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vk6kro
#19
Feb20-12, 08:10 PM
Sci Advisor
P: 4,027
This implies that because power can be generated, it has to go somewhere. This just isn't true.

Take a simple example.

If you have a large car battery capable of delivering 600 amps (that is 7200 watts), is it safe to put a 1000 ohm quarter watt resistor across it?
Would the battery blow up with all that power inside it? Will the resistor be vapourized in an instant?

No, the battery will be fine and so will the resistor.

There will be a current of about 12 mA flowing in the resistor and it will not even get warm with only 144 mW being dissipated in it.

It is the same with the power grid. It only delivers power if the load takes power from it. There is no power "bottled up" in the generators trying to get out.

Each component connected to it is arranged with its own protection so that if there was no load or too much load, the equipment would not be damaged.

For example, a wind generator may tend to spin too fast if it has no load on it. So, it can be turned away from the wind or the blades might be set to present no surface area to the wind.

The equipment is never sacrificed to supply a demand. If there is too much load, power can just be turned off to consumers, possibly only in a few suburbs, preferably the ones that didn't vote for the current government.

Large power stations cannot be just switched off, but they continue to generate the standard voltage whether or not much current is taken from that supply.
As the load increases, it gets harder to turn the generators, so more drive power is used.