Storage is the problem for PV, and hydrogen is just another form of storage.
To mitigate that, either spend a heap of money on storage, or simply put PV panels on top of things which can consume the energy generated, when it is generated.
The other thing required is scale. Small scale PV on a residential roof is an inefficient use of capital. You spend 10K and get 4K worth of panels - and that is if you are smart and lucky and that's without any storage.
So don't bother with a small train station roof. Instead look for the right roof space.
Industrial/factory buildings and EV's are two places which fit this criteria.
Factories, and their on-site warehouses, because they have enormous, relatively flat roof areas, and they consume a lot of power during the day.
EV's, because they are mass produced and they have storage built in already so don't need to consume it immediately.