It’s no secret that heat pumps are energy efficient. They are among the most energy-efficient heating, ventilation and cooling (HVAC) systems on the market. According to the U.S. Department of Energy (DOE), they consume half as much as energy as electric furnaces and baseboard heaters. You can save money by using a heat pump to heat your home during the winter.
When researching heat pumps, you may discover that they are over 100% efficient. Efficiency ratings can vary depending on many different factors. Nonetheless, many heat pumps are 200% to 300% efficient. How do heat pumps achieve over 100% efficiency exactly?
What Efficiency Means
To better understand how heat pumps achieve over 100% efficiency, you must familiarize yourself with the definition of “efficiency.” In the HVAC industry, efficiency is a measurement of how much hot or cool air a system can produce relative to the system’s energy consumption.
All HVAC systems consume energy to produce hot or cool air – and heat pumps are no exception. Efficiency represents the ratio of a system’s consumed energy to its thermal output. A gas furnace that’s 98% efficient, for instance, will convert 98% of the natural gas it consumes into heat. A heat pump that’s 300% efficient, on the other hand, will convert 300% of the electricity it consumes into heat.
Heat Pumps Extract Heat
Heat pumps achieve over 100% efficiency because they extract heat from the outdoors. This means they produce more heat relative to their energy consumption. A heat pump that’s 200% efficient will produce twice as much heat as the amount of energy it consumes.
The exceptionally high efficiency ratings of heat pumps can be attributed to their operations. They don’t produce heat directly from burning natural gas or powering an electric heating element. While gas furnaces and electric furnaces use these methods, heat pumps use an entirely different method to produce heat.
Heat pumps work by extracting heat from the outdoors. There are ground-sourced and air-sourced heat pumps. The former extracts heat from the ground, whereas the latter extracts heat from the air. Heat pumps operate like air conditioning systems, but the direction of their refrigerant can change to accommodate both cooling and heating.
Regardless of the specific source, heat pumps pull or extract heat from the outdoors. They still consume electricity, but they don’t directly convert this electricity. Heat pumps use electricity to extract heat from the outdoors, which allows for an efficiency of over 100%.