Geothermal heat pumps make financial sense, even without government subsidies. Now, with energy in focus, ground-source heat pumps are winning fans:
The systems use a network of water-filled pipes laid either horizontally (6 feet under) or vertically (often 200 to 300 feet down), that attach to a heat exchanger.The technology can be used almost anywhere, on any type of building. “We’ve got them all the way from Texas to the Arctic Circle,” said Mr. Bose, a professor of engineering technology at Oklahoma State University in Stillwater.
And even without financial incentives from the government or energy utilities, says John Shonder of the Energy Department’s Oak Ridge National Laboratory in Tennessee, “ground-source heat pumps have the lowest life-cycle costs in several cost studies that I’ve done” of heating and air-conditioning systems. (For details on incentives, see www.dsireusa.org.)
The systems pay for themselves in three to eight years, depending on “location and energy prices,” Mr. Shonder said.
In fact, heat pump systems may offer the greatest savings to the owners of commercial buildings, says John W. Lund, director of the Geo-Heat Center at the Oregon Institute of Technology. “For commercial buildings, where you have a fairly large heating and cooling load, the payback period could be two to three years.”
Though no comprehensive survey of the heat pump sector exists, Energy Department statistics on units shipped tell a striking story. In 2003, system manufacturers shipped 36,439 units. In 2006, the last year for which data is available, manufacturers shipped 63,683 units.
(Hat tip to FuturePundit.)