Glossary of Terms
2D/4D – 2 door/4 door
2WD/4WD – 2 wheel drive/4 wheel drive
A/C – Air Conditioning
AER – All Electric Range is the range of a vehicle using only its electric fuel source or battery pack.
Annual Fuel Costs – This is calculated by dividing your annual miles driven by the vehicle’s typical miles per gallon and multiplying that number by the cost of fuel. The default miles driven per year is 15,000 miles. You can personalize the annual fuel costs displayed in your search results by adjusting the Driving Habits & Fuel Costs default values.
Annual Greenhouse Gas Emissions – This is based upon tailpipe emissions, and emissions from the production and distribution of the fuel type used. When looking at a flex fuel vehicle, the value you see is for the gasoline fuel only. The emissions are calculated by multiplying your annual miles driven by the vehicle’s grams per mile of greenhouse gas emissions. The default miles driven per year is 15,000 miles. You can personalize the annual greenhouse gas emissions displayed in your search results by adjusting the Driving Habits & Fuel Costs default values.
Annual Smog Emissions – This is based upon tailpipe emissions only. They are calculated by multiplying annual miles driven by the vehicle’s grams per mile of NMOG and NOx. When looking at a flex fuel vehicle, the value you see is for the gasoline fuel only. The default miles driven per year is 12,000 miles. You can personalize the annual smog emissions displayed in your search results by adjusting the Driving Habits & Fuel Costs default values.
AT PZEV – Advanced Technology Partial Zero Emission Vehicle is a vehicle emissions rating within California’s exhaust emission standards. An AT PZEV meets the same requirements as a PZEV (meets Super Ultra Low Emission Vehicle exhaust emission stardard, has zero evaporative emissions, and includes a 15 year / 150,000 mile warranty on the emissions system) and includes zero emission vehicle enabling technologies such as hybrids and hydrogen internal combustion engine vehicles. AT PZEVs have a Smog Rating of 9.
AWD – All wheel drive
BIN – Names for Federal emission standards.
Biodiesel – A diesel replacement fuel made from new and used vegetable oils or animal fats that have been chemically reacted with an alcohol.
Carbon Footprint - The total amount of greenhouse gases produced to support a household, including those caused by direct and indirect emissions.
CaFCP – California Fuel Cell Partnership
CaH2Net – California Hydrogen Highway Network
California Emission Standards – Standards adopted by California that regulate the emissions of vehicles sold in the State. California is the only state vested with the authority to develop its own emission regulations, which are often more stringent than the federal rules. Other states have a choice to either implement the federal emission standards, or else to adopt California requirements.
CEV – City Electric Vehicles have 50-75 miles range and are smaller versions of battery EVs intended for around town use.
City Fuel Economy – Estimated miles-per-gallon in the city. City Fuel Economy represents urban driving, in which a vehicle is started after not running for 12 hours and driven in stop and go traffic.
CH4 – Methane
Class – A category based upon vehicle weight that is used in determining a vehicle’s emissions certification.
CMPEG – California Miles Per Equivalent Gallon (gasoline)
CNG – Compressed Natural Gas is a compressed mixture of hydrocarbons consisting mainly of methane.
CO2 – Carbon Dioxide is a colorless, odorless, poisonous gas that contributes to global warming.
CO2 Equivalent Value – the sum of a vehicles greenhouse gas emissions used to determine a vehicle’s Greenhouse Gas Rating. Greenhouse gases (ghg) emitted from vehicles include Carbon Dioxide (CO2), Methane (CH4), Nitrous Oxide (NO2), and Hydroflurocarbons (HFCs) from air conditioner refrigerant.
Combined Fuel Economy – the fuel economy from driving a combination of 55% city and 45% highway miles and is calculated as 1 / [(0.55/city mpg) + (0.45/highway mpg)]
Default Fuel Prices - These are default values for various fuels (gasoline, E85, CNG, diesel, biodiesel and electricity) used to calculate annual fuel costs. You can personalize the annual fuel costs displayed in your search results by adjusting the Driving Habits & Fuel Costs default values.
Direct vs. Indirect Emissions - Emissions from sources that burn fuels directly, such as a car or natural gas fired water heater are direct emissions. Indirect emissions are a consequence of actions at a home, but result in emissions elsewhere, such as at a power plant that produces the electricity you use in your home.
DOE – Department of Energy
Emission Certification Standard – EPA and California-required standards. The names refer to tables of numerical limits for the various air pollutants allowed by the standards.
Engine Family Number – A number given to a specific engine used by a manufacturer to certify emissions (also called a “test group number”).
Engine Size – A vehicle’s engine size is measured by displacement, normally given in units of liters (3.2L = 3.2 liters) or number of cylinders. Larger, more powerful engines usually have more cylinders than smaller engines.
Enhanced AT-PZEV is a vehicle that meets the AT-PZEV requirements and makes use of an off-board ZEV fuel such as electricity or hydrogen.
