By Suzanne Herel

VALLEY FORGE, Pa. — PJM planners said last week they will announce their revised recommendation to address stability problems at the Artificial Island nuclear complex at a special Transmission Expansion Advisory Committee meeting April 28.

Planners recommended Public Service Electric & Gas for the project last June, but the Board of Managers reopened the bidding to finalists Transource Energy, Dominion Resources and LS Power after criticism from environmentalists, New Jersey officials and spurned bidders.

All of the potential solutions involve new transmission lines connecting Artificial Island to Delaware. LS Power and Transource have proposed a southern crossing of the Delaware River. Dominion and PSE&G offered a northern route with an overhead crossing.

Planners had hoped to announce their revised selection in January but delayed their decision to allow consultants to investigate concerns that Dominion’s proposed use of thyristor controlled series compensation (TCSC) could threaten reliability at the island, home to the Salem-Hope Creek nuclear complex. (See Further Study Delays PJM’s Artificial Island Decision.)

PSEG Nuclear, which operates the nuclear plants, contends Dominion’s proposal would use unproven technology that could result in damage to turbine generator shafts.

Planners told TEAC members last week Siemens Power Technology International had completed its sub-synchronous resonance analysis of Dominion’s proposal and found that the TCSC could result in “negative damping” for several resonant frequencies.

However, Exponent, an engineering and science consulting firm that reviewed the Siemens study at PJM’s request, said it was “inconclusive” because of limits in the data available.

Exponent expressed its own concerns with the Dominion proposal. It said Dominion is proposing a 90% post-contingency TCSC compensation — well above the 70 to 80% compensation used by others in the industry.

Responding to questions from stakeholders who suggested more study might be needed to verify the feasibility of the Dominion proposal, Steve Herling, vice president of planning, said Siemens had identified the “potential for an issue.”

“It’s not a fatal flaw,” he said.

“[I]t’s an issue going forward,” said Thomas Leeming, director of transmission operations and planning for Exelon’s Commonwealth Edison. Not “having wrestled this to the ground could be an issue.”

“We understand what needs to be done if we go that way,” Herling responded. “We recognize that if we go with this solution there’s more work to be done. We’ve already talked to a number of manufacturers about all these issues.”

Planners said their current schedule would result in a recommendation to the Board of Managers’ Reliability Committee on May 19.