energy efficiency awareness can be an important step to achieving the final goal of having a sustainable environment in the country. Together with a good energy policy including regulations, this goal can be achieved as it will help consumers make more rational decisions when it comes to new technology. A key problem identified in this work is the lack of awareness and strict energy policies. The current funds put in place are not mobile and have not got to a large number of people. The government’s regulations on the other hand are not strict. This report aims to improve the current status by suggesting strategies to reach out to as many people as possible and educate them about solar energy options in Kenya. It aims to prepare to build a platform that creates awareness on solar energy, energy efficiency as well as the policies and finances needed to support their uptake. In order to build this platform, analysis has been done through research and meetings with stakeholders who have provided first-hand information in order to formulate the foundation to a future platform. The information gathered has then been used to explain and meet the challenges faced in solar energy in Kenya. The conclusion of this project was that majority of the people in Kenya lack required knowledge about solar energy. There is need to create awareness in solar energy.
Solenergi i kombination med medvetenhet gällande energieffektivitet är ett viktigt steg för att uppnå det slutliga målet, som är att ha en hållbar utveckling gällande energi och miljö i Kenya. Tillsammans med en bra energipolitik som har tydliga regler, kan detta mål uppnås. Detta kommer att hjälpa konsumenterna att fatta mer rationella beslut när det gäller ny teknik. Ett nyckelproblem som identifieras i detta arbete är bristen på medvetenhet och även bristen av en strikt energipolitik. Kunskapen om solenergi och energieffektivitet har inte nått ut till majoriteten av människorna i Kenya. I dagsläget är lagarna gällande energi inte tillräckligt strikta. Denna rapport syftar till att förbättra den nuvarande situationen genom att föreslå strategier för att nå ut till maximalt antal invånare och utbilda dem om solenergialternativ. Rapporten syftar till att lägga en grund för att kunna bygga upp en plattform som skapar medvetenhet om solenergi och energieffektivitet, och vad som krävs politiskt och finansiellt för att stödja detta. För att kunna bygga upp denna plattform har analyser gjorts genom litteraturstudier och möten med intressenter som har bidragit med förstahandsinformation, detta för att kunna skapa grunden till den framtida plattformen. Informationen som samlats in har sedan använts för att förklara och för att försöka möta utmaningarna gällande solenergi i Kenya. Slutsatsen av detta projekt är att majoriteten invånarna i landet saknar nödvändig kunskap om solenergi. Det är därför viktigt att skapa medvetenhet gällande solenergi.

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Liang, Xusheng, Elvis Tanyi, and Xin Zou. "Charging electric cars from solar energy." Thesis, Blekinge Tekniska Högskola, Institutionen för tillämpad signalbehandling, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-11919.

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Before vehicles were heavily relied on coal, fossil fuels and wind for power. Now, they are rapidly being replaced by electric vehicles and or plug-in hybrid electric cars. But these electric cars are still faced with the problem of energy availability because they rely on energy from biomass, hydro power and wind turbines for power generation. The abundance of solar radiation and its use as solar energy as a power source in driving these rapidly increasing electric cars is not only an important decision but also a necessary condition for eradication of environmental pollution. This study presents a model for charging electric cars from solar energy. Little focus on detailed technologies involved from solar energy capture to battery charging but our main focus is how to provide a modified charging parking lot in Karlskrona city-Sweden. With a surface area of 2850m2, we were able to choose 1STH-350-WH as the right PV modules. Based on the latitude of our design area, a computed 71 degrees angle positioning between solar panel and roof so as to maximise the surface area and optimise the solar irradiance gathering. Based on the power output of approximately116kW these PV modules generated, we further analysed and selected SDP 30KW inverter and Monocrystalline Silicon (1SolTech 1STH-350-WH (350W) solar modules. Also we provide different car charging method by choosing the SAE J1772 standard as one of specifications for dedicated vehicle charging and Clipper Creek HSC-40 as our option of charger. With the data of the generating solar energy every day, charging time, consuming power, we can estimate how many cars the system can handle to charge. Moreover, our system provides AC power from AC power network by general socket type F. We finally concluded that, our model for charging of electric car batteries was not only supportive but efficient in terms of extracting solar energy from sunlight to charge electric cars, thus making the region an eco-friendly place.

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43

Reusswig, Philip David. "Sensitized energy transfer for organic solar cells, optical solar concentrators, and solar pumped lasers." Thesis, Massachusetts Institute of Technology, 2014. http://hdl.handle.net/1721.1/93831.

