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Copyright of GeSec: Revista de Gestao e Secretariado is the property of Sindicato das Secretarias e Secretarios do Estado de Sao Paulo (SINSESP) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of GeSec: Revista de Gestao e Secretariado is the property of Sindicato das Secretarias e Secretarios do Estado de Sao Paulo (SINSESP) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Exact Sciences is the property of Master Editora and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Brasileira de Engenharia Agricola e Ambiental - Agriambi is the property of Revista Brasileira de Engenharia Agricola e Ambiental and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Dilemas Contemporáneos: Educación, Política y Valores is the property of Dilemas Contemporaneos: Educacion, Politica y Valores and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Bird populations are declining globally. Wind and solar energy can reduce emissions of fossil fuels that drive anthropogenic climate change, yet renewable‐energy production represents a potential threat to bird species. Surveys to assess potential effects at renewable‐energy facilities are exclusively local, and the geographic extent encompassed by birds killed at these facilities is largely unknown, which creates challenges for minimizing and mitigating the population‐level and cumulative effects of these fatalities. We performed geospatial analyses of stable hydrogen isotope data obtained from feathers of 871 individuals of 24 bird species found dead at solar‐ and wind‐energy facilities in California (USA). Most species had individuals with a mix of origins, ranging from 23% to 98% nonlocal. Mean minimum distances to areas of likely origin for nonlocal individuals were as close as 97 to >1250 km, and these minimum distances were larger for species found at solar‐energy facilities in deserts than at wind‐energy facilities in grasslands (Cohen's d = 6.5). Fatalities were drawn from an estimated 30–100% of species' desingated ranges, and this percentage was significantly smaller for species with large ranges found at wind facilities (Pearson's r = −0.67). Temporal patterns in the geographic origin of fatalities suggested that migratory movements and nonmigratory movements, such as dispersal and nomadism, influence exposure to fatality risk for these birds. Our results illustrate the power of using stable isotope data to assess the geographic extent of renewable‐energy fatalities on birds. As the buildout of renewable‐energy facilities continues, accurate assessment of the geographic footprint of wildlife fatalities can be used to inform compensatory mitigation for their population‐level and cumulative effects. [ABSTRACT FROM AUTHOR]

Copyright of Revista Foco (Interdisciplinary Studies Journal) is the property of Revista Foco and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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Cuba ha trabajado en el desarrollo de la energía fotovoltaica para disminuir la dependencia de los combustibles fósiles. El sector residencial ha acogido la modalidad de instalar paneles solares en los techos de sus hogares con el fin de reducir sus tarifas. La energía no consumida puede ser vendida a la red eléctrica nacional. En el estudio, a través del análisis de escenarios, con el Homer Pro, se determinó el tiempo aproximado para recuperar la inversión inicial y obtener ganancias al evaluar su viabilidad técnico-económica con el objetivo de recuperar la inversión en 7 a 8 años. Al brindarse una visión clara de cómo el estudio, al considerar las condiciones y necesidades locales, ofrece recomendaciones específicas sobre el ajuste de tarifas para incentivar la inversión en energía solar y resalta su relevancia dentro del contexto habanero, de modo que los prosumidores puedan recuperar su inversión en menor tiempo.

El comportamiento de las instalaciones solares térmicas depende de muchas variables, una de ellas es la temperatura del agua de alimentación al colector. En muchos países la temperatura del agua de alimentación a utilizar para predecir la producción de una instalación solar a largo plazo se encuentra normalizada. La temperatura del agua de red depende fuertemente de la temperatura del ambiente y del tiempo de residencia del agua en las tuberías. En este trabajo se estableció el perfil temporal de temperaturas para el agua de red en la ciudad de Resistencia, se analizó su relación con la temperatura ambiente y se calculó la fracción solar de una instalación para proveer agua caliente sanitaria en función de las evoluciones de las temperaturas. Los perfiles temporales de temperatura se ajustaron mediante una oscilación armónica de periodo anual, con una media de 4 ºC superior a la temperatura ambiente y una amplitud de 7 ºC, con el mínimo para el mes de julio.

