FERC has approved a new Reliability Standard to address Geomagnetic Disturbances (GMDs). EOP-010-1 (Geomagnetic Disturbance Operations) is the first in a set of Reliability Standards addressing the threat of GMDs to bulk-power system reliability. FERC’s concern with GMDs has been that they can create geomagnetically induced currents in transformers, which can, in turn, increase the absorption of reactive power, create harmonics, and cause transformer spot-heating. Ultimately, the loss of reactive power this causes could result in voltage instability, relay misoperations, and equipment damage.

As written, the new standard applies to (a) Transmission Operators whose Transmission Operator Area includes a power transformer with a high side, wye-grounded winding with terminal voltage greater than 200 kV and (b) Reliability Coordinators.

Among other requirements in the new standard, applicable Transmission Operators must develop and implement operating procedures or processes to mitigate GMD effects. Those procedures and processes must specify (a) the steps that each Transmission Operator will follow to receive space weather information, (b) the actions that they will take under identified GMD conditions, and (c) the conditions under which the processes or procedures would be terminated following a GMD condition.

In its order, FERC concluded that the applicability of the standard was appropriate and that this Standard is a sufficient first step in addressing FERC’s initial directives on GMDs in Order No. 779.

The new standard will become effective on the first day of the first calendar quarter six months after the effective date of FERC’s order.