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Over the last decades, wind energy has been named as a clean method to generate electrical power. But, to claim this argument many aspects must be evaluated. On one hand, wind power, as an electrical energy source, generates minimum environmental impact when in operation. On the other side, the material extraction for the manufacturing process does create environmental impact and require electrical energy usage. Therefore, when claiming the sustainability of wind power, as a method of electrical power generation, many aspects must be evaluated, such as the Life Cycle Analysis of the turbine. This study has been taken to evaluate the energy cost and its payback period off the wind power turbine S-600, manufactured by Greatwatt, has being evaluated. This evaluation has covered the embodied energy in the gross material present on the final product and its energetic payback period, for the specific case of working in a rural area in the state of Paraná, Brazil. The ISO 14040 methodology, for life cycle analyses, has being applied to estimate the embodied energy in the gross material present on the generator. The annual average energetic production estimation has considered 4 cases, varying the voltage output and hub height, and the nominal capacity, claimed by the manufacturing company. To assess the embodied energy payback period, the theoretical generation capacity has been estimated. Thus, by this analysis, this article has concluded that the embodied energy in the gross material is 803.39MJ. The energetic payback period for this product, at 10 meters hub height, is 11.6 months, if operating on 12 V, and 12.6 months, if operation on 24 V. Furthermore, in the situation of installed at 30 meters from the ground, the energy payback period drops down to 5.3 and 5.5 months, operating on 12 or 24 V respectively. In the situation of nominal generation, the energetic payback period would dropdown to 4.6 and 3.1 months, operating on 12 or 24 V respectively.

R ESU M O O estudo de fontes alternativas de energia ao oleo diesel mineral, como o biodiesel, com origem renovavel, e importante para o meio-ambiente e diversificacao da matriz energetica. Neste estudo foram levantados o consumo especifico de combustivel, o valor calorico do combustivel e a eficiencia do conjunto motor gerador da marca BRANCO em funcao de cargas resistivas, sob as seguintes proporcoes volumetricas entre o oleo diesel mineral com biodiesel: 0% (B0), 20% (B20), 40% (B40), 60% (B60) e 100% de biodiesel (B100). Para o ensaio utilizou-se motor de 7,36 kW, com gerador eletrico acoplado de 5,5 kW. As cargas utilizadas, 0,5 kW; 1,0 kW; 1,5 kW e 2,0 kW foram elevadas ate 5,0 kW, oriundas de um dinamometro de cargas resistentes. Assim, o desempenho do conjunto para cargas abaixo de 1,5 kW mostrou-se menor, pelo maior consumo especifico de combustivel (CEC), e reducao na eficiencia do conjunto motor gerador para a faixa de potencia. Para as proporcoes de biodiesel B40, B60 e B100 os resultados descreveram reducao no valor calorico e aumento do CEC. Portanto, realizando comparacao das proporcoes de biodiesel com o oleo diesel, a proporcao B20 substitui parcialmente o oleo diesel, sem perdas significativas do desempenho do motor gerador. Palavras-chave: consumo especifico de combustivel, valor calorico, eficiencia do conjunto motor gerador Engine-generator diesel cycle under five proportions of biodiesel and diesel A B ST R A C T The study of mineral diesel alternatives, such as biodiesel, a renewable fuel, is important for the environment and to diversify energy sources. This study evaluated an engine-generator BRANCO brand. Specific fuel consumption, calorific value and the overall efficiency as a function of the system load was measured, using diesel oil and biodiesel blends. The biodiesel proportions in the composition were 0% (B0), 20% (B20), 40% (B40), 60% (B60), and 100% (B100). The engine that was used during the test has a power of 7.36 kW, and the electric generator was 5.5 kW. The group was submitted to resistive loading, in the range: 0.5 kW, 1.0 kW, 1.5 kW; growing up to 5.0 kW. The results have shown that, when operating at lower loads (less than 1.5 kW), the engine-generator performance decreased, while the specific consumption increased, leading to an efficiency reduction. The biodiesel proportions B40, B60 and B100 described reduction in caloric value and increased the specific fuel consumption. Therefore, comparing the proportions of biodiesel with diesel oil, the proportion B20 replaced diesel oil without significant losses in engine-generator performance.

Among the alternatives to meet the increasing of world demand for energy, the use of biomass as energy source is one of the most promising as it contributes to reducing emissions of carbon dioxide in the atmosphere. Gasification is a technological process of biomass energy production of a gaseous biofuel. The fuel gas has a low calorific value that can be used in Diesel engine in dual mode for power generation in isolated communities. This study aimed to evaluate the reduction in the consumption of oil Diesel an engine generator, using gas from gasification of wood. The engine generator brand used was a BRANCO, with direct injection power of 7.36 kW (10 HP) coupled to an electric generator 5.5 kW. Diesel oil mixed with intake air was injected, as the oil was injected via an injector of the engine (dual mode). The fuel gas was produced in a downdraft gasifier. The engine generator was put on load system from 0.5 kW to 3.5 kW through a set of electrical resistances. Diesel oil consumption was measured with a precision scale. It was concluded that the engine converted to dual mode when using the gas for the gasification of wood decreased Diesel consumption by up to 57%. Dentre as alternativas à crescente demanda energética mundial, o uso da biomassa como fonte de energia é uma das formas mais promissoras, pois contribui para a redução das emissões de dióxido de carbono na atmosfera. A gaseificação é uma tecnologia de transformação energética da biomassa num biocombustível gasoso. O gás de gaseificação é um combustível de baixo poder calorífico que pode ser utilizado em motor ciclo Diesel no modo dual para geração de energia elétrica em comunidades isoladas. Este trabalho teve por objetivo avaliar a redução no consumo de Diesel num motor gerador, com a utilização de gás da gaseificação da madeira. O motor avaliado foi da marca BRANCO, com injeção direta e potência de 7,36 kW (10 cv) acoplado a um gerador elétrico de 5,5 kW. O gás de gaseificação foi produzido num gaseificadortipo concorrente, sendo injetado no motor misturado com o ar de admissão e o Diesel injetado pelo injetor do motor (modo dual). O motor gerador foi submetido a cargas que variaram entre 0,5 kW e 3,5 kW, com o auxílio de um banco de resistências elétricas. O consumo de Diesel foi medido por meio de uma balança de precisão. Concluiu-se que o motor convertido para o modo dual, ao utilizar o gás de gaseificação de madeira, apresentou uma redução no consumo de Diesel de até 57%.