Already one of the leaders in the United States’ clean energy economy drive, California launched on Wednesday another program, this time to kick start the purchase of medium- and heavy-duty hybrid vehicles in the state.

The Hybrid Truck and Bus Voucher Incentive Program (H.V.I.P.) is designed to help the state’s truck and bus buyers to choose low-emission vehicles by giving vouchers which directly reduce the vehicles’ costs. The program initially has $20 million to spend.

Vouchers can range from $10,000 to $45,000 per eligible vehicle on a first-come, first-served basis. Through these vouchers, buyers should be able to acquire the hybrid vehicles faster and for half the cost.

The California Air Resources Board expects 800 hybrid vehicles to hit the road because of the incentive, potentially reducing petroleum use and greenhouse gas emissions by 20 percent to 50 percent.

The incentive program will be managed by Calstart, and will limit wholesale buyers to 100 vouchers each to prevent hoarding.

“H.V.I.P. is an exciting project that could lead to the introduction of as many as 800 hybrid trucks and buses on California’s roads, a nearly 50 percent increase in volume for these vehicles in the early market,” said John Boesel, Calstart chief executive.

California wants to reduce its greenhouse emissions to 1990 levels by 2020. The transportation sector is responsible for 40 percent of total emissions in the state.