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Thesis: Ph. D., Massachusetts Institute of Technology, Department of Electrical Engineering and Computer Science, 2014.
Cataloged from PDF version of thesis.
Includes bibliographical references (pages 123-130).
The separation of chromophore absorption and excitonic processes, such as singlet exciton fission and photoluminescence, offers several advantages to the design of organic solar cells and luminescent solar concentrators (LSCs) for the end goal of achieving a lower cost solar energy generation. This thesis explores three new device architectures to overcome limited solar absorption in singlet-exciton-fission based solar cells and neodymium based LSCs. The process of singlet exciton fission is de-coupled from photon absorption, exciton diffusion, and charge transport in singlet-exciton-fission based solar cells by inserting a singlet fission material at the donor-acceptor interface of an organic solar cell. Singlet excitons generated in the singlet exciton donor are transferred to the singlet fission material through near field energy transfer. In this device structure, the singlet donor can be chosen for high photon absorption, exciton diffusion, and charge transport, and the singlet fission sensitizer can be selected for high singlet fission efficiency. We demonstrated a doubling of the external quantum efficiency from 12.8% to 27.6% in a singlet donor (TPTPA) through the introduction of thin film singlet fission sensitizer (rubrene) for high efficiency organic solar cells. To reduce the cost of electricity generated by sunlight via LSC systems, replacing the expensive high efficiency visible photovoltaic (PV) elements with cheap, high efficiency, earth abundant near-infrared PV elements made with silicon. This requires replacing within the LSC the visible emitting chromophores with near infrared emitters. Here, we present the use of a lanthanide ion, neodymium--colloidal nanocrystal energy cascade system as a promising LSC emitter scheme for the silicon spectral region. Peak optical quantum efficiencies of 43% in a Nd³+:glass based LSC are demonstrated with simulated high geometric gain performance. With cascade energy transfer, the optical quantum efficiency in the visible of a Nd³+:glass is significantly improved with peak efficiency of 28%. The enhanced solar absorption of Nd³+:glass through cascade energy transfer can be extended into the infrared with more optimal sensitizers. The idea of directly converting broad-band solar radiation into coherent and narrow-band laser radiation could enable many attractive technologies for solar energy. Here, we present an architecture for solar pumped lasers that uses a luminescent solar concentrator to decouple the conventional trade-off between solar absorption efficiency and the mode volume of the optical gain material. We report a 750-[mu]m-thick Nd³+-doped YAG planar waveguide sensitized by a luminescent CdSe/CdZnS (core/shell) colloidal nanocrystal, yielding a peak cascade energy transfer of 14%, a broad spectral response in the visible portion of the solar spectrum, and an equivalent quasi-CW solar lasing threshold of 20 W-cm2 , or approximately 200 suns. The efficient coupling of incoherent, spectrally broad sunlight in small gain volumes should allow the generation of coherent laser light from intensities of less than 100 suns.
by Philip David Reusswig.
Ph. D.

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44

Mukhopadhyay, Boidurjo. "Solar energy based entrepreneurship and rural development : analysing institutional arrangements that support solar energy entrepreneurs in India." Thesis, University of Sussex, 2017. http://sro.sussex.ac.uk/id/eprint/68229/.

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Renewable energy (RE hereafter) has been observed as a potentially significant new source of jobs and rural growth in both OECD and BRICs countries, and a means of addressing environmental and energy security concerns. The global deployment of RE has been expanding rapidly. For instance, the RE electricity sector grew by 26% between 2005 and 2010 globally and currently provides about 20% of the world's total power (including hydro-power) (OECD, 2012). Rural areas attract a large part of investment related to renewable energy deployment, rending to be sparsely populated but with abundant sources of RE. Several case studies have found that RE deployment can provide hosting communities with some benefits including new revenue sources, new job and business opportunities, innovation in products/practices/policies in rural areas, capacity building and community empowerment, and affordable energy. There is a growing body of evidence on the instrumental role that entrepreneurs and small businesses play in driving local and national economies. The structure of rural economies is essentially composed of small enterprises, which are responsible for most of the job growth and the innovation. Rural development is a key element of strategies to reduce poverty and create income and employment opportunities (UNIDO, 2003). It is important to unleash and harness the creativity of grassroots entrepreneurs but they are posed with many challenges, the biggest being these grassroots inventions don't scale up. To overcome these challenges and promote rural entrepreneurship, support roles are required; this is also where the importance and role of institutions and their planned arrangements (for example, partnerships) are much debated in both domestic and international forums. This research investigates the current institutional arrangements that support solar entrepreneurship which creates solar energy based income-generating micro enterprises in rural India. In addition to that, it explores the wider implications on rural development that these entrepreneurships have while using these solar RETs. Institutions and individuals promoting rural development see entrepreneurship as a strategic development intervention that could accelerate the rural development process (Ezeibe, 2013). India, being the only country with a national ministry dedicated to RE initiatives (the MNRE, Government of India) and also ranking third on the renewable energy country attractiveness index (E&Y, 2013; 2016) makes an interesting country choice for investigation. The thesis applies a qualitative research method with an exploratory design to understand the interaction process between institutions and how different institutions support rural development to generate an in-depth analysis of existing institutions using a conceptual framework.