EPA Fuel Economy Estimates – EPA estimates are based upon vehicle-specific data from tests designed to replicate real-world conditions, which can significantly affect fuel economy: high-speed/rapid acceleration driving, use of air conditioning, and cold temperature operation. Other conditions such as road grade, wind, tire pressure, and fuel property differences are also considered. EPA Fuel Economy Estimates can be found www.FuelEconomy.gov.
EP Label – Environmental Performance Label
Ethanol or E85 – Ethanol is an alcohol made primarily from corn and can be used in flexible fuel vehicles, which are capable of operating on gasoline, E85 (85% ethanol, 15% gasoline), or a mixture of both.
Evaporative Emissions – Emissions that escape from the engine when a vehicle is sitting idle.
FCEV or HFCF – 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.
FE – Fuel Efficiency
FFV – flex fuel vehicle
Fuel Efficiency or Fuel Economy – Refers to the average number of miles traveled per gallon of fuel consumed.
G/Mile – Grams per Mile
GHG – Greenhouse Gas
Global Warming – Greenhouse gases trap heat in the atmosphere, thereby creating a greenhouse effect known as global warming. Some greenhouse gases occur naturally and are emitted in the atmosphere through natural processes and some are created through human activities.
Global Warming Score or GW – A score that ranks each vehicle’s CO2-equivalent value on a scale of 1-10 (10 being the cleanest) relative to all other vehicles. All vehicles manufacturered after January 1, 2009 must display this score on the Environmental Performance Label.
The greenhouse gas rating is based on emissions data from ARB’s motor vehicle greenhouse gas emissions regulatio known as AB 1493 or Pavely. The greenhouse gas regulation establishes a CO2-equivalent value that includes all the various global warming gases based on their relative contribution to global warming. The CO2-equivalent value is as follows:
CO2 Equivalent = CO2+296xN2O+23xCH4–A/C Direct Emissions Allowance–A/C Indirect
Using this equation, and accounting for the upstream emissions factor for alternative fuels, ARB accounts for all global warming gasses being released into the atmosphere due to the operation of each vehicle.
Greenhouse Gases – Greenhouse gases emitted from vehicles include Carbon Dioxide (CO2), Methane (CH4), Nitrous Oxide (NO2) and Hydroflurocarbons (HFCs) from air conditioner refrigerant.
H2 – Hydrogen
HC – Hydrocarbon
HFC – Hydroflourocarbons
Hybrid Electric Vehicle or HEV – Hybrids commercially available today combine an internal combustion engine with a battery and electric motor.
Highway Fuel Economy – Estimated miles-per-gallon on the highway. Highway fuel economy represents a mixture of rural and interstate highway driving in a warmed-up vehicle, typical of longer trips in free flowing traffic at higher than city speeds.
Hydrogen Fuel Cell Vehicles - These vehicles use hydrogen and a fuel cell to create electricity.
Hydrogen ICE Vehicles – These vehicles have an internal combustion engine (ICE) that is specially designed to run on hydrogen fuel.
Incentives – tax credits, financial rebates/discounts, or non-monetary conveniences offered to encourage further use of advanced technology vehicles and alternative fuels.
LEV 1 LEV - Low Emission Vehicle rating within California’s LEV 1 exhaust emission standards. The LEV 1 emission standards apply to cars from 1994-2003. However some cars were stil certified as LEV 1 LEV's after 2003.
LEV 2 LEV – A Low Emission Vehicle emissions rating within California’s LEV 2 exhaust emission standards. The LEV 2 emission standards were adopted in 1998 and apply to cars from 2004-2010. However some cars were certified as LEV 2 LEV's before 2004.
LEV 1 ULEV – An Ultra Low Emission Vehicle is a vehicle emissions rating within California’s LEV 1 exhaust emission standards. The LEV 1 emission standards apply to cars from 1994-2003. However some cars were stil certified as LEV 1 LEV's after 2003.
LEV 2 ULEV– An Ultra Low Emission Vehicle emissions rating within California’s LEV 2 exhaust emission standards. The LEV 2 emission standards were adopted in 1998 and apply to cars from 2004-2010. However some cars were certified as LEV 2 LEV's before 2004.
LCFS – Low Carbon Fuel Standard
LDT - Light Duty Truck
LEV 1 or Tier 1 Emission Standards – California emission standards that extend through the year 2003.
LEV 2 Emission Standards – Emission standards adopted by California in 1998 which extend from the year 2004 – 2010.
LiIon – Lithium Ion (battery)
LNG – Liquified Natural Gas
Make – the manufacturing company, or, in some cases, a division of a manufacturing company, such as "Chevrolet", "Acura", or "Jeep".
MPG – Miles per gallon, a measure of fuel economy.
MPG(e) – Miles per gallon equivalent
Model – the name of the vehicle. In some cases, manufacturers subdivide a model according to various trim levels.
Model Year – Model year refers to the actual annual production period (year) as determined by the manufacturer.
