SACE | Southern Alliance for Clean Energy

Increase Home Efficiency with Geothermal System


Some drill for oil, others drill for heat. In their never-ending quest to create the model energy efficient, clean energy home, Stephen and Libby Smith have added a geoexchange heating and cooling system to their residence in Knoxville, Tennessee. This adds to their existing electricity generating residential solar system, one of the largest of its kind in the TVA Generation Partners program.

“Fifty years ago, Jed Clampett of the popular TV series, the Beverly Hillbillies, drilled for oil in the Ozark Mountains just to the west of Tennessee. If that series were made today, the Clampett’s would have been drilling for clean and renewable geothermal energy,” said Stephen A. Smith, executive director of Southern Alliance for Clean Energy. “Just like solar, geoexchange and geothermal heating and cooling systems are a key part of the green economy – and more companies catering to the demand for these systems are springing up.”

The geoexchange system is decreasing carbon emissions and other air pollution, contributing less to mountain top removal mining and coal ash waste from burning coal, or nuclear waste piling up at reactor sites, and hot water which gets dumped into our rivers from running nuclear power plants. Check out this video documenting the Smith’s geothermal system installation.

The Smiths chose Knoxville’s Pioneer Heating and Cooling to install a state-of-art WaterFurnace Envision system – rated as number one in energy efficiency because they can deliver an astounding five units of energy for every unit of electrical energy used. Compare that to even the best ordinary gas system that delivers less than one unit of energy for every unit it consumes. That translates into an efficiency rating of 500 percent, compared to the most efficient gas furnace, which rates only 94 percent.

The geothermal system design actually provides three services: cooling, heating and an improvement in the efficiency of our existing solar hot water system. It will play a key role in getting the Smith home closer to net zero energy.

“Not only are we thrilled to reduce our carbon footprint and utility bills even more, but this will marry with our existing solar hot water system to produce additional hot water from the sun’s energy,” says Smith. The system involves the use of geoexchange heat pump technology to tap the solar energy in the earth’s surface to drive the home’s heating and air conditioning system. The result is a green or natural heat pump that saves energy and benefits the environment.

The Smiths will save an estimated 70% on heating, cooling, and hot water costs.?? In addition to saving energy dollars, a new tax credit is now available for home and commercial building owners who install geothermal heating and cooling systems through the Energy Improvement and Extension Act of 2008 (H.R. 1424). The incentive program offers a onetime tax credit of 30% of the total investment for homeowners who install residential ground loop or ground water geothermal heat pumps. Smith says, “the Knoxville Utility Board together with TVA also now provide low interest loans of up to $12,500 for systems like this, and they allow you to pay it back on your utility bill.

Once the geoexchange system is in place, the Smith home will run on: a solar electric and a separate solar thermal hot water system, a geoexchange heating and cooling system, and solar tubes which provide natural daylight in their home. Stephen and Libby Smith hope the home will continue to serve as an example within their community and the nation.

Click here to read Stephen Smith’s blog post discussing interesting details surrounding the system’s installation. You can follow the Smith’s entire home project on the Southern Alliance for Clean Energy blog.