Abstract

Due to the rising price of petroleum, researches looking for alternative fuels are intensifying more and more. Brazil has a great availability of biogas from anaerobic digestion of waste in rural areas, of urban waste in landfills and of sewage treatment systems on urban centers. In this paper, an Otto cycle engine was evaluated on a dynamometer, fed with biogas, generating the characteristic curves of the engine for torque and power. First were made control tests, using the systems commercially available for these fuels, so they could serve as a comparative for the other tests. Next were made tests for the several combinations of ignition point, gas mixer and compression rate. By the analysis of the results, it can be concluded that the best power result for biogas was obtained when used compression rate 12.5:1, long gas mixer and spark advance 45°, because in these conditions, it was obtained the maximum power, superior to original biogas.

Key words: Energy, biomass, stationary engine, generator.