Vermont Tested Power Flow Tech to Shield Transformers
A DOE-funded grid project aims to stabilize regional transmission by reducing mechanical wear on legacy hardware.
Updated on Oct. 12, 2026 in Energy
Live Poll
Do you trust that new digital grid technology improves power reliability more than traditional mechanical equipment?
In mid-2025, partners launched a demonstration project to install power flow control technology at Vermont's Sandbar Station. This effort follows a 2021 Phase Shifting Transformer failure and focuses on mitigating mechanical stress on the grid.
Why it matters
The project addresses critical grid stability concerns caused by volatile power flows between Vermont and New York. By reducing mechanical wear, this approach offers an alternative to traditional transformer management as regional energy demands increase.
The project involves installing 12 SmartValve modules to regulate transmission paths, compared to the mechanical-only control previously handled by the failed Phase Shifting Transformer. The modules use power electronics to dynamically adjust electrical characteristics.
The players
Electric Power Research Institute (EPRI)
A non-profit research consortium that conducts collaborative R&D for the electricity sector.
Vermont Electric Power Company (VELCO)
The operator of Vermont's high-voltage transmission system and electrical infrastructure.
Smart Wires
A technology provider specializing in modular power flow control solutions for grid modernization.
Department of Energy (DOE)
The federal agency responsible for funding energy research and grid resilience programs.
The details
The project employs SmartValve technology — a system of power electronics that rapidly injects voltage into a transmission line to alter its impedance. This allows grid operators to steer power flows away from overloaded paths, reducing the mechanical stress that led to the February 2021 transformer failure at Sandbar Station. By augmenting the existing mechanical control of the Phase Shifting Transformer, the system aims to increase total transfer capacity between Vermont and New York.
Timeline
A Phase Shifting Transformer failed at Sandbar Station in February 2021.
The demonstration project officially commenced in mid-2025.
The team completed a Factory Acceptance Test for the first module in August 2026.
Site construction is scheduled for completion in May 2027.
Commissioning and in-service testing are set for late 2027.
The Tech Race
This deployment follows a trend of integrating modular power electronics into aging high-voltage corridors to bypass physical transmission constraints. The project aims to bridge the gap between fixed mechanical infrastructure and the flexibility required by modern intermittent energy flows.
Residents will not see immediate changes to their utility bills or service, as this is an infrastructure-scale pilot project at the transmission level. The technology serves as a long-term hedge against potential regional power disruptions and transformer failures.
The takeaway
The project serves as a practical test of whether power electronics can effectively extend the life of aging transformers in the face of shifting grid loads. Watch for the 2027 in-service testing results to see if this model scales to other stations experiencing similar mechanical stress.
What happens next
Site construction concludes in May 2027, with full system commissioning and in-service testing expected to follow in late 2027.
Further reading
Learn more about the latest developments in regional power infrastructure within the Energy section.
Source note: This article includes information reported by Energy Central.
Live Poll
Do you trust that new digital grid technology improves power reliability more than traditional mechanical equipment?
