newshound wrote:
We don't use gas fridges because we don't (yet) have mini gas turbines
to drive the compressor. The old fashioned gas fridges were the
"absorption" type, much less efficient than modern ones.

And the primary advantage of electric heat pumps is you can run them off
renewables, which you couldn't do with a gas heat pump.

When the CEGB was privatised, one of the managers was going to use his
redundancy payout to try to adapt lorry turbocharger technology to make
a "home" system to generate domestic electricity and use the waste heat
for DHW and central heating. I helped him to scrounge some laboratory
C&I stuff that was otherwise going into a skip for him to start making
prototypes. I guess it never got anywhere, but I was always slightly
sorry about that. It seemed to me to be a scheme with potential
(although probably better in colder climates with a more consistent CH
requirement).

'Combined Heat and Power' is a thing you can buy today:
https://www.thegreenage.co.uk/tech/chp-boilers/

The problem is generally modulating down - they really want to be run full
blast, but that generates too much heat for a domestic setting. Even in
cold climates, you would be much better off insulating. They might be fine
for something like a swimming pool where there's a constant predictable
heat demand.

Theo