To bring down the house's energy use, the team installed geothermal heating and cooling.

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The house was also designed to consume minimal energy and incorporates a number environmentally friendly features, including geothermal heating and cooling and recycled tile floors and countertops.

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The former Mary Kay home was redone by the current owner: New flooring, paint, updated kitchen and geothermal system for heating and cooling.

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The firm said the construction phase would create hundreds of new jobs while the surface mine site could be tapped for geothermal energy to provide heating and cooling for the homes.

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Craig Funke, chief executive and part owner of Equiguard, which provides warranties to the heating and cooling industries, says geothermal units' failure rates, including both equipment failure and bungled installs, are equal to those of conventional equipment.

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