Anything you can cite here? I think of water as extremely fantasically high drag. I know that scales inversely down proportional to size, but I still think of rail as the ultra-efficient best option. Would love to read more detailed review/analysis.
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.
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.
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.
Most energy in transport goes into moving the atmosphere out of the way.
Planes fly high, but that really only makes them comparable to a car. Surprisingly that also means that for really long-range transports even rockets aren't as inefficient as you'd initially think.