[bobthepanda]

Usually, the issue with this kind of thing is that

* this is a form of energy transmission that requires labor for the actual transport (the train crew) and so is automatically much more expensive and difficult than a dumb pipeline or power line which requires much less staffing

* it's hard to create energy storage that isn't also a bomb in the wrong conditions, and train tracks pass through populated areas. Fuel already has restrictions on where it can be routed because there have been fuel train explosions.