Facts about electric vehicle conversions by individuals

This page last reviewed December 20, 2013

Today's high fuel prices and concerns about air pollution, climate change, and our nation's dependence on foreign oil have led many California motorists to look for alternatives to gasoline-powered vehicles. Because of innovative emission standards, California consumers now have a broad range of new alternative-fueled vehicle choices. In addition to production vehicles, California permits the conversion of existing vehicles to full electric drivetrains as long as the conversion does not increase smog-forming emissions or create other pollution problems. The following guidelines apply to individuals converting vehicles equipped with internal combustion engines to full electric power for their own use.

What is an “Electric Vehicle Conversion?"

This is a vehicle conversion where the internal combustion engine and all related fuel components have been permanently removed from an existing vehicle and replaced by an electric motor and storage batteries. Vehicles converted to use a combination of an internal combustion engine and electric power, known as "hybrid" vehicles, can create substantial emissions and are not covered under this conversion policy.

Which vehicles may be converted?

Any vehicle that can be legally registered in the United States or California may be converted following these guidelines. Look for the US Department of Transportation or “DOT” label to verify compliance with US highway safety requirements.

What is required to be installed in the conversion?

A conversion to a full electric drivetrain includes an electric motor and battery capacity sufficient to power the type of vehicle being converted and allow safe operation on public streets and highways. The Smog Check Referee inspector may refuse to evaluate vehicles deemed unsafe, poorly constructed, or underpowered for safe use on public streets.

What is required to be removed in the conversion

To ensure the validity of electric vehicle conversions, all components related to the internal combustion engine, exhaust, and fuel system must be permanently removed from the vehicle. This includes, but is not limited to:

  • Entire engine
  • Cooling system (unless required for functioning liquid cooled electric motors, batteries, electronics, or charge system)
  • Fuel tank, filler neck, pumps, all hard and soft fuel lines, and fuel evaporative system
  • Any non-functioning transmission or drive shaft elements
  • Complete exhaust system, including hangers

Must a conversion use specific parts?

Vehicle owners may use any combination of electric motors, controllers, and batteries or purchase a kit of components for their project. Like other homebuilt or "Special Construction" vehicles allowed under California law, it is the owner's responsibility to ensure that their conversion is safe and reliable. Keep in mind however that DMV staff, the smog check referee, or CHP personnel may bar the registration or use of vehicles deemed unsafe for public roads.

Must I insure my conversion?

Electric vehicles, like any other vehicle used on California roadways, is subject to minimum insurance requirements. Please contact your insurance agent for more information.

Inspection of the converted vehicle is required

An inspection of the converted vehicle is required by a State of California Smog Check Referee station. After inspecting the vehicle and determining it is powered only by battery stored electricity, the referee will sign a “Statement of Facts” indicating the vehicle has been successfully converted. The referee will also affix a new emission control information label to the vehicle. The Statement of Facts is then presented to the DMV to request a change of the vehicle's registered “Motive Power” to indicate the vehicle is powered by electricity. The vehicles VIN number and California license plate number will remain the same.

Will the vehicle require future inspections

Electric vehicles are not subject to the Smog Check program, however the the DMV may request future inspections to verify that the vehicle remains fully electric powered.

Do converted vehicles qualify for the California solo-access carpool lane stickers?

Single occupant carpool or "HOV"" lane access stickers are reserved for manufacturer certified advanced technology alternative fuel and zero-emission vehicles only. Individual vehicle conversions do not qualify for this incentive. Certification by the vehicle original manufacturer verifies that significant performance, efficiency, and durability goals for production vehicles are met. It is not practical for individual conversions to demonstrate compliance with these advanced technology standards required of new vehicle manufacturers.

For More Information

For more information regarding the conversion of existing vehicles to an electric drive, please contact ARB's HELPLINE