No, that is just for aux power on some ships. They don't run all the generators (typically 3) at once. These generators power all the ships systems, pumps, lighting and giant compressors uses to start the engine. Some container ships use the main engine for propulsion only (direct drive to the prop) and others have mega generators running electric motors driving the prop. The facts for these boats are staggering. The newest generation are larger than aircraft carriers.
The Emma Maersk is a new generation hybrid with the following engine compliment:
She is powered by a
Wärtsilä-Sulzer 14RTFLEX96-C engine, the world's largest single diesel unit, weighing 2,300 tonnes and capable of 109,000 horsepower (81 MW) when burning 3,600 US gallons (14,000 l)
[32] of
heavy fuel oil per hour. At economical speed, fuel consumption is 0.260
bs/hp·hour (1,660 gal/hour).
[33]She has features to lower environmental damage, including
exhaust heat recovery and
cogeneration.
[34] Some of the exhaust gases are returned to the engine to improve economy and lower emissions,
[35] and some are passed through a steam generator which then powers a Peter Brotherhood steam turbine and electrical generators. This creates an electrical output of 8.5 MW,
[36] equivalent to about 12% of the main engine power output. Some of this steam is used directly as shipboard heat.
[37] Five diesel generators together produce 20.8 MW,
[36] giving a total electric output of 29 MW.
[27] Two 9 MW electric motors power the main propeller shaft.
[36][38]
http://en.wikipedia.org/wiki/Emma_Mærsk
That's over $100K per day just for fuel.
