ABSTRACT
Polymer electrolyte membrane (PEM) fuel cells could potentially become promising power sources for vehicles and stationery combined heat and power (CHP) generators in the near future, as they have higher efficiency and cleaner emission characteristics than conventional engines. Although hydrogen fuel for the cells is mainly produced from natural gas with a conversion efficiency of around 75% at present, well-to-wheel efficiency is still superior to conventional engines. When hydrogen is produced from renewable energy sources, such as solar cells and windmills, PEM fuel cells will be the most powerful devices to convert hydrogen into power with the highest efficiency.
