BY MICHAEL BURKE
Journal Times | Posted: Saturday, April 19, 2008 12:00 am
The earth heats and cools John Schroeder's home in Madison - and he's not sitting on a volcano or a glacier.
Schroeder is one of a growing number of people who are turning to geothermal systems to slash their utility bills and reduce their impact on the planet.
That interest promises to usher in a new industry and new kinds of jobs as more people look for ways to limit their fossil fuel addictions.
Bill Furbish, a water systems specialist with the Wisconsin Department of Natural Resources, says interest in geothermal systems is growing, and for good reason.
"Geothermal is definitely taking off," said the specialist with the Bureau of Drinking Water and Ground Water. "It has very strong advantages to conventional heating and cooling. It offers great energy efficiencies."
A geothermal system operates on the same principle that runs a refrigerator, using heat naturally stored in soil or water to heat and cool homes, businesses and factories.
For an average new house, choosing geothermal over a conventional, 90 percent-efficient furnace and central air-conditioning would raise the cost by $5,000 to $6,000, said Tom Niesen, Gateway Technical College's lead instructor for Gateway's lead instructor for heating, ventilation, air-conditioning and refrigeration.
The payback in lower utility bills would be about five years.
But geothermal has an image problem, said Niesen, who is also division chairman of manufacturing at Gateway. Because the entire system is below ground or inside the home, it's invisible to the public.
That's good protection against vandalism, he noted but added, "It's not sexy like solar or wind power. Our job is to kind of educate the public, so people demand it."
Two new systems
Schroeder said he chose geothermal mainly because he needed a heating system for his swimming pool outbuilding. Geothermal was the only type the City of Madison would allow.
The technology is so rare in Wisconsin, Schroeder said, that none of the Madison building inspectors knew what it was.
Schroeder would have preferred a horizontal, trench system. They are much less expensive, but impossible on a small lot with an existing house.
His only option was a vertical system, which requires deep drilling with special equipment. He bought two systems - one for the pool building and one for his home. With geothermal, refrigerant runs through embedded tubing loops, either drawing warmth from below ground, or taking heat from above and dispersing it underground. The copper tubing in Schroeder's yard extends 100 feet down.
Because of his circumstances, he admits his two systems together were very expensive.
The home's system has only been through one winter so far, but Schroeder said, "It worked like a champ for most of the winter."
Toward the end, the ground was temperature-saturated, and his gas furnace had to lend a hand. But Schroeder estimates the system cut his heating bills by two-thirds to three-fourths.
He said it cut costs by about the same proportion as an air-conditioning system last summer and "worked just fine."
With the size of his investment, Schroeder said it would be hard to recommend someone else do what he did. But for new construction, he said geothermal "absolutely" makes sense.
Racine company
Providing copper-tube, direct-exchange geothermal systems is the basis of the young 2DX2 Geothermal Systems Inc., with its home offices in Racine. The firm is essentially two people: owner Mona Archibald and operator Sheila Milbrath of West Allis.
Milbrath said they chose a Racine base, at Rapids Business Center and Douglas Business Center, for convenience in working with Gateway (see accompanying article).
The company is also one of 20 finalists in the annual Wisconsin Governor's Business Plan Contest. The 2s in its name refer to second-generation geothermal technology, Milbrath explained. The firm contends that makes it the "Cadillac" of ground-based geothermal systems.
Direct exchange does offer the possibility of greater operating efficiency, agreed the DNR's Furbish, although he said he didn't have enough information to confirm that.
The Racine company's other advantage is that it can install vertical geothermal systems where standard well-drilling rigs cannot go - such as Schroeder's yard, and 2DX2 provided that system.
Milbrath said the cost for a vertical system, for an average house, would range from about $18,000-$45,000. Where a horizontal, or trench system, can fit, the cost would be about one-third less.
Milbrath said prime customers for 2DX2 will be commercial, high-volume hot water users such as nursing homes and hotels. The firm says the payback time on investment in a geothermal hot water system would be about two years.
For more information about 2DX2, contact Milbrath at sheilam9@yahoo.com or call (800) 419-2392.
Growing interest
The number of state approvals of individual geothermal installations per year in this decade show the growing interest in the heating and cooling technology:
2001 28
2002 48
2003 39
2004 58
2005 78
2006 139
2007 142
Source: Wisconsin Department of Natural Resources
To see examples of the various types of geothermal installations, visit:
http://www.ecrtech.com/content/interior.asp?section=products&body=earthloop.htm