How Efficient is a 200Kw Petrol Engine When Driving an Electric Generator?

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Generator output question...

Hi there,

If I were to drive an electric generator from, for example, a 200Kw petrol engine, would the output of the generator also be 200Kw, or would I loose some power along the way? And if so, why?

Many thanks.
 
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Longbow said:
Hi there,

If I were to drive an electric generator from, for example, a 200Kw petrol engine, would the output of the generator also be 200Kw, or would I loose some power along the way? And if so, why?

Many thanks.

You would lose power due mostly to the engine having to overcome friction in both the engine itself and in the generator.
 


You'd lose power from the frictions inherent in the engine and from resistances inherent in the cables.
 


Thank you all for your replies. I didn't think it could as simple as my theory suggested.

Leading on from my first question; if I were to have:

A. An engine driving a generator, as above, to power an electric motor.

and

B. An identical engine driving a hydraulic pump powering a hydraulic motor.

As a rule of thumb, which system would be more efficient in terms of power loss between engine and motor?

I suppose a parallel example would be diesel-electric and diesel-hydraulic trains.
 


In general, electrical systems are more efficient than hydraulic systems.