China is pushing so much power production via renewables that the idea of 'free' power is becoming more and more of a reality. I don't think using this for fuel makes a lot of sense but we use oil for a lot of things other than fuels. With enough investment in renewables to create huge amounts of excess power we can potentially use this to replace a lot of the non fuel uses of oil. Factories in the desert that produce their own raw materials from the air using the solar and wind right next to them is the dream here.