The purpose of this work was to analyze the main advantages and disadvantages of solar photovoltaic energy in Brazil and in the five countries that most produce it. For that, we conducted a systematic review in scientific papers, considering only the environmental sciences field, published in free-access databases in the period from 2016 to 2021, with Qualis Capes (evaluation - 2013 to 2016) between the A1 and B2 strata, written in Portuguese and English. We selected 3,026 papers, of which 62 met the research criteria. We identified 26 advantages, and the most cited were: absence/low emission of greenhouse gases; possibility of use in remote areas, alternative locations, and for different economic activities; high cost-effectiveness considering the life cycle; diversification of the electric matrix, and the fact that it is a clean, abundant, and reliable energy resource. We identified 18 disadvantages, and the most cited were: high initial cost; need to increase appropriate regulations for non-economic barriers that may hinder the effectiveness of policies and support schemes; lack of business models for private sector financing; dependence on climate conditions/operation for a limited period. The survey data showed that the number of citations and the amount of advantages are much higher than the disadvantages, which suggests the high potential of using solar photovoltaic energy and its socio-environmental and economic benefits. [ABSTRACT FROM AUTHOR]

Hydrogen as an energy vector can provide energy in applications from low to large scale and contributes to the promotion of renewable energies as low-carbon emission alternatives. This paper presents a literature review on hybrid green hydrogen systems. It was found that 23% of the articles review different methodologies and comparisons of hydrogen technologies, 15% present technical, economic and environmental analyses of hydrogen-based systems and projects. Fifty-three percent of the reviewed articles focus on artificial intelligence methodologies and use of commercial software for sizing, energy management and optimization of these models on hybrid renewable energy systems with a high focus on off-grid systems. The potential for simulation models to be developed on this topic is quite large because of the decarbonization brought by hydrogen. The models should consider additional aspects of the entire hydrogen value chain to have a complete vision of its development in Colombia, taking into account the development opportunities in the framework of different energy scenarios. [ABSTRACT FROM AUTHOR]

The usefulness and productivity of photovoltaic (PV) panels are significantly impacted by ambient and operating temperatures. However, the negative influence of hot climates on PV panel performance can be mitigated through innovative cooling techniques. This research work aims to investigate the implementation of phase change material (PCM) on the backside of solar modules to reduce panel temperature and enhance energy production. A hybrid system utilizing soy wax for cooling is applied to the rear of the panel. Comparative data have been collected on various days, and the outcomes have been analyzed. The outcomes reveal that the usage of phase change material reduced panel temperature by up to 18°C, causing a 10.89% rise in electricity generation compared to panels without cooling systems. [ABSTRACT FROM AUTHOR]

Cuba has worked on the development of photovoltaic energy to reduce dependence on fossil fuels. The residential sector has embraced the modality of installing solar panels on the roofs of their homes in order to reduce their rates. Unconsumed energy can be sold to the national electrical grid. In the study, through scenario analysis, with the Homer Pro, the approximate time to recover the initial investment and obtain profits was determined by evaluating its technical-economic viability with the objective of recovering the investment in 7 to 8 years. At provide a clear vision of how the study, when considering local conditions and needs, offers specific recommendations on adjusting tariffs to encourage investment in solar energy and highlights its relevance within the Havana context, so that prosumers can recover their investment in solar energy less time. [ABSTRACT FROM AUTHOR]

Copyright of Immaterial is the property of BAU, Centro Universitario de Diseno de Barcelona and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Iberoamericana de Estudios de Desarrollo is the property of Revista Iberoamericana de Estudios de Desarrollo and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Foco (Interdisciplinary Studies Journal) is the property of Revista Foco and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Semestre Económico is the property of Sello Editorial de la Universidad de Medellin and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Brazilian Journal of Production Engineering / Revista Brasileira de Engenharia de Produção is the property of Brazilian Journal of Production Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of GeSec: Revista de Gestao e Secretariado is the property of Sindicato das Secretarias e Secretarios do Estado de Sao Paulo (SINSESP) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

La producción de electricidad a partir de energía solar es una de las alternativas clave para abastecer de energía eléctrica a zonas rurales que no tienen acceso al sistema eléctrico nacional. En este sentido, se presenta una propuesta de implementación de un sistema solar fotovoltaico autónomo (con baterías de almacenamiento) en una comunidad de la región Lambayeque. El sistema solar fotovoltaico propuesto está compuesto por 16 paneles solares fotovoltaicos, 14 baterías de acumulación y 1 inversor de DC-AC. El proyecto evitará la liberación de 2110,40 kg CO2eq/año de emisiones de gases de efecto invernadero (GEI) al medioambiente, que de otra forma se producirán por la combustión de diésel en un motor generador eléctrico. El presente documento recomienda que los gobiernos regionales repliquen la implementación de sistemas solares fotovoltaicos autónomos que aprovechen la disponibilidad del recurso solar en otras zonas del Perú.

