FERC official testifies on electromagnetic pulses and geomagnetic disturbances

Electromagnetic pulse and geomagnetic disturbance events "pose a serious threat to the electric grid and its supporting infrastructures that serve our Nation," according to testimony delivered by a federal official to the U.S. Senate Committee on Homeland Security and Governmental Affairs.

Electromagnetic pulse (EMP) and geomagnetic disturbance (GMD) events are two types of events that could affect the nation's electric grid. Generally speaking, GMD events are naturally occurring solar magnetic disturbances which periodically disrupt the earth’s magnetic field. These disruptions can induce currents on the electric grid that may simultaneously damage or destroy key transformers over a large geographic area.

On February 27, 2019, Joseph McClellan, director of the Federal Energy Regulatory Commission's Office of Energy Infrastructure Security, testified before the Senate committee. As described in his testimony, EMP events can be generated by "devices that range from small, portable, easily concealed battery-powered units all the way through missiles equipped with nuclear warheads." High-altitude nuclear detonations can generate three distinct EMP effects: "a short high energy radio-frequency-type burst called E1 that can destroy electronics; a slightly longer burst that is similar to lightning termed E2; and a final effect termed E3 that is similar in character and effect to GMD, with the potential to damage transformers and other electrical equipment."

According to Director McClellan's testimony, any of these effects could lead to "wide-area blackouts." In his testimony, he cited reports by the federal EMP Commission as finding that "a single EMP attack could seriously degrade or shut down a large part of the electric power grid," with the potential that significant parts of electric infrastructure could be “out of service for periods measured in months to a year or more."

He also cited a 2010 study by Oak Ridge National Laboratory as finding that "EMP and GMD events pose substantial risk to equipment and operation of the Nation’s electric grid and under extreme conditions could result in major long-term electrical outages," that "GMD disturbances are inevitable with only the timing and magnitude subject to variability," and that a solar storm such as occurred in 1921 "could damage or destroy over 300 bulk power system transformers interrupting service to 130 million people with some outages lasting for a period of years." Director McClellan clarified that subsequent analysis suggested that in case of such an event, "the power grid may collapse before significant damage was done to transformers; resulting in a potentially wide-spread, but relatively short, power outage."

Director McClellan also spoke to the Federal Energy Regulatory Commission's "dual-fold approach" to address these threats: employing mandatory standards to establish foundational practices while also working collaboratively with industry, the states and federal agencies to identify and promote best practices to mitigate advanced threats. According to a report released in 2018 by the U.S. Government Accountability Office, U.S. and Canadian electricity suppliers have taken steps to prepare for potential electromagnetic disruptions, but more research is needed on both geomagnetic disturbances and high-altitude electromagnetic pulses.