Academic literature on the topic 'Photovoltaics - NCs'
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Journal articles on the topic "Photovoltaics - NCs"
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Mirabella, Salvo, Salvo Cosentino, and Antonio Terrasi. "Synthesis and Light Absorption Mechanism in Si or Ge Nanoclusters for Photovoltaics Applications." Solid State Phenomena 205-206 (October 2013): 465–74. http://dx.doi.org/10.4028/www.scientific.net/ssp.205-206.465.
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Photon absorption in the solar energy range has been investigated in semiconductor nanostructures. Different synthesis techniques (magnetron sputtering, plasma enhanced chemical vapor deposition, ion implantation) followed by thermal annealing, have been employed to fabricate Si or Ge nanoclusters (1-25 nm in size) embedded in SiO2or Si3N4matrices. The thermal evolution in the formation of Si nanoclusters (NCs) in SiO2was shown to depend on the synthesis technique and to significantly affect the light absorption. Experimentally measured values of optical bandgap (EgOPT) in Si NCs evidence the quantum confinement effect which significantly increases the value ofEgOPTin comparison to bulk Si.EgOPTspans over a large range (1.6-2.6 eV) depending on the Si content, on the deposition technique and, in a most significant way, on the structural phase of NC. Amorphous Si NCs have a lowerEgOPTin comparison to crystalline ones. The matrix effect on the synthesis and light absorption in semiconductor NCs was investigated for Ge NCs. Large difference in the Ge NCs synthesis occurred when using SiO2or Si3N4matrices, essentially due to a much lower Ge diffusivity in the latter, which slows down the formation and growth of Ge NCs in comparison to silica matrix. Light absorption in NCs is also shown to be largely affected by the host matrix. Actually, Ge NCs embedded in Si3N4material absorb photons in the solar energy range with a higher efficiency than in silica, due to the different confinement effect. In fact, Si3N4host offers a lower potential barrier to photogenerated carriers in comparison to silica, thus a lower confinement effect is expected, leading to slightly smaller optical bandgap. These effects have been presented and discussed for potential application in light harvesting purposes.
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Kovalenko, Maksym V., Loredana Protesescu, and Maryna I. Bodnarchuk. "Properties and potential optoelectronic applications of lead halide perovskite nanocrystals." Science 358, no. 6364 (November 9, 2017): 745–50. http://dx.doi.org/10.1126/science.aam7093.
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Semiconducting lead halide perovskites (LHPs) have not only become prominent thin-film absorber materials in photovoltaics but have also proven to be disruptive in the field of colloidal semiconductor nanocrystals (NCs). The most important feature of LHP NCs is their so-called defect-tolerance—the apparently benign nature of structural defects, highly abundant in these compounds, with respect to optical and electronic properties. Here, we review the important differences that exist in the chemistry and physics of LHP NCs as compared with more conventional, tetrahedrally bonded, elemental, and binary semiconductor NCs (such as silicon, germanium, cadmium selenide, gallium arsenide, and indium phosphide). We survey the prospects of LHP NCs for optoelectronic applications such as in television displays, light-emitting devices, and solar cells, emphasizing the practical hurdles that remain to be overcome.
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Bastola, Ebin, Kamala Khanal Subedi, Khagendra P. Bhandari, and Randy J. Ellingson. "Solution-processed Nanocrystal Based Thin Films as Hole Transport Materials in Cadmium Telluride Photovoltaics." MRS Advances 3, no. 41 (2018): 2441–47. http://dx.doi.org/10.1557/adv.2018.349.
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ABSTRACTThe cadmium telluride (CdTe) photovoltaic (PV) comprise an efficient and cost-effective technology for harvesting solar energy. However, device efficiency remains limited in part by low-open circuit voltage (VOC) and fill factor (FF) due to inefficient transport of photo-generated charge carriers. Given the deep valence band of CdTe, the use of copper/gold (Cu/Au) as a back contact serves primarily to narrow the width of the inherent Schottky junction evident in CdTe solar cells (in our laboratory, Cu/Au has been used as a standard back contact). For efficient transport of carriers to and into the back contact, a hole transport layer (HTL) is desired with valence band edge comparable to that of CdTe (∼ -5.9 eV). Here, we report solution-processed nanocrystal (NCs) based thin films as HTLs in CdTe solar cells. The earth abundant materials we discuss include iron pyrite (FeS2), nickel-alloyed iron pyrite (NixFe1-xS2), zinc copper sulfide (ZnxCu1-xS) nanocomposites, and perovskite-based films. The FeS2 and NixFe1-xS2 NCs are synthesized by a hot-injection route, and thin films are fabricated by drop-casting, and spin-coating techniques using colloidal NCs. ZnxCu1-xS thin films are fabricated by chemical bath deposition. These NC-based thin films are applied and studied as the HTLs in CdTe devices. On using these materials, the device performance can be increased up to 10% compared to the standard Cu/Au back contact. Here, we discuss the benefits, challenges, and opportunities for these back contact materials in CdTe photovoltaics.
