Fortnightly Magazine - May 2008

What Happened in ERCOT

Voltage sag shows value of accurate wind forecasting.

Variability is a well-known characteristic of windpower, and system operators know they must plan for changes in wind generation over the course of a day. But when those plans fall short, voltage levels can drop quickly, forcing grid operators to dispatch resources to make up the difference—either by shedding load or bringing reserve generation online.

That’s exactly what happened in ERCOT on an evening in February, when a combination of events left the system operator short on power and long on demand (See Figure 1).

Green Heroes

Utilities can transform the world’s energy economy.

Perceval’s sagas are largely forgotten today, but at least one of them serves as a useful metaphor for an industry seeking the proverbial Holy Grail of clean-energy technology—specifically, the tale of Perceval and the Fisher King.

Finding the 'Sweet Spot'

As president and CEO of ISO New England, Gordon van Welie has his feet planted firmly on each of two sides of a cultural divide. First, as a transmission system operator, van Welie must keep the lights on and the wires humming. At the same time, he must run a regional market—an ongoing experiment in freewheeling capitalism in an industry fraught with more long-term uncertainty than perhaps any other.

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