Geothermal Myth #1: Geothermal Heat Pumps Don’t Work In Extreme Cold
With all of the information available on the web, we wanted to take the time to dispel a few of the myths surrounding geothermal heat pumps in a three part series. Today, Geothermal Myth #1: They Don’t Work in the Extreme Cold.
The myth that geothermal heat pumps do not work in cases of extreme cold is often derived from the fact that standard air source heat pumps do perform poorly in below freezing temperatures. A ground source heat pump is NOT an air-to-air heat pump.
A number of homeowners in the Northeast have complained that air-source heat pumps do not have the ability to produce enough warm air when the outdoor temperature drops below freezing (which it often does during those brutal northeast winters). The differences is that when the outside temperature is below freezing (say 15 degrees Fahrenheit) the temperature underground is still somewhere between 45 and 55 degrees.
So remember that 400% efficiency that your geothermal heat pump has? Well it’s still there! Just because the temperature outside drops does not mean you need to worry about your geothermal heat pump’s ability to keep you warm. Your geothermal heating will function however it simply needs to produce more heat to keep up (meaning it will run longer). Most systems will have an auxiliary heat backup (electric) to ensure the system always provides sufficient heat. This auxiliary heat should only come on during the coldest days of the year. Problems arise when the auxiliary heat runs constantly – this would result in a very high electric bill.
You will find many upset homeowners who curse geothermal systems. We certainly will not hide the fact that there have been plenty of disastrous installations out there by inexperienced contractors. You’ll find these stories in the comments below. These situations are extremely unfortunate and the frustrations by these homeowners are completely warranted, however, its not the technology – its the design. When a system is not designed correctly it fails – think of it like trying to tow a large boat with a Honda Civic. Finding a quality geothermal contractor is absolutely the key to geothermal happiness. Ask for references from systems the same company installed 5-10 years ago, if they don’t have them then don’t buy!