[kwyjibo]

So, how are you going to do it? If you are going to separate the hydrogen from the oxygen in molecules of water, you're going to have to use a lot of energy. Unless you're using solar or nuclear power, you're likely going to be burning fossil fuels to get the required energy. Even electricity is generated by burning fossil fuels at most power plants. Plus, I believe I've read that more energy would be needed to generate pure hydrogen from water than would be output from a hydrogen fuel cell.

The benefit of using hydrogen fuel cells is not that net air pollution is reduced. Rather, it's that the pollutants are redistributed from densely populated areas to sparsely populated areas. Which is not necessarily a bad thing, but it's being overlooked.

Maybe someday we'll be able to generate an abundant supply of hydrogen with no pollution. But that's still many years away.

[TommyDale]

"Maybe someday we'll be able to generate an abundant supply of hydrogen with no pollution. But that's still many years away."

I think that is the whole point of spending billions -- to FIND alternative methods, not just to convert automobiles.