Internal Combustion Engine Engine – 20% efficient Only 20% of gasoline energy is converted to motion.
Fuel Cells and the Hydrogen Economy Fuels Cells use hydrogen to produce electrical energy. They do not burn hydrogen. 2H 2 +O 2 2H 2 O + energy Fuel cells could be used to power cars with hydrogen as the fuel. Clean fuel
Barriers to Hydrogen Cars Still in development Expensive On-vehicle storage of hydrogen fuel Availability of hydrogen fuel Infrastructure
Vehicle Carbon Emission (grams per mile) Fuel Cell with electricity from coal440 Conventional with gasoline370 Conventional with natural gas310 Hybrid with gasoline190 Hybrid with natural gas170 Fuel Cell with hydrogen from reforming 140