Developing an actionable EMP/GMD hardening program for an electric utility

Two electromagnetic threats to the electric grid, which have drawn recent attention, are the Electromagnetic Pulse (EMP) and the Geomagnetic Disturbance (GMD). Both are considered High Impact Low Frequency (HILF) events where the probability of occurrence is unknown and thought to be low, while the potential consequences are thought to be high. This produces a situation in which rationally deciding on what actions should be taken to protect against the threats is difficult. This paper describes an approach being taken at one electric utility to develop a rational program for EMP/GMD hardening of critical utility assets.