And a related question is whether there are more interesting/efficient things you could do with that energy. It's a question that relates to the laws of thermo

And a related question is whether there are more interesting/efficient things you could do with that energy. It's a question that relates to the laws of thermodynamics as well which dictate that the conversion between different forms of energy has some theoretical upper limits in terms of efficiencies and those inefficiencies multiply if you have a series of such conversions of e.g. solar power to carbo hydrates to mechanical energy or electrical energy. The longer that chain, the worse it gets. You are better off charging a battery and using the stored energy directly. Almost no losses that way. It's the most efficient way to use energy for a lot of things. There is a market for synthetic fuels of course but it is going to have to be a market that is willing to pay at least 3-5x the energy cost they would have if they were able to use electricity directly. A good example is long haul aviation. Batteries don't work for that (too heavy). Shipping might be another one.