What is a ground source heat pump?

Essentially, ground source (geothermal) heat pump is an advanced air conditioner, which can run in either direction (that is – it can supply both heat and cold) and has dramatically improved efficiency by utilizing earth’s thermal energy extracted from the ground by using ground heat exchanger.

Ground source (geothermal) heat pumps operate on a principal that when an inert gas (such as freon) is compressed, it gives of cold, and when it’s de-compressed, it gives off heat.  Basically, ground source heat pumps are advanced Air Heat pumps. Air heat pump was invented in Finland where winters are VERY cold, and to supplement the main heating systems, Finns began to use air heat pumps.

Speaking in very general therms, using air heat pump is twice as efficient as using electric baseboard heating. By adding geothermal energy to the mix, your efficiency doubles yet again. Therefore ground source heat pumps are arguably the most efficient heating (and cooling) systems available today. Basically, you are getting a Dollar worth of heat, while paying only 25 Cents.

How heat pump works – video:

Types of heat pumps:

There are essentially two types of heat pumps: Air Heat Pump and Ground Source / Geothermal Heat Pump. Biggest difference between the two is efficiency. Ground source heat pumps are on average twice as efficient as air heat pumps, since they use the thermal energy of the earth crust to increase energy output, while decreasing energy input.

Benefits of using geothermal (ground source) heat pump.

Ground source heat pumps add tremendous benefits to your house, by increasing the energy efficiency of your heating and cooling systems by 2-3 times, and as a result decreasing your bills to heat your house in the winter and cool it in the summer by the same two to three times.

Think of it this way: Let’s take a hypothetical house with a geothermal heating system say the temperature outside is 30 degrees Fahrenheit (or near zero degrees Celsius, which is a freezing point for water), temperature below earth’s freeze-depth is constant, at about 50-55 degrees F, and we want to heat up our house to about 70 degrees F. Therefore we need to raise the temperature of outside air by 40 degree. If we add up the geothermal energy into the mixture, our “starting temperature” is now 55 degrees. So now we need to increase the air temperature by only 15 degrees, instead of 40. That is actually over 60% increase of efficiency. Use temperature conversion calculator to quickly convert temperatures between Celsius and Fahrenheit.

Why geothermal heating and cooling systems are not so “popular”?

If geothermal heating is so advanced and efficient, why are we still using oil, gas and electricity to heat and cool our homes? Why not every house or large apartment building is using ground source heap pumps instead of those inefficient and polluting furnaces and boilers? Main reason for this is the cost of a geothermal heating systems. Average geothermal heating and cooling system will run you about $30000. And heat pump, while not the most expensive item on the total price list for a geothermal heating system, certainly costs a lot, and adds significant chunk to the geothermal price tag.

Ground source heat pump prices:

On average, you can expect to pay anywhere from $5000 to $15000+ for a heat pump alone, depending on the number of BTU it can produce.