The operation of an electrical grid is a balancing act – you have to produce *exactly* the same amount of energy as is needed, otherwise bad things happen. I don’t understand how does this rule apply on anything other than the largest scale of things.
I understand that *in general* you can predict a higher load on the grid during Monday evening when everyone is at home, and plan your energy production accordingly. But a power station can’t predict smaller load fluctuations like if I decide to turn on or off my TV at this very moment.
So, how does the electrical grid cope with unpredictable load that differs from the planned & expected one?
In: Engineering
The vast amount of energy in the grid is barely affected by a single lightbulb, so it’s just not noticeable at that level.
You’re correct that the grid is a balancing act, but the energy is equally shared across all appliances that are plugged into it. As long as the total outgoing is less than the total generated, the appliances will function correctly. If too many appliances were switch on at the same time though, all the appliances would suddenly stop working correctly until generators could ramp up and this is called a “brown out”. All the appliances are getting power, but it’s too little power. In a “black out” the grid has gone offline entirely and no appliances are getting power at all.
>So, how does the electrical grid cope with unpredictable load that differs from the planned & expected one?
It’s not really the “grid”, it’s the generators. Generators are not just generating X units of energy and that’s all there is. Rather, it’s more like when you’re running on a treadmill and the difficulty of the treadmill is changed. If the difficulty is increased, you might slow down for a moment but you quickly adjust and speed up again by putting in more effort. Generators also adjust their “effort” according to demand. Problems only happen when the demand changes so much that the generator can’t adjust to match it.
EDIT: Just to clarify, appliances (and I mean anything that uses electricity, not just toasters) are engineered to accept a range of power, not one specific amount of power. The input can dip down a certain amount and the appliance will continue to work just fine. It’s only a problem if the input varies outside the engineered range.
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