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Zaffalon, Matteo L., Valerio Pinchetti, Andrea Camellini, Sergey Vikulov, Chiara Capitani, Bing Bai, Meng Xu, et al. "Intrinsic and Extrinsic Exciton Recombination Pathways in AgInS2 Colloidal Nanocrystals." Energy Material Advances 2021 (April 5, 2021): 1–10. http://dx.doi.org/10.34133/2021/1959321.
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Ternary I-III-VI2 nanocrystals (NCs), such as AgInS2 and CuInS2, are garnering interest as heavy-metal-free materials for photovoltaics, luminescent solar concentrators, LEDs, and bioimaging. The origin of the emission and absorption properties in this class of NCs is still a subject of debate. Recent theoretical and experimental studies revealed that the characteristic Stokes-shifted and long-lived luminescence of stoichiometric CuInS2 NCs arises from the detailed structure of the valence band featuring two sublevels with different parity. The same valence band substructure is predicted to occur in AgInS2 NCs, yet no experimental confirmation is available to date. Here, we use complementary spectroscopic, spectro-electrochemical, and magneto-optical investigations as a function of temperature to investigate the band structure and the excitonic recombination mechanisms in stoichiometric AgInS2 NCs. Transient transmission measurements reveal the signatures of two subbands with opposite parity, and photoluminescence studies at cryogenic temperatures evidence a dark state emission due to enhanced exchange interaction, consistent with the behavior of stoichiometric CuInS2 NCs. Lowering the temperature as well as applying reducing electrochemical potentials further suppress electron trapping, which represents the main nonradiative channel for exciton decay, leading to nearly 100% emission efficiency.
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Havryliuk, Yevhenii, Volodymyr Dzhagan, Anatolii Karnaukhov, Oleksandr Selyshchev, Julia Hann, and Dietrich R. T. Zahn. "Raman Spectroscopy and Thermoelectric Characterization of Composite Thin Films of Cu2ZnSnS4 Nanocrystals Embedded in a Conductive Polymer PEDOT:PSS." Nanomaterials 13, no. 1 (December 22, 2022): 41. http://dx.doi.org/10.3390/nano13010041.
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Cu2ZnSnS4 (CZTS) is an intensively studied potential solar cell absorber and a promising thermoelectric (TE) material. In the form of colloidal nanocrystals (NCs), it is very convenient to form thin films on various substrates. Here, we investigate composites of CZTS NCs with PEDOT:PSS, a widely used photovoltaics polymer. We focus on the investigation of the structural stability of both NCs and polymers in composite thin films with different NC-to-polymer ratios. We studied both pristine films and those subjected to flash lamp annealing (FLA) or laser irradiation with various power densities. Raman spectroscopy was used as the main characterization technique because the vibrational modes of CZTS NCs and the polymer can be acquired in one spectrum and thus allow the properties of both parts of the composite to be monitored simultaneously. We found that CZTS NCs and PEDOT:PSS mutually influence each other in the composite. The thermoelectric properties of PEDOT:PSS/CZTS composite films were found to be higher compared to the films consisting of bare materials, and they can be further improved by adding DMSO. However, the presence of NCs in the polymer deteriorates its structural stability when subjected to FLA or laser treatment.
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Xu, Ao, Qichuan Huang, Kaiying Luo, Donghuan Qin, Wei Xu, Dan Wang, and Lintao Hou. "Efficient Nanocrystal Photovoltaics with PTAA as Hole Transport Layer." Nanomaterials 12, no. 17 (September 3, 2022): 3067. http://dx.doi.org/10.3390/nano12173067.
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The power conversion efficiency (PCE) of solution-processed CdTe nanocrystals (NCs) solar cells has been significantly promoted in recent years due to the optimization of device design by advanced interface engineering techniques. However, further development of CdTe NC solar cells is still limited by the low open-circuit voltage (Voc) (mostly in range of 0.5–0.7 V), which is mainly attributed to the charge recombination at the CdTe/electrode interface. Herein, we demonstrate a high-efficiency CdTe NCs solar cell by using organic polymer poly[bis(4–phenyl)(2,4,6–trimethylphenyl)amine] (PTAA) as the hole transport layer (HTL) to decrease the interface recombination and enhance the Voc. The solar cell with the architecture of ITO/ZnO/CdS/CdSe/CdTe/PTAA/Au was fabricated via a layer-by-layer solution process. Experimental results show that PTAA offers better back contact for reducing interface resistance than the device without HTL. It is found that a dipole layer is produced between the CdTe NC thin film and the back contact electrode; thus the built–in electric field (Vbi) is reinforced, allowing more efficient carrier separation. By introducing the PTAA HTL in the device, the open–circuit voltage, short-circuit current density and the fill factor are simultaneously improved, leading to a high PCE of 6.95%, which is increased by 30% compared to that of the control device without HTL (5.3%). This work suggests that the widely used PTAA is preferred as the excellent HTL for achieving highly efficient CdTe NC solar cells.
