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Comment by zmgsabst | Hacker News Reader

This thread made me curious, so I looked up engine sizes between trains and boats.

A transport ship[1] can carry 9500 TEU with 53,000hp. That’s 190,000 feet of containers, or 36 miles.

A train can be 1.5 miles with 4000hp per engine. (According to Google “facts”.) That’s 24 trains to move the same containers, with at least 96,000hp between them. (And that’s ignoring a 1.5mi train will have more than a single engine.)

That trains use more horsepower to move the same freight suggests that they’re less efficient.

[1] https://en.m.wikipedia.org/wiki/COSCO_Guangzhou

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My Toyota Sequoia has close to twice the horsepower than my Cessna 182 did, but the Cessna burnt easily twice as much fuel per mile than the Toyota.

The Cessna cruised at 65% power. The Toyota cruises at closer to 10% power, but needs the excess power available when a hill comes along.

I suspect a similar dynamic exists with trains and ships - trains need to have power available to go up a hill, while ships probably cruise at closer to full power.

Thanks. To dogpile on what a bad measure that was, I'd add another example:

A Tesla Plaid S is 1020HP.

Is it less efficient because the engine is oversized? Seemingly the opposite. It's 33kWh/mi compared to the nearby Performance S (with similar 21 inch wheelsizes). If we assessed miles*capacity/hp though, things would look incredibly dire & dark for the Plaid; the worst EV in production perhaps?

In general, engine output capacity doesnt really tell us much.

... obviously then a floating canal train, would beat both of them. The best of both worlds!

Don't they usually stack containers two high on trains?

If you have old infrastructure with low overhead (old tunnels and bridges for example) you can't run that and you need to use rail yards to assemble/disassemble container stacks. It gets expensive fast.

Hah, fair, I've only lived in the western half of North America, where infrastructure was almost all built after heavy rail lines were laid down.

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