[Colorado Doug]

He left out geothermal heat pumps for heating and air conditioning buildings. I just installed one in my house and it works great. It works like a regular heat pump except, instead of using a finned heat exchanger trying to cool freon with hot air on a 106 degree day it uses either water or a loop of coolant in an underground pipe. The ground is relatively cool in the summer (about 55 degrees f) and likewise, relatively warm in the winter. The system simply reverses itself in the winter for heating. In the heat cycle, the air comes out of the ducts at about 115 degrees, About 50 degrees in ac mode. The ground loop kicks the efficiency way up from an old fashioned air to freon heat exchanger. The heat/cool in the earth is free. All I pay for is the energy needed to condense it and get it into my house. My C.O.P. is better than 3 and it makes free hot water in the summer time.

[BearCub]

He left out geothermal heat pumps for heating and air conditioning buildings. I just installed one in my house and it works great. It works like a regular heat pump except, instead of using a finned heat exchanger trying to cool freon with hot air on a 106 degree day it uses either water or a loop of coolant in an underground pipe. The ground is relatively cool in the summer (about 55 degrees f) and likewise, relatively warm in the winter

Curious - how much do these things cost to install? How far down do they go?