A Partial Zero Emissions Vehicle (PZEV) is an administrative category within the state of California for low emission vehicles.
This vehicle category was created as part of a bargain with the California Air Resources Board (CARB), so that the automobile manufacturers could postpone producing mandated zero emission vehicles (ZEVs), which will require the production of electric vehicles or hydrogen fuel cell vehicles.
The vehicles constructed to meet the PZEV requirements are called Super Ultra Low Emission Vehicles (SULEVs). Various techniques are used to reduce pollution in these vehicles. In order to qualify as a PZEV, a vehicle must meet the SULEV standard and, in addition, have zero evaporative emissions from its fuel system plus an extended (15-year/150,000-mile) warranty on its emission-control components, which incidentally covers the propulsion electrical components of a hybrid electric vehicle.
Some vehicles can be classified as AT-PZEV, standing for Advanced Technology PZEV. This type of vehicle is just as clean as a PZEV vehicle, but gets much better fuel efficiency due to the use of hybrid electric vehicle systems. This technology can also be used in a Sport Utility Vehicle to improve their traditionally lower fuel economy; however they may still lag behind the efficiency of smaller vehicles.
With the exception of some hybrids and alternative-fuel vehicles, PZEVs do not come with any incentives other than the extended emissions warranty for buyers from either federal or state government. In particular, PZEV vehicles do not automatically qualify for the hybrid vehicle tax credit or for the "clean air vehicle" decal that allows hybrid car drivers to use car-pool lanes.
You can only buy car models that meet PZEV standards if you live in California, Maine, Massachusetts, New York, or Vermont — or in some sales regions near these states. These five "clean car states" have implemented California's more stringent motor vehicle pollution control rules. Other states will soon begin implementing these standards, including Connecticut, New Jersey, Oregon, Pennsylvania, Rhode Island, and Washington. The reasoning is surmised that while modifications only cost $200 for the consumer, it costs as much as $1,500 for the automaker. If the car companies passed on the entire expense, it could hinder sales and slow the automaker's compliance with ultra-low-emission laws