Significant savings with geothermal heat pumps

When it comes to heating and cooling homes, schools and even penguins at Woodland Park Zoo, a growing number of people are turning to a source as old as the Earth itself: geothermal heat.

"It seems like the floodgates have opened," said Gerard Maloney, owner of Earthheat, a Duvall company that has been installing commercial and residential geothermal systems for more than 10 years. "When [gasoline] hit $4.50 a gallon, the phone started ringing off the hook."

Significant savings

The main attraction of geothermal heat is the savings.

Maloney estimates the cost of running a geothermal system in a 3,000-square-foot house would be about $700 a year, with an equivalent natural-gas system costing as much as $6,000 a year.

But Dave Sjoding, a renewable-energy specialist at Washington State University, said measuring the efficiency of geothermal systems varies because comparisons are affected by differences between types of high-efficiency furnaces, as well as the costs of competing fuels.

One analysis used by Maloney, however, estimates a 70 percent drop in home energy costs.

The Department of Energy estimates ground-source heat pumps use 25 to 50 percent less electricity than conventional heating or cooling systems.

"We're really excited about this," said Monica Lake, project manager for the Woodland Park Zoo's penguin exhibit.

She said the zoo is using a $65,000 grant from Seattle City Light to help fund the $210,000 project. The zoo chose the geothermal system because it requires nearly zero long-term maintenance and because of the energy savings.

There is a catch. A geothermal system costs more to install. Maloney believes that may be the reason why geothermal systems haven't become widely popular.

"Our costs are usually about 50 percent more than conventional equipment," said Maloney, comparing a geothermal system with a high-efficiency furnace, hot-water heater and air-conditioner installation. "That 50 percent you'll generally see back in about five years."

He estimates the cost of providing a conventional natural-gas system, including a furnace, air conditioner and water heater, might be $10,000. A ground-source geothermal system probably would cost $15,000 to $20,000, he said.

Those high upfront costs also are cited as a major barrier by David Clement, Seattle City Light director of resource planning. Additional concerns include the space needed to install underground piping and a general ignorance that the systems even exist.

"Another thing that puts a damper on it is we enjoy relatively low-cost electricity," he said. "It's also partly a function of how they [potential buyers] just haven't seen much of it."

If I want to know more about geothermal heat - 50+ FAQs about Geothermal Heat Pumps