Well, it might be greener in the immediate vicinity of your car, but it would produce more CO2 stripping hydrogen from water than it would if you just burned the coal directly.
Basically, you would burn coal to produce the hydrogen, which you would then burn in turn, to revert to water.
The First Law of Thermodynamics says that you can't get more energy out of a process than you put in. And the Second Law of Thermodynamics says you will get less energy out than you put in.
Ergo, more energy will be used, and more CO2 produced, because the two step process will inevitably be less energy efficient.
Thank goodness for the Second Amendment. No reason.
I see no problem burning lot and lots of coal. The real problem is not CO2 but smog and suffer output.
What the have come up with is a way to make it easy to have a plant with no real smoke stack.
Yes there is a cost but it does solve one problem air borne emissions. They will have to look closely at what all that CO2 will to the ground water too.
Global warming may or may not be something to worry about but smog in the cities is. If any number of electric cars are ever going to be used the need for power plants that are mostly clean will have to be met.
Right now we can't build any thing except peaker plants which run on natural gas which should be used as a car fuel not for electric power.
We could in ten years make every city in the country almost smog free buy using a little of all the options we have now.
1) For short trip use an electric car will be fine. The batteries will need to be made for recycling from the start. For a second car with less than 30 miles to and from work this would be fine for lots of people.
2) All heavy trucks that drive mainly in town need to be natural gas. It burns 80% cleaner than gasoline.
3) Hybrids should be electric cars with a super efficient generator to extend the range.
4) True lean burn engines are out there. I see no reason a full sized car can get 40 mpg city. The fed mandated catalytic converter must go. Right now if you lean out your engine then there is not enough un-burnt fuel to light up the converter so they have to add more fuel to the mix just to make it work. If you lean out your car you are breaking federal law!
A link to some lean burn ideas.
http://fuelvapors.com/best/main_pages/10_examples.htm
Water injection will reduce emissions by 20% to 30% or more and allow for even leaner mixtures.
I'm not green in any way but what we have been doing the last 15 years or so is not cutting in Phoenix any how. Vally of the smog.
"it would produce more CO2 stripping hydrogen from water than it would if you just burned the coal directly."
I believe what he said was that the carbon that is produced is easier to trap, not that there was less produced. Not certain what the technical reasons for that are.