By David Jwanier
After several months of evaluation, PJM is close to naming a developer to fix the Artificial Island transmission stability problem, with LS Power’s proposal for an overhead crossing of the Delaware River holding on as the lowest-cost choice.
PJM’s Paul McGlynn told the Transmission Expansion Advisory Committee last week that the RTO will schedule a special meeting shortly — preferably before the next TEAC meeting May 8 — to discuss its evaluations of the proposals in detail. PJM expects to recommend a winner to the Board of Managers in July.
The presentation to the TEAC listed 10 apparent finalists among the 26 proposals submitted in July, including five that would add a 17-mile 500-kV line that parallels an existing 500-kV line from Red Lion to Hope Creek.
Five other proposals would cross the Delaware River to the Delmarva Peninsula south of Artificial Island with a 230-kV line and run to a new or expanded substation. Three of the proposals would run a submerged line in the river bed and two others would run the line above the water.
McGlynn said PJM planners and the RTO’s engineering consultant concluded that they needed to add options that increased the proposals’ price tags by as much as $192 million. The additional costs included an additional cable for the submarine crossings and an auto-transformer to proposals that included only one bank.
LS Power’s overhead proposal, the lowest cost proposal by its own estimate, remained the cheapest in PJM’s recalculation.
Dominion’s overhead proposal tumbled from second to fifth as PJM added $125 million in costs, nearly doubling its price tag. The Pepco Holdings/Exelon proposal received the biggest boost in the relative rankings, rising from sixth to second even as PJM added $59 million in costs.
PSEG’s cost estimate was the only one reduced by PJM’s calculations, though its ranking rose only from 10th to seventh.
The review estimated all of the projects would take about two years to build. For the Southern Delaware crossing proposals, it identified obtaining permits for the river crossing and crossing Delaware Route 9, a “Scenic and Historic Highway,” among the chief scheduling risks.
The Red Lion proposals face challenges including coordinating with the Salem and Hope Creek nuclear plants and the need to take out of service line 5015, which has had no more than an eight-day outage in the last 15 years.
Stakeholders have raised several technical questions about the proposals, including directional carrier blocking (DCB) schemes and the performance of static VAR compensators (SVCs).
Esam Khadr of PSE&G questioned the security of using DCB schemes and reliability of using SVCs.
“There are 3,800 MW of generation at Artificial Island. If the SVCs fail to respond to a severe disturbance, it could lead to unit instability [at Artificial Island] and a loss of the electrical system,” he said.
Steve Herling, vice president of planning, said planners will conduct market efficiency studies on the proposals before selecting a winner, but that they are unlikely to have a major impact because there is little congestion in the area.