Frequently asked questions re Geothermal/Geoexchange:
What is Geoexchange?
Geoexchange is a method of heating and cooling buildings, and providing domestic hot water.
The earth's natural heat is collected using a series of pipes in the ground, called a loop.
The loop carries a benign thermal transfer fluid that picks up the heat from the ground and
carries it into the house where a heat pump raises the temperature and then distributes it
throughout the building.
In the summer the system is reversed. Heat is taken out of the home and transferred to the ground where it is stored until it can be used to heat the home.
What is solar thermal?
Solar thermal technology is most often used to heat domestic hot water. Solar collectors on
the roof gather heat from the sun. A series of tubes behind the panel carry fluid that transfer
the heat from the collector down to the domestic hot water tank. The heat is transferred to the
water tank through a heat exchanger.
Is the technology reliable?
Geoexchange has been used in Europe for well over 50 years, and in North America for about 30.
Heat pumps have an expected life of approximately 20 years, which is significantly longer than
that of a furnace (12 to 15 years). As long as the systems are designed and installed properly,
they are expected to run trouble-free for decades. The only real requirement is changing the
filters and periodic checks, just as with a furnace.
Can the technology be used effectively in the Canadian climate?
The extremes of Canada's climate make it ideal for geoexchange. The temperature of the ground
beneath the earth's surface remains relatively constant throughout the year, even though the
outdoor air temperature may fluctuate greatly with the change of seasons. This stable ground
temperature allows geoexchange systems to use it as both a sink and a source, putting in heat
in the summer, and taking it out in the winter. And because it does so much more energy
efficiently than a furnace or an air conditioner, it is very cost effective.
Does Geothermal/Geoexchange cost more?
A Geothermal (Geoexchange) system will cost more on the surface than a conventional system, but
the homeowner will probably still be saving money from the first day they move into their new home.
By including the cost of a Geothermal system in their mortgage their monthly payments will
increase. However, their monthly utility payments will decrease, probably even more. The result is
that the homeowner will likely save at least $50 per month, and as the price of energy increases so
will the savings.
Do Geothermal systems also heat water?
Yes. Using a desuperheater the heat from the compressor in the heat pump can be used to provide heat
to the domestic hot water.
Will Geothermal/Geoexchange also provide air conditioning?
Yes, a system will provide all of the air conditioning needs of the home. And even better, it does it
using the same equipment it uses to heat the home. There are no noisy and unsightly air conditioners in
the yard, no extra maintenance, and no additional equipment purchases.
