Cable shut down for NGrid repairs
The Block Island Power Company expended 850 gallons of diesel fuel on March 29 while National Grid shut down its sea2shore cable to conduct repairs to a static wire component of its interconnection system. BIPCo President Jeffery Wright said island ratepayers will not be charged for the cost of the diesel fuel.
“We are just going to run that usage through our normal standard offer and transmission rate, and expense the extra cost of the diesel, like we would if it were used for testing purposes,” said Wright, noting that the $300 cost for the diesel fuel will be deemed an operating expense. “The customers won’t see a diesel surcharge on their bills for this limited amount of time.”
National Grid visited Block Island to repair a wire component that was damaged during Winter Storm Riley, which walloped the island with 65 mile-per-hour winds on March 1. The wire is part of National Grid’s interconnection — a conduit for the Block Island Wind Farm to deliver wind-generated energy to BIPCo and its ratepayers after flowing through Grid’s substation. During the work, Grid shut down its 20-mile long sea2shore cable that links the island to the mainland, causing BIPCo to switch to backup diesel generation to power the Island.
Wright said BIPCo switched to backup diesel generation from 7 a.m. until 3:30 p.m., with two 15 minute-long power outages to accommodate the switchover.
He noted that the eight-and-a-half hour cable shut down required BIPCo to expend 100 gallons of diesel fuel per hour.
National Grid’s “work was completed as planned with no issues,” said Wright. “We timed it around the Block Island School’s schedule to minimize the impact to students. The switchover — despite only being our third time — went smoothly and the back up generation did its job well.”
Wright said it was the third time since the Wind Farm was connected to the Island that BIPCo had to switch to, or from, diesel generation. We switched over “once before May 1, 2017 when we cut over for a test, and once on May 1 when we cut over for good, and then yesterday” for the repair work. “The guys are getting pretty good at it,” he said.
Ted Kresse, National Grid’s Director of Strategic Communications, said, “The static wire work was completed smoothly, efficiently and within a few hours. A static wire is sometimes installed above a circuit wire to protect it from lightning strikes. Typically, a static wire wouldn’t ordinarily be used for the type of voltage we have with this system, but we opted for a different approach on the sea2shore project. Given the issues we’ve experienced, we decided to remove the static wire altogether and use a more traditional approach for this type of voltage.”
In the fall, National Grid will return to the island. The sea2shore cable will be shut down to address its shallow burial depth at Fred Benson Town Beach.