The project concerns the development of a silent power solution with a low IR-signature for the energy supply of military land vehicles. An inline desulphurisation unit based on the industrial hydrodesulphurisation (HDS) process will be developed. The resulting fuel will then be fed into an autothermal reformer (ATR). Afterwards it is converted into hydrogen-rich fuel by a two-stage water-gas-shift reaction (WGS). The gas obtained is now transferred to the anode of the HT-PEM fuel cell. Long-term tests and start-stop cycles with hydrogen with impurities (carbon monoxide and hydrogen sulphide) are carried out. The influence of impurities is investigated by regularly recording a polarization curve and additional electrochemical impedance spectroscopy. Within these tests, limits for the tolerance of the cell against the investigated impurities shall be determined so that requirements for the fuel processor can be given.