My sense was that this was only the case in countries that have effective environmental regulation, and that coal was cheaper in countries where you could legally operate super-dirty plants. Is this no longer the case?
It may turn out that there are other regulations (e.g. privacy regulations) preventing a company from gathering that information about individuals, though. At which point the power company would probably have to stop selling to individuals altogether (i.e. provide no residential power service any more, just private commercial/industrial service to other companies, because companies have a lot fewer privacy protections so it's easy enough to figure out whether they're mining.)
An even better scenario is if the government subsidizes the building of the hydro plant - then you get cheaper up front cost and cheaper recurring costs. This is the case in Austria, according to HydroMiner[0].