Air source heat pump vs. solar thermal

Hello and Happy New Year to all BC peeps!

In late 2020 we got a quote under the Green Homes Grant to obtain solar thermal water heating for our property. However, the local company which would be installing have suggested that an air-source heat pump would be much more efficient.

My first reaction was to say that we thought solar thermal would be a safer option, as we’d heard air-source systems can be noisy. I also think this might just be the company attempting to get more profit. I’m sure it says that within the ‘eco resource’ on BC that noise might be a problem, but has anyone got experience to advise if this is a real issue?

Depending on Covid, our plan is to do major kitchen and spare room renovations finishing late-Autumn. If we have the funding for air-source heating and it will be more efficient and better all-round, we could try to fit it in within a 2-3 week slot.

Can anyone let me know their experience of work duration, intrusiveness and if it would matter that a couple of DIY fanatics are laying floors and units at a time when the thermal is being installed?


Hey Stuart. The Return on Investment for Solar Thermal is around 15-20 years, due to the energy saving potential. Air Source Heat pumps (ASHP) work to 300% efficiency, giving much greater energy saving potential, and return on Investment of 7-9 years.

However, the upfront cost comparison is significant. The Green Homes Grant would financially benefit the Solar Thermal more than the ASHP in the short term. However over 10 yrs the ASHP would definitely win out.

That’s all from me!

My understanding of the finance & efficiency issue is pretty much the same as Tom’s. I haven’t been through the experience yet, so all I can tell you is that I’ve been promised that installing a Air Source pump and new radiators will only take 2 days and they will “work around” me and my furniture. I will be having a Grant which has a decibel rating of 60-65.2 which is around “normal conversation/laughter”. I guess that might still be quite trying for the neighbours in the middle of the night. :pensive:

Hi Tom

That return on investment is very important. I think with the GHG paying a lump sum towards the installation, then we might be looking at a much shorter period for the ASHP paying for itself. This is a big positive!

However, the noise is still my big reservation. I think the best action will be to contact the installers - they stated they have a ASHP on their site, and we could listen to it in real time and see what we think.

Thanks Tom and Libby for your advices!