Faced with a cranky 1930s substation in need of service, two TVA employees get creative about how to keep power flowing so repairs can happen.
JULY 11, 2018—What do you do when your mission is to keep the lights on, but a 1930s substation that provides power to approximately 1,000 people must be out of service for several months? If you are electrician Jonathan McCullough or line foreman Roy Arms, you get creative.
Ingenuity was required to meet the unique challenge of a single transformer substation that was connected by only one line coming over the mountain. Substations usually have more than one transformer, so a substation can take one transformer out of service while the other is being worked on—keeping the overall substation operational. “There was no means of bypassing the substation without putting Sherwood and Anderson in the dark, and that wasn’t an option,” says McCullough.
On May 20, McCullough of Murfreesboro, Tenn., and Arms of Winchester, Tenn., coordinated the successful transfer of power from the Sherwood Substation to a mobile substation that was mounted on a trailer—a design idea that McCullough scratched out on a piece of paper and began building just two months before. His solution allowed the dated Sherwood transformer to be taken out of service for refurbishing, while the mobile substation continues to maintain power to the remote Tennessee communities of Sherwood and Anderson, just a few miles south of Sewanee.
“I sort of like projects that people say can’t be done, but this was a stretch for me.” McCullough says. “Luckily, everybody I ran into was extremely helpful.” While McCullough planned with TVA engineers, electricians, Duck River Electric Membership Corporation staff, Transmission Operations and the Finance staff in Chattanooga, Arms began creating a plan to make McCullough’s mobile substation operational. Arms and his team of linemen would have to build the infrastructure that would allow the Sherwood Substation to be bypassed and the mobile substation to be energized—a task that would eventually involve even the cooperation of the CSX railroad.
“We were in close coordination with CSX railroad to meet the challenge of pulling new lines across the railroad tracks. When a train was scheduled to pass the crew had to stop work”, says Arms.
Ultimately, the midnight outage that was to take eight hours was completed in only four hours.
“I can’t begin to describe the hard work, time and dedication Jonathan and Roy put into this project to ensure reliability to Duck River customers,” says Jason Baggett, Transmission Service manager of Murfreesboro. “Both went above and beyond the role of lineman and electrician.”
Arms attributes the successful outcome to the teamwork and comradery among the many organizations involved.
“It’s the way outages are supposed to work; I couldn’t have asked for anything better,” Arms says. “That night we were just a ‘Band of Brothers’ working together.”
TVA is investing $600,000 in the Sherwood overhaul including the mobile substation which can be reused in the future. Work begins in about a month and the substation is planned to be back in service, with improved reliability, in fall of 2018.