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"-A ventura vai guiando as nossas coisas melhor do que pudéramos desejar; pois vê lá, amigo Sancho Pança, aqueles trinta ou pouco mais desaforados gigantes, com os quais penso travar batalha e tirar de todos a vida, com cujos despojos começaremos a enriquecer, pois esta é boa guerra, e é grande serviço de Deus varrer tão má semente da face da terra.-Que gigantes? -disse Sancho Pança.-Aqueles que ali vês -respondeu seu amo -, de longos braços, que alguns chegam a tê-los de quase duas léguas.-Veja vossa mercê -respondeu Sancho -que aqueles que ali aparecem não são gigantes, e sim moinhos de vento, e o que neles parecem braços são as asas, que, empurradas pelo vento, fazem rodar a pedra do moinho.-Logo se vê -respondeu D. Quixote -que não és versado em coisas de aventuras: são gigantes, sim; e se tens medo aparta-te daqui, e põe-te a rezar no espaço em que vou com eles me bater em fera e desigual batalha." A comercialização de energia elétrica no Brasil e no mundo sofreu diversas modificações nos últimos 20 anos. Com o objetivo de alcançar o equilíbrio econômico entre oferta e demanda do bem chamado eletricidade, os agentes deste mercado seguem as regras definidas pela sociedade (governo, empresas e consumidores) e também as leis da natureza (hidrologia). Para tratar de problemas tão complexos, estudos são realizados na área da heurística computacional.O objetivo deste trabalho é elaborar um software de previsão de preços do mercado spot utilizando redes neurais artificiais (RNA). As RNA são muito utilizadas em diversas aplicações, principalmente em heurística computacional, nas quais sistemas não lineares apresentam desafios computacionais difíceis de serem superados devido ao efeito da "maldição da dimensionalidade". Tal maldição se deve pelo fato do poder computacional atual não ser suficiente para processar problemas com elevada combinação de variáveis. O problema de prever os preços do mercado spot depende de fatores como: (a) a previsão de demanda (carga); (b) a previsão da oferta (reservatórios, regime de chuvas e clima), fator de capacidade; e (c) o equilíbrio da economia (precificação, leilões, influência de mercados externos, política econômica, orçamento governamental, política governamental).Estes fatores são utilizados na construção do sistema de previsão e os resultados de sua eficácia são testados e apresentados. The commercialization of electricity in Brazil as well as in the world has undergone several changes over the past 20 years. In order to achieve an economic balance between supply and demand of the good called electricity, stakeholders in this market follow both rules set by society (government, companies and consumers) and set by the laws of nature (hydrology). To deal with such complex issues, various studies have been conducted in the area of computational heuristics.This work aims to develop a software to forecast spot market prices in using artificial neural networks (ANN). ANNs are widely used in various applications especially in computational heuristics, where non-linear systems have...

Small wind turbines (SWTs) represent an opportunity to promote energy generation technologies from low-carbon renewable sources in cities. Tall buildings are inherently suitable for placing SWTs in urban environments. Thus, the Institute of Energy and Environment of the University of São Paulo (IEE-USP) has installed an SWT in an existing high-height High Voltage Laboratory building on its campus in São Paulo, Brazil. The dataset file contains data regarding the actual electrical and mechanical operational quantities and control parameters obtained and recorded by the internal inverter of a Skystream 3.7 SWT, with 1.8 kW rated power, from 2017 to 2022. The main electrical parameters are the generated energy, voltages, currents, and power frequency in the connection grid point. Rotation, referential wind speed, and temperatures measured in some points at the inverter and in the nacelle are also recorded. Several other parameters concerning the SWT inverter operation, including alarms and status codes, are also presented. This dataset can be helpful for reanalysis, to access information, such as capacity factor, and can also be used as overall input data of actual SWT operation quantities.

Over the last few decades, and more prominently currently, many countries have launched and reinforced campaigns to reduce CO2 emissions from all human activities and, in the area of energy, promote energy generating technologies from low carbon, renewable sources, especially wind and solar. In recent years, this promotion of renewables can be seen in statistics as well as an extraordinary increase in plants using renewable sources. There is more activity surrounding the use of small devices installed close to consumers, such as small wind turbines (SWT). In cities, the best places to install SWT are tall buildings. The Institute of Energy and Environment (IEE-USP) has installed a 1.8 kW SWT on the University of São Paulo campus in São Paulo, Brazil. Even with low-magnitude winds at the site, the SWT installation was carried out to serve as a didactic apparatus and demonstration initiative of wind energy generation connected directly to the University’s electric grid, which already has other embedded renewable sources installed, namely photovoltaic and biogas plants. The turbine was placed on the roof of the existing High Voltage Laboratory building, leading to an operating height of 35 m. This paper presents previous local wind data measurements using a Lidar system, annual energy yield estimation calculations, and measurements, also bringing all implementation details. It reports and analyzes the operation and energy production data from three full operational years, from 2018 to 2020, discussing and concluding with further improvements of SWT from technical and economic aspects.