Also ... renewables are always going through cycles of high and low availability. Prices vary across these cycles. If you make your fuel only at the time during the day when there is the highest delta between supply and demand, then you pay the minimum electricity cost, and the utilities are glad to have you there to balance the load.
Note that this economic strategy is already in place in other industries where electricity price is a large component of the final cost of goods sold. Aluminum smelting is a huge example of this.
