For the home user, it would probably be easier to sell excess capacity back into the grid (assuming your local utility is willing to take it). Where I live, we experience frequent power outages in the winter due to high winds and snowfalls. Storage would be a nice backup option. If hard pressed utilities become less reliable, that would also increase demand. And the suggestion of variable power rates might also help. Simply a matter of energy costs vs storage costs. They will meet at some point no doubt.
I also like the idea of the compressed air option, but I wonder if it is too inefficient.