LNG vehicles use liquefied natural gas as a fuel source. Natural gas is compressed to minus 260 degrees Fahrenheit and stored in insulated tanks until it is used by a vehicle's engine. Liquefied natural gas reduces its volume by 600 times from its gaseous state.
Most vehicles that use LNG are designed for heavy-duty use such as shipping. LNG is pure methane, and when these vehicles idle, the tanks release some gaseous methane into the atmosphere because the substance warms up, even with insulated tanks.
As of 2013, one company planned to convert natural gas to unleaded gasoline that costs $2 per gallon for consumers. Natural gas produces electricity for 23 percent of American homes and heats millions of houses as of 2014.