Could Terrorists Cause a National Blackout By Attacking Our Power Grid?S

Last April, an unknown number of gunmen, armed with what were likely AK-47s, crept through the dark near San Jose. Their target? A power station that provides electricity to Silicon Valley. Phones lines were cut from a manhole and more than 100 rounds were fired, knocking out 17 transformers.

We still don't know who was behind the attack, but the precise, military-style raid has some utilities experts worried that this was a dress rehearsal for a larger attack against America's aging and vulnerable electric grid.

Today Jon Wellinghoff, a former top energy official and chairman of the Federal Energy Regulatory Commission at the time of the California incident, is sounding the alarm in a Wall Street Journal article. Wellinghoff says that knocking out just a small number of substations like the one in California could cause a blackout that plunges much of the nation into darkness.

We take electricity for granted in our 21st century lives now. It seems to arrive, as if by magic, to power our devices instantaneously and continuously But in truth, the electric grid is built on fragile physical infrastructure, which is as vulnerable to physical attack as it is to hacking.

To illustrate the weakness of the electric grid, we need to look no further than the blackouts in 2003 that left much of the Eastern US and Canada in darkness. There was no malicious intent there—just trees. Yes, trees. Maggie Koerth-Baker, author of Before the Lights Go Out, explained it best at BoingBoing. Her description is a bit long, but it lays out how electric grids work and why they are vulnerable. A seemingly small, local event can turn into a large blackout:

I like to say that the grid is a lot like a lazy river at a waterpark. It's not a line, it's a loop—power plants connected to customers and back to power plants again. And like the lazy river, it has to operate within certain parameters. The electricity has to move at a constant speed (an analogy for what the engineers call frequency) and it has to flow at a constant depth (analogous to voltage). In order to maintain that constant speed and constant depth, you have to also maintain an almost perfect balance between supply and demand … everywhere, at all times. So when one generator goes out, the electricity it was supplying has to come from someplace else. Like a stream flowing into a new channel, the load will shift from one group of transmission lines to another.

But, the more electricity you run along a power line, the hotter the power line gets. And the hotter it gets, the more it droops, like a basset hound in a heat wave. If nearby trees aren't trimmed, the lines can slump too close to the branches—which creates a short circuit. When that happens, the loads have to shift again. All of this disrupts the speed and the depth on the river of electrons. The more lines you lose, the more likely it is that the remaining lines will, themselves, droop into something. The more lines that short, the more power plants have to shut down to protect themselves from fluctuations in frequency and voltage. The more times you have to shift load around, the more the grid starts to get away from you. In 2003, six transmission lines went down in a row, several of them major channels for the flow of electricity. Those losses were what turned a small series of mistakes into a catastrophe.

Could Terrorists Cause a National Blackout By Attacking Our Power Grid?S

The attack on California's Metcalf Transmissions Substation took place at 1:30 am, when demand for electricity was low, and electricity could be rerouted without putting too much strain on the system. But a well-timed attack in the afternoon? That could have turned off Silicon Valley's power and even caused a cascading blackout. The repairs to the station took 27 days to fix.

At the time, local newspapers reported the incident, per Pacific Gas and Electric's statement, as the attack of "vandals." The FBI has since investigated and says they do not think terrorists are behind the attack. No suspects have been announced.

Electric stations across the country report dozens of incidents a year, mostly the work of "metal thieves, disgruntled employees or bored hunters, who sometimes take potshots at small transformers on utility poles to see what happens," according to the WSJ. But the utilities industry had never seen a coordinated attack like the one at Metcalf. We can only hope it's learned a lesson. [Wall Street JournalBoingBoing]

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