How Your House Works
DRILL AND FILL
Inallers thread pipe into a hole a few inches wide and over 100 feet deep. As wind and solar hog the altenergy spotlight, this technology has remained underground.
pm do-it-yourself
Geothermal: Dig It
by H A R R Y S A W Y E R S
104
OCTOBER 2009
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POPUL ARMECHANICS.COM
www.storemags.com & www.fantamag.com
PHOTOGRAPH BY MERLE HENKENIUS
“You’re not making heat, you’re moving heat,â€? Colorado geothermal inaller Jim Lynch says. Inallations like Lynch’s tap into the earth EFFICIENT AND ECONOMICAL, below the fro line—which always ays around 50 degrees FahrenG E O T H E R M A L H E AT S , C O O L S A N D heit—to reduce a home’s heating and cooling loads. All HVAC syems CUTS FOSSIL-FUEL USE—WITH A require energy-intensive heat movement, a task responsible for over H E A LT H Y R E T U R N O N I N V E S T M E N T. half of the average house’s total energy demand. Geothermal works more eďŹƒciently because the syem’s mild arting point creates an eďŹƒcient shortcut to the target temperature. Imagine a 100-degree Florida day or a 0-degree Michigan night: Spot the syem 50 degrees, and it doesn’t work so hard to get the house comfortable. Unlike wind and solar, geothermal’s power source never varies. Bob Brown, vice president of engineering with equipment maker WaterFurnace, says, “Se ground’s there all the time. It’s great for heating and it’s great for cooling. All I’ve got to do is bury a plaic pipe, put uid in and, lo and behold, I’ve got a great syem.â€?