Throwing cost concerns and caution to the wind, the U.S. Department of Energy is getting behind a project that aims to prove that superconducting magnetic energy storage (SMES) can work at the grid level. Via a $4.2 million ARPA-E grant, Swiss engineering firm ABB and a handful of partners plan to build a 3.3 kilowatt hour proof-of-concept SMES prototype that, if all goes well, could someday be scaled to megawatt-hour capacity.
SMES is, at its heart, a means to make a battery out of magnetic fields. The DOE is interested in the technology because it could be used to create huge facilities that would efficiently store massive amounts of electricity for use when renewable energy sources like wind and solar fail to meet grid demand. SMES devices work by storing electricity in huge magnetic fields generated by running direct current through superconducting wires. Their special geometry allows them to hold vast amounts of power while using very little energy to maintain the field.