Coil energy storage principle

How does a superconducting coil store energy?

First, some materials carry current with no resistive losses. Second, electric currents produce magnetic fields. Third, magnetic fields are a form of pure energy which can be stored. SMES combines these three fundamental principles to efficiently store energy in a superconducting coil.

How does a superconductor store energy?

The Coil and the Superconductor The superconducting coil, the heart of the SMES system, stores energy in the magnetic fieldgenerated by a circulating current (EPRI, 2002). The maximum stored energy is determined by two factors: a) the size and geometry of the coil, which determines the inductance of the coil.

How to design a SMEs coil?

A primary consideration in the design of a SMES coil is the maximum allowable current in the conductor. It depends on: conductor size, the superconducting materials used, the resulting magnetic field, and the operating temperature. The magnetic forces can be significant in large coils and must be reacted by a structural material.

What temperature should a superconducting SMEs coil be kept at?

Cryogenic Refrigerator The superconducting SMES coil must be maintained at a temperature sufficiently low to maintain a superconducting state in the wires. As mentioned, for commercial SMES today this temperature isabout 4.5 K (-269°C, or -452°F).

What is energy storage technology?

This technology is based on three concepts that do not apply to other energy storage technologies (EPRI, 2002). First, some materials carry current with no resistive losses. Second, electric currents produce magnetic fields. Third, magnetic fields are a form of pure energy which can be stored.

What is superconducting magnetic energy storage (SMES)?

Pumped hydro generating stations have been built capable of supplying 1800MW of electricity for four to six hours. This CTW description focuses on Superconducting Magnetic Energy Storage (SMES). This technology is based on three concepts that do not apply to other energy storage technologies (EPRI, 2002).