A new low temperature fuel cell based on phosphotungstic acid electrolyte was realized. The electrochemical activity was investigated by polarization curves and lifetime experiments. An output electrical power of 700 mW cm(-2) was obtained at 25 degrees C and 1 atm. Lifetime tests showed that the cell performance remained stable for prolonged periods of operation (more than 300 h). The influence of electrokinetic and mass transport parameters was investigated by digital simulation of the galvanostatic current-potential data. Cell performance is mainly determined by the high conductivity characteristics of the electrolyte and its promoting effect towards the oxygen reduction reaction.