Maybe not the first thing that comes to mind when considering energy upgrades to your existing or soon to be new home, but geothermally sourced energy deserves a hard look. For example, this sustainable technology can reduce energy consumption by 80 % and deliver efficiencies of up to 500 %, while eliminating the need for natural gas, fossil-fuel burning furnaces and boiler systems. Sounding good? Now add environmentally clean, safe, efficient AND cost-effective to the list of benefits!

Here’s how it all works. A geothermal system, also known as ground-source heating and cooling, uses renewable energy from the earth to provide cost/energy efficient year-round heating, cooling and hot water for new homes and in some cases, existing homes. A relatively small amount of electrical energy would still be required to power the geothermal pumps and compressor, which could be drawn from the electrical “grid”, or even better, from a solar or wind generated source.

Beneath the frost-line, the temperature of the earth remains a relatively constant 6-8 degrees Celcius year-round. To extract that heat, bore-holes of about 3-5” in diameter,

200-300 feet deep and spaced 15-20 feet apart would have high-density polyethylene pipe inserted which would circulate a “ground-loop” fluid mixture of water and anti-freeze that absorbs heat from the ground. A series of bore-holes would be trenched together to deliver the heated fluid to an interior mechanical room heat pump containing a refrigerant which extracts the energy from the fluid. The refrigerant then changes from a liquid state to a vapor, which, when injected into a compressor, is compressed, drastically increasing the temperature. Through a heat exchanger, this hot vapor refrigerant then releases its heat for use in the home.

Meanwhile, the temperature of the bore-hole fluid has dropped to below zero degrees Celcius and is pumped back into the ground to begin the heat collection cycle over again. The mechanical room heat pump can also work in reverse for cooling purposes by extracting heat from the warm air inside the home and dumping it into the much cooler ground.

In certain cases, hybrid systems can be designed with boilers providing “back-up” heat, but technically, geothermal has the capacity to deliver 100 % of home heating and cooling needs!