Photocatalyst splits water into H and O2 at quantum efficiency near 100%
As it stands, I don't see how hydrogen proponents in either vehicles or energy distribution can recoup the head start of pure electric. The best electrolysis + fuel cell cycles commercially available are maybe 35-40% efficient (electric-electric). Maybe someday, 20 years from now, some quantum catalyst gizmo will push that to 90%. For vehicles you then need another step of compression to force the hydrogen inside a very high pressure tank - by the laws of thermodynamics this can only cost you energy regardless of any technological advancement.Meanwhile, electric batteries today are over 90% eficient on the whole charge-delivery cycle, the industry is rapidly gaining momentum, charge networks are built, the cost of components only goes down. Compared to hydrogen, battery electrics are today where internal combustion cars were compared with electrics 100 years ago: the market has spoken and the massive economies of scale of the winner will relegate the competitor to very specialized niches.And once you lose the hydrogen vehicles, the whole distribution network becomes a very dubious business proposition. Why build H2 pipes that need expensive and inefficient electric conversion endpoints, when you can rely on and extend the existing electric distribution networks? Indeed, you can store hydrogen, but what advantage do you have by storing it closer to the consumption point, instead of a grid connected hydrogen battery that generates, stores and consumes hydrogen as requested by the smart grid? In that scenario, hydrogen becomes just one of multiple competing energy storage technologies, together with pumped storage, grid connected batteries etc., all together helping to regulate intermittent renewables.