What tantalizing to me is solar and wind are unique in that the marginal cost of production is near zero. Meaning very unlike coal and natural gas energy source

What tantalizing to me is solar and wind are unique in that the marginal cost of production is near zero. Meaning very unlike coal and natural gas energy sources. That leads to a energy grid characterized by frequent over supply. My thinking is electrowinning iron and mini-mills could easily absorb excess capacity. Aqueous electrolytic cells should be able to just sit idle for hours to days. And electric furnaces draw easily 10-100MW. That makes them a good match for a renewable grid.