Protecting critical substations is an expensive and difficult proposition given locations and topography, and the answer may lie in a Design Basis Threat approach.
Recent history has given rise to an almost feverish obsession with regard to thinking about “grid security” and large-scale national or regional cascading events. Ever since the Metcalf Substation attack of 2013, regulators, utilities and Congress have been almost single mindedly focused on just such an event — a large scale, multi-jurisdictional, simultaneously coordinated attack against numerous substations critical to interconnections. In these scenarios, an adversary would need to damage and disrupt the substations in question, in particular the extra high voltage (EHV) transformers, in order to trigger a regional to national cascading outage. Under this premise, the theory holds that the affected region, and by extrapolation nation, would be operating without, or with reduced power for months or possibly even years. The premise of such an attack is complicated, and not without strategic and logistical constraints — not the least of which is the adversary being able to accurately predict the correct timing (weather conditions), load, and correct substations to attack to accomplish a cascading event. Identifying and defining such a list is a difficulty that has not been lost on either the Government or utilities as true modeling for such an event is complicated and relies on numerous assumptions. Further complicating this effort has been the lack of trust between utilities and the Government after the ill-fated “critical substation” list was allegedly leaked by government regulators.
Even more troubling is the fact that some private actors have created and compiled their own “critical substations list” utilizing different methodologies to analyze open source information. For those that have seen the subscription service’s report, it is a point-by-point analysis of how to attack the identified substations — right down to asset owner, photos, and longitude and latitude identification. The accuracy and feasibility of the report is open for debate amongst transmission engineers but the point remains — information is out there.