"QUEBEC CITY — One day, the sun might send a massive explosion of highly charged particles flying directly at North America.

If a storm hits, some U.S. cities could be blacked out until the solar storm passes to protect electric grid transformers threatened by storm currents, grid officials explain.

Those blackouts, coming with less than an hour's warning, could be how Americans first learn about the threat to the power grid from sun-spawned electrical currents called geomagnetic disturbances (GMD).

"This GMD risk, for all intents and purposes, will always be there," said Bob Rutledge, who leads the National Oceanic and Atmospheric Administration's Space Weather Prediction Center, during last week's grid security conference here."

Peter Behr reports for EnergyWire October 24, 2016. [2]