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Sun, Yujian, Yongcao Zhang, Yuxin Li, and Yilin Li. "Self-Absorption Analysis of Perovskite-Based Luminescent Solar Concentrators." Electronic Materials 2, no. 4 (December 10, 2021): 545–52. http://dx.doi.org/10.3390/electronicmat2040039.
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Luminescent solar concentrators (LSCs) are considered promising in their application as building-integrated photovoltaics (BIPVs). However, they suffer from low performance, especially in large-area devices. One of the key issues is the self-absorption of the luminophores. In this report, we focus on the study of self-absorption in perovskite-based LSCs. Perovskite nanocrystals (NCs) are emerging luminophores for LSCs. Studying the self-absorption of perovskite NCs is beneficial to understanding fundamental photon transport properties in perovskite-based LSCs. We analyzed and quantified self-absorption properties of perovskite NCs in an LSC with the dimensions of 6 in × 6 in × 1/4 in (152.4 mm × 152.4 mm × 6.35 mm) using three approaches (i.e., limited illumination, laser excitation, and regional measurements). The results showed that a significant number of self-absorption events occurred within a distance of 2 in (50.8 mm), and the photo surface escape due to the repeated self-absorption was the dominant energy loss mechanism.
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Levchuk, I., C. Würth, F. Krause, A. Osvet, M. Batentschuk, U. Resch-Genger, C. Kolbeck, et al. "Industrially scalable and cost-effective Mn2+ doped ZnxCd1−xS/ZnS nanocrystals with 70% photoluminescence quantum yield, as efficient down-shifting materials in photovoltaics." Energy & Environmental Science 9, no. 3 (2016): 1083–94. http://dx.doi.org/10.1039/c5ee03165f.
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Arumugam, Gowri Manohari, Santhosh Kumar Karunakaran, Raquel E. Galian, and Julia Pérez-Prieto. "Recent Progress in Lanthanide-Doped Inorganic Perovskite Nanocrystals and Nanoheterostructures: A Future Vision of Bioimaging." Nanomaterials 12, no. 13 (June 21, 2022): 2130. http://dx.doi.org/10.3390/nano12132130.
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All-inorganic lead halide perovskite nanocrystals have great potential in optoelectronics and photovoltaics. However, their biological applications have not been explored much owing to their poor stability and shallow penetration depth of ultraviolet (UV) excitation light into tissues. Interestingly, the combination of all-inorganic halide perovskite nanocrystals (IHP NCs) with nanoparticles consisting of lanthanide-doped matrix (Ln NPs, such as NaYF4:Yb,Er NPs) is stable, near-infrared (NIR) excitable and emission tuneable (up-shifting emission), all of them desirable properties for biological applications. In addition, luminescence in inorganic perovskite nanomaterials has recently been sensitized via lanthanide doping. In this review, we discuss the progress of various Ln-doped all-inorganic halide perovskites (LnIHP). The unique properties of nanoheterostructures based on the interaction between IHP NCs and Ln NPs as well as those of LnIHP NCs are also detailed. Moreover, a systematic discussion of basic principles and mechanisms as well as of the recent advancements in bio-imaging based on these materials are presented. Finally, the challenges and future perspectives of bio-imaging based on NIR-triggered sensitized luminescence of IHP NCs are discussed.
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Shan, Feng, and Tong Zhang. "Shape and Size Dependent Light Absorption Enhancement of Silver Nanostructures in Organic Solar Cells." Solid State Phenomena 266 (October 2017): 90–94. http://dx.doi.org/10.4028/www.scientific.net/ssp.266.90.
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Metal nanoparticles (MNPs) induced light absorption enhancement using for the improvement of power conversion efficiency of organic solar cells (OSCs) is a new research direction in photovoltaics. However, the device performance influence of the shape and size of MNPs has not been well investigated. In this paper, we focused on the comparison study of the optical absorption enhancement between silver nanospheres (Ag-NSs) and silver nanocubes (Ag-NCs) which are embedded in the active layer of OSCs using finite element method (FEM) simulation. Influence of the structural parameters, including the size and shape of nanoparticels, and their relative distance are systematically discussed. The results indicated that the light absorption enhancement employing Ag-NCs is much higher than that of Ag-NSs in the 300–800 nm wavelength range. Meantime, once the distance between the adjacent nanoparticles is well controlled, the optimal absorption enhancement factor of OSCs can be obtained. As the scattering cross-section of Ag-NCs is much higher than that of Ag-NSs over a broad wavelength range, the optimized light enhancement of Ag-NCs reaches 19 % which is 1.26 times higher than that of Ag-NSs.
