We have reached the end of our first heating year with our heat pump and the results are in. We got the keys to our house in October 2024 but were doing renovations so didn't actually move in until the start of January so it isn't 100% comparable as the gas heating wouldn't have been on as much before then.
We had a 14kW Daikin HP installed in May and solar and battery installed in October. The figures below don't include the fact that we are now disconnected from the gas grid saving the standing charge too but I'm reasonably happy. The consumption figures come from a Shelly power monitor. We paid about the same year on year overall however the house is massively more comfortable. The COP isn't amazing, it was 3.4 for just the heating. We clearly have work to do better insulating the house, cutting out draughts etc.
I am really happy with the solar system though. It isn't shown here but between bill credits, self usage and export we have saved £1,500 in about 6 months. Over the winter it brought our cost per kWh down to £0.19 for imports plus we exported a reasonable amount. Without the solar the heatpump would have been definitely more expensive than gas though I'd still say it would be worth it for the added comfort it brings.