Question

what happens when electricity produced is more than electricity consumed?

Answer 1

If power generation exceeds the load demand, the generator would tend to run faster.

At this point, the governor kicks in and reduces the input to the turbine.

In the case of a hydroelectric generator, this is done by reducing the water flow, by moving the guide vanes with the help of servo motors.

In the case of steam generators, the governor causes the steam input to reduce.

At this point, fuel input to the boiler is reduced to prevent occurrence of excess pressure.

If excess pressure builds up, safety valves open and let out the steam into the atmosphere, to protect the boiler.