<tryingtobeunreasonablyhelpful>
IGNORING LOSSES
The power rating of the motor - 1hp - is a limit that describes what it is capable of doing without overheating or stalling. How much electrical power it consumes and how much mechanical output it delivers is determined by the external conditions, not by its 1hp rating. It does not use 1hp equivalent of electrical input all the time it is operating. If one generator uses 1/4 hp mechanical input and produces 1/hp electrical equivalent output, then it will demand 1/4hp mechanical output from the motor which will in turn consume 1/4hp equivalent electrical input. Two such generators will demand 1/2hp mechanical total from the motor, which will then consume 1/2hp equivalent electrical input. What the motor consumes from the grid equals what you draw from the generators. Nothing lost, nothing gained.
Except.... LOSSES! In a setup like this, you could expect 50-60% throughput efficiency. So the motor will use say 1.25hp equivalent of electrical input to make its 1hp mechanical, and the generators will turn that into perhaps 0.7hp equivalent electrical output. The rest is lost as heat.
</tryingtobeunreasonablyhelpful>
<ordinarylucien>
Motor-generators were a standard and legitimate technology for converting one frequency or voltage to another and 75 years ago were in widespread use. I own probably 10 or more of various sizes up to 100hp. But they were always lossy and people put up with their low efficiency because they could do things that were near impossible to do any other way. Nowadays, electronic conversion is the norm and most motor-generators have been consigned to scrap.
</ordinarylucien>
