What is an electric grid?
The largest machine ever built, and why it has to balance every second.
An electric grid is the network of power plants, high-voltage transmission lines, substations, and local distribution wires that delivers electricity from where it's made to where it's used. The defining fact about a grid is that it can't really store power at scale in the act of using it. Supply and demand have to match, instant by instant, or frequency drifts and equipment trips offline.
That balancing act is the job of a grid operator. Across a synchronised area, such as North America's Eastern Interconnection or continental Europe's grid, every generator spins in lockstep at the same frequency (60 Hz in the US, 50 Hz in Europe). Keeping that frequency steady while demand rises and falls, plants trip, and weather swings wind and solar output is, second for second, one of the hardest coordination problems humans run.
Frequently asked questions
What is an electric grid?
The interconnected system of power plants, transmission lines, and distribution wires that moves electricity from generators to consumers while balancing supply and demand every second.
Why does the grid have to balance instantly?
Because electricity is consumed the moment it's produced. If supply and demand fall out of step, grid frequency drifts, and protective systems shut equipment down to avoid damage. That's how blackouts cascade.