Looking at them as a cheap and reliable miner already have some power supplies have buildings with wind and solar on them and the need for them to be heated. Little project of mine using some HVAC to spread the heat to other parts of the building i run an electrical contracting company that owns a few buildings. Might be a complete waste of time but wasted my money on worse things 
This is pretty smart! Good luck with your venture. Perhaps approach a large mining company like Genesis Mining and offer to purchase some of their old tech off of them. I'm sure you'd be able to get a decent rate for the - and they're based in the UK which is quids in for you!
Where in the UK are you based? Scotland?