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A comment on The Third Phase of Clean Energy Will Be Most Disruptive Yet. Parent comment

Re:The Third Phase of Clean Energy Will Be Most Disruptive Yet by dashundchen on Wednesday April 03, 2019 @02:04PM (#19565622)
> I don't think that's quite the right energy balance for heat pumps ;)

It's exactly right. A good heat pump will have a coefficient of performance (COP) of 5, which means for every watt of electricity put in, 5 watts of heat is moved from outside to inside - effectively an efficiency of 500%. While resistance electric heat and fossil fuel can never give more heat than the energy put in.

https://en.wikipedia.org/wiki/Heat_pump#Performance_consider...

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Re:The Third Phase of Clean Energy Will Be Most Disruptive Yet by zaroth on Wednesday April 03, 2019 @05:33PM (#19567424)
5 is highly optimistic. Real world average efficiency is closer to 2.5 (lower in colder climates) because there are a lot of variables you have to get exactly right to hit that 5 COP, and they very rarely line up.

Source: I have a Fujitsu 36K BTU cold climate 4-zone system installed two years ago to replace electric baseboard heat. [1]

[1] - http://www.fujitsugeneral.com/us/products/multi/2-3-4rooms/a...

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