Super energy efficient homes go tankless

LAGOS, Nigeria - Oct 11 (The Associated Press)

A cluster of prototype Southern California homes are further evidence that energy efficiency is more than a few added inches of fluffy insulation.

An energy consultant who oversaw planning for 73 energy-efficient homes says insulation is just one factor among many to cumulatively reduce household energy use by up to 60 percent.

In addition to solar panels and other state-of-the-art features, one of Rob Hammon's unsung heroes in pursuit of lower energy usage: tankless water heaters.

"You have to look at lots of sources to save energy when you want the most efficient house," says Hammon of ConSol, a Stockton, Calif., energy consulting firm. "When you can trim 50 to 70 percent of your water heating costs, you do it." The water heater Hammon specified, by Georgia-based Rinnai Corp., is a departure from the nonstop heat-reheat cycles of traditional water tanks that keep water warm whether it is used or not.

"We just didn't want a water heater that is constantly losing temperature and reheating," says Hammon. "The tankless system heats water without the energy loss." The Rinnai system heats water only after a faucet is turned. Water passes over a heating element and, in three to five seconds, is heated to a preset temperature determined by the customer. This means energy is used only as water is needed and avoids the loss of what Hammon calls "standby loss" or water that is not used but remains hot in a standard water tank.

Homeowners using breadbox-sized tankless systems can expect to pare 50 percent of their cost for gas and 70 percent of electric fees. Water heating typically ranges from 17 to 25 percent or more of annual home energy costs.

The 73 homes are part of a U.S. Department of Energy certified development in Fallbrook, Calif. The development, called WillowCreek at Peppertree Park, is labeled a Zero Energy Home community.

Although the homes do not literally use zero energy, the homes are designed to reduce energy and even produce it through use of solar panels to produce electricity and heat. Appliances, windows and exterior products were all chosen for their contributions to energy efficiency and conservation.

Aside from contributing to overall energy savings, Hammon sees other pluses to the tankless heaters. He says in survey after survey, consumers have indicated energy efficiency is an important issue. The problem, Hammon says, is that until now homeowners haven't backed up the claim with their buying habits.

"With the blackouts and brownouts in the Northeast and West in the last few years and overall hikes in energy costs, consumers are starting to become aware of the long term importance of energy savings," he says. And low energy homes are a competitive advantage when the time comes to resell a home.

While it is true real estate values hinge on "location, location, location," Hammon says if a consumer is weighing the pluses of competing homes and with all things being equal, high efficiency factors may well tip the scales in favor of the energy saving home. The small tankless water heaters don't need a separate utility room or other significant space. It's an important consideration in areas with high per-square-foot construction costs.