What happens when the wind isn't blowing and you've invested heavily in bird cuisinarts?

You desperately hope it's in summer.

The weather can be fickle and the government has to make sure that there is enough back up generation for times when the wind isn’t blowing. Greg Clark, secretary of state for business energy and industrial strategy announced Monday that the U.K. will take the next step toward agreeing to help Hitachi Ltd. finance a new nuclear reactor.
So, people are paying extra for 'green' energy(when it's actually being produced), AND they're going to be paying for the backup systems.  Which aren't really backup.