The Department of Energy has switched on its largest demonstration of electric cars, chosing five contractors who will put at least 165 electric-powered or hybrid-powered vehicles on the road within a year.

Seeking to have 10,000 electric vehicles humming down the highways by 1984, DOE picked the five companies to try the nonpolluting power plants in everyday use.

Four of the companies will add the electric vehicles to their own fleets and the fifth, a New Jersey auto dealer, will sell or lease electric cars to small businesses.

The other companies awarded DOE contracts are Walt Disney World in Florida; Consolidated Edison Co., two New York City area utility companies; and American Telephone . Telephone Co.'s Los Angeles office.

The companies will buy 165 cars, pickups and vans which already have met DOE performance standards for speed, range, energy consumption, battery life, recharge time, safety, etc. Most will be powered by batteries turning electric motors, but some will utilize hybrid power plants in which internal combustion engines provide power directly or through generators.

Within hours of the DOE announcement, a private consumer group, the Center for Auto Safety, accused the department of reducing vehicle safety unnecessarily by setting performance standards too low, United Press International reported.

(Clarence Ditlow of the center said in a letter to acting Assistant Energy Secretary Donald Beattie that the required minimum acceleration standard of zero to 31 MPH in 15 seconds is inadequate and will result in "decreased safety and an unnecessary reduction in consumer satisfaction."

(Beattie had said in new conference, that acceleration would be adequate.)

In addition to the private tests, DOE said government agencies will purchase 35 electric vehicles for testing.

Another 600 electric vehicles will be purchased next year, 1,700 in 1980 and 7,500 more by 1984 for continuing DOE demonstration programs.

Long Island Lighting said its 60 electric vehicles will be tried in a van pooling program for commuting workers and as service cars. AT&T will use its 20 electrics to toddle telephone repair and installation crews around smoggy Los Angeles.