Comment on Heat-pump water heaters are a winner for the climate — and your wallet
SpaceNoodle@lemmy.world 11 months agoYou still have to create the heat for a water tank, too …
A tankless needs to heat water extremely quickly, which needs a lot more energy. More energy than you can get out of electric heat for a whole house, so most of them are gas.
I guess you might be able to put a bunch of small electric tankless heaters at each hot water tap, but that's a lot more electrical work and points of failure.
That, and each one of those tankless heaters requires its own dedicated 15 or 20 amp circuit so if you install a shitload of them all over the house you’re going to fill up your breaker panel really quickly.
Hell some of them take two or three 40A breakers
Conversion of electricity to heat is 100% efficient.
Heat pumps can achieve an efficiency of over 100%
Not if it’s using a heat pump
In my case, the heat pump is in the basement. So in the summer it's great. It dehumidifies and cools the basement. However in the winter, it's cooling the basement too. So the gas furnace kicks on to heat the basement back up. There's a push-pull there.
However, I have solar, and an excess of electricity credits from it.
So what I've done is put it in high-demand mode which uses more electricity and less heat pump, reducing the push-pull issue.
In the summer I'll put it back in pure heat pump mode.
KinNectar@kbin.run 11 months ago
A heat pump pulls heat from the ambient air and accumulates it in the tank, unlike a conventional water heater which uses combustion or a resistance heater to generate the heat from an energy source. That is why heat pumps are generally much more efficient than other types of water Heaters, including on-demand Heaters which have a very high instantaneous load.
Heat pumps do have their weaknesses though, specifically they lose efficiency the colder the ambient temperature is, so if you live in the arctic circle this might not be the technology for you.
db2@sopuli.xyz 11 months ago
Can confirm, I hooked up an electric on demand for the time it takes for a single shower, it was stupidly expensive. It used way more power than a tank would to deliver hot water in a weeks time (math is fun). I boxed that pos back up and plan to sell it.
phoneymouse@lemmy.world 11 months ago
Heat pumps lose efficiency far above arctic temperatures. Below 40F, the efficiency drops quickly.