Mono-fuel vehicle means a vehicle that is designed to run primarily on one type of fuel;
Bi-fuel vehicle means a vehicle with two separate fuel storage systems that can run part-time on two different fuels and is designed to run on only one fuel at a time;
Flex fuel vehicle means a vehicle with one fuel storage system that can run on different mixtures of two or more fuels.
Geothermal energy means energy contained in heat that continuously flows outward from the earth that is used as the sole source of energy to produce electricity.
Pure electric vehicle (PEV) means a vehicle equipped with a powertrain containing exclusively electric machines as propulsion energy converters and exclusively rechargeable electric energy storage systems as propulsion energy storage systems.
Hybrid electric vehicle (HEV) means a hybrid vehicle where one of the propulsion energy converters is an electric machine.
Commercial vehicle means a motor vehicle, trailer, or semitrailer used or