Hydrogen vehicles are the "car of the future," and probably always will be. There are two types of hydrogen cars. Hydrogen fuel cell vehicles (FCVs) are EVs, but instead of getting their electricity from batteries charged from the grid, they get their power from fuel cells using hydrogen as the energy carrier. The tricky question is, where does the hydrogen come from?
FCVs use four times as much electricity on a per-mile basis as a battery EV if the hydrogen is obtained through the process called electrolysis. So, you would need four times the number of solar panels to go the same distance as you would in a battery EV.FCVs are 40% less efficient than battery EVs if the hydrogen is obtained through reformation of hydrocarbon fuels (mainly from natural gas), and this process releases significant quantities of CO2 into the atmosphere. FCVs have many difficult and expensive engineering challenges to solve before they will ever be widely available, and even then, the energy required per mile will probably still be substantially higher than for battery EVs.
Alternatively, internal combustion engines (ICEs) can be made to burn hydrogen instead of gasoline. Even these fairly simple conversions are expensive, and the energy required is, again, much higher per mile than with EVs. In addition, ICE hydrogen-burning (H2) cars still have some emissions and cannot be considered zero-emission vehicles.
And then there's the question of infrastructure for refueling. The electrical grid already exists for plug-in vehicles, but building a hydrogen refueling network would cost billions of dollars, assuming that safety problems with transporting and storing hydrogen can be solved..
The bottom line is that there is no advantage to using FCVs or H2 ICE technologies over battery EVs. See Joseph Romm's excellent book The Hype About Hydrogen: Fact and Fiction in the Race to Save the Climate. Read more: Lisa Zyga - Physorg.com | Ulf Bossel - European Union Fuel Cell Forum