Re: Go Japan Go
You may hope, but where will the energy come from for electrolysis of water to hydrogen & oxygen?
If we consider each country's energy trade balance then I start to see a problem. Exclude fossil fuels, and who has now, or might realistically have a surplus of energy of any kind? Even in countries with high levels of wind resource (eg the UK) these still contribute fractional levels to domestic energy needs, so the chances of wind producing (net) exportable power are small. The only other scaleable renewable energy is not homogenously distributed, so if solar energy is used then the energy powers will be the desert belts of the globe (because they not only have the best solar resource, but also vast areas of land with no alternative uses). So in your H2 world the likely energy powers are the countries of the Middle East and North Africa. And who will pay for the capital intensive solar capture, electrolysis, storage and transport of H2? In part the existing oil-based sovereign wealth funds, in part the banks. Who has the expertise in managing energy transport, shipping, distributing and marketing chemical fuels?
Oh, dear, sounds like we're back in the very same place you don't want to be - raw energy in the hands of the Arabs, the usual crooks in charge of the money, Exxon, BP et al doing the operations and marketing. And as icing on your cake, at any global scale, of course, saturating deserts with sufficient solar collectors to fuel the energy needs of the fast growing developing nations and the import dependent developed countries will significantly alter the albedo of these regions, and contribute to a rather clearer form of AGW, although I suspect the hippies will ignore this.
There is an alternative, and that's nuclear. Lots, and lots of nuclear. For the UK, even if we cut total energy demand by 50%, we'd still need to build six times as many nuclear power stations as we currently have to support an H2 economy - something of the order of 90 reactors. On a global scale we'd need to use either (or both) fast breeder reactors or thorium to make sure there's enough nuclear fuel to go around, and the total system costs would be astronomical.