MDV – Medium Duty Vehicle
MeOH – Methanol
MSRP – Manufacturer Suggested Retail Price
NEV – A Neighborhood Electric Vehicle is a low speed vehicle.
NiMH – Nickel Metal Hydride (battery)
NMOG – Non-Methane Organic Gas. Compounds containing carbon which, when combined with NOx in the presence of sunlight, form smog.
NOx – Oxides of Nitrogen. NOx is a lung irritant. When combined with hydrocarbons and sunlight, NOx compounds form smog.
OBD – On Board Diagnostics
PbA – Lead Acid (battery)
PC – Passenger Car
PEM – Proton Exchange Membrane (fuel cell).
PEV - Plug-in Electric Vehicle - are vehicles that can be recharged from any external source of electricity and the electricity is stored in a rechargeable battery pack to drive or contribute to drive the wheels. These types of cars include Battery Electric Vehicles and Plug-in Hybrid Electric Vehicles. Visit our Plug-in Vehicle Resource Center
Plug-in Hybrid Vehicle or PHEV – These vehicles are similar to traditional hybrids but are also equipped with a larger, more advanced battery that allows the vehicle to be plugged in and recharged in addition to refueling with gasoline. This larger battery allows the car to drive on battery alone, gasoline alone, or a combination of electric and gasoline fuels. Visit our new Plug-in Vehicle Resource Center
PM – Particulate Matter. Tiny particles of solid matter that lodge in the lungs and form deposits on buildings. PM is likely a cancer-causing carcinogen.
PZEV – Partial Zero Emission Vehicle is a vehicle emissions rating within California’s exhaust emission standards. Cars that are certified as PZEVs meets the Super Ultra Low Emission Vehicle exhaust emission stardard, has zero evaporative emissions from its fuel system and includes a 15 year / 150,000 mile warranty on the emissions system. PZEVs run on gasoline, yet offer extrememly clean emissions and an extended warranty and zero evaporative emissions. PZEVs have a Smog Rating of 9.
Regenerative Breaking – partial recovery of the energy normally dissipated into friction breaking that is returned as electrical current to an energy storage device.
Smog – a haze-like form of air pollution produced by the photochemical reaction of sunlight with volatile organic compounds (including NMOG and NOx) that have been released into the atmosphere, especially by automobile emissions.
Smog Score or SS – Ranks a vehicle’s pollutant levels of Non-Methane Organic Gases (NMOG) and Oxides of Nitrogen (NOx) relative to all other vehicles within the current model year. Smog Ratings are on a scale or 1-10, with 10 being the cleanest. All new vehicles display this score on the Environmental Performance Label.
SULEV – Super Ultra Low Emission Vehicle is a vehicle emissions rating within California’s LEV 1 and LEV 2 exhaust emission standards.
SUV – Sport Utility Vehicle
Typical Miles Per Gallon (MPG) - Each vehicle on DriveClean.ca.gov is associated with a fuel economy estimate that is most typical for that vehicle. These numbers are based upon the EPA's estimated fuel economy, but may not reflect small variations in miles per gallon with every model (for instance, between an automatic and manual transmission). The most typical fuel economy for each vehicle model is chosen, and it is used to calculate annual fuel costs.
Test Group Number – A number given to a specific engine used by a manufacturer to certify emissions (also called an “engine family number”).
TLEV – Emissions rating within California’s LEV 1 exhaust emission standards.
TIER1 – Emissions rating within California’s LEV 1 exhaust emission standards.
Transmission – The gearbox that provides different gear ratios between the engine and the drive wheels including reverse gear.
Upstream Emissions – Emissions from processes up to when the fuel enters a vehicle – typically during extraction, production, distribution, dispensing of the fuel. The upstream emissions of alternative fuels are taken into consideration when the Greenhouse Gas Rating is determined. These factors are:
Upstream Adjustment Factors for Alternative Fuels
Conventional Gasoline (RFG)
Compressed Natural Gas (CNG)
Liquid Propane Gas (LPG)
Upstream CO2-equivalent Values for Hydrogen Internal Combustion Engine, Hydrogen Fuel Cell Electric, and Battery Electric Vehicles
Hydrogen – Fuel Cel
Hydrogen – Internal Combustion Engine (ICE)
VECI Label – Vehicle Emissions Control Information Label. This is found under the hood of every vehicle and displays emissions information, including the engine family number.
VMT – Vehicle Miles Traveled
ZEM – Zero Emission Motorcycle
ZEB or ZBUS – Zero Emission Bus
ZEV – means a vehicle that produces no emissions from the on-board source of power. The only technologies that meet this definition are Battery Electric Vehicles and Hydrogen Fuel Cell Vehicles. Visit our Plug-in Vehicle Resource Center
ZEV Program – Zero Emission Vehicle Program
Zero Emission VMT – the vehicle miles traveled with zero
exhaust emissions of any criteria pollutant.