Staff Photo by Margaret Fenton Julie and Kent Davis recently installed a system that uses warm air in the attic of their Spring Valley home to heat the water in their swimming pool by pumping it through the house. As the cool water travels through the attic, it lowers the temperature of the space as well.

When Kent and Julie Davis built their family’s home in Spring Valley five years ago, innovative energy-efficient solutions were practically impossible to come by.

Today, with more solutions available and energy savings both practical and smart, the family is trying to retrofit the home.

“It’s hard to retrofit a 5-year-old house,” Mr. Davis said. “The real goal is to see what power we can generate to take off the electric grid. We’d like to (eventually) generate as much as we’re consuming.”

Already the family’s switch to almost all fluorescent lights has made a measurable difference, he said.

Earlier this year, in thinking about how to efficiently warm the home’s 20-foot by 40-foot swimming pool, Mr. Davis began to research the idea online.

A man in Wisconsin, it turned out, had done what he had in mind. So he bought both a system for his pool and the rights to be a dealer for the system in the area.

The idea is that the hot air in a home’s attic is used to heat the pool. As it does so, when the heat in the attic decreases, the air-conditioning system cooling the house works less and, in effect, uses less energy.

When the temperature in the attic over the home’s main living area reaches seven degrees above the temperature in the pool, it trips a valve in the pool house and activates the pump.

Water is then pumped from the pool through a flexible, 1.5-inch PVC pipe underground, up through the garage to an attic space, then over to the larger attic space.

In the attic, it feeds through a heat exchanger, then flows back down to the pump in the pool house and into the pool. If the pool reaches 85 degrees, the system kicks off.

Since becoming operational in March, the system has provided $20 to $40 savings in the monthly home electric bill, Mr. Davis said. The pool, essentially, is heated for free, he said.

While he didn’t disclose the cost of the system, he said it would pay for itself in a year to 18 months compared to a $500 to $600 monthly bill if the 30,000-gallon pool was heated with a gas heater.

Mr. Davis, who is fascinated with the technology in his ACT Business Machines company, said he and a friend installed the system themselves in a week of working evenings.

“It wasn’t difficult,” he said, “but we didn’t know what we were getting into.”

On a recent partly cloudy afternoon, the temperature of the water in the pool at the Davis home was 84 degrees. Without the heating system, it would have been 70ish, Mr. Davis said.

“It’s working well,” he said. “I’m very pleased. We have the perfect climate to use something like this.”

Such a system also might heat a hot tub to the maximum of 104 F recommended by the U.S. Product Safety Commission, Mr. Davis said.

The next phase of retrofitting, he said, will be the installation of insulation on the underside of the roof decking. That would be done on all roof peaks of the house except the attic where the pool water is exchanged.

In the future, wind power or geothermal heating and cooling may be possibilities, Mr. Davis said. “I want to see if we can generate enough power to offset what we’re using. I want to see how efficient we can get the house.”