On 2001, Brazil went through an unprecedentedly crisis of energy supply it coincided with restructuration of brazilian electrical sector, that allowed energy own-producers, such as sugar-alcohol sector to commercialize the excess obtained from cogeneration process, that on spite of high potential commercialization it is not being appropriately used. This work characterized cogenerated energy market and analyze the problems in cogenerated energy commercialization, considering transactional and economical costs by sugar-alcohol sector and distributing energy industries. For information collection semi-structured interviews were carried out involving the responsible by the cogeneration area of mills and the distributing energy industries. These interviews consisted of predermined questions that were aplicated in the manner and sequence for all those interviewed to assure comparison of results. The interviews were recorded, transcripted and analyzed through the content analysis. The results indicated that long-term business contract could be stablished, but transactional and economical costs between dealers can overcome the benefits of cogenerated electrical energy commercialization leading the dealers to act preferentialley on spot market.