If you watch the video he points out why it works in those countries. They have learned to live in a cold country by building housing to suit. We have not done this because we burned cheap coal instead. All those older housing is not up to scratch. One thing you cannot get away from is the noise. We live with a much smaller land foot print than they do in Scandinavia. You are right about the oil though. I should have said fossil fuelled. I will edit it.

I am also speaking from experience. My sister took advantage of the scheme. They are very underwhelmed. I am never said there is no benefit. I think there are better gains in other areas.

My French relatives have some sort of ground source heat pump, having designed everything in their home to work on that basis, and it is everything you describe in terms of size - the pump unit is huge and impressively loud. It worked very well, when it worked. Unfortunately, the underground bit is also broken and the installers who broke it have refused to solve the problem. There is a fair amount of cowboy engineering going on in this domain, it turns out, a lack of reliable support for existing units/installs, and of course the usual attempts to extort money from people of a certain age. It makes me sick that they did everything right and were let down anyway. I'm not saying avoid this technology necessarily, but if you get a lemon and/or are unlucky and hire shysters there is practically no ceiling to the costs involved.

The cost of electricity in the UK has come down since the chaos, thankfully.
Numbers are a little up in the air at the moment, as governments are shielding people by varying amounts. So picking a good source was a little tricky.

This was the natural gas value I used (Dec 2022) (13p/KWh vs 10p KWH, expressed in GBP) And I used the data from here for electric. (June 2021) (17.3c/KWh vs 25.1c/KWh, expressed in USD)

France has a much larger nuclear fleet, and has generally had cheaper electric than the UK.

NG is about 40% of the price of electricity per KWh in the UK, vs 75% of the cost in france.

Similar thing with my Mum and Dad tbh. They moved to the west country and though the house has heating it's evidently been designed when it was built to be heated most efficiently by the wood burner, which probably used to be a normal fireplace. (It's not some isolated cottage, it's just on a street, just to clarify...)

Theres a radiator in the spare room when we stay for instance but it might as well not be there for all the heat it manages.

So I think they'd be in an identical situation to you, they'd have to do up the whole house before it would even be worth looking at. But since they get hot water and they don't freeze in winter they just stick with what they've got because they don't really want to pay messing around with the house.

We use radiators because every house had a gas line for heating, boiling water and cooking. Radiators were more efficient than gas fires.

Most residential gas boilers are 20-35kwh, air source heat pumps (£4k-£5k) are linked to compression cylinders which provided 11kwh of heating and cost of £9k each, with the need for a water tank, etc... and then installation cost.

Putting air conditioning in still requires the heat pump with a unit (£500-£1k) for each room, plus installation costs.

If you take a 3 bed room house, you are looking at ~£15k for an air source heat pump vs £9k to put air conditioning into every room (it gets worse for air sourced heat pumps the bigger the property).

Once you move to air conditioning for each room you don't need radiators. This means your hot water supply is dishwashers, washing machines, taps, baths and showers.

Dishwashers and washing machines boil their own water (for efficiency).

Taps and showers have electric solutions. The price difference between the two is so great you could buy a hot tub to replace your bath.

Air source heat pumps don't make sense