It took snipers 19 minutes to knock out 17 transformers last year at PG&E Corp.’s Metcalf, California transmission substation. The attack is “the most significant incident of domestic terrorism involving the grid that has ever occurred,” said form Federal Energy Regulatory Commission chairman Jon Wellinghoff. He, along with FERC officials, the FBI and experts from the U.S. Navy’s Dahlgren Surface Warfare Center which trains with SEAls concluded it was a professional job. As reported in The WSJ by Rebecca Smith:
“This wasn’t an incident where Billy-Bob and Joe decided, after a few brewskis, to come in and shoot up a substation,” Mark Johnson, retired vice president of transmission for PG&E, told the utility security conference, according to a video of his presentation. “This was an event that was well thought out, well planned and they targeted certain components.” When reached, Mr. Johnson declined to comment further.
A spokesman for PG&E said the company takes all incidents seriously but declined to discuss the Metcalf event in detail for fear of giving information to potential copycats. “We won’t speculate about the motives” of the attackers, added the spokesman, Brian Swanson. He said PG&E has increased security measures.
Utility executives and federal energy officials have long worried that the electric grid is vulnerable to sabotage. That is in part because the grid, which is really three systems serving different areas of the U.S., has failed when small problems such as trees hitting transmission lines created cascading blackouts. One in 2003 knocked out power to 50 million people in the Eastern U.S. and Canada for days.
Many of the system’s most important components sit out in the open, often in remote locations, protected by little more than cameras and chain-link fences.
Transmission substations are critical links in the grid. They make it possible for electricity to move long distances, and serve as hubs for intersecting power lines.
Within a substation, transformers raise the voltage of electricity so it can travel hundreds of miles on high-voltage lines, or reduce voltages when electricity approaches its destination. The Metcalf substation functions as an off-ramp from power lines for electricity heading to homes and businesses in Silicon Valley.