Bitcoin mining farms will always look for the cheapest energy. If that is in a remote oil rig location where methane needs to be flared, or near a hydro power centre, or in a desert next to a bunch of solar panels. But yeah, if there is an excess of coalplant energy that will do as well.
I don’t really understand the hate ₿ gets for this. The existing alternatives (fiat currencies) are way more polluting, minus the dependable know inflation.