El aprovechamiento de la energía solar como una fuente de energía renovable depende de nuestra capacidad de estimar la cantidad de energía que procede del sol. Por esta razón, numerosos estudios han sido propuestos con la intención de establecer métodos para el pronóstico de la energía recibida del cielo, por lo que fue necesario estandarizar el amplio rango de cielos del mundo por medio del estándar ISO 15469 CIE 011/2003. Este trabajo ha comparado los resultados de la clasificación de cielos CIE obtenidos por medio de dos métodos de clasificación: por comparación de las funciones de gradación e indicatriz teóricas y los grupos homónimos observados y por comparación del error medio cuadrático RMSE entre las distribuciones de luminancia de la bóveda celeste y las luminancias teóricas definidas por el estándar CIE. Los datos de distribución de luminancias empleados proceden de imágenes de alto rango dinámico (HDR). Se ha comprobado que aproximadamente la mitad de las imágenes analizadas coinciden en la clasificación, no obstante, se ha observado que un gran porcentaje de las imágenes que no muestran coincidencias difieren un máximo de dos tipos de clasificación.

Este trabajo analiza los incentivos fiscales al autoconsumo de energía solar fotovoltaica, en el contexto europeo y español de transición energética y del incremento de precios de la electricidad, con un enfoque multidisciplinar. Su principal objetivo es valorar si estos incentivos son o no necesarios y suficientes, examinando la actual regulación española y de la Unión Europea. En el análisis realizado, se tienen en cuenta experiencias del Derecho comparado y se consideran, especialmente, los objetivos de sostenibilidad medioambiental, económica y financiera, así como los principios de igualdad, capacidad económica y progresividad. Se llega a la conclusión de que es necesario revisar la regulación vigente y plantear si el conjunto regulatorio consigue su finalidad de una manera justa y efectiva.

Sustainable energy economics in Latin America has become relevant due to the region’s dependence on the oil market and the disruption caused by the COVID-19 pandemic. A systematic review of the ten major economies in the region based on gross domestic product is conducted. We primarily analyze production performance of hydro, wind, and solar energies, in terms of total gigawatt hours produced, current participation levels in energy matrices, and total installed capacity. Current and future trends and legal frameworks for each technology and country are discussed. Our analyses indicate that Latin America and the Caribbean can potentially increase the usage of renewable energy sources given a plethora of natural resources, favorable geographical and climatic conditions, and existing large-scale hydro installations to counteract the inconsistency of wind and solar projects. Therefore, governments in the region must overhaul sustainable policies to increase awareness and reduce energy dependence on foreign powers.

O aumento do consumo de energia elétrica na sociedade é constante. O homem torna-se cada vez mais dependente de eletroeletrônicos além disso, o mundo enfrenta um quadro de mudanças climáticas que afetam o desempenho rentável das hidrelétricas, principal fonte de energia elétrica do Brasil, enfatizando a necessidade de buscar outra fonte de energia renovável, como a energia solar. Para promover um ambiente que impulsione a melhor eficiência deste tipo de energia, torna-se essencial o planejamento territorial das cidades e estados brasileiros pautado em políticas públicas específicas. Este trabalho tem como objetivo avaliar a implementação do planejamento energético nas políticas públicas brasileiras. Através de pesquisa quali-quantitativa, realizou-se primeiramente o levantamento de dados de irradiação solar no território brasileiro, enfatizando o Estado de Santa Catarina e de investimentos no setor fotovoltaico realizados na área de estudo, desenvolveu-se uma análise sobre a Lei de Ordenamento Territorial do Município de Joinville, SC. Desta forma, concluiu-se que o país ainda não apresenta planos ou políticas eficientes que preparem o desenho urbano das cidades para otimizar a geração eficiente de energia solar.

