2% seems too low to me, but I'd be surprised if it was much over 20%. Professional level bitcoin mining has been a thing for 5+ years now, and it's highly optim

2% seems too low to me, but I'd be surprised if it was much over 20%. Professional level bitcoin mining has been a thing for 5+ years now, and it's highly optimized for efficiency. Hydroelectric power is often where the best deals can be cut, so the industrial scale miners have tended in that direction.