Sunday, November 24, 2002
Jim says the fault lasted 20 milliseconds before breakers tripped. (The breakers for a wire like this are pretty amazing in their own right. They use high pressure gas to blow out the arc as the circuit begins to open. Anything that can cut off this number of megawatts [230kV at about 700 amps –Sean] in 20 ms gets my respect.) It blew carbonized oil about 3000 feet down the pipe to either side of the fault. (Compute velocity … )
The term “pornography” here is used in the sense of “more detail than you ever wanted to know” rather than “lewd sexual content” (much like CNN is “news porn” and the Food Channel is “food porn”). And I find such engineering feats fascinating, primarily because such engineering feats have to be done right or you waste tons of money (it's not to say that engineering mishaps don't happen—the space shuttle Challenger, Three Mile Island and Bhopal come to mind but given the extent of our infrastructure those events are probably rare. As Feynman said, “You can't fool nature.”). And I can't but help marvel at the inginuity used, such as using liquid nitrogen to freeze the oil dielectric to form ad-hoc end caps in the pipe so it could be repaired since the oil used is very expensive and a large enough reserve of oil could not be found in time, or using a car battery and a millivoltometer to locate the short.