An ecological and standardized process was developed for the production of garlic powder in the agricultural sector of the Arequipa region to obtain a final product with optimal organoleptic characteristics in color, smell and flavor; compared to traditional and manual processing as is normally done. This process is divided into four units: raw material preparation, raw material processing, obtaining garlic powder and obtaining compost from the solid residues of the process. It is proposed to obtain an eco-friendly process with unified procedures through the use of its solid waste, the use of solar energy and the use of measurement instruments that will facilitate the monitoring of optimal production values identified in each unit operation through the installation of points of control. The results ensure the obtaining of garlic powder that preserves its properties and benefits by continuously taking advantage of its residues. [ABSTRACT FROM AUTHOR]

Um dos principais desafios no desenvolvimento de centros eletroprodutores renováveis prende-se com a sua localização. Essa decisão está intrinsecamente ligada à necessidade de equilibrar a disponibilidade de recursos com outros usos. No atual contexto de transição energética, a produção de energia renovável terá de crescer significativamente para a descarbonização do sistema elétrico. Em Portugal, as metas do Plano Nacional Energia e Clima (PNEC) determinam que a capacidade instalada de energia solar fotovoltaica existente até 2022 tem de crescer cerca de oito vezes até ao final da década. Antecipam-se por isso significativas transformações territoriais e alterações nas paisagens com uma crescente procura por solo que gerará competição territorial e impactes nos ecossistemas. Este estudo apresenta uma proposta de identificação de localizações para a implantação de infraestruturas de produção de energia solar fotovoltaica em linha com princípios de sustentabilidade e posterior avaliação dos projetos previstos. A análise foi desenvolvida em duas fases: a primeira com recurso a uma análise multicritério (AMC) em sistemas de informação geográfica (SIG) em que se desenvolveu um índice espacial que classifica o território continental português pela aptidão a uma localização sustentável para centrais solares fotovoltaicas; a segunda, que identificou a localização dos projetos previstos (centrais licenciadas e a aguardar licenciamento com potência =1 MW) numa ótica de monitorização ex-ante, pelo cruzamento com o índice obtido. A abordagem adotada constitui um protótipo de um sistema espacial de apoio à decisão face aos desafios territoriais da produção de energia renovável. Conclui-se que a localização das propostas de futuras centrais solares foi escolhida predominantemente com base num racional técnicoeconómico, sem considerar devidamente os impactes destas infraestruturas noutras dimensões do desenvolvimento sustentável. One of the main challenges in the development of renewable energy centers is the location. This decision is intrinsically linked to the need of balancing resource availability with other uses. In the current context of energy transition, renewable energy production must increase significantly in order to decarbonize the electricity system. In Portugal, the objectives of the National Energy and Climate Plan (NECP) stipulate that the installed capacity of photovoltaic solar energy by 2022 must increase around eightfold until the end of the decade. Therefore, significant territorial transformations and landscape changes are expected, with an increasing demand for land that will generate territorial competition and impacts on ecosystems. The study presents a proposal to identify locations for the implementation of photovoltaic solar energy production infrastructures in line with sustainability principles and for a subsequent assessment of the proposed projects. The analysis was carried out in two phases: the first with a multicriteria analysis (MCA) in geographic information systems (GIS), in which a spatial index was developed to classify the Portuguese mainland territory according to its suitability as a sustainable location for utility-scale solar photovoltaic plants; and the second, with an ex-ante monitoring perspective, which identified the location of planned projects (plants licensed and waiting licensing with power capacity =1 MW) in relation to the obtained index. The approach constitutes a prototype of a system for spatial decision-making support for the territorial challenges of renewable energy production. We conclude that the location of future solar power plants was chosen primarily based on a technical and economic basis without considering the impact of these infrastructures on other aspects of sustainable development. [ABSTRACT FROM AUTHOR]

La investigación analizó la implementación de energía solar fotovoltaica en sectores del Ecuador con difícil acceso y/o desprovistos de servicio eléctrico, con énfasis en la amazonia ecuatoriana, basado en experiencias de países Latinoamericanos. La metodología tuvo un nivel de alcance exploratorio y descriptivo, con enfoque cualicuantitativo, no experimental de corte transversal; su enfoque cualitativo respondió a una revisión sistemática y su enfoque cuantitativo a un estudio basado en metaanálisis, de la aplicación de criterios de inclusión se obtuvo un total de 103 trabajos investigativos, cantidad reducida a 56 con la aplicación de criterios de exclusión; clasificada la información, 32 resultaron idóneos para el proceso descriptivo de revisión sistemática y 24 para metaanálisis. Al finalizar la investigación se determinó que la implementación de energía solar fotovoltaica en sectores de difícil acceso y/o desprovistos de servicio eléctrico financieramente no es viable en sectores rurales e incluso urbanos, ya que la vida útil de los paneles solares oscila entre los 10 a 25 años y la recuperación de inversión se proyecta a largo plazo (10 años), implicando con ello elevados costos y un elevado riesgo para inversionistas y el estado; por otro lado, las condiciones geofísicas de la región amazónica del Ecuador es idónea para su implantación; sin embargo, la falta de políticas públicas e incentivos que impulsen el cambio de matriz energética y consecuentemente la implementación de este y otros sistemas de energía renovable no ha sido efectivo. Por otro lado, la evaluación de impacto ambiental refleja resultados positivos, pues su implementación reduciría los niveles de contaminación y alinearía al país eficientemente a los objetivos de desarrollo sostenible (Agenda 2030).

