ZEV mandate

A zero-emissions vehicle, or ZEV, is a vehicle that emits no exhaust gas 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; electric bicycles; gravity racers; battery electric vehicles, which may shift emissions to the location where the electricity is generated (if the electricity comes from coal or natural gas power plants--as opposed to hydro-electric or nuclear power plants); and fuel cell vehicles powered by hydrogen. Emissions from the manufacturing process are thus not included in this definition, and it has been argued that the emissions that are created during manufacture are of an order of magnitude that is comparable to the one of the emissions that are created during a vehicle's operating lifetime. However, these vehicles are in the early stages of their development; the manufacturing emissions may decrease by the development of technology, industry, and shifting toward mass production.

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