The object of this project was to verify the potential for the hydrogen production via water electrolysis by using the exceeding electrical energy resulting from the cogeneration process in alcohol and sugar plants. The studies were made from July to November/2007 in plants authorized by the Electrical Energy National Agency (Agência Nacional de Energia Elétrica –ANEEL) that use the sugar cane bagasse as fuel for the generation of thermal and electrical energy. The data were taken from each plant. The processing history of sugar cane for the last five years was verified and the calculations were made based on the values of the 2006/2007 harvest. The operation time of the plants was considered to be 202 days in average. The amount of sugar cane processed daily and the total of bagasse produced, electrical energy generated in a year and exceeding electrical energy were calculated for each plant. Along with the cost of the electrolysers, it was also obtained the cost of the electrolysis plant and the costs of the hydrogen production considering the capacity of production of the plants. The custs of hydrogen using excedent energy are betwen US$ 0,50 Nm3 and US$ 0,75 Nm3.The results show an increasing potential for the generation of exceeding electrical energy that can be used for electrolytic hydrogen production, since the costs for the hydrogen production presented themselves to be similar to the ones found in other studies carried out, however, using other energy sources.
Key words: sugar cane; cogeneration; exceeding electrical energy;