Introducción: En Tena, la producción individual de cacao se ve limitada por problemas como: alta humedad del ambiente, ineficiente secado del fruto, contaminación (secado en carreteras), el escaso valor agregado y consumo interno. Objetivo: Evaluar la eficiencia de un sistema de secado solar directo para granos de cacao en Tena. Materiales y Métodos: Se construyó un secador solar directo de convención natural tipo carpa para un análisis experimental de secado para muestras de 5 kilogramos de cacao y evaluación de temperaturas en el sistema, velocidad de secado, humedad y eficiencia térmica. Resultados y Discusión: Durante el análisis experimental, la diferencia promedio de humedad del aire fuera y dentro del secador fue del 10 % en horas de mayor irradiación solar, en los primeros cinco días se perdió 40 % de la humedad en los granos de cacao, mientras que en los siguientes tres días se logró disminuir 7 % de la humedad. La eficiencia promedio del secador solar fue del 15,38 %. Esto indica un funcionamiento del secador de manera adecuada, los resultados obtenidos se encontraron dentro del rango del 3 % al 65 %. Conclusiones: La eficiencia del secador fue evaluada a través del secado de 5 kg de cacao fermentado, obteniéndose al final del proceso 3,72 kg de cacao con una humedad del 7 %. Los principales factores que afectan la eficiencia del secador son: la humedad relativa del sector, la radiación solar que incide sobre el secador solar y el área expuesta de cacao.

It is given to the Public Administration the possibility to interfere in Economics through direct ways and also indirectly, being public support one of the possible ways of intervention. Public support can be developed through many different ways, such as tax incentives, public funding and subventions for example. When it comes to Photovoltaic Solar Energy, it is noticeable a great interest in supporting its implementation by private initiative and in such context there are some public policies that stand out. In this context, the present study aims to describe Law number 14.300/2022, as distributed microgeneration and minigeration's legal framework, in order to verify its potential innovation measures in terms of public support when it comes to photovoltaic solar energy and also its possible modifications towards public support measures that already exist. For these purposes, the method used will be the deductive, with qualitative approach, through bibliography and documental research. [ABSTRACT FROM AUTHOR]

The study of the efficiency of photovoltaic modules in outdoor conditions allows determining their correct operation and to detect abnormal behavior. Most efficiency models developed use experimental data that are difficult to obtain as they require specialized equipment and a long measurement time under laboratory conditions to identify or adjust the model parameters. In this article, we propose a linear equation that estimates the efficiency of photovoltaic modules using irradiance and back panel temperature measurements as input variables. The main contribution is that the parameters of the proposed model can be obtained directly from the reference information (IEC61853-1 power values) without any data regression. The proposed model was validated using experimental data obtained from three different climatic zones during a whole year. The model shows the best fit to the data of four analyzed models, and its normalized root mean square deviation for all photovoltaic modules is less than 3.6%; this dispersion could be explained by the fact that the outdoor data have an uncertainty of around 3.0%. [ABSTRACT FROM AUTHOR]

There is a critical need to use the abundantly available solar energy worldwide due to the global energy crisis. The goal of this study is to demonstrate the residential use of a stirling engine powered by solar energy in Karachi, Pakistan. The design was carried out to produce a power output of 5 kW in order to address the issues with household and rural area power generating. The design was simulated using MATLAB. The use of solar energy as the engine's heat input was one of the design's key components. This allowed the engine to be built for locations with a lot of solar radiation. In regions with abundant solar energy, solar cookers, sun air warmers, and other appliances may be used. For power generation, however, the Stirling engine was chosen. Calculations of the sun intensity showed that 5 kW of Stirling engine output could be generated from 12 kW of solar electricity. The concentrator for concentrating and reflecting the incoming radiations to the Stirling engine was selected as a solar parabolic dish. This process heated the engine's working fluid, which then expanded and contracted due to thermodynamic forces to produce the engine's power strokes. [ABSTRACT FROM AUTHOR]

