(Businessweek) There are 3,200 utilities that make up the U.S. electrical grid, the largest machine in the world. These power companies sell $400 billion worth of electricity a year, mostly derived from burning fossil fuels in centralized stations and distributed over 2.7 million miles of power lines. Regulators set rates; utilities get guaranteed returns; investors get sure-thing dividends. It’s a model that hasn’t changed much since Thomas Edison invented the light bulb. And it’s doomed to obsolescence.

It’s not just the grid that’s at risk … so’s that solar panel on your roof. Read “A Nation Forsaken” (Autographed)

That’s the opinion of David Crane, chief executive officer of NRG Energy, a wholesale power company based in Princeton, N.J. What’s afoot is a confluence of green energy and computer technology, deregulation, cheap natural gas, and political pressure that, as Crane starkly frames it, poses “a mortal threat to the existing utility system.”

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