Even the H2 process is horribly inefficient. Just use the electricity directly and store the small amount that is needed for peak levelling in ordinary batteries.

All these ways of using hydrocarbons are less efficient than batteries and only make sense when the hydrocarbon has a higher energy density and when the density is actually needed.

Just install a battery in every new home, make all new homes comply with passivhus standards, put solar panels on top of all new commercial buildings, generally stop wasting energy. And strengthen the interconnects between countries so that places like Spain can sell excess solar to France and thence on to the rest of Europe.