Remember before, before when people read… what were those things called? Paper News? Something like that, eh? Well, an event reminded me of the good old days.
I was scanning my RSS subscriptions on the laptop with Google Reader and Matthew L. Wald told me what was happening out my back door. (Actually, I can’t see it from the back door, I can see it from the upstairs office window, but I am nothing if not a product of the CCR generation.)
“As ordered by a computer, the AES Energy Storage plant in Johnson City, N.Y., absorbs or delivers energy to the grid at intervals of five seconds with thousands of lithium-ion batteries.”
I didn’t know that such a thing was happening until a NY Times green blogger informed me that “frequency regulation is as critical as voltage control or generating capacity but is not something that most customers notice.” Good cause for a Zemanta-enhanced post.
The problem is that the North American electric grid is supposed to run at 60 cycles, meaning that the electrons change direction 60 times each second. In practice, if electricity supply and demand are not perfectly matched at every instant, the system runs just a little bit too fast or too slow.
If the pace strays too far from 60 cycles per second, equipment like pumps and motors run too fast or too slow and a variety of equipment will shut down to avoid getting damaged. A sharp decline in frequency was one reason that the blackout of August 2003 spread as far as it did.
Traditionally utilities maintained the balance on a gross level by adding or subtracting generation and then fine-tuning by running a steam turbine, usually at a plant that runs on coal, a little faster or a little slower. Those turbines, which have a great deal of inertia at any given moment, could deliver or supply large amounts of energy promptly. But as more electricity generation has shifted to gas turbines, which resemble jet engines and have less inertia, or to wind generators, which tap the fickle breeze, the fraction of plants that can accomplish frequency control has declined.
But on New Year’s Eve, AES Energy Storage, the subsidiary of a company based near Washington that operates power plants around the world, opened a plant in Johnson City, N.Y., near Binghamton, that sells frequency regulation. It absorbs or delivers energy at intervals of five seconds, as ordered by a computer at the New York Independent System Operator, which runs the state’s grid.
It does so with thousands of lithium-ion batteries, which AES selected for the same reason that electric vehicle manufacturers like them: they have the ability to absorb or deliver large amounts of current promptly and can change direction easily. The batteries were built by A123, which also builds batteries for automobile use.
Batteries are a better bet than turbines, said John M. Zahurancik, vice president of operations and deployment at AES. “You’re not revving these big engines up and down, you’re running a device that doesn’t care if it’s run up and down,’’ he said.