mail icon Get the latest news and stories about geothermal straight to your inbox.

dandelion logo

Coefficient of Performance (COP)

What is COP?

Coefficient of Performance, or COP, is a measure of efficiency for HVAC systems based on their heating output. Every system requires some form of energy input to run the system, but not every system can make the most of the inputted energy to produce greater output. COP is an objective method to measure and compare different HVAC systems.

Why does COP matter?

COP is calculated by dividing the energy output by the energy input. The greater the COP, the more efficient your system is. An HVAC system with a COP of at least 1 is producing more energy than is required to run it.

Put simply, the more efficient your HVAC system is, the more bang you’ll get for your buck! Choosing an efficient HVAC system with a higher COP will help you minimize your monthly heating bills.

How does a geothermal COP compare to those of other HVAC systems?

The COP for any HVAC system can be found in its technical specifications guide, and it is a powerful tool for comparing and contrasting your options. If price, convenience, installation, and other factors are all comparable across HVAC systems, then COP can be an important tiebreaker in your search.

Heat pumps are currently the only residential heating and cooling options with COP above 1. Dandelion’s geothermal heat pump has a COP of 4, meaning that for every 1 unit of energy inputted, it produces 4 units of energy to heat and cool your home. In contrast, other HVAC systems barely break even at a COP of 1, or, in many cases, they actually consume more energy than they produce.

What’s the difference between COP and EER?

Energy Efficiency Ratio, or EER, is another measure of efficiency for HVAC systems that’s used for calculating cooling output or AC. In contrast, the term COP is used for measuring heating output.

EER is calculated using the imperial system, and COP is calculated using the metric system, so the values look a little different. However, since both values are unitless ratios, we can easily convert between the two: a COP of 1 is equivalent to an EER of 3.4.

What’s the difference between COP and AFUE?

Annual Fuel Utilization Efficiency, or AFUE, is a measure of efficiency specifically used for comparing furnaces. This value is calculated by dividing the inputted fuel in a furnace by the usable heat that it produces to heat your home.

In other words, COP and AFUE are both calculated using a very similar division formula, the only difference being terminology. Comparing against categories, even the most sustainable Energy Star furnaces have an AFUE of only 85% or 90%, which is less than the break-even value of 100% (or the equivalent COP value of 1).

Read more about Dandelion geothermal efficiency and pricing here.