Electricity Diesel, Otto

Fuel cells have the potential to be considerably quieter than Otto or diesel cycle power plants. This would especially reduce the noise in the quiet neighborhoods or highways. At speeds higher than 50 km/h, however, there is still the problem of road noise. Fuel cells produce electricity. This is not the desired form of energy for transportation. The electricity must be converted into mechanical power using an electric motor. The Otto or diesel cycle produces the required mechanical power directly. This gives them an advantage compared to fuel cell-powered automobiles. 

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