**Energy storage** is the storing of some form of energy that can be drawn upon at a later time to perform some useful operation.

The following outline is provided as an overview of and topical guide to energy storage:

## Types of energy storage[edit | edit source]

- Pumped-storage hydroelectricity
- Superconducting magnetic energy storage
- flow batteries
- Conventional batteries (
*e.g.*rechargeable electricity storage system) - Gas holder
- Grid energy storage
- Fuel cell and hydrogen technology
- Gravitational mass
- Capacitors (
*e.g.*rechargeable electricity storage system) - Electromagnetic mass
- Mainspring
- Thermal energy storage
- Solar chimney
- Compressed fluids (
*e.g.*compressed air) - flywheels
- Vacuum storage (in rush generation technology)

## History of energy storage[edit | edit source]

*Main article: History of energy storage*

## General energy storage concepts[edit | edit source]

1. Using a high density magnetic field. Energy [math]\displaystyle{ E }[/math] in terms of magnetic field strength [math]\displaystyle{ B }[/math] is

[math]\displaystyle{ E = \frac{1}{2}B^2 = \frac{1}{2}Li^2 }[/math]

where [math]\displaystyle{ L }[/math] is the inductance of the electromagnet and [math]\displaystyle{ i }[/math] is the current.

## Energy storage scholars[edit | edit source]

## Leaders in energy storage[edit | edit source]

## See also[edit | edit source]

## External links[edit | edit source]

- U.S. Dept of Energy - Energy Storage Systems Government research center on energy storage technology.