Nov 5 - McClatchy-Tribune Business News Formerly Knight Ridder/Tribune Business News - Angela Mettler American News, Aberdeen, S.D.

Imagine paying less than 10 cents per square foot to heat and cool your home.

Those are the savings that U.S. Department of Agriculture officials found when a geothermal heat pump system was installed when the building was built two years ago. Heating and cooling the 8,640-square-foot building cost $799.84 in a year -- or about $66.65 per month.

A geothermal heat pump system brings heat from the earth into a building in the winter, and puts heat from a building back into the earth in the summer.

Bill Hinds, co-owner of the U.S. Department of Agriculture's building in Aberdeen, said he's glad a geothermal system was installed when the building was built two years ago.

"We've never been happier that we've tried it," he said.

Hinds said the decision to install the system was prompted by rising energy prices. He hesitated at first because of the system's initial cost, but he expects a payback in six to seven years due to the money saved.

Employees are happy with how well the system functions, said Dawn Brandt, county executive director at the local USDA office. The building has five zones that can be set at different temperatures.

"I think, for the most part, everybody's comfortable," she said.

Geothermal energy is one of the most efficient and environmentally friendly ways to heat and cool a home or business, said Travis Sichmeller, an engineer with Mettler Sichmeller Engineering in Aberdeen.

The engineering firm designs geothermal systems for commercial and residential use.

How it works: Although a geothermal system works as well as a furnace or air conditioner, it is built very differently.

To build a geothermal system, a contractor digs wells 180 to 200 feet deep into the ground. Polyethylene pipe containing a biodegradable antifreeze/water mix is placed into the holes and surrounded by a putty-like grout to absorb the earth's heat.

The temperature at that depth is about 47 degrees Fahrenheit year round in South Dakota, Sichmeller said.

The pipe can also be installed horizontally underground or underwater in a nearby pond or lake. In an open loop system, an artesian well is the source of liquid that circulates through the system. Geographic features and location determine which type of system works best for a home or business.

Once heated by the earth, the liquid inside the pipes circulates from the ground into an electric geothermal heat pump inside the building, which removes the heat from the liquid to heat the building.

In the summer, the system works backwards -- the heat pump transfers the building's heat into the liquid, which flows back into the buried pipes, transmitting the heat into the earth.

The polyethylene pipe buried underground is guaranteed for 25 years and expected to last 50 years, Sichmeller said.

Once a geothermal heat pump system is installed, home or business owners must install a special meter to get a reduced price on the electricity used for the system. Northern Electric Cooperative's rate is 3.2 cents per kilowatt hour, and NorthWestern Energy's rate is 4.2 cents per kilowatt hour.

Equivalent prices for traditional heating fuels are 28 cents per therm of natural gas at 90 percent efficiency, 26 cents per gallon of fuel oil at 60 percent efficiency and 26 cents per gallon of propane at 90 percent efficiency.

According to the U.S. Energy Information Administration, in October in South Dakota, the average price of propane was $1.47 per gallon and fuel oil was $1.93 per gallon. Natural gas from NorthWestern Energy was 74 cents per therm on a 150-therm bill.

Sichmeller said that because geothermal systems do not burn fuel, they offer many advantages over traditional methods of heating:

--More energy-efficient -- more than 70 percent of the energy required to heat or cool a home comes from the earth.

--More cost-efficient -- eliminates the need to pay for fuel.

--Safer -- no source of carbon monoxide, no boilers or associated safety devices that might fail, no fossil fuel tanks for storage.

--Unlike furnaces and central air conditioning systems, a geothermal heat pump system has no outdoor unit, which extends its lifespan and eliminates noise.

Initial expense: However, installing a geothermal system is more expensive initially. Stewart Schipke, owner of Fay's Refrigeration and Heating, said a residential geothermal system can cost $7,000 more than a conventional system, depending on the contractor's price for drilling, duct work and other home modifications that may be needed.

But the savings that can be achieved often outweighs the initial cost, Sichmeller said.

"We've never had anybody complain they shouldn't have spent the money or they don't like it," he said.

In addition, the Internal Revenue Service offers a tax credit on all Energy Star-labeled geothermal heat pumps installed in homes. For more information, visit www.energystar.com/taxcredits.

Schipke said geothermal energy has become more popular in homes in the past five years. When Rob Ronayne of Aberdeen built his house four years ago, he installed a geothermal system.

"We worked with an engineer and did some calculations on what natural gas or other heating systems would cost and compared that to geothermal," he said. "Geothermal appeared to have a four- to five-year payback, and geothermal seemed like the right thing to do for the environment."

He said his yearly heating and cooling bill is about a third of what it used to be.

"Our home is just as warm as other homes (we lived in) that were heated more traditionally," he said.

Geothermal systems can also be retrofitted in homes with existing traditional furnace, air conditioning and radiator systems, Sichmeller said.

He said people who own homes with working furnaces, air conditioners or radiators might not want to replace their system until they have to.

"The time to do it is when a piece of equipment is failing," he said.

He said if someone needs to replace heating or cooling equipment or is building a new home or business, a geothermal system is worth looking into.

Many area schools, including Frederick, Britton-Hecla, Wilmot, Langford, Sisseton and Warner have installed geothermal systems in their additions.

Scott Sikkink, the Aberdeen School District's director of buildings and grounds, said geothermal systems will be installed in the Simmons Middle School addition and C.C. Lee Elementary School renovation.

The long-term savings and success in other school districts made geothermal energy an attractive option, he said.

"We can heat and air condition all in one system," he said. "It just seems like the right thing to do for the environment, too."

Other Aberdeen businesses with geothermal systems include the Koehler Office Building, Harr Motors, the restored Burlington Northern Santa Fe Railroad Depot, the snow removal equipment building at the airport and the Aberdeen Eye Clinic.