Superconductor technologies are increasingly making their way into electricity grids, as two recent deals illustrate.

Superconductor startup Zenergy Power (AIM: ZEN) has landed a contract to deliver a higher-voltage version of its superconductor fault current limiters now being used on distribution grids.

The deal is with American Electric Power, and calls for the London-based startup to deliver a fault current limiter for the utility's 38-kilovolt Tidd transmission substation near Steubenville, Ohio, in late 2011.

And Devens, Mass.-based American Superconductor Corp. (NSDQ: AMSC) has signed a five-year agreement with Korea's LS Cable to supply wire superconducting cables for the nation's power grid.

LS Cable is already installing a superconducting cable distribution system for national utility Korea Electric Power Corp., expected to be up and running in 2010 (see Superconductors for the Grid).

The new agreement means that LS Cable will be seeking customers for similar projects in what it has estimated to be a $1 billion market, said Jason Fredette, American Superconductor director of investor and media relations.

Superconductors are materials that can carry far more electricity than traditional copper wires. Among their useful functions are carrying lots of power in narrow underground tunnels instead of massive overhead transmission lines.

American Superconductor has seen its superconducting wire used in cables for such projects by AEP, as well as New York's Long Island Power Authority, in what was the first underground transmission voltage level superconductor cable system.

Superconductors also give the ability to prevent current surges from damaging the grid. That's because some superconductors turn from conductors into resistors when current grows too great.

The tricky part is, they require super-cooling to keep their very high temperatures in check. Still, they've seen increased use as an alternative in certain situations.

Both Zenergy and American Superconductor are working on fault current limiter systems with the assistance of grants from the Department of Energy.

Zenergy's AEP project will get part of its funding from $11 million the Department of Energy gave Zenergy's San Mateo, Calif.-based subsidiary in 2007, and American Superconductor got $21.7 million from DOE in 2007 to work on fault current limiter and power delivery equipment.

Zenergy's AEP project is the first publicly announced fault current limiter for an electricity transmission system in the United States, though others have been done for distribution-scale grid systems.

Zenergy, for example, is doing distribution grid superconductor fault current limiters for Southern California Edison. And both Zenergy and American Superconductor have worked with Consolidated Edison as part of the $39 million Department of Homeland Security-funded project HYDRA (see Green Light post).

Both companies were early recipients of the DOE's smart grid demonstration grant program, with Zenergy getting $8.1 million and American Superconductor getting $4.8 million to work on fault current limiter technology with German electrical engineering giant Siemens (see DOE Hands Out $47M For Smart Grid Demos).