HERSHEY, Pa. — Planners seeking to protect the grid against physical threats should consider transmission alternatives as well as security measures, Mike Kormos, PJM executive vice president for operations, told a conference of state regulators last week.

“You can only harden a substation so much. If someone wants to attack a substation, they will,” Kormos said during a panel discussion at the Mid-Atlantic Conference of Regulatory Utilities Commissioners’ (MACRUC) annual education conference here. “That leads us to the resilience piece. Maybe the best way to make a substation less critical is to build more transmission. A substation is critical basically because we’re pushing too much power through it.”

Kormos said most of PJM avoided the cascading 2003 blackout largely because it had “headroom” — excess capacity — in its system. “It wasn’t operations [that saved PJM]. It happened too fast. It was good planning.”

Kormos said PJM will start ranking its substations by criticality to target needed spending. PJM has begun discussing with state regulators and the Federal Energy Regulatory Commission how it can balance confidentiality concerns with the need for cost oversight and the transparency of the Regional Transmission Expansion Plan (RTEP).

Kormos said PJM will publicly share its criteria for determining criticality “so people are comfortable we’re not simply gold plating the system for the sake of … returns.” The challenge, he said, is creating a process that allows state regulators to validate the need for security spending while “not going so far as putting out a map and putting a big ‘X’ and saying, ‘Plant the bomb here.’”

Transformers’ Vulnerability

Transformers are a tempting target because they are expensive and time-consuming to replace, requiring a lead time of five to 12 months from U.S. manufacturers and six to 16 months from foreign suppliers, according to a newly released congressional report.

Substations containing transformers are easy to identify and generally unguarded, unlike other critical facilities such as generating stations or control rooms.

At a cost of $2 million (230 kV) to $7.5 million (765 kV) — excluding transportation and installation — maintaining a large inventory of spare high-voltage transformers “is prohibitively costly,” the Congressional Research Service report noted.  (See related story, Report: Uncertainty over Sabotage Threat Could Lead to Wasteful Spending.)

In 2006, the Edison Electric Institute (EEI) began a Spare Transformer Equipment Program (STEP) to enable the grid to restore operations quickly following a terrorist attack. The program requires participating utilities to maintain a specific number of transformers up to 500 kV to be made available to other utilities in an emergency.

Although the number of spares that grid operators keep on hand is closely guarded, a 2007 news report cited in the congressional study said that PJM maintained 29 spares for 188 transformers on its system rated at 500 kV.

PJM may be better off than some regions, having standardized 500-to-230-kV transformers several years ago, according to Kormos. There are two standard designs, one for the Dominion zone another for the rest of the RTO.