– If the electrical grid overproduces on electricity, what happens to that excess?

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– If the electrical grid overproduces on electricity, what happens to that excess?

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Depends on where you are. Some electrical grids can absorb excess power and store it in various ways (water can be pumped up into reservoirs, huge batteries are used, a much smaller amount of energy is stored in gigantic flywheels). Usually, though, power plants have to cut back since it will destabilize the grid.

Answer:

The electrical grid is really multiple areas of use and production that are all connected. So if one area over produces they can sell the electricity to another area. Some overproduction is purposeful as some electricity is lost as heat loss during transmission. But purposeful overproduction helps areas make profits. The USA sells electricity to Canada and Mexico for example.

[This article ](https://www.eia.gov/energyexplained/electricity/electricity-in-the-us-generation-capacity-and-sales.php) Has more of you’re interested

Powerplants don’t really produce any significant excess in the first place. They have a lot of data to try to match current demand patterns. Otherwise they’re just running the generators and incurring wear and tear and maintenance costs for nothing. So if demand is low and expected to be low, they dial down some of generators or even turn them off completely. But turning generators off completely has its own set of problems, because generators also take a long time to turn on from a cold start. So you can’t respond easily to a high demand

As each generator is pushing power into the grid, consumers are pulling power out of the grid. So there’s always this balancing act of power in and power out. The rated electrical standard for US is 110v or 220v for Europe. But the actual live voltage always varies up and down a few volts. Sometimes when you have sudden demand, the voltage drops too low, and you get what’s called a brown out. You still have electricity but it’s not enough juice to get high power items going. It might turn on the lights but the washing machine can’t run.

The grid will being to produce electricity at the wrong frequency. Electricity is made by spinning turbines (with the exception of solar). Wind, steam, or water spins a turbine, which spins a magnet in a generator to “push” electricity around the grid. The generator is supposed to spin at a certain rate (60 Hz in the US), because electrical devices are designed to work with electricity that oscillates at that rate. If there is a lot of electricity being used, the generator can’t push hard enough to spin at 60 Hz, so it slows down. If there isn’t much electricity being used, the generator pushes too hard and spins too fast. Either way is bad, as electrical devices expect 60 Hz electricity. So, people running the electrical grid try to keep it balanced. The balance doesn’t have to perfect, as if the electricity slows down to 59.99 Hz, that’s not a big deal, but a big imbalance would be bad. So, if it’s getting out of balance, there can be things like flywheels that store or release some energy to keep it balanced, or they’ll turn off or on some generators to reduce or increase the amount of energy created, or do lots of other things to keep the produced amount matching the used amount of electricity.

There are basically one of 3 things that happens.

1) It gets stored for later use: pump hydro back upstream, batteries, etc…

2) It gets sold on the energy markets to neighbors. Quite often local electric grids are connected to other markets and allow the selling of wholesale electricity

3) reduce production of electricity. essentially balance production with consumption. If you have variable electricity rates in your area this is when the price of electricity can drop.