Although they sound like they are different terms for the same thing, geothermal energy and ground source heat pumps are two different systems, with little in common other than that they are making use of what lies below the surface of the Earth. They do it in very different ways, however.

A geothermal energy system uses heat from below the surface of the earth as an energy source, much like solar panels capture sunlight and convert it into useful energy (electricity or hot water). A geoexchange system with a ground source heat pump (GSHP) is more akin to a hybrid automobile. It is not a method for generating energy, but a method for more efficiently using energy. It still takes energy input to operate a GSHP system, but a GSHP can be as much as 300% to 400% more efficient when compared to highly efficient furnaces, which are typically in the high 90s for efficiency percentage.

Read more of this story »