Hydrogen storage
Safely isnt really that much of an issue from a technology standard.
Engineers are already looking at converting wind power to hydrogen (it was via electrolysis) as a more efficient method of transferring energy from offshore to land as the %of electricity lost to power transmission can be upwards of 6% - even at very high voltages (where windfarms use step up transformers to send the power). This would open up large shallow areas of sea which are not close to land, but have more consistent wind - such as Dogger Bank and potentially floating (rather than anchored) wave and wind power. Tankers or pipelines then 'tap off' hydrogen and return it to land.
One of the problems with gaseous hydrogen is that to have decent quantities of it, it needs to be rather compressed..... and compressed Hydrogen is perhaps the molecule most prone to leaking through other materials - as well as making others brittle. Steel is one of the worst to get brittle damage - though copper pipes are almost immune, they cant handle sustained pressures and is fairly porus, so complex material engineering is going to be required....
Biting the hand that feeds IT
