I was thinking of storing the hydrogen outside the house like a propane tank. If there's a leak it floats harmlessly up because it's least dense gas. Though the one in Australia stores hydrogen as a solid.
If I were ever even considering storing something like hydrogen on site, it’d be in an underground tank. Last thing you want is a risk that something ignites it and you have an explosion with tank shrapnel sailing through the yard. Battery storage is safer (not perfectly safe, but safer) and works great in the event of a power outage if you’re in an area with unreliable service. If not, there’s no need for storage. The grid itself becomes a form of storage.
That hydrogen will need a generator burning it and a system to feed it. Between that and the hydrolizer, there’s a lot of expensive and complicated components that can break. And I’m not sure what that’s really buying you. For the grid at large, nuclear power for base load makes the most sense and enables us to use whatever power we actually need rather than having to turn off every light bulb that isn’t absolutely necessary.