The Grid: Electrical Infrastructure for a New Era

by Gretchen Bakke

More poetically and of equal technical relevance is that different kinds of electric lines are not identified by long strings of numbers and letters but rather are named after birds. So, for example, a 765 kilovolt (kV) partridge line that runs one hundred miles has a maximum carrying capacity of 3.8 gigawatts (GW)—or 3.8 billion watts, roughly the electricity needed to light 10 million 100-watt bulbs or all the homes in Columbus, Ohio. Now take that same partridge conductor, stretch it to four hundred miles, and it can carry only 200 GW, about half as much power. Distance reduces the carrying capacity of lines, whereas long-distance wheeling increases the amount of electricity transported over precisely these same lines. The Energy Policy Act did nothing to upgrade the lines. The result was a simple one. The free trade of electricity meant that there was too much electricity traveling too far. Lines were getting overburdened, heating up, sagging, shorting out, arcing, and filling with harmonic resonances. All of which are both very bad for reliability and wasteful, and thus bad for efforts at conservation.