Fuel Cells: fuelling cars to the future

1. NEED FOR FUEL CELLS
After a century of constant improvements, the internal combustion engine still only converts on average about 16 percent of the energy in gasoline to turn the car’s wheels. All heat engines have efficiencies limited by the Carnot Cycle. The theoretical thermodynamic derivation of the Carnot Cycle shows that even under ideal conditions, a heat engine, used to power a vehicle or generator, cannot convert all the heat energy supplied to it into mechanical energy. Some of the heat energy is rejected. In an internal combustion engine, the engine accepts heat from a source at a high temperature (T1), converts part of the energy into mechanical work and rejects the remainder to a heat sink at a low temperature (T2). The greater the temperatures difference between source and sink, the greater the efficiency:
Maximum Efficiency = (T1 – T2) / T1
Where the temperatures T1 and T2 are given in degrees Kelvin
Fuel cell vehicles, not limited by the Carnot Cycle, are e...