FERC greenlights grid defense proposal against solar storms

Source: Peter Behr, E&E News reporter • Posted: Monday, May 21, 2018

The Federal Energy Regulatory Commission last week unanimously agreed to proceed with a proposed second phase of its rules requiring operators of high-voltage power systems to protect equipment against a once-in-a-century solar flare, whose rogue currents could cause major blackouts and destroy transformers.

The commission gave the industry 60 days to respond before it takes final action.

FERC acted on a proposed rule drafted by the North American Electric Reliability Corp. and approved by its industry members. “Action to address geomagnetic disturbances (GMDs) is critical,” Commissioner Neil Chatterjee said, referring to the damaging electrical currents on Earth spawned by the sun’s largest magnetic energy pulses.

“Because it’s not a question of whether we’re going to experience a serious geomagnetic disturbance; it’s a question of when,” Chatterjee said.

Chatterjee said he appreciates the continuing research challenges surrounding the threat but added, “Given the potentially catastrophic consequences of a severe GMD event, I think it’s prudent to err on the side of action rather than inaction.”

The commission action gives NERC, its appointed grid reliability overseer, 12 months to complete several additional requirements. The timetable for industry response to the principal Phase II requirements was not changed.

NERC’s updated timetable suggests that some scientific investigations on the threat would not be completed until 2020, while others would be finished earlier. The research includes complex calculations of how the GMD current strengths would vary depending on the location of grid equipment and rock and soil conditions affecting current movements.

NERC’s plan would give utilities one year to turn the research findings to action plans, with two more years to comply with changes in non-hardware equipment. Utilities would have four years from planning to completion to make changes to transformers and other hardware. Yesterday, FERC directed NERC to add several features including studies of localized impacts from GMDs.

“This is a journey we’ve been on,” Commissioner Cheryl LaFleur said at a conference earlier this year, pointing back to the commission’s initial work. “Since 2010, we’ve been working on this.”

In May 2013, the commission directed NERC to develop standards on the GMD threat and its impact. Phase I of the regulation required covered transmission utilities to create operating plans that would prevent cascading blackouts. It required strategies that could include putting parts of the grid in a “safe” mode, starting up generators closer to cities to reduce distances that power travels on high-voltage lines, or even blacking out parts of the United States threatened by the storm.

LaFleur noted that warnings from satellite measures of the solar blast could give grid operators about 20 minutes to take action.

“We need to increase that public awareness so that people understand that a severe [solar] storm is coming,” Steven Clarke, the director for heliophysics at NASA, heading research on solar impacts to Earth and the solar system, said in a 2016 interview.

He added, “There are certain steps we need to take including planned blackouts to save transformers and the grid, and people will be without power for some time until the storm subsides.”

‘Slow wave’

The Phase II order would direct grid operators to develop strategies that don’t require dropping customers to protect equipment.

In January 2015, NERC submitted its Phase II proposal. The commission gave the plan partial approval in Order 830, in September 2016, saying the commission action “constitutes an important step in addressing the risks posed by GMD event,” but ordered NERC to make modifications to clarify assessments of GMD risks. And FERC sent NERC back to make further changes on one narrower issue involving local impacts of the solar storms.

Michael Howard, head of the Electric Power Research Institute, told state regulators this year that the energy from solar storms, which resembles low-voltage direct current, “can cause transformers to overheat; it can cause hot spots in transformers; it can cause difficulty in maintaining voltage stability on the transmission system.”

Howard said EPRI research on an electromagnetic pulse’s “slow” wave, similar to a GMD, shows that it would cause regional blackouts, but that destruction of transformers would be minimal. Other experts have challenged that conclusion.

“That’s what a GMD could result in,” Howard said. He said research at EPRI and Energy Department labs has made great headway.

“We’re starting to understand more about it and take steps to prevent that from occurring,” Howard said. “Fortunately, it doesn’t happen very often.”

The last major solar-caused outage was the blackout of the entirety of Quebec in 1989, when a solar storm led to a voltage collapse in 90 seconds. The “once in a century” storm, named for the British astronomer Richard Carrington, who measured it, hit North America in 1859. It took down parts of the telegraph network and produced an aurora display visible in Cuba. That was 159 years ago.

At a 2015 conference, Daniel Baker, a professor of planetary and space physics at the University of Colorado, Boulder, stressed that what is still not known is the most alarming issue.

He related how a massive solar pulse from such a once-in-a-century solar storm narrowly missed Earth in 2012.

“We’d probably still be picking up the pieces if that event had occurred a week earlier,” Baker said.