The extent to which adding any mining data center is "good", even assuming that Bitcoin is "good" is incredibly abstract. Yes, it may make that one miner more money, but it creates no new net economic value, its only value is making the blockchain more secure. Is it good to make the security of the blockchain dependent on electricity demand?
There are plenty of better ways to increase demand that are more useful than burning it for fungible security. For example you can build datacenters that can shift load by time and location based on the state of the power grid. Google and Facebook already do this. You can build battery plants which address the problem directly. Electric car charging should be incredibly complementary to demand response.
Posing Bitcoin as a solution to generation problems assumes that the biggest problem is finding ways to use energy, which is absolutely not the case. It's a solution in search of a problem.