Electrical energy does not accumulate: it's a movement of electrons, and we can't "store" a movement. The best we can do to "store electricity" (note the quote)

Electrical energy does not accumulate: it's a movement of electrons, and we can't "store" a movement. The best we can do to "store electricity" (note the quote) is to create a system that can easily produce this movement of electrons as needed. Here are two examples : - A chemical reaction that creates a movement of electric charges during the reaction. This is how your regular batteries work. Rechargeable batteries like the one found is Tesla cars, your laptop, ... use a chemical reaction that can be "rewinded" if an opposite movement of electrons is forced by an external system. - A big hole in the ground is divided in two parts with dam that is fully closed. Both parts are half full of water. To recharge the "battery", the water of the left part of the hole is pumped in the right part of the hole using electrical power. When electrical power is needed, the dam is open, and water is forced by gravity from the right part of the hole to the left part. the water passes through a turbine that generates power that can be injected into the grid. There are dozens of ways to create batteries like these, but none are actually storing electrical power. Please also note that there are no perfect batteries : you always use more energy to recharge the battery than you get when using it.