Nervous about space weather and your grid?
- March 27, 2014
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To me “space weather” sounds like the title of the latest SyFy Channel B-movie extravaganza scheduled somewhere between “Ice Spiders: and “Magnetic Tornado.” (And, yes those are two actual SyFy Channel movies. “Sharknado isn’t the only crazy flick SyFy’s created in the last few years.)
According to the Electric Power Research Institute’s (EPRI’s) topical expert Richard Lordan, however, “space weather” is all too real—if not as amusing or deadly as those pesky imaginary ice spiders.
Here’s the skinny on space weather—specifically solar flares. First, you take the sun, which likes to flip poles once in a while. This happens about every 11 years, and, when it does, there’s a lot of crazy magnetic activity going down—but not as crazy as “Magnetic Tornado,” no.
So, crazy magnetic activity creates a big ol’ eruption of solar “material” into space, where it has a nice little road trip over to Earth. (Yes, it can shoot toward other planets, but we don’t really care about those other planets in this story.)
It hits our lovely planet and ... mostly nothing much happens, but it can interfere with our magnetic field. (And nothing much happens because of that magnetic field, really. Look at the moon for a good example of what could happen without one.)
“The earth’s DC field gets changed in the solar storm,” Lordan said when I asked him to explain all of this like he bumped into me at an industry cocktail party. “It injects voltages and current into the transmission lines—strange currents that we’re really not used to on those lines.”
That strange current travels down those hijacked lines to transformers. Now, the transformers, which were “used to the smooth sine waves of our regular system, are now getting a goofy direct current kind of thing.”
What can happen then? Well, it can drive the transformers into saturation with three major issues:
- the transformer can get real, real hot
- the transformer can start to consume voltage, pulling the voltage of the system down
- the transformer has to deal with harmonics (or a shift from the smooth system they’re used to over to one that now has that “goofy direct current kind of thing” on top of it)
So, essentially that real thing that is “space weather” can potentially have a large impact on the power system. But, has it?
After all, if this happens every 11 years, that means it’s happened many, many times before. Has there been a real power problem traced to solar flares?
Lordan’s short answer: yes.
1989. Hydro Quebec. With a very strong solar storm, the system failed because the harmonics issue (that we talked about with transformers but can impact other equipment) knocked out some sensitive components, the voltage reduced and then collapsed. And, the end result was millions of customers without power for a number of hours.
So, to answer the question in this article’s headline, Lordan notes “utility executives are right to be concerned.”
“These solar storms create things that happen almost immediately, happen at the speed of light,” he added.
But, no worries, EPRI—along with FERC and NERC—are on the case. First on the agenda: understanding how vulnerable power systems really are.
“We’ve developed a better understanding of the science of these solar storms and how all things interact together,” Lordan added. “We know better how the transformer response impacts system reliability.”
Lordan does have some advice for utilities if a solar storm comes along tomorrow based on that better understanding:
- assess the vulnerability of your transformer fleet beforehand (you can look on the NERC website for geomagnetic disturbance mitigation [GMD] vulnerability assessments that EPRI helped put together)
- keep an eye on transformer temps during the storm and move the power around to keep the transformers cool
- make sure all generators and connected lines are up but not running at full load, giving you more headroom in the lines to absorb that “goofy direct current kind of thing” that solar flares bring
- watch your systems and coordinate
- horde a few spares in case there are some failures
While blocking technology is also available, Lordan warns that the value of those devices is still being evaluated, as is the reach of solar flares overall.
Some believe there could be serious transformer impact—on a massive, widespread scale—if a solar storm targeted the U.S. Some think that’s a stretch (including Lordan).
The debate centers around that same 1989 storm that impacted Hydro Quebec, only this time we go to New Jersey. Two transformers there failed only a couple of days after the storm. Some attribute that to the solar storm directly.
But, as Lordan philosophically added, “It’s difficult to know what killed a transformer. What kills a man? His whole life. These were old transformers.”
But, if the transformer dooms-dayers are right, could that collapse the system causing an outage that could really last months?
Lordan doesn’t think so, namely because he doesn’t believe that system operators—those watchers that keep an eye out for disorder on the orderly grid—would just sit back and let it all implode.
“They’d take action, keep as many customers up as possible, assess the threat to key equipment, move power around, drop some load. They have processes,” he said.
So, massive disruption is unlikely, but those solar flares can still have a serious impact on utilities. While Lordan admits we still have a lot to learn about solar storms, he also has faith in what the industry has learned so far—from space weather to technology upgrades—and how it can help in the future.
“This industry has gotten a lot smarter since that 1989 failure,” he said. “A lot smarter. We learned from that bad event. Sometimes, we have to learn from bad events, but that will help us get there beforehand when solar storms happen in the future.”
It seems bad events make good science—and good science fiction. Take note, SyFy.