This is an affect of electric deregulation. This is very little incentive for any power company to build generating capacity to absorb these peaks. The rolling blackouts are spread between the customers of all power companies so any one company can't benefit. Its going to get a lot worse. Sean Donelan wrote:
As you may remember in may the NERC, the National Electrical Reliablility Council issued a press release announcing that generation and transmission resources are expected to be adequate in most areas this summer.
Today's New York Times has a story about the close call in California yesterday. Available electrical capacity dropped near 3% reserve in the afternoon, leading to concern CAISO would need to declare a "stage three emergency" and begin controlled rolling blackouts across california.
http://www.nytimes.com/library/national/080300ca-power.html
In June, PG&E used rolling blackouts around the San Francisco Bay area.