Oak Ridge, Tenn.— Y-12 flipped the switch on a new era as crews finalized the process of moving the entire site’s electrical supply to the new Pine Ridge substation.
In June, the Building 9204-02 (Beta 2) and Building 9201-01 (Alpha 1) electrical feeds were disconnected from the Elza-1 substation, marking the final load transition to Pine Ridge.
The new substation was constructed as one of seven Uranium Processing Facility (UPF) Project subprojects. Designed and built by the Tennessee Valley Authority (TVA), Pine Ridge substation construction began in 2017 and was completed in 2020 at a cost of $60 million. The project team received the U.S. Department of Energy (DOE) Secretary’s Project Management Achievement Award for finishing $13 million under budget and six months ahead of schedule. It is a 70-MVA (mega volt amp) facility and includes:
• 161-kilovolt (kv) switchyard,
• 13.8-kv power transformers,
• TVA switch house,
• DOE/National Nuclear Security Administration (NNSA) power distribution center, and
• 161-kv transmission lines.
New substation will serve Y-12, UPF
The Pine Ridge substation now fully services both Y-12 and the UPF project. UPF is one of DOE’s largest construction projects and investments in Tennessee since the Manhattan Project.
“This is a huge win for Y-12,” said Tim Hutson, director of Y-12 Utilities Management. “It positions us well, from an electrical distribution perspective, to serve the people and the mission of Y-12 for the next two to three decades.”
The original Elza-1 was completed in 1952. Then, it was responsible for providing uninterrupted power to operate the site. As the main power feed for Y-12, it was rebuilt in the 1990s.
“The Elza-1 substation was oversized for the current Y-12 mission,” Hutson said. “Elza-1 is a 300‑MVA substation. Pine Ridge is 70 MVA.”
The smaller substation is a win-win for the site, according to Hutson. “In addition to cost- and risk-reduction advantages, there is an approximate $30 million reduction in deferred costs, as well as significant decreased environmental and safety risks.”
End of an era approaching
The final phase of the transition is quickly approaching.
“We can see the end of this effort in the next few months,” Hutson said. “This will mark the end of an era for the Elza-1 substation. It will be cold and dark by October, when TVA begins the process of transitioning the Bull Run feed from Elza-1 to Pine Ridge.”
“Looking back, this has been a huge effort,” Hutson said. “It has taken a lot of people to make this happen, involving multiple organizations including Mission Engineering, the Project organization, our subcontract partners, federal customers, the UPF project, and TVA. This has been an exciting time.”