Musk goes on to state that even given the very best hydrogen technology, it doesn’t come close to the energy density of a modern lithium-ion battery pack like that found in the Model S.

Granted, Musk is a bit biased and firmly entrenched in the battery electric vehicle space, but despite years of promises from automakers and government agencies, it’s tough not to think that the zero emissions future promised by hydrogen is still a long way off.