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I live in the UK. Last September, I bought an air-to-air source heat pump for environmental reasons, to reduce our use of gas for central heating. I did the ca
by RobinL 5y ago
I live in the UK. Last September, I bought an air-to-air source heat pump for environmental reasons, to reduce our use of gas for central heating. I did the calculations and knew when we bought it it wouldn't save much money (you get a 3-4x efficiency improvement, but electricity is 3-4x the cost of gas, at least at September's prices).
Our main family room/kitchen is the largest room downstairs, and the only one we heat during the day in the winter. So rather than figure out the complexity and additional cost of an air-to-water, it seemed logical to dip our toes in with something simple.
It's been great. Our gas usage is less than half what it was the previous year. The room heats up faster in the mornings, so there's no need to have the heat on before we come downstairs. On cold days this winter, we were heating the whole downstairs for about 15kwh/day, meaning we're getting roughly a 3-4x COP real-world (closer to 4 i think, but have no way of precisely measuring). If I'm feeling chilly, I can sit directly under it in a nice warm breeze.
It cost £2,275 installed. The model was the Daikin-FTXP60M.
(Recognise that this does not necessarily undermine the argument in the video. But I do find it odd air-to-air source heat pumps are not considered more often in the UK)
Also interesting to compare this relatively modest investment with an electric car. Very roughly, the carbon savings we're seeing are comparable to the savings from replacing 10k miles per annum in an ICE with an electric (I think, rough back-of-the envelope calculation!).
- AitchEmArsey 5y ago> I do find it odd air-to-air source heat pumps are not considered more often in the UK Could be due to housing density and the reputation for noise, though I'm not sure how well-deserved that really is. Mostly I just think it is a mismatch between the age of housing stock (and the pre-existing heating solutions) with incentives. If I were building a new house I wouldn't bother with a gas supply and would use a ground-source heat pump combined with underfloor heating - but retrofitting that to my 150 year old house is never going to be cost effective versus a boiler. For residential developments, the government should just mandate no new domestic gas supplies and be done with it.
- dageshi 5y agoI believe it has mandated that from 2025.
- hedora 5y agoUnderfloor heating has an 8 hour turn on/off lag time. It's nearly useless out here in the SF Bay area, since we go from short sleeve to jacket weather every day, almost year round. Our air source heat pump is much quieter than old air conditioners. For efficiency, it has a giant, slow, variable speed fan. It's usually not running anywhere near full speed, and is still quiet when it does. Similarly, the blowers in the ducts are variable speed.