Effort underway to suspend California's global-warming law

[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

[twobjshelbys]

Originally Posted by 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

A simplification of the process true. The bottom line is that energy can neither be created nor destroyed) and that the creation of hydrogen for fuel will consume more energy than it produces. The source of the consumed energy is most likely electricity. So you have to account for a huge electricity generation infrastructure that is probably as big as the one we currently have (whose only possible source is nuclear).

People envision cars that convert "air and water" to hydrogen on the fly. Ain't gonna happen...

The creation of energy is a nasty business. It took a lot of energy to create the crude oil (which had huge losses in the process). What makes it all tidy is we weren't around to see it happen.