Liquified is the only option, I think. Compressing it into cylinders or storing it as a metal hydride is probably way too much weight. Until recently, making h

Liquified is the only option, I think. Compressing it into cylinders or storing it as a metal hydride is probably way too much weight. Until recently, making hydrogen by electrolysis was not a benefit, environmentally, as a lot of the electricity would have come from fossil fuels. I think decomposition of methane is an option that would allow the carbon to be sequestered.