Dissertations / Theses on the topic "Photovoltaics - NCs"
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Silva, Cristiano Crisostomo da. "Geração distribuída com sistemas fotovoltaicos e a qualificação profissional: uma proposta de curso pós-técnico e potencial de aplicação nas ETECS." Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/106/106131/tde-12012018-134431/.
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O crescimento e o desenvolvimento do Brasil demandam novas fontes de energia, dentre as quais destaca-se a energia solar fotovoltaica, mas para que esse acréscimo aconteça de forma organizada e segura, faz-se necessária a criação de cursos para a formação e qualificação técnica para as boas práticas de manuseio, instalação e manutenção dos sistemas. O ensino profissionalizante é um dos mais importantes vetores de desenvolvimento e aplicação das áreas tecnológicas e deve acompanhar, de maneira contínua, a evolução da tecnologia do trabalho. Este trabalho apresenta uma análise para uma proposta de criação de curso de especialização pós-técnica de nível médio, para preparar os profissionais, de forma que eles possam atuar no mercado com a segurança, confiabilidade e qualidade necessárias para que a geração de eletricidade a partir da conversão fotovoltaica atenda aos anseios da sociedade brasileira. As Escolas Técnicas Estaduais (Etec) do Governo do Estado de São Paulo são avaliadas para receber o curso proposto nesta dissertação.The growth and development of Brazil demands new sources of energy, among which we highlight the photovoltaic solar energy. But for this increase happens in an organized and safe manner, it is necessary to create courses for training and technical qualification to good handling practices, installation and maintenance of systems. This work presents an analysis for a proposal for mid-level post- technical specialization course to prepare the way professionals that they can act in the market with the necessary security, reliability and quality so that generation of electricity from the photovoltaic conversion fulfill the yearnings of Brazilian society. Public technical school (Etec) of Sao Paulo\'s State Government are evaluated to offer that proposed course at this dissertation.
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Rodrigues, Mauro Fonseca. "Instalação de microgeração distribuída com fonte fotovoltaica nas estações de telecomunicações." Universidade Federal de Santa Maria, 2013. http://repositorio.ufsm.br/handle/1/8528.
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This dissertation presents the feasibility study for integration of microgeneration of electricity with photovoltaic power in telecommunications stations. From the Resolution 482/2012 of ANEEL, April 2012, microgeneration (installed capacity equal to or less than 100 kW) began to have the capacity considered in the reckoning power of the Brazilian electric system. As the Brazilian telecommunications system is present in all locations with more than 100 residents there is the possibility of creating a network of distributed micro generation, using the similarities between these two systems, telecommunications and power generation using photovoltaic source. For this, there is a need to analyze the generation capacity in contrast to the electricity consumption of the telecommunications stations. After, was carried out the application of concepts of Economic Engineering and Simplex Method of Linear Programming to evaluate the proposed system on the financial feasibility, considering the energy saving and some scenarios sale of energy used for the distribution system of electric power of the local concessionaire. From these analyzes was made possible to verify that the system proved to be attractive both for its assessment of Engineering Economy, as the Simplex Method, proving that its application can bring benefits to telecommunications companies and distribution network that will have less load to cater. However, the sale of energy from microgeneration this may decrease the reliability of the telecommunications system and therefore is not recommended.Esta dissertação apresenta o estudo de viabilidade para inserção de microgeração de energia elétrica com fonte fotovoltaica nas estações de telecomunicações. A partir da Resolução 482/2012 da Agência Nacional de Energia Elétrica (ANEEL), de abril de 2012, a microgeração (até 100 kW de potência instalada) passou a ter sua capacidade considerada no cômputo de energia do sistema elétrico brasileiro. Como o sistema brasileiro de telecomunicações está presente em todas as localidades com mais de 100 habitantes há a possibilidade de criar uma rede de microgeração distribuída, utilizando as similaridades entre esses dois sistemas: telecomunicações e geração de energia com fonte fotovoltaica. Para isso, verificou-se a necessidade de analisar a capacidade de geração em contrapartida com o consumo de energia elétrica das estações de telecomunicações. Após, realizou-se a aplicação de conceitos da Engenharia Econômica e o Método Simplex da Programação Linear para avaliar o sistema proposto quanto à viabilidade financeira, considerando a economia de energia e alguns cenários de venda desta energia produzida para o sistema de distribuição de energia elétrica da concessionária local. A partir destas análises efetuadas foi possível verificar que o sistema mostrou-se atrativo, tanto pela avaliação da Engenharia Econômica, quanto pelo Método Simplex, comprovando que sua aplicação pode trazer benefícios às empresas de telecomunicações e à rede de distribuição de Baixa Tensão que terá menos carga para atender. No entanto, a venda de energia a partir desta microgeração pode diminuir a confiabilidade do sistema de telecomunicações e, portanto, não é recomendada.
