Geothermal Heat Pumps can save you money
Geothermal (or Water Source) Heat Pumps have been long recognized by the U.S. Department of Energy (DOE) and the Environmental Protection Agency (EPA) as the “most energy efficient and environmentally friendly” systems available. This is a worthy commendation yet the first question for a savvy home owner is often, “what does this mean to me in a practical sense?”
[image_framed_left src=’https://www.specialtyheating.com/wp-content/uploads/2011/07/geothermal.jpg’]Geothermal heat pump systems have two energy ratings, the Coefficient of Performance (COP) and an Energy Efficiency Ratio (EER). Standard air-source heat pumps also have EER ratings making this an easily comparable factor. A good EER for an air-source heat pump would be 12.5 EER (that which qualifies the system for federal and state energy efficiency tax credits). Geothermal heat pumps require a 14.1 EER for a tax credit but often greatly exceed this requirement with ratings up to 27.0! This means the geothermal heat pump would be twice as efficient as the air source heat pump in cooling mode.
The COP is the most straight-forward standard of measurement in that it measures the amount of energy used compared to the amount of energy delivered to your home in heating & cooling. Minimum COP for geothermal heat pump tax credits is 3.4 yet many two-stage geothermal heat pumps achieve ratings up to 4.8 COP when properly designed. This means that for every $1 of energy used by the heat pump, you are effectively receiving $4.80 of heating/cooling energy into your home. Another way to look at it is that the geothermal heat pump is 480% efficient!
Compare this to a standard gas furnace that measures energy efficiency by an Annual Fuel Utilization Ratio (AFUE) and can only achieve up to 98% efficiency in burning fossil fuels. That’s a significant difference! Air-source heat pumps will, as a rule of thumb, achieve 200 – 300% efficiencies, still approximately 30% less than a geothermal heat pump.
A guide to Energy Efficiency Ratings
|AFUE (annual fuel utilization efficiency)||SEER (seasonal energy efficiency ratio)||EER|
(energy efficiency ratio)
(heating seasonal performance factor)
(coefficient of performance)
|Air Source Heat Pumps||n/a||12-21||12-15||7.5 – 10.0||n/a|
|Geothermal Heat Pumps||n/a||n/a||17-27||n/a||3.0 – 5.0|
Geothermal System Advisor
Specialty Heating & Cooling