Battery is expensive and doesn't hold much. Nobody buys your hydrogen or heat an it needs to be made, stored and transported with losses that make this endeavor uneconomical (that's why nobody is doing it).

So you have two options really. Either partially sponsor your windturbin with bitcoins you'll mine with it or not build the turbin at all.

The current problem is not how to utilize every bit of excess energy. The current problem is where to get the money from to build capacity that will at time generate excess that is hard to transport away from the power station.