SHARON, Conn. -- The oldest natural power source of all is water.

Bill Kelsey said he and his wife live out in the woods, a long way from any power lines. So when he needed a source of power for his home, he said he looked into his back yard.

“All the drainage from Macedonia State Park is down there,” Kelsey said.

He said he drew water from the pond with a 4-inch pipe and ran it underground to keep it from freezing, and then hooked it up to a generator that's turned by the rushing water.

“So far, this one's been running two years without stopping, all the time, 24/7,” Kelsey said. “The only time it stops is in August because the water coming down the brook slows down.”

Kelsey said he uses some solar power in the summer.

Another problem he said he had to overcome was what to do with the excess electricity he generates. Once his batteries are full, he said he pumps the excess into a heavy-duty water heater.

Before putting in the system 20 years ago, Kelsey said he had to calculate his energy needs and work off that, changing the DC power into AC with an inverter and some other basic electronics.

One downside, he said, is lightning. He said when the system gets hit, it gets fried.

But since putting in a capacitor, he said he hasn’t had a problem.

“That's as basic as you can get, simple, and there are lots of streams here in Connecticut, and you only need 30 feet of drop,” said Kelsey.

He said his system cost about $3,500 in equipment and labor.