[bomelia]

We don't have hydrogen cars because of two main problems. One, hydrogen does not exist in nature as a singular product. Its mostly hooked up to oxygen (water) and lots of carbon (hydrocarbons). Releasing it is expensive and at the highest efficiencies means it is a good battery or energy storage material (the energy balance in electrolysis and combustion is conserved minus inefficiencies).

Energy density is low unless very high pressures are used (making it dangerous) and at those pressures, container permeabilities are an enormous problem making container weight an even bigger problem. I am not sure I would be comfortable riding around in a vehicle with a 12,000 psi container of hydrogen under me!

But when these and other problems are solved, maybe someone can figure out how to exceed advanced batter energy densities (and do so at lower weights) and make hydrogen fuel cells the battery of the future. Really, in electric vehicles is how hydrogen will be used (not combustion engines).

Mike