Tootfinder

"Terrence and Lesley Bridges have seen their energy bills drop dramatically, from £375 a month down to as low as £40, since they swapped their gas boiler for a HeatHub – a small data centre containing more than 500 computers."
https://www.bbc.com/news/articles/c0rpy7en

'I heat my Essex home with a data centre in the shed'
"It's fantastic because it's eco-friendly...We're not burning any gases," says Terrence Bridges.