re: Whats wrong with a CH4 economy?
Well, nothing. We've got one already that uses CH4 and longer chain hydrocarbons. works quite nicely, IMHO.
If you're looking at something to generate CH4, there are easier (cheaper) ways to do it than this.
This process is of value if you want a centralised source of H2 which you distribut to end-users and have onl H2O production at the end-user site. The CO2 you capture and sequester at source. if you truly beleive that global warming is:-
Evil
Man-Made
And can be stopped by changing the basis of our energy economy
Then you need something like this.
If not, then you don't..