Hi, I'm working on a fiction project set in a rebuilding society 100 years out. It's fairly utopian so people are prioritizing restoring and improving train infrastructure and service pretty significantly. American cities have high speed rail connecting them, and because I'm building this story out of my daydreams, defunct short lines have been returned to service and even rural towns have some kind of passenger train running again.
The opening has the players traveling way out into the boonies, and part of setting up that 'traveling off the edge of the world' feel was having them leave whatever city they begin in by HSR, then take successively cruder public transit until the line just ends short of their destination and they have to figure the rest out on their own.
The second-to-last step in that chain is an electric self-propelled railcar traveling along a restored short line. I think the current doodlebug is a somewhat-recent thing, put together maybe within the last ten years, and probably planned to be temporary when they built it.
So my question now is: how would they build this thing? Would it be easier to convert an existing self-propelled railcar like the Budd RDC? Would it make more sense to start with a regular coach and retrofit in the batteries, motors, control station, pantographs etc?
Or would it make more sense to start from scratch? Maybe use part of an electric bus or similar?
Reuse and salvage play a pretty big role in the story, so I'll probably embellish any option with details about where the parts came from originally.
Thank you for any advice!
Battery electric trains can resolve a lot of the technical conflicts, since a battery averages out power demanded from the electric network. But then you need to figure out the logistics of where trains would charge (eg layover in some towns with good electricity connections) and what the battery capacities might be for your story. If we say batteries are now 10x more efficient in 100 years, then that basically solves most of the difficulties.
But we don't even need the batteries on the train. With such efficient battery technology, it would be entirely feasible to connect to a neighborhood distribution circuit, with a track-side battery that slow-charges from the grid. Then when the train whizzes by, the track-side battery dumps power onto the overhead line, which powers the train.
This latter idea is entirely feasible today but the sheer number of batteries is what makes it impractical or financially impossible. Hence why if batteries became 10x more efficient, then the idea can be implemented.
Phrased another way, to build a trackside battery in 2025 would likely take a lot of skilled engineers to build a structure about the size of one or two houses, then fill it with batteries that hopefully don't explode or catch fire. But in 100 years, the advanced battery tech for a trackside battery could conceivably fit the same capacity into the space of one of those roadside green utility boxes. And that would be a lot easier to install in a fictional future where the country is rebuilding at a grass-roots level, when large-scale coordinated engineering might not be possible.
This is an awesome explanation and I think it feels like a good way forward! I'll read up on bus power draw to make sure but I think we're approaching reasonable - especially if the towns are already setting up battery banks to manage their own power demand.
Thank you again for all your help, I really appreciate it.