Engineering considerations will trump enthusiasm. Taking into account engineering considerations like reliability, operating life, material properties in vari

Engineering considerations will trump enthusiasm. Taking into account engineering considerations like reliability, operating life, material properties in various environments, product quality, safety, known materials performance, operating life, and especially costs, capital and operating -- taking all those into account, the best uses for any electrolysed* hydrogen, made as a use of otherwise unused electricity, seem to be making fertilizer and hydrocarbons. The latter are very energy dense, super cheap, and safe to store for long periods and to transport long distances to where the stored energy is needed. Those two products are best made at isolated large scale dedicated plants operating continuous processes. It's not clear to me that hydrogen as hydrogen has any role as an energy storage or transport medium, nor is it clear that PV alone is a good fit as the energy source for the likely uses. * I'm guessing by hydrolysis you meant electrolysis to produce hydrogen? "Hydrolysis" means "chemical reaction occurring with the addition of water", e.g sucrose -> glucose and fructose.