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COP (coefficient of performance)

COP is the heat a heat pump delivers divided by the electricity it uses, at one set of conditions.

Editorial staffEdited by heatpumpwiki

History 1

COP (coefficient of performance) is heat output divided by electrical input, in the same units. The federal test procedure defines it as "the ratio of the average rate of space heating delivered to the average rate of electrical energy consumed by the heat pump," and notes it is "a dimensionless quantity."Source 1

NRCan's example: "if a heat pump used 1kW of electrical energy to transfer 3 kW of heat, the COP would be 3."Source 2

COP changes with outdoor temperature. NRCan gives typical air-source ranges of 2.0 to 5.4 at 8°C (46°F) and 1.1 to 3.7 at -8°C (18°F).Source 2 Electric resistance heat delivers about 3,400 Btu per kWh, which corresponds to a COP of 1.Source 3

NEEP's cold-climate specification requires a COP of at least 1.75 at 5°F at maximum capacity.Source 4 See Heat pumps in cold weather. For seasonal efficiency, see HSPF2.

Sources

  1. 1.10 CFR Appendix M1 to Subpart B of Part 430, Uniform Test Method for Measuring the Energy Consumption of Central Air Conditioners and Heat Pumps. Electronic Code of Federal Regulations (U.S. DOE rule). Accessed Oct 25, 2026
  2. 2.Heating and cooling with a heat pump. Natural Resources Canada. Accessed Oct 25, 2026
  3. 3.Air-Source Heat Pumps (archived copy of energy.gov/energysaver/air-source-heat-pumps, captured June 20, 2026). U.S. Department of Energy. Accessed Oct 25, 2026
  4. 4.Cold Climate Air Source Heat Pump Specification, Version 4.0. Northeast Energy Efficiency Partnerships (NEEP). Accessed Oct 25, 2026

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