A
zero-emissions vehicle, or
ZEV, is a vehicle that emits no
tailpipe pollutants from the onboard source of power. Harmful pollutants to the health and the environment include
particulates (
soot),
hydrocarbons,
carbon monoxide,
ozone,
lead, and various
oxides of nitrogen. Although not considered emission pollutants by the original
California Air Resources Board (CARB) or
U.S. Environmental Protection Agency (EPA) definitions, the most recent common use of the term also includes
volatile organic compounds, several air toxics (most notably
1,3-Butadiene), and global pollutants such as
carbon dioxide and other
greenhouse gases. Examples of zero emission vehicles include
muscle-powered vehicles such as
bicycles;
gravity racers;
battery electric vehicles, which typically shift emissions to the location where the electricity is generated e.g. coal or natural gas power plant; and
fuel cell vehicles powered by hydrogen, which typically shift emissions to the location where the hydrogen is generated. Hydrogen-powered vehicles are not strictly zero-emissions, as they do emit
water or
water vapor, although they are still usually included in this category. Emissions from the manufacturing process are ignored in this definition, although more emissions are created during manufacture than during a vehicle's operating lifetime.