Advanced Clean Cars introduction

Advanced Clean Cars Glossary

Air Quality Standard (AQS)

The federal or state prescribed level of a pollutant in the outside air that should not be exceeded during a specific time period to protect public health.

Battery Electric Vehicle (BEV)

A vehicle that runs on electricity stored in batteries and has an electric motor rather than an internal combustion engine.

California Air Resources Board (ARB or CARB)

The state's lead air quality agency governed by a board of 11 governor-appointed members and employing about 1,100 staff. ARB is responsible for attainment and maintenance of the state and federal health-based air quality standards. The Board is fully responsible for controlling emissions from motor vehicles, fuels, consumer products and sources of toxic air contaminants. It is the lead agency on implementing controls on global warming emissions, and it oversees county and regional air pollution control districts.

California's Hydrogen Initiatives

As a ZEV technology, hydrogen fuel cells paly a significant role in reducing California's greenhouse gas and smog emissions. California has many hydrogen initiatives that support hydrogen vehicles and fueling.

Clean Vehicle Rebate Project (CVRP)

An ARB program designed to accelerate widespread commercialization of zero- emission vehicles and plug-in hybrid electric vehicles. Offers consumer rebates up to $2,500 to partially offset the higher cost of these advanced technologies. News Release

Corporate Average Fuel Economy (CAFE)

The sales weighted average fuel economy, expressed in miles per gallon, of a manufacturers fleet of passenger vehicles with a gross weight of 8,500 lbs. or less.

Electric Vehicle (EV)

Unlike a hybrid car, which is fueled by gasoline and uses a battery and motor to improve efficiency, an electric car is powered exclusively by electricity and emits virtually no air pollutants.

Emission Standard

The maximum amount of a pollutant allowed to be emitted from a polluting source such as an automobile.

Flexible Fuel Vehicle (FFV)

Vehicles that can use a combination of fuels such as alcohol fuel and unleaded gasoline.

Fossil Fuels

Fuels formed in the Earth's crust over millions of years from decomposed organic matter. The most widely known fossil fuels are petroleum (oil), coal, and natural gas.

Fuel Cell

A cell that captures the electrical energy of a chemical reaction between fuels such as liquid hydrogen and liquid oxygen to generate electrical current, giving off only water vapor as a by-product.

Fuel Cell Electric Vehicle (FCEV)

A zero-emission vehicle that runs on compressed hydrogen fed into a fuel cell "stack" that produces electricity to power the vehicle.

Global Warming

A term used to describe the phenomenon of Earth's rising average near-surface temperature. Although such fluctuations have occurred in the past due to natural causes, the term is most often used today to refer to current warming trends. Most scientists have concluded that this is very likely due to the observed increase in human-generated greenhouse gas concentrations in the atmosphere.*Source information.

Greenhouse Gases (GHG)

A gas which, like a greenhouse window, allows sunlight to enter and then prevents heat from escaping, in this case, from Earth's atmosphere. The most common greenhouse gases are water vapor, carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O), halocarbons, and ozone (O3).

Hybrid Electric Vehicle (HEV)

A vehicle that combines an internal combustion engine with a battery and electric motor. This combination offers the range and refueling capabilities of a conventional vehicle, while providing improved fuel economy and lower emissions.


Compounds containing various combinations of hydrogen and carbon atoms. They may be emitted into the air by natural sources (e.g., trees) and as a result of fossil and vegetative fuel combustion, fuel volatilization and solvent use. Hydrocarbons are a major contributor to smog.

Hydrogen Fuel Cell Vehicles

Hydrogen fuel cell vehicles are zero emission and run on compressed hydrogen fed into a fuel cell "stack" that produces electricity to power the vehicle. A fuel cell can be used in combination with an electric motor to drive a vehicle.

Internal Combustion Engine

An engine in which both the heat energy and the ensuing mechanical energy are produced inside the engine. Includes gas turbines, spark ignition gas and compression ignition diesel engines.

Low Emission Vehicle (LEV)

A vehicle that meets the ARB's low emission vehicle standards. LEV Program Brochure

Nitrogen Oxides (NOx)

Compounds of nitric oxide (NO) and other oxides of nitrogen created in fuel combustion. These are major smog-forming compounds.

Non-Methane Organic Gas (NMOG)

The sum of non-methane hydrocarbons and other organic gases such as aldehydes, ketones and ethers.


A caustic gas that occurs in sunlight. Up high, in the stratosphere, ozone is beneficial, blocking much of the sun's harmful ultraviolet radiation (like a sunscreen). Down low, in the troposphere, ozone can damage both plant and animal tissues, especially leaf or lung tissue. Ozone is not emitted directly as a pollutant, but forms when pollutants such as hydrocarbons and nitrogen oxides react chemically in sunlight. Ground-level ozone is the main ingredient of smog. In California, motor vehicles are the main source of smog-forming pollution.

Partial Zero Emission Vehicle (PZEV)

Vehicles that meet ARB's Super Ultra-Low Emissions standard of 0.03 grams per mile of non-methane organic gases and nitrogen oxides; have no evaporative emissions; and have a 15 year/150,000 mile warranty.

Particulate Matter (PM)

Extremely small particles of solid or liquid droplets suspended in either a liquid or gas. Particulate matter is a common emission from the combustion of fossil fuels and can increase the risk of health problems. Examples include dust, smoke, aerosols, and other fine particles. LEV Program Brochure

Plug-in Hybrid Electric Vehicle (PHEV)

A plug-in hybrid has all the abilities of a traditional hybrid electric vehicle (HEV) but gives you the option of plugging into grid-provided electricity to recharge the battery pack. By running a car off grid electricity you can significantly increase fuel economy. Plug-in hybrids also have larger, more advanced battery packs than those that power HEVs, allowing you to drive farther solely on electricity.


A combination of smoke and other particulates, ozone, hydrocarbons, nitrogen oxides and other chemically reactive compounds which, under certain conditions of weather and sunlight, may result in a murky brown haze that causes adverse health effects. Ozone is the main ingredient of smog. Motor vehicles are the single largest source of smog-forming compounds in California.


Very fine carbon particles that have a black appearance when emitted into the air.

Zero Emission Vehicle (ZEV)

Vehicles which produce no emissions from the on-board source of power (for example, a fully electric vehicle). ZEV Program