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Mariano, Juliana D’Angela. "Análise do potencial da geração de energia fotovoltaica para redução dos picos de demanda e contribuição energética nas edificações da UTFPR em Curitiba." Universidade Tecnológica Federal do Paraná, 2017. http://repositorio.utfpr.edu.br/jspui/handle/1/2585.
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CAPESA preocupação em alcançar o desenvolvimento sustentável está cada vez mais presente na construção civil, sendo este o setor que mais contribui com os maiores níveis de emissões de gases de efeito estufa, devido ao grande consumo de energia e recursos naturais. Adicionalmente, os edifícios despendem de uma grande quantidade energética para aplicações cotidianas e em muitos países, as fontes são provenientes de fontes não-renováveis, causando dependência de combustíveis fósseis e consequentemente elevação nos índices de emissões de CO2. Portanto, as “transições de sustentabilidade” mediante a aplicação de novos sistemas de energia renováveis, os quais apresentam emissões reduzidas, como por exemplo, a energia solar fotovoltaica, viabilizam essa mudança. Essa fonte de energia está cada vez mais presente na matriz energética mundial, seja pela aplicação de usinas fotovoltaicas de grande porte ou por meio de usinas geradoras de mini e microgeração incorporada às edificações, atuando como geração distribuída inserida no meio urbano. Neste sentido, este trabalho tem por objetivo contribuir com redução da demanda, com a eficiência energética e a quantificação das emissões de CO2 equivalente que podem ser evitadas com a energia gerada, por meio da utilização da energia fotovoltaica na UTFPR – câmpus Curitiba. A metodologia consiste na análise dos parâmetros de irradiação local horizontal e inclinada coletados por meio do portal do INMET, do Atlas Brasileiro de Energia Solar e do Piranômetro da UTFPR para aplicação do software Radiasol. Por sua vez, efetuouse o estudo do perfil de cargas da instituição, a fim de identificar os momentos de maiores consumo e demanda por energia elétrica, através da seleção de dias típicos elencados no decorrer do ano. A análise das coberturas possibilitou o levantamento de áreas disponíveis e análise de sombreamento, e através dos dados gerados pelos Sistemas Fotovoltaicos Conectados à Rede existentes foram elaborados cenários, objetivando a contribuição energética do câmpus. Por fim, foram calculados os níveis de penetração energéticos, bem como o fator efetivo de capacidade de carga, quantificando o aumento da capacidade disponível da rede elétrica atribuída à geração fotovoltaica e as respectivas emissões evitadas. Os resultados obtidos mostram que a UTFPR - câmpus Curitiba apresenta um vasto potencial para a geração de energia fotovoltaica, sendo que a instituição poderia alocar um sistema com potência instalada total de 3,25 MW, e gerar um total anual de energia de 4,37 GWh. Com relação ao nível de penetração energético total calculado, obteve-se 489,97%, o que significa a ocorrência de injeção do excedente de energia fotogerada no sistema elétrico. Pode-se concluir que além da possibilidade de redução de custos com energia elétrica, existiria uma redução significativa nas emissões de GEE’s referentes ao cálculo de CO2 podendo evitar a emissão de 284,43 tCO2 ao ano.
The concern of achieving sustainable development is increasingly present in civil construction, which is the sector that shows the highest levels of greenhouse gas emissions due to its high consumption of energy and natural resources. Buildings use a large amount of energy in their day-to-day use, and in many countries this energy comes from non-renewable sources, causing dependence on fossil fuels and consequently increasing CO2 emissions."Sustainable transitions" make change possible through the application of new renewable energy systems, which present reduced emissions, e.g. solar photovoltaic energy. This energy source is increasingly present in the global energy matrix, both in large-scale photovoltaic plants and smalland micro-generation incorporated into buildings, acting as distributed generation in urban environments. The objective of this thesis is to contribute to a reduction in demand, with energy efficiency and to the quantification of equivalent CO2 emissions that could be avoided with energy generated through the use of photovoltaic energy at UTFPR’s Curitiba campus. The methodology consists of the analysis of horizontal and inclined local irradiation parameters collected through the INMET portal, the Brazilian Solar Energy Atlas and the piranometer at UTFPR, and in the application of the software Radiasol. The study of the load profile of the institution was carried out in order to identify periods of greater consumption and demand for electric energy, through the selection of typical days during the year. The analysis of the coverages allowed the survey of available areas and a shading analysis. Through the data generated by the existing grid-connected photovoltaic system, scenarios were elaborated to model the energy contribution of the three campus. Finally, the energy penetration levels and the effectiveness factor of the load capacity were calculated quantifying the increase of the available capacity of the electricity grid, attributed to the photovoltaic generation, as well as the respective emissions avoided. The results show that the Curitiba campus of UTFPR have a vast potential for the generation of photovoltaic energy, and the institution could allocate a system with a total installed power of 3.25 MW, generating an annual total of 4.37 GWh of energy. The calculated total energy penetration level of 489.97% was obtained, which implies the injection of a surplus of photo-generated energy into the electric system. It can be concluded that besides the possibility of reducing electricity costs, there would be a significant reduction in GHG emissions calculated at 284.43 tCO2 per year.
