REI: RENEW Energy Initiative

Geothermal Exchange

Geothermal exchange heating and cooling is an exceptionally high-efficiency, highly reliable way to heat and cool a building.  By exchanging heat energy with the constant temperature reservoir of stored solar heat lying just a few feet underground, this process typically delivers 3 – 6 units of heat energy for each unit of electrical energy consumed, thus yielding tremendous heating and cooling cost savings.  The process also reverses to provide very efficient summertime air conditioning.  In addition to cost savings, geothermal exchange involves no in-building combustion, produces no direct carbon footprint nor air pollution, needs very little maintenance, and can meet most residential and general commercial building heating and cooling needs. Share your thoughts, experiences and questions through the Discussion blog below.


Another Solar Energy?

Surprisingly, geothermal exchange actually uses solar heat stored in the first 1000 – 1500 yards of depth in the earth’s surface.  During cold weather, some of this stored heat is extracted and concentrated by a geothermal heat pump, and is used to heat a building and/or hot water, providing 24x7 heating by solar heat.  Modern GHPs can deliver between 3 to 6 kilowatts of heat energy for every kilowatt of electrical energy used by the heat pump.  In warm weather, a GHP will reverse the process, very efficiently cooling the building while also providing “free” hot water and partially replacing the heat energy extracted from the ground during the winter.

Due to a number of reasons, very much including the relatively high cost of electricity compared to what had historically been a low cost of fossil fuel, geothermal exchange heating and cooling wasn't very attractive in New England until recently.  Geothermal exchange eliminates the need for in-building combustion and the resulting hazards, requires very low maintenance, and can meet most general commercial and residential HVAC needs. Contact our office to get involved with a geothermal exchange work-group and contribute your thoughts to the discussion blog below. 


1. Dennis McCarthy, Thursday, August 07, 2014, 16:46:

Geothermal exchange is the preferred technology and is sometimes confused with geothermal energy which is more prevalent in the western U.S.