Lone Tree, Colorado, Is Going Geothermal! Denver Geothermal Heating has definitely had a hand in that! We're a heating and cooling contractor who’s specialty is installing and servicing geothermal systems right here in Lone Tree, Colorado. Area homeowners trust us for ... our experienced, knowledgeable staff our proficient geothermal installation and service capabilities the planning assistance and advice we provide - to help Lone Tree customers maximize the potential in their geothermal installations If you've been considering going geothermal, contact Denver Geothermal Heating today, Lone Tree's first-choice geothermal contractor. (For a preview of the kind savings your family could be getting with a geothermal heating and cooling system, try our simple Geothermal Savings Calculator.)