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Duarte, João Gomes. "Viabilidade do investimento em miniprodução fotovoltaica nas obras de requalificação dos edifícios escolares públicos - contributo para NZEB (Nearly Zero Energy Building)." Master's thesis, Instituto Superior de Ciências Sociais e Políticas, 2012. http://hdl.handle.net/10400.5/5130.
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Trabalho de projeto para obtenção de grau de Mestre em Administração Pública – Especialização em Administração da EducaçãoEm 2007, foi iniciado o programa de modernização e requalificação das escolas Básicas e Secundárias Portuguesas, levada a cabo pela empresa pública Parque Escolar. Na sua maioria, as obras consistem em requalificar os espaços existentes e construir um novo edifício aglutinador das infraestruturas necessárias ao bom funcionamento das instituições. Ao aumentar a área construída e ao dotar os edifícios de melhores condições de utilização, como luminosidade, mais equipamento, climatização dos espaços, novas acessibilidades, o consumo energético dispara para valores nunca antes atingidos. Paralelamente, o custo da energia sofre um aumento sem precedentes em virtude do aumento da taxa de IVA de 6% para 23%. Uma vez que para aproximar as escolas requalificadas do conceito NZEB (Nearly Zero Energy Building) não chega implementar medidas de poupança de energia, este trabalho aponta uma solução economicamente viável para a produção sustentável de energia, através da tecnologia fotovoltaica, tornando o edifício produtor da sua própria energia, seguindo as diretivas da mais recente legislação nacional e europeia. Este estudo vem na sequência do projeto de modernização e requalificação da Escola Secundária Rafael Bordalo Pinheiro, em Caldas da Rainha, cujas conclusões se podem aplicar a qualquer edifício a nível nacional, tendo em mente que será necessário efetuar um ajuste nos cálculos em função do tipo de edifício/condições de instalação e localização geográfica.
In 2007 a modernization and renovation programme was started in the Portuguese Basic and Secondary schools, through the public enterprise Parque Escolar. The programme aims to renovate the existing buildings and to construct new ones in order to comprise the necessary infrastructures to the proper functioning of the institution. As the area built increases and the buildings are provided with better conditions such as more luminosity, more equipment, air-conditioning, new accessibilities, the power consumption rises to record levels. Meanwhile the cost of energy reaches an unprecedented level due to the increase in standard rate of VAT – from 6% to 23%. As the implementation of energy efficiency measures is not enough to allow the renovated schools to come close to the concept of NZEB (Nearly Zero Energy Building), this work points out an economically viable solution which aims to the production of sustainable energy through the photovoltaic system, so that it can be possible for the building to supply its own energy, following the most recent Portuguese and European legislation. This study is about the modernization and renovation of “Rafael Bordalo Pinheiro Secondary School”; however, the study conclusions may be implemented in any public building, considering that necessary adjustments will have to be made according to both the characteristics of the building itself and and its geographical location.
Book chapters on the topic "Photovoltaics - NCs"
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Wang, Zihu, Zhengsheng Liu, Yuanhong Liu, Hongqing Qu, Xiaohui Han, and Xiaoyong Chen. "Research on Leakage Recognition Method of Photovoltaic Connected to Distribution Network Based on NCA and SSA-KELM." In Lecture Notes in Electrical Engineering, 300–307. Singapore: Springer Nature Singapore, 2023. http://dx.doi.org/10.1007/978-981-99-0451-8_30.
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Ofori-Ntow Jnr, Eric, Yao Yevenyo Ziggah, Mehdi Rahmani-Andebili, Maria Joao Rodrigues, and Susana Relvas. "A Novel Three-Stage Short-Term Photovoltaic Prediction Approach Based on Neighborhood Component Analysis and ANN Optimized with PSO (NCA-PSO-ANN)." In Applications of Artificial Intelligence in Planning and Operation of Smart Grids, 75–95. Cham: Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-030-94522-0_3.
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M. Khayyat, Maha. "Semiconductor Epitaxial Crystal Growth: Silicon Nanowires." In 21st Century Nanostructured Materials - Physics, Chemistry, Classification, and Emerging Applications in Industry, Biomedicine, and Agriculture. IntechOpen, 2022. http://dx.doi.org/10.5772/intechopen.100935.
