News

St. Louis is geothermal hot spot


> Sep 18 - McClatchy-Tribune Regional News - Tim Bryant St. Louis
> Post-Dispatch
>
> St. Louis' temperate climate makes the region an ideal ground
> zero -- so to speak -- for geothermal heating and cooling systems that
> drastically slash home energy costs, experts say.
>
> Among the growing number of users here is Gary Pedersen, a
> retired Bayer Corp. policy analyst. He says the utility costs at his
> two- year-old Kirkwood home are half those at his nearly identical
> former home in Eureka, which had a conventional forced-air system.
>
> Pedersen, 69, said his geothermal system "was a little bit more
> expensive, but over the long run it will more than pay for itself."
>
> Architects, builders and engineers familiar with geothermal
> systems said this part of the Midwest has limitless potential for
> low-cost heating and cooling.
>
> Geothermal energy currently provides a sliver of the nation's
> residential needs. But if enough homes use free energy stored in the
> earth, utilities will no longer need to continue building costly and
> polluting power plants, geothermal advocates say.
>
> Among them is Yunsheng "Shawn" Xu, an associate professor of
> engineering at the University of Missouri who is designing a
> geothermal system to drop his home's energy costs to zero. He will
> install the system in his family's house, which he plans to start
> building next month west of Columbia. Xu (pronounced "shoe") met this
> week with the project's architect, Tom Tyler, founder of Answers Inc.,
> and one of the home's builders, Matt Belcher, president of Belcher
> Homes, both of St. Louis.
>
> Orienting Xu's 2,600-square-foot home on the 15-acre semirural
> site to make the best use of the sun's effects and figuring out where
> to place rooms consumed part of the meeting. Xu, 47, is in charge of
> the home's geothermal system.
>
> It will be infinitesimally smaller than the ones he helped design
> for the Olympic Village and the 91,000-seat "Bird's Next" stadium
> built for the Beijing Games last year. Huge or small, geothermal
> systems are simple. They work like this:
>
> -- A fluid -- mostly water -- circulates through coils of plastic
> pipe placed horizontally a few feet below the ground surface or in
> holes bored 150 to 200 feet deep.
>
> -- In winter, the fluid warmed underground is pumped from the
> earth and after heated further by a compressor is distributed through
> a building's conventional duct work.
>
> -- In summer, the process is reversed. The geothermal coils
> return the building's interior heat to the ground, much the way a
> refrigerator sheds heat through its coils. The rule of thumb is that a
> geothermal system is at least 70 percent more efficient than a natural
> gas furnace.
>
> Experts say the St. Louis region is especially geothermal
> friendly because its infrequent triple-digit temperature swings over a
> given year mean the ground temperature just a few feet below the
> surface is a constant 60 degrees or so. As a result, heating and
> cooling demands on a geothermal system are low.
>
> Xu will bury geothermal coils beneath his home's gravel driveway
> and boost efficiency with a solar panel that will provide the
> electricity needed to power the system's small pump. Lots of wall and
> roof insulation, plus moveable exterior window blinds also will help
> cut reliance on utility-supplied electricity to zero, he said.
>
> "It'll be nice," Xu added.
>
> He said the geothermal system's cost -- roughly double that a
> conventional heating and cooling system -- helps push his three-
> bedroom home's construction budget to about $400,000. At about $154
> per square feet, the cost remains solidly in the range of custom-built
> homes in the St. Louis area. He plans to recoup 30 percent of the
> geothermal system's cost through the federal tax credit that applies
> to geothermal systems as well as solar panels, solar water heaters,
> small wind energy systems and fuel cells.
>
> Tyler and Belcher predict the number of geothermal homes in the
> St.
> Louis area will grow. St. Louis has "a certain sense of practicality
> that allows it to adapt some of these technologies," Tyler said. In
> the St. Louis area, using the earth to heat and cool homes is more
> efficient than trying to do the job with solar or wind energy, he
> added.
>
> Belcher said a few local lenders are beginning to realize that
> geothermal systems enhance a home's value. St. Louis electricity costs
> are relatively low but will inevitably rise, making super-energy-
> efficient homes even more desirable, he added.
>
> "Every time Ameren talks about bumping its rates, it seems like
> my phone rings a little more often," Belcher said.
>
> How many geothermal systems are in homes nationwide is difficult
> to determine, but according to the National Association of Home
> Builders, the number has grown in the past two years, said Calli
> Schmidt, an association spokeswoman.
>
> The government's Energy Information Administration reported in
> July that of the nearly 100 quadrillion BTUs consumed in the United
> States last year, 7 percent came from renewable energy sources. Of
> that amount, 5 percent came from geothermal energy. Though still
> small, geothermal energy use doubled between 1995 and 2007, the Census
> Bureau has reported.
>
> Pedersen said he and his wife, Sharon, appreciate their system's
> lack of a noisy outside air-conditioning compressor and the whisper of
> quiet fans that gently move air to and from the geothermal coils.
> Summer cooling costs are low, and "in the winter, we pretty much get
> everything out of the earth," he said.