Introduction: In Tena, individual cocoa production is limited by problems such as: high humidity in the environment, inefficient drying of the fruit, contamination (drying on roads), low value added and internal consumption. Objective: To evaluate the efficiency of a direct solar drying system for cocoa beans in Tena. Materials and Methods: A tent-type natural convention and direct tipe solar dryer was constructed for an experimental drying analysis for 5 kg of cocoa beans and evaluation of temperatures in the system, drying speed, humidity and thermal efficiency. Results and Discussion: During the experimental analysis, the average difference in air humidity outside and inside the dryer was 10 % during the hours of higher solar irradiation, in the first five days 40 % of the humidity was lost in the cocoa beans, while in the following three days 7 % of the humidity was reduced. The average efficiency of the solar dryer was 15.38 %. This indicates an adequate operation of the dryer; the results obtained were within the range of 3 % to 65%. Conclusions: The dryer's efficiency was evaluated by drying 5 kg of fermented cocoa, obtaining at the end of the process 3.72 kg of cocoa with a humidity of 7 %. The main factors affecting the dryer's efficiency are: the relative humidity of the sector, the solar radiation that falls on the solar dryer and the exposed area of cocoa. [ABSTRACT FROM AUTHOR]

Copyright of Revista Fuentes, El Reventón Energético is the property of Universidad Industrial de Santander and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Técnica Energía is the property of Centro Nacional de Control de Energia CENACE and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Sustainable energy economics in Latin America has become relevant due to the region’s dependence on the oil market and the disruption caused by the COVID-19 pandemic. A systematic review of the ten major economies in the region based on gross domestic product is conducted. We primarily analyze production performance of hydro, wind, and solar energies, in terms of total gigawatt hours produced, current participation levels in energy matrices, and total installed capacity. Current and future trends and legal frameworks for each technology and country are discussed. Our analyses indicate that Latin America and the Caribbean can potentially increase the usage of renewable energy sources given a plethora of natural resources, favorable geographical and climatic conditions, and existing large-scale hydro installations to counteract the inconsistency of wind and solar projects. Therefore, governments in the region must overhaul sustainable policies to increase awareness and reduce energy dependence on foreign powers. [ABSTRACT FROM AUTHOR]

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Copyright of Revista Foco (Interdisciplinary Studies Journal) is the property of Revista Foco and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

RESUMO O artigo revisa o trabalho de E. Altvater lidando com os desafios do esgotamento ambiental para a sobrevivência da humanidade. Mostra a lógica de sua estrutura analítica, construída para demonstrar sua tese central: os crescentes problemas ambientais são inerentes ao desenvolvimento do capitalismo, levando a uma nítida divisão entre um pequeno número de países com altos níveis de consumo de recursos naturais e os demais, pobres, destinados a desempenhar um papel de reservas de recursos naturais para os primeiros. O artigo discute a validade da hipótese deste modelo analítico. Assume como verdadeiro apenas o primeiro, sobre a impossibilidade de difundir para todo o mundo os padrões de produção e consumo euro-americanos sem causar um desastre ambiental. Os outros são vistos como carentes de evidências empíricas ou de argumentos mais sólidos.

O sol é fonte de luz e de vida, e a energia que emana dele é praticamente inesgotável, podendo ser usada de modo direto por meio de uma usina solar fotovoltaica. O Nordeste do Brasil possui uma alta e quase uniforme densidade de irradiação solar. Assim, a instalação de uma usina fotovoltaica ligada à rede no Instituto Federal de Educação, Ciência e Tecnologia da Paraíba (IFPB), Campus Princesa Isabel, sertão paraibano, mostra-se interessante. Dessa maneira, o objetivo desta pesquisa exploratória é analisar a viabilidade econômico-financeira do projeto, utilizando-se de indicadores tais como payback simples, valor presente líquido (VPL) e taxa interna de retorno (TIR), juntamente com a proposta apresentada por fornecedor reconhecido no mercado e o perfil de consumo de energia elétrica da instituição. Após as análises, o payback indicou um tempo de retorno do investimento de 5,04 anos, o VPL de R$ 30.037.547,36 e a TIR de 30,34%, tendo a taxa mínima de atratividade adotada sido de 10%. Os resultados indicaram um projeto economicamente viável e superavitário ao longo de sua vida útil.

