If we could bring the discussion back to the terrestial plane....
Yes, electrolysis is inefficient, but that doesn't mean it's no good. Consider that solar is probalby the most promising "new" source of power. It's relatively cheap, very clean, totally renewable and "almost there" technologically. The big drawback to solar is storage. Hydrogen is one of several solutions being considered. None are close to 100 % efficient, and (as somebody pointed out) it's physically impossible to devise a fully efficient storage system. However, a 50 or 60 % efficient system would be a lot better than what we've got now. I mean, isn't 50 % of something better than 100 % of nothing?
This endless quibbling about the so-called drawbacks of alternative energy is anything but productive. I guarantee, in a very short time a 50 % efficient system is going to look very attractive.