The U.S. Postal Service has awarded a contract to the Ford Motor Co. for the purchase of 500 electric delivery vehicles, with the option of ordering up to 6,000 vehicles. It is the single largest purchase of electric vehicles in U.S. history. Production of the 500 vehicles will begin this fall and continue over a period of one year at the rate of 45 a month. California will receive 480 of the vehicles. The balance will go to Maryland, Virginia, and Washington, D.C. Assembled in Rome, N.Y., the battery-powered vehicles can be driven between 50 and 80 pollution-free miles before recharging and accelerate from zero to 50 mph in 12.5 seconds. The Postal Service partnered with the states of California and New York, the California Energy Commission, the Dept. of Energy, and several other organizations on the project. Because of the partnerships, the fleet of vehicles will cost no more than their gasoline-powered counterparts.