Lights Out - By Douglas Birch

A well-planned attack by terrorists could cut electric power to large regions of the country for weeks or months, cost hundreds of billions of dollars, and cause thousands of deaths during heat waves and cold snaps, says a newly-declassified report by the National Research Council.

The authoritative 2007 study, released today after a five-year delay, focused most of its concern on physical attacks on transmission lines and transformers and concluded that another major concern, cyber sabotage, by itself was "unlikely to cause extended outages" and inflict major damage.

Officials and engineers have long worried about the potential vulnerability of the U.S. transportation, banking, and electrical systems to malicious hackers. Those concerns intensified following the disclosure in 2010 that the Stuxnet computer worm had crippled hundreds of uranium-enrichment centrifuges in Iran.

But the formerly secret report to the Department of Homeland Security focuses more on the U.S. electric power system's older technology and lack of spare capacity, saying the "physical capabilities of much of the transmission network have not kept pace with the increasing burden that is being placed on it." As a result, it found, sophisticated physical assaults against key facilities could damage difficult-to-replace hardware and cause multiple cascading failures with catastrophic results.

M. Granger Morgan, chairman of the National Research Council panel and a professor at Carnegie Mellon University, said that bolstering the nation's electric grid could help maintain critical social services during natural disasters as well as terror attacks. With the number of extreme weather events apparently on the increase, he said, upgrading the electric infrastructure is increasingly important.

The report noted that due to government-supported efforts to create a competitive energy market, the rickety power grid is being used for something the authors say it was never designed to do -- move power between regions. The new energy market "hasn't made us more physically vulnerable," Morgan said. But it has "complicated" the question of who is responsible for maintaining the system, he said, and "we're stressing the system more."

The DHS classified the entire document after a lengthy review ended in 2008 -- even though the experts who wrote it believed that it contained no restricted information. "We were very careful in writing this not to say anything that wasn't in the open literature, chiefly because we didn't want to write a cookbook on how to attack the electric power system," Morgan said.

After an appeal by the council, the department reversed itself in August and declassified all but several pages. DHS officials did not immediately respond to a request for comment.