IRS Definitions of "Alternative Vehicles"

an fyi:

"Alternative Motor Vehicle

An alternative motor vehicle is a vehicle with at least four wheels that qualifies as one of the following types of vehicles.
Advanced lean burn technology vehicle. This is a new vehicle with an internal combustion engine that incorporates direct injection, is designed to operate primarily using more air than is necessary for complete combustion of the fuel, and that meets certain additional requirements.

Qualified hybrid vehicle. This is a new vehicle that draws propulsion energy from onboard sources of stored energy that are both an internal combustion or heat engine using consumable fuel and a rechargeable energy storage system, and that meets certain additional requirements.

Qualified alternative fuel vehicle. This is a new or converted vehicle fueled solely by compressed natural gas, liquefied natural gas, liquefied petroleum gas, hydrogen, any liquid that is at least 85 percent methanol, or a mixture of one of these fuels and a petroleum-based fuel, and that meets certain additional requirements.

Qualified fuel cell vehicle. This is a new vehicle propelled by power derived from one or more cells that convert chemical energy directly into electricity by combining oxygen with hydrogen fuel, and that meets certain additional requirements.

Qualified plug-in electric drive motor vehicle. This is a vehicle converted to be propelled to a significant extent by an electric motor that draws electricity from certain batteries capable of being recharged from an external source of electricity, and that meets certain additional requirements.

Certification and other requirements. Generally, you can rely on the manufacturer's (or, in the case of a foreign manufacturer, its domestic distributor's) certification that a specific make, model, and model year vehicle qualifies for the credit and the amount of the credit for which it qualifies. "