I'd actually be more interested in seeing how big of a part green energy is of those statistics...
I'd imagine it could be a lot cheaper to generate your own power with either solar or wind, especially for large-scale mining operations.

What's the problem with Bitcoin mining taking up so much power? Would this be an issue if the missing capacity was filled with additional renewable energy?

I really think that in some point in the future, we're really not going to be worrying about power anymore. Once we transition to highly efficient and environmentally-friendly renewables, power consumption might not even be an issue anymore. We're still pretty far off from that, but I do think we'll get there eventually. (If we don't destroy our planet first)