El presente trabajo de revisión tiene como objetivo principal proporcionar una visión general sobre los modos de operación y las principales estrategias de control y regulación diseñadas e implementadas para la operación de sistemas térmicos de frio solar, destacando sus principales características, ventajas e inconvenientes. Además, se detallan las condiciones generales de contorno que rigen el funcionamiento de las máquinas de absorción de LiBr-H2O de simple y doble efecto accionadas por agua caliente, profundizando en los efectos o reacciones que se producen en este tipo de equipos con respecto a las variaciones que puedan ocurrir en las condiciones de funcionamiento del sistema.

Como es conocido, la energía solar es un tipo de energía renovable que por su naturaleza se encuentra intrínsecamente influenciada por la variabilidad del recurso según sean las condiciones meteorológicas y geográficas del lugar. Para contrarrestar dicha variabilidad en la generación, se puede recurrir a tecnologías de almacenamiento como baterías. Estas facilitan la integración de esta energía a la red y la alimentación de las cargas en momentos de baja generación fotovoltaica (FV). En este artículo, se realiza un análisis técnico y económico de un sistema FV que cuenta con almacenamiento de energía por medio de baterías. Para ello, se desarrolla un modelo de un sistema fotovoltaico con y sin almacenamiento de energía, como comparación, para un sistema residencial con tarifa residencial plana. A partir del análisis generado, los resultados obtenidos indican que en términos económicos, es más rentable la instalación de sistemas operando únicamente con módulos fotovoltaicos (basado en el tiempo de retorno de inversión descontado). Por otra parte, a nivel energético los sistemas FV con almacenamiento por medio de baterías, permiten un mayor aprovechamiento de la energía fotovoltaica capaz de extraer el sistema, como es evidenciado por medio de las métricas de autoconsumo y autarquía. Así, este artículo, contribuye al análisis de sistemas fotovoltaicos con almacenamiento de energía por medio de baterías, una tecnología relativamente nueva en el país, colaborando con la generación de conocimiento de sistemas que se prevé cambie sustancialmente los sistemas de eléctricos.

Copyright of Revista de Ciências da Administração is the property of Universidade Federal de Santa Catarina, Departamento de Ciencias da Administracao and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This research addresses the numerical simulation of a working fluid, using specialized SolidWorks Flow Simulation Software, analyzing the behavior of a drying air in a flat solar collector with thermal energy storage. In addition, one of the main centers of computational study is the relationship between flow, air temperature at the outlet of the collector and efficiency; This study allows researchers a vision of the principles of the design of these technologies, especially if it focuses on the drying of food. Then, a proposal is made on the requirements to be taken into account for the sizing of collectors based on the requirements of the product to be dried. Among the results obtained, it is established that a correctly designed collector and under a variable air flow, based on the intensity of the irradiation in specific coordinates and location, can reach efficiencies close to 30% with temperatures close to 60 ° C, being ideal for injecting this fluid into a drying chamber, where the food to be dehydrated is available. For the selection of the volume of the material for energy storage, it is recommended to take the melting temperatures as a base, with a constant flow of air, it is normal that within the system, the temperature varies depending on the position, therefore it is recommending the application of materials with different melting temperatures, which are strategically located within the storage tank. [ABSTRACT FROM AUTHOR]

Project management allows the planning the processes, products, and services necessary for the development of heat transfer calculations. This research developed a solar reactor prototype with an operating temperature range of 170 to 240 °C by deploying project life cycles and the irradiance received in Guadalajara (Mexico). Project management uses the processes of initiation, planning, execution, monitoring, and closure. A conceptually designed solar collector captured the radiation, assuming an irradiance of 1000 W/m2. The startup processes were used to estimate the temperature in the reactor chamber by transfer heat calculations (radiation, convection, and conduction). The planning, execution, and monitoring processes were used to develop the prototype, and closing processes were used to validate its operation through temperature and solar irradiance measurements. The solar reactor prototype provided evidence of its ability to reach an average temperature of 188 °C in a steady state and to receive an average irradiance of 1260 W/m2 in autumn. Heat transfer calculations are valid for developing reactors that work with solar energy and are helpful in geographical areas with similar irradiances. [ABSTRACT FROM AUTHOR]