Wind isn't the only renewable energy out there!!!
These data centres don't actually connect to the main grid, they build their own substations and give excess power back to the grid.
They also need their own Uninterupted Power Supply to keep the centres up and running incase of a blackout as 24/7/365 power cannot be guaranteed to anybody or company. The government might be able to guarantee a fixed rate for power but that would have to be looked at every year (im sure a contract states that) and im sure all the other companies could look for that too, not just Apple