German electric motors use metric horsepower [ PS] measures for mechanical power capacity/output.
Power is PS , and 1 PS =735.5 watts.
US electric motors are stated in HP...like a "3/4 HP motor...."
And 1 HP = 746 watts.
So 1 HP is close to a Metric PS.

So , your 1.1 kw starter is approx 1.5 PS [ ISO Horsepower]
You alternator has ZERO mechanical output. But it has 80 AMPS electrical output capacity.
One is a Mechanical power measure and the other is an Electrical measue ..and completely different...
Many German starters will be stamped right on the case " 1.4 SP ..or 1.8 SP, etc "

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A Dalton