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The topic of nanowires is one of the subjects of technological rapid-progress research. This chapter reviews the experimental work and the advancement of nanowires technology since the past decade, with more focus on the recent work. Nanowires can be grown from several materials including semiconductors, such as silicon. Silicon is a semiconductor material with a very technological importance, reflected by the huge number of publications. Nanowires made of silicon are of particular technological importance, in addition to their nanomorphology-related applications. A detailed description of the first successfully reported Vapor–Liquid–Solid (VLS) 1-D growth of silicon crystals is presented. The bottom-up approach, the supersaturation in a three-phase system, and the nucleation at the Chemical Vapor Deposition (CVD) processes are discussed with more focus on silicon. Positional assembly of nanowires using the current available techniques, including Nanoscale Chemical Templating (NCT), can be considered as the key part of this chapter for advanced applications. Several applied and conceptional methods of developing the available technologies using nanowires are included, such as Atomic Force Microscopy (AFM) and photovoltaic (PV) cells, and more are explained. The final section of this chapter is devoted to the future trend in nanowires research, where it is anticipated that the effort behind nanowires research will proceed further to be implemented in daily electronic tools satisfying the demand of low-weight and small-size electronic devices.
Conference papers on the topic "Photovoltaics - NCs"
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Garcia Gonzalez, Alexis. "Industrial Solar Simulator Calibrator based on special solar module." In NCSL International Workshop & Symposium. NCSL International, 2021. http://dx.doi.org/10.51843/wsproceedings.2021.14.
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Mexico is currently emerging in the photovoltaic manufacturing market due to favorable geographical conditions like 5.5 hours of sun every day (5000W/m2) and a strategic commercial partner (USA) for exportation of photovoltaic products, therefore a gradual advance in the photovoltaic field as a source of clean energy generation in Mexico is inevitable, this causes a need to classify solar simulators located in photovoltaic manufacturing facilities across the whole country. The construction of a standard for the classification of large area solar simulators in non- uniformity irradiance (MMNU) was achieved, considering specifications of the international standards IEC90604-9 and IEC90604-2. The procedure for using this MMNU substantially improves the classification time of a large area solar simulation and its versatility of use in an industrial environment, resulting in suitable on-site measurements. The MMNU is composed of six electronic reading circuits and 36 cells which are connected individually, it can generate an irradiance map up to 72 regions and the measurement uncertainty within the operating temperature conditions of 29 C to 31 C was 1.1 % using the mathematical expression for non-uniformity in the standard IEC90604-9. Various strategies have been outlined to reduce the measurement uncertainty of the entire system, like reducing its thermal drift during measurement and improving the measurement uncertainty in electrical voltage by creating a new electronic reading module that would include a more robust microcontroller and A/D converter with higher resolution.
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Oleschuk, Valentin. "Algorithms of Overmodulation Regulation of Neutral Clamped Inverters for Photovoltaics." In 12th International Conference on Electronics, Communications and Computing. Technical University of Moldova, 2022. http://dx.doi.org/10.52326/ic-ecco.2022/el.04.
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This manuscript presents results of study and research of synchronous adjustment in the overmodulation control zone of three neutral-clamped inverters (NCIs) of the specific configuration of three-phase grid-connected photovoltaic system. It has been proved, that the corresponding modification of techniques and algorithms of pulsewidth modulation (PWM) for control of NCIs, assure symmetry and advanced harmonic composition of inverter-side winding voltage of multi-winding power transformer, thereby helping to reduce losses in windings of the transformer, and to improve the efficiency of photovoltaic installations.
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Volz, K., A. Szesney, C. Jurecka, I. Nemeth, O. Rubel, W. Stolz, E. Welser, E. Oliva, F. Dimroth, and A. W. Bett. "Development and optimization of a 1 eV (GaIn)(NAs) solar cell." In 2009 34th IEEE Photovoltaic Specialists Conference (PVSC). IEEE, 2009. http://dx.doi.org/10.1109/pvsc.2009.5411194.
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Yang, Steven S. L. "Calibration of Programmable Loads." In NCSL International Workshop & Symposium. NCSL International, 2017. http://dx.doi.org/10.51843/wsproceedings.2017.14.
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The Standards and Calibration Laboratory (SCL) in Hong Kong has developed a system for the calibration of programmable loads. A programmable load is commonly used to emulate DC or AC loads required to perform functional tests of batteries, photovoltaic cells, power supplies, inverters and transformers. In recent years, programmable loads have more new applications such as electric vehicle testing and regenerative energy system testing. Load regulation test, battery discharge measurement and transient tests can be automated by programmable loads, which load changes for these tests can be made without introducing significant switching transient. Programmable load settings and read back accuracy for constant current mode, constant resistance mode, constant voltage mode, constant power mode and power factor modele loads can also be tested. Details of the proposed AC and DC programmable load calibration system developed at SCL are described in the paper.
