Sunday, August 7, 2011

As Sun Storms Ramp Up, Electric Grid Braces for Impact

Storms are brewing about 93 million miles (150 million kilometers) away, and if one of them reaches Earth, it could knock out communications, scramble GPS, and leave thousands without power for weeks to months.

The tempest is what's known as a solar storm, a flurry of charged particles that erupts from the sun. Under the right conditions, solar storms can create extra electrical currents in Earth's magnetosphere—the region around the planet controlled by our magnetic field.

The electrical power grid is particularly vulnerable to these extra currents, which can infiltrate high-voltage transmission lines, causing transformers to overheat and possibly burn out.

"The concern is if the electric grid lost a number of transformers during a single storm, replacing them would be difficult and time-consuming," said Rich Lordan, senior technical executive for power delivery and utilization at the Electric Power Research Institute (EPRI).

"These power transformers are very big devices, and the lead time to get a replacement can be two months—if there's a spare one stored nearby. If a utility has to order a new one from the manufacturer, it could take six months to up to two years to deliver."

The danger is becoming more critical, as the sun is approaching what's known as solar maximum—the high point in our star's roughly 11-year cycle of activity. Scientists anticipate stronger storms around solar max, in 2013. (more)