I think petrol prices are to expensive, but I cant understand if all the big oil companies make billions of pounds a year, surely they could work with car companies to get a hydrogen distribution system. We could then use fuel cells.
why would they want to spend money on that when if they do nothing they can make even more
thats an awfully naive statement
They could still make a load of money on Hydrogen and then still save the world, everyone wins.
Of course I have no figures to back this up, its my own opinion, but I doubt itd take all the oil companies profits to invent a hydrogen distribution network.
Hydrogen is hugely inefficient to produce. Takes massive amounts of electricity to generate enough from sea water, and I am pretty sure they more commonly use another method that generates toxic or corrosive by-products, at least I remember reading something about that anyway 
But surely there are scientists and companies around the world that are developing new ways to produce hydrogen... Where a big cash injection say from Shell could bring their research forward a great deal.
See if Shell, for example, came up with the idea, to produce hydrogen and they got it all patented up, then they could make even more money by licensing it to BP.
