Hydrogen

Hydrogen mixed with natural gas can be used to power internal combustion engine vehicles. Hydrogen use in internal combustion engines (ICEs) offers several advantages over gasoline: near-zero net emissions (hydrogen-fueled vehicles emit only water vapor), maintaining the utility and flexibility of today’s automobile, and helping to promote a hydrogen fueling infrastructure. Hydrogen ICEs are capable of running on either liquid hydrogen or gasoline. With dual fuel capacity, hydrogen ICEs can be switched to gasoline operation should it become necessary, eliminating any restrictions that might be imposed by range or hydrogen availability. These vehicles also use today’s fuel cell technology to power the vehicle’s electrical system. This source provides more power than a conventional battery, allowing, for example, the air conditioning or heating system to be operated with the engine off.

Pure hydrogen also can be used to power fuel cells, which are under development to power vehicles of the future. In these vehicles, hydrogen and oxygen from air fed into a proton exchange membrane (PEM) fuel cell "stack" produce enough electricity to power an electric automobile. Water is the only emission from these vehicles. Though hydrogen vehicles are not yet available to the general public, demonstration vehicles do exist.

Visual source: http://www.hydrogencommerce.com

Hydrogen Fuel Cells: Fuel cells use hydrogen to produce continuous electric currents. They employ a process that chemically combines hydrogen and oxygen to produce electricity and water. To generate enough energy to meet driving needs, fuel cells must be “stacked” in a row. Electricity is produced when hydrogen is fed into one end of the fuel cell. There it meets a platinum anode that takes one electron from each hydrogen atom, producing an electric current and a stream of hydrogen ions. The electric current flows to the electric motor, supplying it with power. At the other end of the fuel cell, a platinum cathode brings together the stream of hydrogen ions coming from the platinum anode, the electric current returning from the electric motor, and oxygen. These three react to produce water. Fuel cells also can be used to provide electricity and heat to buildings in addition to powering vehicles.

Sources:

• Department of Energy’s Alternative Fuel Data Center
• Auto Alliance