Eight States pledge for Zero-Emission Vehicles. Governors of eight states announced a groundbreaking initiative to put 3.3 million zero-emission vehicles (ZEV) on the roads by 2025. These eight states representing nearly a quarter of U.S. auto sales signed a pact to boost the number of electric- and hydrogen-fueled cars, trucks and buses. These states have the main mission to help make the highways friendlier for zero-emission vehicles. And California is helping lead the charge.