Really? Never seen such devices, at least in US. Pretty cool.

So the OP is correct for anyone lacking a heat pump? Heck, I know nobody around here who uses a heat pump. They just either burn gas or simply uses electricity to heat a water system that goes through radiators around the house/flat. So your answer shouldn't be a yes, but a ''yes in the case of having a modern heat pump''?

@AndreiZ., they are very popular in the US and have been so for the last 10 years.

@AccidentalBismuthTransform, what part of the US do you live in?

They are pretty popular in the UK (and most of Western Europe), and about to get a LOT more popular if and when the government bans the sale of new gas boilers.

Of course, resistive heaters are much cheaper to build and maintain. A good chunk of new houses being built where I'm from do use heat pumps, but they weren't particularly cost-effective (the underground kind), despite their very high efficiency. This changed rather dramatically with the massive energy price increases recently, and it's unlikely that trend will change anytime soon. In any case, heat pumps are pretty ingenious :)

@AndreiZ. You may not necessarily know it as a heat pump, but an air conditioner working in heating mode. At least where I'm from, reversible air conditioners are the norm (not everyone has AC, but everyone who has AC has reversible AC).

@AccidentalBismuthTransform OP said assume location close to the arctic circle (so that heating is always needed, which isn't really true btw). In such locations, direct electric heating is uncommon, because it is inefficient and therefore expensive. Direct electric heating may be more common in other areas where there is less need for heating and the difference in cost is negligible.

@AccidentalBismuthTransform: The other thing to consider is that different forms of heating cost different amounts - if you have more efficient lighting, it may be true that the (say) 1kW you save has to be replaced by 1kW of heating. But if you pay less (per kWh) for your gas than for your electricity, that's still a net financial saving :)

Heat Pumps are a Scam! That would violate second law of thermodynamics!!! You only can get energy from outside if outside is hotter than inside. But in that case just opening the window is enough!

@nadapez Care to explain how a fridge works? Or are fridges a scam too?

@nadapez you need to rethink your logic here. Read up on heat pumps and then come back and comment.

Ok. I hadnt thought that well. If you pump energy from outside you get that energy plus the energy you waste in the process converted to heat. Thats a gain

@aucuparia Not sure what you mean by "most of Western Europe". I rented or visited dozens of flats in France, Belgium and Luxembourg over the last 15 years, and none of them had heat pumps. I've only seen them in some hotels and there are some acquittances in Germany who have one in their house, but that house is worth over half a million so those are by no means "average Joes".

@DmitryGrigoryev But did those flats have direct electric heating instead? Because that's the only case where OP's argument makes sense.

Here in the Seattle area heat pumps are perfect. The temperatures are mild and we I have lots of Hydro energy.

@jkej A few of them had electric heating, the wast majority used gas. But it's not an argument directed to the OP, it's a reply to the claim that heat pumps are "pretty popular".

With one caveat, heat pumps (the atmospheric one, not the in-ground ones) don't work in very cold weather. The OP mentioned the arctic circle. They may exist, but I don't know of any heat pump that will work at -40 (C or F:))

@DmitryGrigoryev they're getting more common. Anecdote: CERN shuts down over winter partly because electricity prices are significantly higher then, but they've also noticed an increasing spike in mid-summer due to increased use of air conditioning (heard from someone who works on CERN's electricity distribution). One Geneva summer I was there in a non-air conditioned house when it hit 40C, so it's understandable

NE U.S, here, and in my whole life I've never heard of heat pumps or reverse AC until this post. "Heat pumps continue to meet only a small share of residential heat demand (around 5% in 2019)..." IEA Report.

If you have a ground or water source heat pump, or live somewhere with mild enough winters that an air-source heat pump can function, then yes. If you live in a really cold climate and the only alternative is resistive electric heating, then no.

Note also that burning gas to generate heat is more efficient than burning gas to generate heat to generate electricity to generate heat. This is where it gets complicated, because if you can't use a heat pump (which is strictly better than resistive heating), you would need to compare the impact of an alternate means of heating. OTOH, the OP is correct that resistive heating is resistive heating, whether it comes from something intended for that purpose, or is a byproduct of lighting. (TC has some good videos on the subject.)

@Dmitry Grigoryev: Flats (apartments to US English speakers) are not houses. They will often have a shared heating system, so 1) you might not know what kind of system it is; 2) the builder probably put in whatever was cheapest when the building was built, not being concerned with ongoing costs; and 3) Many apartment buildings, especially in Europe, were built long before heat pumps were available.

Meh. It's actually not more efficient if your electrical power comes from burning hydrocarbons, which it usually does in environments that need 24/7/365 heat.

@AccidentalBismuthTransform you have lots  of rep. any chance you could edit the answer to include that little bit about 'if you do not have a heat pump then efficient light bulbs are not needed. If you do have a heat pump then you should buy efficient light bulbs.'

@jamesqf I can't speak for the rest of Europe, but in France, heating via heat pumps is absolutely marginal, even for new houses. It's either electrical or by gas.

See also: nrel.gov/news/features/2021/…

Flats in some European countries are often heated by district heating systems. No electricity, gas, or heat pumps needed. I believe this is still uncommon in North America.

I feel it should be pointed out for this thread that ALL ACs are heat pumps, they use the heat pump/refrigeration cycle to move heat from one side of the system to the other generally with an efficiency of around 5w moved per w spent. Some heat pumps are reversible through the use of literally a single extra switch. the efficiency of an ac pumping heat into a house is generally 5/1 as long as the outside radiator doesn't start freezing.