Because free hydrogen does not exist on earth, it is not a fuel source, it is an energy transport mechanism (much like gasoline). Gasoline comes from crude oil making crude oil the actual energy source. Where does the hydrogen come from? Despite the dreams, it does not come from water. Pulling hydrogen away from the oxygen it is bonded to in water is very expensive. To do it in a commercial venture takes huge amounts of electricity (another energy transport mechanism). Most commercial hydrogen in the US starts out as natural gas. It is far cheaper and more energy efficient just to burn the natural gas in the bus to begin with.

Which brings us to hydrogen’s supposed great advantage, lower emissions. Keep in mind that in this case we are not comparing a hydrogen bus to a gasoline bus, we are comparing it to a natural gas bus. Natural gas busses are already regarded as burning extremely clean. Clean enough that most larger airports already use them over gasoline or diesel power in shuttles. The hydrogen bus will have lower carbon emissions (not zero, it still has some burn off of lubricants), but it will have much higher NOx emissions. That is because hydrogen burns much hotter than natural gas does. Higher combustion temps create more bonding of nitrogen and oxygen. If you factor in all the carbon released when the hydrogen was originally pulled out of it’s source natural gas, there is a good chance that the hydrogen bus pollutes much more than the natural gas bus does.

Much as I love the dream, nothing comes for free.

I have no idea whether they can be commercial, but the idea of not supporting the oil-producing nations sounds good. But Ford?…