Drivers will now be able to get up to $2,500 in state incentives to help purchase alternative-fuel vehicles, the Texas Commission on Environmental Quality announced this week.

Officials with the commission said it is the first time the agency has offered an alternative fuel vehicle incentive program specifically geared toward light-duty, or consumer, vehicles. The incentive program is part of legislation approved by the state Legislature a year ago.

Joe Walton, manager of the implementation grants section at the commission, said previous efforts to launch the program had sputtered as they have failed to get funding.

The current program will provide up to $7.7 million in incentives to help defray the cost of leasing or buying light-duty vehicles powered by electricity, compressed natural gas or liquefied petroleum gas, also known as propane.

Until now, the agency's incentives have applied to heavy- and medium-duty vehicles that were geared toward fleet applications. But now, buyers of consumer-grade vehicles like the electric Nissan Leaf or Chevy Volt, or CNG versions of the Honda Civic or Ford F-150, are eligible.

The changes are part of the state's Texas Emissions Reduction Plan, which offers financial incentives for lower-emissions vehicles as part of an effort to improve air quality in the state.

The Texas Commission on Environmental Quality had been sorting out the rules of what type of vehicles would be eligible for the program since last year.

The program runs through June 2015 but will conclude if it runs out of money earlier.

Information on the incentives is available at www.terpgrants.org or 800-919-TERP.

The state program would only partially offset the cost of alternative-fuel vehicles, which generally cost significantly more than their gasoline-powered counterparts. Converting an F-150 to run on CNG, for example, can cost $7,500 to $9,500, and the electric Chevrolet Volt costs about $34,000.

But Walton emphasized that the commission's incentives can be combined with other grant programs offered by the state as well as the federal government. The federal government offers tax credits of $2,500 to $7,500 for some electric vehicles, for example.

Meanwhile, with a queue of "clean energy" 18-wheelers ready for fuel, San Antonio on Wednesday lost its distinction of being both a desert for vehicles that run on compressed natural gas and the missing vertex for a "clean transportation triangle" linking its highways with Dallas and Houston.

"With this movement today, the Texas Triangle is officially open for business," Chip Haass, a consultant for the industry group America's Natural Gas Alliance, told public officials, trucking company owners and green-energy advocates gathered at a Flying J truck stop's new natural gas refueling station.

According to the U.S. Department of Energy, Texas has 44 public CNG stations, including the new San Antonio facility.

San Antonio Express-News reporter Lynn Brezosky contributed.