Theoretical Analysis of a PEMFC System fed by an ethanol Steam Reforming Processor

Among the various fuels which can be converted into hydrogen to be used in fuel cells for automotive and stationary applications, alcohols, in particular methanol and ethanol, are very promising candidates because they are easily decomposed in the presence of water and generate a H2-rich mixture suitable for feeding fuel cells. In this paper the energetic optimization of a proton exchange membrane fuel cell fed by a steam reforming system using ethanol as fuel is analyzed. In order to obtain high ethanol reforming conversion efficiency, a thermodynamic analysis of the steam reforming process has been investigated and the optimal operating conditions has been defined. Moreover, the overall efficiency of the PEMFC-SR system has been investigated as a function of operating parameters for stationary applications. The method used to define thermodynamic equilibrium analysis is based on minimising the Gibbs free energy that is normally preferred in fuel-reforming analysis because it is difficult, in reforming process, to calculate equilibrium constants and carbon deposition. The simulations of the steam reforming process has been carried out by using the Aspen PlusTM code.