this post was submitted on 11 Feb 2024
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At least with the locomotive example, you could make it fully electric and hook it up to the grid vs trying to haul around the electricity itself. Would require a good amount of retrofitting to work with existing rail lines, but would be a hell of a lot easier than alternatives to get ICE out of railway power.
For a freight train you absolutely couldn’t. Even high power lines aren’t powerful enough to power the electric motors on a locomotive through the standard way that things like light rails operate.
That locomotive example I used has a 4.5MW electric motor output. It would be next to impossible to get 4.5MW from the line to the motor using a third rail or something. The power draw would be too great for a freight train with say 6 locomotives. I live 50 feet from a rail line and 6 locomotives is about the average I see per train.
And just for scale, there are over 26,000 Class I locomotives like that in service. If each one ran for only 12 hours per day on average, that would eat up half a trillion kWh of power per year. That would be 12% of the total US electricity production per year, assuming no losses in transmission or efficiency.
You certainly can run freight trains off of electrified tracks. E.g. the iron ore trains in Scandinavia, which go up to 8500 tons, using a pair of locomotives that together output 10 MW https://sv.wikipedia.org/wiki/Malmbanan https://en.wikipedia.org/wiki/Iore
The US is running longer and longer trains as you have observed (up to a max of 14,000 tons), but that is only because they keep fucking over their staff so they quit, so they have to do that out of necessity due to a lack of drivers. It's far more dangerous as it increases the risk of derailment, it means the trains can't fit in sidings (which screws over scheduling as trains can't pass each other) and ought to be stopped.
Most modern electric locos and EMUs are 6 MW and up on European 15 or 25 kV AC systems. 8-9 MW is very typical for higher end locos and the BR412 EMU in its longest configuration (for an example of the maximum I can think of) can pull 11.55 MW temporarily, and all of that is from one pantograph. Doing cargo with electric locos is only impossible in NA because... well, because you can't, because there is no elecrification. Every single corner to has been cut to save every imaginable cost. It's not like you could try and see what's better, you literally only have old-school diesel tech.