Will Space Weather Blow Out My Solar Panels?

You have probably heard by now that there’s a big solar storm on its way toward us. (If not, sign up for Heatmap AM , our daily roundup of climate and energy news.) On Wednesday, the sun started ejecting massive columns of geomagnetic activity out into space in Earth’s direction. That geomagnetism is due to arrive around 11p.m. ET on Friday, triggering huge fluctuations in the Earth’s geomagnetic field.

Those fluctuations can actually generate their own electric current. And too much of that current can wreak havoc on the electrical grid.

The last time we got a heads up like this about a geomagnetic surge of this magnitude was in 2005, when coal generation was close to its peak in the U.S. and renewables were providing less than half the energy they do now. So how does that changing energy mix affect the risk to the grid this time around?

Not too much, said representatives from the National Oceanic and Atmospheric Organization on Friday morning. The other thing that’s happened since 2005 is that we've started paying a lot more attention to space weather — which, despite its name, bears little resemblance to Earth weather — which means grid operators are a lot better prepared to deal with it.

“We’ve been working with the power distribution community over the past decade to help them better understand space weather,” Rob Steenburgh, a space scientist with NOAA, said in a press briefing. “And their engineers have taken that information and used it to build systems that can protect the power lines more rapidly than they could before. So we’ve seen improvements in technology on the grid that get triggered by these events, and then work to protect the different assets.”

Grid operators can also respond in lower tech ways, such as by deferring maintenance or taking systems offline. And to be clear, if there are any grid effects, those will happen just to long-distance transmission lines. Transformers and any wires connecting to your house should be totally fine.

Will the solar storm affect solar panels? According to NOAA, any panels here on Earth should be totally fine since they’re protected by the planet’s atmosphere. Solar panels in space, e.g. those powering satellites, are at more risk depending on the height of their orbit, particularly if they’re outside the reach of the Earth’s magnet field.

The magnetic field will also determine how bad the storm gets here. Earth’s magnetic field points northward. (That’s why compasses work.) If the the solar storm’s magnetic field is oriented in the same direction, its effects will be dampened. “Think of a magnet,” said Shawn Dahl, another of NOAA’s space weather forecasters. “If you take two negative magnets and you try to put them together, they don’t connect, right? Same thing here.” That magnetic orientation can change in the course of a single storm, however, and if suddenly those two poles start drawing together, the effects can intensify.

As of now, NOAA has classified the situation as a severe geomagnetic storm — G4, on a scale that goes up to G5 — of which several have hit Earth since 2005, including one in late March. Those were weaker than the one barreling toward us at the moment, however, although we won’t know how severe this one will be until it passes satellites stationed about a million miles out in space — that is, at most 45 minutes before it hits.

So, is NOAA concerned? “Yeah, we’re a little concerned,” Dahl said, adding that in addition to coordinating with utilities and other operators of critical infrastructure, NOAA is also briefing the Federal Emergency Management Agency. GPS and other satellite-dependent technologies could experience disruptions. Will those be debilitating to society? Probably not.

There’s also one big upside: “The biggest manifestation of space weather is the aurora,” Steenburgh said, a.k.a. the Northern Lights, which could be visible as far south as Alabama. Even if you can’t see anything with the naked eye, it’s worth pointing your cell phone at the sky and snapping a pic, said Brent Gordon, another NOAA space scientist.

“Cell phones are much better than our eyes and capturing light,” Gordon explained. “Just just go out your back door and take a picture with a newer cellphone and you'd be amazed at what is what you see in that picture versus what you see with your eyes.”

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