Kilian Herrington doesn't need one of those expensive new hybrid cars. He has a gas-powered car he drives on long trips and a 1991 Geo Metro he fitted with an electric motor for daily use.

"I like to avoid using gasoline, so I bought the Geo and converted it about five years ago," says Herrington.

Working with an electric motor dealer in California, Herrington bought an electric traction motor made by Advanced DC Motors, East Syracuse, N.Y. It bolted right to the existing transmission. He outfitted the little Geo with nine 12-volt batteries carried in the back seat and trunk. With a full charge, Herrington can drive at up to 50 mph for 20 miles. A recharge takes him about three hours.

"If someone else was doing it, they might want more acceleration, so they would need more batteries," he says. "It fits my purposes. The nice thing about doing it yourself is you can do it the way you want."

Batteries were one place where Herrington spent more than he needed to. The heavy-duty gel cell batteries are linked in series with individual cells in each cylinder. They have lasted well, but he warns that not keeping them charged up can be expensive.

"If you completely discharge a cell, you shorten its life," says Herrington.

One thing Herrington does miss about a gas engine is the heater in the winter. With no heat being given off by the engine, the car gets cold and stays cold. The answer is simple, just like his retrofit.

"I just wear extra heavy, winter clothing," says Herrington.