IRVINE, CA – The U.S. Postal Service has signed an agreement with General Motors to extend for another year hydrogen fuel cell vehicle testing in the Washington, D.C., area and to expand the program to the West Coast. The announcement was made today at the unveiling of a GM HydroGen3 minivan that will be added to the Postal Service’s Irvine, Calif., mail delivery fleet.

For the past two years, the Postal Service has been collecting and analyzing data from GM’s hydrogen fuel cell minivan, which has been delivering mail three days a week. Though the technology is still being refined, Postal Service engineers say that the minivan has held up well to the rigors of stop-and-go driving and cold weather.

The Postal Service has more than 37,000 alternative-fuel vehicles in its fleet — the largest in the nation. The agency is currently evaluating other kinds of alternative fuels, such as biodiesel; an electric vehicle; and those that run on compressed natural gas and ethanol.