US energy regulators' efforts to protect the power grid against snipers and terrorists were fuelling a debate whether resources were being diverted from other threats, like cyber attacks.
The power industry had been last week ordered by the Federal Energy Regulatory Commission to identify critical facilities and work out a plan to protect them from attack.
Bloomberg quoted John Norris, a FERC commissioner who voted for the order even as he cautioned against overreacting to the sniper attack last year on a power substation in California, that his concern was that the focus and resources should not shift.
He added, the rush to do this seemed to be based on a very incomplete set of facts about what happened.
With the electricity network becoming increasingly dependent on software and the internet, the utility industry had focused on the threat from potential cyber attacks.
However, the April attack at Pacific Gas & Electric (PG&E's) Metcalf substation near San Jose came as a reminder that an old fashioned 20th century threat, a military-style assault on the power network too needed to be guarded against.
Regulators are now looking for the best way to guard against all threats to the generators, transformers and thousands of miles of high-voltage power lines that made up the US electric grid.
Meanwhile, The Wall Street Journal reports that the US could suffer a national blackout if attackers knocked out just nine of the country's electric-transmission substations on a hot summer day, citing a previously unreported study by the Federal Energy Regulatory Commission.
According to the study coordinated attacks in each of the nation's three separate electric systems could knock out the entire network, the newspaper reported Wednesday, citing people familiar with the agency's research.
According to the commission, the three electrical systems that served the entire nation could black out if as few as nine of the country's 55,000 electric-transmission substations were hit in the East, the West and in Texas, according to the report.
According to Ross Baldick, a professor of electrical engineering at the University of Texas at Austin, who spoke to the newspaper that would be an event of unprecedented proportions.
The Wall Street Journal said, the results of the study results were known for months to the White House, Congress and officials at federal agencies, who had been briefed by then-FERC chairman Jon Wellinghoff and others at the commission.
Wellinghoff has voiced concerns about an April 2013 attack on Pacific Gas & Electric's transmission substation in Metcalf, California, that lasted 52 minutes and knocked out 17 transformers.