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...
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...
Re:The Third Phase of Clean Energy Will Be Most Disruptive Yet
by bluGill on Wednesday April 03, 2019 @01:53PM
(#19565524)
A modern furnace is only expected to last 20 years or so. Upgrading equipment is a solution is the upgrade isn't too expensive. I've looked into geothermo heat pumps a few times in the past, and they never worked out because of cost. I'm thinking seriously about replacing my current (working) furnace with a heat pump though just because I want some zoning that the natural gas furnace cannot do.
You can upgrade equipment but that's not even remotely a solution to decarbonize at the rates we apparently need. There are lots of quadrillion BTUs that need to be decarbonized, and upgrades alone won't get us there. We need clean energy sources to ramp up and replace natural gas, oil, and coal.