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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It is the only place we saw that uses geothermal energy for heating and hot water.

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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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The technology paper covers 10 technologies: bioenergy for electricity and heat, biofuels, geothermal energy, hydropower, ocean energy, solar energy (PV, concentrating solar, and solar heating), and wind (onshore and offshore).

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As well as using wind turbines to provide electricity, and straw-burning plants to provide heating, some islanders have solar panels on their roofs and others warm their homes using geothermal energy and the heat given off by fresh cow's milk.

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David Dwyer, the contractor who built the Yerke family's home and installed their geothermal system, says that if you have an old and drafty house you should, before putting in a fancy heating system, put in new windows, seal leaks and add insulation.

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