And further, for very large ships, like I don’t think you’ll ever replace the steam turbine. I think you get into scaling problems with transmissions with gas turbines beyond a certain level.
So we’ve just gone from using coal, to oil, to nuclear energy, to run boilers to make steam to drive steam turbines to drive screws.
If you ever get a chance to go see the guts of one of the several U.S. retired WWII battleships or aircraft carriers that are on display around the country, looking at the boiler rooms is fun. Well, it is for me.
;-P
I'm a "propulsion guy" too - have seen the Midway (San Diego) and the Lexngton (Corpus Christie) - boiler rooms a sight to behold.
Hoover Dam turbines (pre- 911) was fun to see, too.
I got to see the one in the old merchie in San Francisco they used for engine room scenes for Titanic. Very cool!