It’s been almost a year since a sniper in Silicon Valley attacked the Pacific Gas and Electric substation in San Jose. Using a rifle, the shooter took out 17 of 23 transformers -- and he's still at large.
The damage did not result in outages, but it did reveal a very uncomfortable truth about the vulnerability of the U.S. power grid. A memo put out by the Federal Energy Regulatory Commission in June warned that if nine key substations were destroyed, along with one transformer manufacturer, the entire United States power grid would be down for at least 18 months, probably longer.
One way that terrorists could cause a nationwide 18-month blackout is by taking out multiple high voltage transformers, or “big metal boxes that are filled with coils,” as Granger Morgan, head of the Department of Engineering and Public Policy at Carnegie Mellon, calls them.
Transformers are crucial because electricity is generated at a fairly low voltage. But it’s way more efficient to transport power at a significantly higher voltage. To do this, you need transformers to move electricity from lower voltages to higher voltages so it can travel through power lines. Then a second transformer is needed to drop the electricity back down to voltage that can be sent to the end user.
When a large high voltage transformer is damaged, it typically takes one and half to two years to build and deliver a replacement.
“Until recently we had stopped making most high voltage transformers in this country. For the most part they are made abroad,” says Morgan.
Transformers can weigh hundreds of thousands of pounds,shipping them overseas can take months. And they are super expensive -- up to $8 million apiece -- which is why we don’t have a bunch of spares laying around.
Although a nationwide outage from a terrorist attack is unlikely, major blackouts are increasing dramatically.
“It happens during storms, during various other emergencies and with the increase of extreme weather that we have been experiencing,” says Massoud Amin, a former director of security research at the Electric Power Research Institute.
From the 1950s to the 1980s, major power outages averaged about five a year. From 2008 to 2012 those outages occurred between 70 and 130 per year. He says building a more resilient grid would cost $17 to 20 billion a year, for 20 years.
“That’s very conservative,” says Amin.
The good news, he says, is that it would create more than 200,000 new jobs and the savings from a more efficient grid would far outweigh the cost. But until funding is made available, the only short term solution is to increase security at substations, and prepare for the inevitable blackouts.