FYI the purpose of the heat pump is not to mine coins but to heat your home and your water.
I'll give you a nice example of how this could come in handy from my own recent experience. My friend has a house in one country, but moved to another before the pandemic and had trouble coming back for winter, so he decided to stay at his girlfriend's place for a few months. I got a call from him a few days back to check on the house and it appears he had a flood because it got so cold in there the pipes froze and burst (the temperatures went down to -20 this winter which is pretty rare. Last winter we maybe had -5 outside tops and his house was fine). So if he had a mining rig in there he'd be able to get some coins for free and keep the house warm.