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Kandlakunta, Praneeth, Lei Pan, Lei R. Cao, Matthew Van Zile, Xuezeng Dai, Jinsong Huang, and John McClory. "Solar Photovoltaic Devices as Radiation Sensors for Post-detonation Nuclear Forensics." In 2020 IEEE Nuclear Science Symposium and Medical Imaging Conference (NSS/MIC). IEEE, 2020. http://dx.doi.org/10.1109/nss/mic42677.2020.9507766.
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Esposito, Daniel V. "Estimating solar energy requirements to meet U.S. energy needs: an outreach event." In NCSL International Workshop & Symposium. NCSL International, 2014. http://dx.doi.org/10.51843/wsproceedings.2014.22.
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This paper describes an educational outreach activity based on the following question: How large of an area must be covered with solar photovoltaic panels in order to meet U.S. energy demand? This activity is organized around a flexible structure that can be modified for the target audience (ranging from middle school students to adults) and contains ample opportunities for hands-on participation. After providing an overview of the activity and objectives, we describe the supplies needed to carry out this activity and guidelines for selecting and using them. Materials/supply costs for this activity are around $100-$250 but can be as low as $30. A detailed description of a baseline lesson plan is provided, and optional, add-on activities are described. The activity can be completed in as little as 15 minutes and extended to as long as several hours. Key learning objectives are to introduce the audience to the basic operating principles of solar cells, measure the performance of solar cells, and apply the metric system and order-of-magnitude reasoning skills to the above-stated question.
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Singh, Vikas Pratap, B. Ravindra, Vivek Vijay, and M. Siddhartha Bhatt. "Forecasting of 5MW solar photovoltaic power plant generation using generalized neural network." In 2015 39th National Systems Conference (NSC). IEEE, 2015. http://dx.doi.org/10.1109/natsys.2015.7489107.
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Tsai, Min-An. "Introduction to the Status of Interlaboratory Comparison on Reference Photovoltaic Cell Calibration at Center for Measurment Standards in Taiwan." In NCSL International Workshop & Symposium. NCSL International, 2016. http://dx.doi.org/10.51843/wsproceedings.2016.46.
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Proficiency testing is one of the ways to evaluate the participant performance against pre-established criteria by means of interlaboratory comparisons. Center for Measurement Standards / Industrial Technology Research Institute (CMS/ITRI) has been committed to measurement technologies and statistical engineering. Thus, CMS has established its renowned reputation in metrology in Taiwan. Quality Engineering Department (QED) which belongs to Measurement Standards & Legal Metrology Division at CMS/ITRI is one of the designated organizations by Taiwan Accreditation Foundation (TAF) to hold proficiency testing in calibration field and act as the pilot for this interlaboratory comparison. For the photovoltaic (PV) field, the key quantity in the calibration of reference PV cells or modules is the short-circuit current of the device generated by a reference solar radiation with 1 kW m-2 total irradiance and with IEC 60904-3 AM1.5G reference solar spectral irradiance distribution. This paper introduces the status of interlaboratory comparison on primary reference solar cell calibration, including selection of the reference laboratory and assigned value, statistical analysis on comparative results, and criteria for performance evaluation, etc. The comparison includes one reference laboratory and two participating laboratories individually belonging to AIST,CMS/ITRI and FMI. The calibration method is conformed to IEC 60904-4:2009. En numbers are used as the performance statistics described in ISO/IEC 17043:2010.
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Sadati, S. M. Sajed, Elham Jahani, and Onur Taylan. "Technical and Economic Analyses for Sizing PV Power Plant With Storage System for METU NCC." In ASME 2015 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2015. http://dx.doi.org/10.1115/imece2015-50959.
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The use of renewable energy with storage systems is particularly important in small and unreliable grids, such as islands. This paper reports sizing of a photovoltaic (PV) power plant with storage system for Middle East Technical University Northern Cyprus Campus through technical and economic analyses. PV system was modeled considering fixed tilted, one-axis and two-axis tracking systems using hourly data. Energy storage system was included in the model to overcome the temporal mismatch between the electricity demand of the campus and the electricity supplied by the PV system. The reduction in CO2 emissions by deploying these systems was studied. The results showed that although it would not be economically feasible to meet the entire demand of the campus, a PV system of 4.5 MW with 15 MWh of storage size would generate enough electricity to meet the demand for 83% of the time in a year, yielding the cost of 0.25 USD/kWh.
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Goren, Deniz, and Onur Taylan. "P50/P90 Analysis of a Solar Photovoltaic Plant in METU NCC Using the Empirical Method." In 2020 2nd International Conference on Photovoltaic Science and Technologies (PVCon). IEEE, 2020. http://dx.doi.org/10.1109/pvcon51547.2020.9757770.
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