Editing Coefficient of performance (section)

{{short description|Ratio of useful heating or cooling provided to work required}}
The '''coefficient of performance''' or '''COP''' (sometimes '''CP''' or '''CoP''') of a [[Heat pump and refrigeration cycle|heat pump, refrigerator or air conditioning system]] is a ratio of useful heating or cooling provided to work (energy) required.<ref>{{cite web |url=http://www.tetech.com/temodules/graphs/instructions.pdf |title=Archived copy |access-date=2013-10-16 |url-status=dead |archive-url=https://web.archive.org/web/20130124080037/http://www.tetech.com/temodules/graphs/instructions.pdf |archive-date=2013-01-24 }}</ref><ref>{{Cite web|archive-url=https://web.archive.org/web/20140628003757/https://us.grundfos.com/service-support/encyclopedia-search/cop-coefficient-ofperformance.html|archive-date=2014-06-28|url=https://us.grundfos.com/service-support/encyclopedia-search/cop-coefficient-ofperformance.html|title=COP (Coefficient of performance)|website=us.grundfos.com|language=en-US|access-date=2019-04-08}}</ref> Higher COPs equate to higher efficiency, lower energy (power) consumption and thus lower operating costs. The COP is used in [[thermodynamics]].

The COP usually exceeds 1, especially in heat pumps, because instead of just converting work to heat (which, if 100% efficient, would be a COP of 1), it pumps additional heat from a heat source to where the heat is required. Most air conditioners have a COP of 3.5 to 5.<ref>{{cite web| title=Air Conditioning EER and COP | url=https://airconditioninggoldcoast.com/air-conditioning-eer-and-cop/ | access-date=9 October 2024}}</ref> Less work is required to move heat than for conversion into heat, and because of this, heat pumps, air conditioners and refrigeration systems can have a coefficient of performance greater than one. 

The COP is highly dependent on operating conditions, especially absolute temperature and relative temperature between sink and system, and is often graphed or averaged against expected conditions.<ref>{{cite web |url=http://www.tetech.com/temodules/graphs/HP-199-1.4-0.8.pdf |title=Archived copy |access-date=2013-10-16 |url-status=dead |archive-url=https://web.archive.org/web/20090107132318/http://www.tetech.com/temodules/graphs/HP-199-1.4-0.8.pdf |archive-date=2009-01-07 }}</ref> 

Performance of [[absorption refrigerator]] chillers is typically much lower, as they are not heat pumps relying on compression, but instead rely on chemical reactions driven by heat.<ref>{{cite web |title=Coefficient of Performance - Measuring Efficiency in HVAC Systems |url=https://www.fargoheatingandcooling.com/coefficient-of-performance-measuring-efficiency-in-hvac-systems/ |website=Fargo Heating and Cooling |date=6 November 2023 |access-date=November 6, 2023}}</ref>