Superconductors as Electrical Grid Surge Suppressors

securitas writes "The New York Times published a story about Intermagnetics -- a company that plans to use 'superconductors as valves on the electric-utility power grid, letting their temperature rise to choke off the flow of power,' a day before the largest blackout in North American history. The timing couldn't have been better. On the day of the blackout, Intermagnetics announced a $6 million contract from the Department of Energy to develop and install superconductor 'valve' prototypes by 2006 in the Niagara Mohawk distribution system. Considering that one of the leading theories for the cause of the cascading blackout is a surge in the Niagara Mohawk power grid, this announcement seems incredibly timely."

Comments

Intermagnetics hype

[Animats]

This is hype. That technology isn't ready for prime time. Read the paper. The "high temperature superconductor" they're using needs temperatures below that of liquid nitrogen.

Utilities have been testing various superconductive devices for decades, but nobody has deployed them in volume. Superconducting generators have been built by GE and others, but they only offer an 0.5% efficiency improvement over conventional machines. That's not enough to compensate for the added complexity of running a big machine at cyrogenic temperatures.

If this technology worked at liquid nitrogen temperatures, it might have a chance. But anything that needs to go colder than that is probably going to be more expensive and less reliable than what's used now. Scroll down to the end of the article and see the comments from utility companies.

Look who's doing this: General Atomics and LANL, the senior activity centers for over-the-hill bomb designers.

If room-temperature superconductors are ever developed, all this will change, but right now, this is basically big-budget overclocking.

Re:Problems

[theMightyE]

Actually, the problem is that when the device *does* break, it heats up a LOT. That means that the liquid nitrogen is no longer a liquid. It vaporizes so quickly that you have to have a pressure-release valve to avoid an explosion. Assuming your device doesn't melt, cooling it back down again is a lenghly process.

Very true - as a student I used to work at a superconductor research lab that did this kind of work. We would run 100kA through a superconducting coil cooled with liquid nitrogen as part of our experiments, creating a magnetic field with about 3 megaJoules of stored energy. One day a tech mis-wired part of a safety circuit that was used to dump the energy at the end of the experiment run (and then very nicely faked his check-off sheet afterward), and the superconductor heated up so fast it vaporized the one inch aluminum stabalizing rod it was attached to as well as several hundred gallons of liquid He. A nine inch port blew out of the top venting all the (now gasseous) helium into the lab and we all ran like hell to avoid being smothered by the sudden lack of O2 in the room.

Nobody got injured (except the tech, who got fired), but I couldn't help but think about the alternate scenario where the lab staff somehow got trapped inside the room, and the last thing I'd hear before passing out would be "We're all gonna die!" in a Mickey Mouse helium voice.