power transmission question?

Question

if a power plant produces 1000 mw of power but the city uses say only 750 mw what happens to the remaining 250 mw.do they go waste?where does it go?

Answer 1

Do you mean what happens in a power plant with a 1000 MW capacity when the demand is only 750 MW? The answer to that is that he plant only puts out 750 MW. In a case like that, whatever is providing the energy for the plant (say a turbine engine) will not have to push as hard, and will use less fuel, than when the full capacity is needed. As an experiment, you can connect a bulb, through a switch, to a little hand-cranked generator. When the switch is off, it's real easy to turn the crank; but when the switch is turned on, you suddenly have to crank much harder to keep the light lit.