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Comment by qwerty456127 | Hacker News Reader

How much do they pay? I've heard electricity is quite expensive in the UK so surviving a winter can be hard.

For the most part electricity isn't used for heating in the UK, generally gas central heating is preferred. There are obviously some exceptions, houses built in the 70s with electric ceiling heating (this is as bad is it sounds) or electric storage heaters.

Electric heating in a country like Scotland is simply unconscionable. There is natural gas infrastructure. And where it’s not, even oil is better than electricity.

Unconscionable is a strong word. Ground source heat pumps powered by renewablely generated electricity is pretty close to an ideal scenario. Resistance heating from electricity generated by gas is pretty bad though.

These days many new builds are using air source or ground source heat pumps. And existing dwellings are beginning to be retrofitted for them. I don't have numbers, but I expect that it will soon be the norm for new builds for places without gas infrastructure. Especially with any new legislation around heating for new builds (e.g. https://www.gov.scot/news/new-build-homes-to-be-more-energy-...).

A few people in this thread are talking about electric heating being awful. And yeah, I think traditional electric resistance heating is expensive and not very high quality, but modern electric heat pumps are one of the most efficient forms of space heating we have, they can be run in reverse to cool houses too, and they increase comfort a lot — many systems allow you to have room-by-room control of the temperature. Plus they're used everywhere in Asia already.

Here's an example of someone's experience installing and using a "mini-split" heat pump for their house: https://www.sustainablelafayette.org/single-post/home-electr...

Yeah heat pumps are the answer to places like Scotland. As a bonus you get air conditioning.

They do have some problems with extreme cold (not really an issue in Scotland or most of Europe for that matter) but even in such a case should still be used together with plain resistance heating. But that kind of cold has very few people living there anyway (think -30c or colder)

I've been wondering about this! I keep hearing that air-source heat pumps aren't great in pretty cold areas. Do you have any links or references on this? I live in the Northeast US and wanted to see what the options were and what people's experiences have been.

Basically the Coefficient of performance (COP or SCOP for seasonal version) just keeps going down with the temperature (under 1 means resistance heating is better)

https://en.wikipedia.org/wiki/Coefficient_of_performance

Models made for cold climate work to around -30c. Wikipedia has okish writeup about their functionality in cold climates

https://en.wikipedia.org/wiki/Air_source_heat_pump#In_cold_c...

Don't really have any good sources in English for this (most reading I have done on this is in Finnish)

For example here are some excerpts from a report done by VTT (the Finnish governments research center)

https://www.scanoffice.fi/vttn-testiraportit-ilmalampopumppu...

If you scroll down you can find some pics "lämpökerroin" is COP and "ulkoilman lämpötila" is outside temperature.

From that you can see that the combo of Mitsubishi Electric MSZ-LN25VGW + MUZ-LN25VGHZ still holds a COP of 2 at -30c. On the models not made for such climate/cheap ones you can see it drop to 1 (or below)

Ooh awesome thanks for the references!

My previous house has an air source heat pump. There was a thermometer outside and the furnace automatically switched from the heat pump to gas heat when the temperature was below 14f. (some heat pumps work to colder temperatures). I saved a lot of money over the cost of propane (which is more expensive than nat gas), and didn't really notice any problems.

Every third house has an air source heat pump where I live in Norway about 40 km south of Oslo. My next door neighbour has two. The produce more heat than the input electricity until the temperature falls to about -25 C.

They're expensive though, and basically unaffordable to retrofit an existing home, which would typically be already using a gas boiler.

Here is a comparison for European countries: https://ec.europa.eu/eurostat/statistics-explained/index.php...

I'm the UK. I pay 14.97p/kWh (which includes tax).

The average UK household uses about 3,800 kWh per year.

"surviving a winter"

Yeah many are just growing a layer of fat and hybernating. Hence the obecity rates

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