Basically, I want the aesthetics of "EPS conduits" without the soft-sci-fi handwaving of actual Star-Trekian EPS conduits. Is there some system for distributing large amounts of power around a spaceship from a central reactor that isn't "big honkin' electical cables" and which actually makes sense when electrical technology is also available?
There are a few real-world examples of something similar that I know of, but they're not quite all the way there:
- Hydronic heating. We transfer heat through buildings from a central boiler by pumping steam directly into room radiators. But, that seems to be very limited in application. Could you do more than just heating rooms with steam pipes?
- Compressed air. Lots of tools run on compressed air, and for some applications the pneumatic versions can be simpler than electromechanical equivalents. But how many watts can you actually transfer that way?
- Power-over-fiber is a thing, transmitting energy as light rather than electricity, but I don't what the practical power limits for that are. Efficiency isn't bad--if you used fiber optics to trasnmit infrared radiation directly from a hot reactor to devices with photovoltaic cells, you can get over 60% thermal efficiency, which is comparable to electromechanical turbines.
- Plenty of home appliances still run on propane / natural gas--power delivered through a pipe!--because it is still easier to deliver large wattages that way than via electrical connections. This isn't particularly relevant to a spaceship, because you won't be manufacturing chemical fuel in your engine, but...
- Some designs for nuclear-powered rockets involve using lithium or sodium vapor to transfer heat from the reactor core to the reaction-mass heat exchanger, rather than passing reaction mass directly through the reactor. This is probably the closest analog to Star Trek's "plasma conduits" transporting energy from the reactor core to the engine nacelles, and then supplying excess energy to the "Electro-Plasma System grid". But is pumping lithium vapor around a ship actually useful for anything other than supply thermal thrusters?