This article looks like a fine discussion about the economics of hydrogen production, but unless I've missed something it skips over the immense storage difficu

This article looks like a fine discussion about the economics of hydrogen production, but unless I've missed something it skips over the immense storage difficulty. Hydrogen is a difficult thing to manage in quantity. Its density is fantastically low, so storing it in gas form requires absurd pressures -- an inherent risk to any vehicle. Storing it in liquid form goes a long way towards solving the density/pressure problem, but now the system must have a full cryogenic process to keep the hydrogen liquified. (Worse yet: over time hydrogen embrittles (https://en.wikipedia.org/wiki/Hydrogen_embrittlement https://en.wikipedia.org/wiki/Hydrogen_embrittlement) metals, making storage even more complicated) This isn't much different than the problems faced by rockets, and it's why liquid hydrogen is not considered a 'storable propellant' for long-duration flight. In a zero-net-carbon economy, residual demand for high power density may still have to be filled by some kind of bio-derived or synthetic hydrocarbon.