Generator set is a device formed by an internal combustion engine and an alternator responsible for electricity generation all over the world and in many isolated communities in the Amazon region. The use of fossil fuels in generators is very common with a great global dependency on this type of fuel. Facing a world stage with possibility of shortages of oil and water and despite the diversified energy matrix, Brazil has strong dependence of these two energy sources for electricity generation. Researches involving the use of vegetable oil "in natura" to replace, partially or completely, fossil fuels, or be mixed with other types of fuel are growing. In this paper, a modeling and computer simulation of a genset consuming vegetable oil "in natura" enriched with hydrogen and oxygen was carried out in order to improve their energy efficiency as from proposed improvements in the combustion. The modeling and simulations were performed with AVL Boost® software. The computational model was adjusted and validated with the experiment carried out in a Diesel engine of 20 kW, four strokes, indirect injection, naturally aspirated. The study was developed in two phases. At first, the energy substitution of vegetable oil by hydrogen was made in portions of 0% to 20%, in 5% intervals. In the second, oxygen in weight basis was added to the intake air in predefined proportions and the model was simulated until the engine operating limit was reached. It was considered the genset operating with loads of 75%, 80% and 100%, in the simulations. In the two stages of the investigation, the results indicated an increase in electrical power, reduced specific fuel consumption and improved overall efficiency of the generator set. The use of H2 showed increased emissions at full load. In the simulation performed with O2, CO formation decreased and NOx formation increased to partial loads. The simulations indicated that the use of these two energy carriers proved to be very promising, improving the combustion of vegetable oil "in natura" and the energy efficiency of the generator set.
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