Vehicle Emissions Reduction

Hydrogen

While having the potential to be the cleanest burning motor fuel, hydrogen has many properties that make it difficult to use in motor vehicles. Hydrogen's potential for reducing exhaust emissions stems from the absence of carbon atoms in its molecular structure. Because of the absence of carbon, the only pollutant produced in the course of hydrogen combustion is NOx (of course, the lubricating oil may still contribute small amounts of HC, CO, and particulate matter).

Hydrogen combustion also produces no direct emissions of CO2. Indirect CO2 emissions depend on the nature of the energy source used to produce the hydrogen. In the long-term event of drastic measures to reduce carbon dioxide emissions (to help reduce the effects of global warming), the use of hydrogen fuel produced from renewable energy sources may be the most attractive solution.

Hydrogen can be stored on-board a vehicle as a compressed gas, as a liquid, or in chemical storage in the form of metal hydrides. Hydrogen can also be manufactured on-board the vehicle by reforming natural gas, methanol, or other fuels, or by the reaction of water with sponge iron.