Thermodynamic analysis of a solid oxide fuel cell system fuelled by ethanol

In the present study, a detailed thermodynamic analysis has been carried out in order to provide useful information concerning ethanol utilization as alternative fuel in solid oxide fuel cells (SOFCs) by using different oxidants for preliminary fuel reforming. The SOFC was considered being fed with the thermodynamic equilibrium products of ethanol, (a) steam reforming, (b) reforming with CO2 and (c) partial oxidation with air. Equilibrium calculations were performed in the region where carbon formation is thermodynamically impossible, in the temperature range between 800 and 1200 K assuming different oxidant/ethanol ratios of the initial system. It was found that the maximum SOFC system efficiency at T<950 and >1100 K is achieved when the SOFC electrochemical section is fed by the products of ethanol steam reforming, whereas at the intermediate temperature region it seems more preferable to feed the SOFC electrochemical section with the products of ethanol reforming with carbon dioxide. Maximum obtainable SOFC system efficiency if the products of ethanol partial oxidation feed the SOFC electrochemical section is about 20% less compared to the maximum SOFC system efficiency in the previous cases.