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Wigginton, James Michael. "Optical analysis of cavity solar energy receivers." Thesis, Georgia Institute of Technology, 1992. http://hdl.handle.net/1853/17348.

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Perumattil, Jose Rose Mary. "The analysis of flat plate solar collector with double-axis solar tracking." Thesis, Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-38932.

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47

Ray, Mike C. T. "Solar Data Analysis." PDXScholar, 2013. https://pdxscholar.library.pdx.edu/open_access_etds/1078.

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The solar industry has grown considerably in the last few years. This larger scale has introduced more problems as well as possibilities. One of those possibilities is analyzing the data coming from the sites that are now being monitored, and using the information to answer a variety of questions. We have four questions which are of prime importance identified in this thesis: 1. Can data from customers be trusted? 2. Can we use data from existing sites to determine which sites need the most improvement? 3. Can we implement a location-based algorithm to reduce the amount of false positives for performance, or other alarms? 4. Can we improve upon the current predicted power algorithm? We find that not only can we answer these questions definitively, but the improvements found are of significant value. Each of these items represents an important question that either directly or indirectly translates into increased revenue and engineering improvements for the solar industry as a whole.

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Kang, Ji-Hwan. "Energy transfer enhancement of photon upconversion systems for solar energy harvesting." Thesis, Georgia Institute of Technology, 2012. http://hdl.handle.net/1853/45846.

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Photon energy upconversion (UC), a process that can convert two or more photons with low energy to a single photon of higher energy, has the potential for overcoming the thermodynamic efficiency limits of sunlight-powered devices and processes. An attractive route to lowering the incident power density for UC lies in harnessing energy transfer through triplet-triplet annihilation (TTA). To maximize energy migration in multicomponent TTA-assisted UC systems, triplet exciton diffusivity of the chromophores within an inert medium is of paramount importance, especially in a solid-state matrix for practical device integration. In this thesis, low-threshold sensitized UC systems were fabricated and demonstrated by a photo-induced interfacial polymerization within a coaxial-flow microfluidic channel and in combination with nanostructured optical semiconductors. Dual-phase structured uniform UC capsules allow for the highly efficient bimolecular interactions required for TTA-based upconversion, as well as mechanical strength for integrity and stability. Through controlled interfacial photopolymerization, diffusive energy transfer-driven photoluminescence in a bi-molecular UC system was explored with concomitant tuning of the capsule properties. We believe that this core-shell structure has significance not only for enabling promising applications in photovoltaic devices and photochromic displays, but also for providing a useful platform for photocatalytic and photosensor units. Furthermore, for improving photon upconverted emission, a photonic crystal was integrated as an optical structure consisting of monodisperse inorganic colloidal nanoparticles and polymer resin. The constructively enhanced reflected light allows for the reuse of solar photons over a broad spectrum, resulting in an increase in the power conversion efficiency of a dye-sensitized solar cell as much as 15-20 %.

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Hobday, R. A. "Passive solar-energy air-heating wall panels." Thesis, Cranfield University, 1987. http://hdl.handle.net/1826/4157.

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The development of products which enable passive solar-energy air-heating to be integrated into the heating strategies of public, commercial and industrial buildings is described. These buildings are, in general, only occupied significantly during the day; consequently the bulk of heating demand coincides with the period of solar gain. In these circumstances collected solar heat should be delivered with the minimum of delay. The design and operation of units which are capable of supplying solar heated air in this manner is outlined. These are passive, naturalcirculation air-heating collectors, also known as natural-convection air-heaters, or thermosyphoning air panels. Four methods of retrofitting such solar collectors to non-domestic buildings have been identified, one of which, the overcladding collector, has not been proposed previously. Problems associated with the successful installation and operation of these units have also been considered. The relative merits of a number of methods of testing passive solarenergy air-heating collectors have been investigated. A method of determining instantaneous collector efficiency based on the measurement of glazing temperature, inlet and outlet air temperature, ambient temperature and insolation has been developed. Three novel design proposals have been presented: i) a collector constructed with the insulation fitted outside, rather than inside, so that the metal body of the collector may provide more symmetrical heating of the air flow than the conventional arrangement, ii) an absorber which consisted of parallel ducts to increase the rate of heat transfer to the air, heating it symmetrically, (iii) a hinged air-deflector for conversion from the heating to the ventilation mode.

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Liu, Suyao, and Li Xie. "Investigation of solar energy utilization in China." Thesis, Högskolan i Gävle, Akademin för teknik och miljö, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-14688.

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Dissertations / Theses on the topic 'Solar energy Solar energy in agriculture'

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