Since, and unless electricity has properties I’m not aware of, it’s not possible for electric power plants to produce only and EXACTLY the amount of electricity being drawn at an given time, and not having enough electricity for everyone is a VERY bad thing, I’m assuming the power plants produce enough electricity to meet a predicted average need plus a little extra margin. So, if this understanding is correct, where does that little extra margin go? And what kind of margin are we talking about?
In: Engineering
Most electricity is made by spinning turbines that are linked to generators, these turbines have something pushing against them (steam, water, or air), the force being used to push the turbine around is transmitted through the cables as an electrical “push”.
When the electricity reaches the end user, it can push on whatever the end user is trying to use, let’s say an electric fan, and push the blades of the fan around and push air to make a breeze. The physical push used to spin the turbine is converted to an electrical push by the generator, then to another physical push by the fan. This all happens at the same time, if the electric fan is switched off, there is less push needed on the turbine and so the push of the water, air, or steam will cause the turbine to speed up. The amount of push going into the system needs to match the push coming out of the system.
A small speed up isn’t much of a problem, but if the turbine speeds up too much it can cause bits of the system to break or cause damage to things connected to the electrical grid that depend on the speed being steady.
In reality, there are loads of turbines all connected together so they spin at the same speed and the pushes on the turbines all push on people’s devices. The amount of pushing is balanced between all the turbines, if less pushing is needed then all the turbines will speed up together, and if more pushing is needed, the turbines will slow down. Power stations will change the amount of pushing they do to their turbines to keep them all spinning at the same speed.
People’s devices can take an electrical push and change it to various other types of work, this could be light, movement (like a fan or food mixer), heat (like an electric fire or kettle), or to figure stuff out in a computer. Different devices need different amounts of electrical push to work.
Latest Answers