California's power shortage confirms that all of the hoopla over wind energy's credentials as a clean and renewable source of electricity is undercut by the reality of its unreliability. During an extremely hot week in August, when air conditioners were cranked up and the state was on the brink of rolling blackouts, how much help did the state get from its beloved 2,500 megawatts of wind power? Only 4 percent of its capacity, according to the California Independent System Operator, which is responsible for the state's electricity grid. Southern California Edison's 2,200 megawatts of wind capacity generated only 45 megawatts. In other words, wind energy works great — except when you need air conditioning.