Fuel cell technology is of special interest from the present perspective due to its higher efficiency in energy conversion, less harmful emissions and considerable noise reduction. However, in the mid-term pure hydrogen generated from renewable or sustainable energy sources will not be widely available for the operation of a fuel cell. Therefore, the most important precondition for fuel cell systems is the provision of a reliable technology ensuring a steady supply of hydrogen from widely available fuels. In the power range between 500 We – 10 kWe fuels like alcohols or middle distillates are promising candidates for conversion into hydrogen by means of chemical processes.
From 1990 to 2001 Forschungszentrum Jülich gained great experience with steam reforming of methanol. Since 1999 the focus was directed increasingly to the autothermal reforming of diesel. In this study experimental and analytical works on reforming technologies of methanol and diesel were concluded for a case study of an Auxiliary Power Unit based on PEFC and HT-PEFC. The aggregation of results comprises experiments on degradation, start-up times, load changes and power density. The required heat exchanger net work is analysed by a Pinch-Point method. Adiabatic temperatures and chemical reaction equilibrium data were calculated by commercial software. Subsequently, an analysis between thermodynamics and catalytic experiments will be discussed to gain design parameters for the fuel cell system. These results and the need for a preferably simple system define the border line between the usage of methanol or diesel as energy carrier for small APUs.