There is an interesting development going on to electrify some of the UK rail lines - an OverHead Line (OHL) - battery hybrid system.
The idea is that you have a standard electrified OHL system where it is easy and cheap (!!!) to install. Places whee you can't put it easily, such as under bridges, through tunnels etc, you don't. You have some (small-ish) battery capability in the train which recharges from the OHL system, and use that in the areas where the OHL hasn't been installed.
The idea is that you have a standard electrified OHL system where it is easy and cheap (!!!) to install. Places whee you can't put it easily, such as under bridges, through tunnels etc, you don't. You have some (small-ish) battery capability in the train which recharges from the OHL system, and use that in the areas where the OHL hasn't been installed.