Velco Sandbar Project
VELCO selected SmartValve to protect a critical phase-shifting transformer at Sandbar substation, reducing mechanical wear, adding built-in redundancy, and improving transfer flexibility between Vermont and New York at 16% lower cost than a second PST.
Protecting a critical PST while maintaining transfer control resilience
Changing regional flows were causing excessive tap operations on a critical phase-shifting transformer at Sandbar substation, increasing wear and failure risk on a key Vermont-New York corridor.
Loss of the PST would have reduced transfer flexibility between Vermont and New York and created operational risk during outages and repair cycles. VELCO needed faster, more precise flow control with built-in redundancy, without the cost and lead time of installing a second PST.
VELCO selected SmartValve, an Advanced Power Flow Control solution that provides controllable series compensation operating in series with the existing PST. This enables faster, more precise control while reducing reliance on continuous mechanical tap operations.
The Sandbar project deploys 12 SmartValves at 115 kV, providing 180 MVAr of controllable capability, 50% more power flow control, and 50% redundancy if the PST becomes unavailable. Construction begins spring 2026 with commissioning anticipated summer 2027.
Deployable in half the time
SmartValve can be deployed in half the time it would take to procure and install a second PST, reducing operational risk sooner.
50% redundancy built in
If the PST becomes unavailable, SmartValve keeps the line in service, maintaining transfer control during outages and repair cycles.
Lower cost, faster delivery, and greater resilience
The Sandbar project demonstrates how Advanced Power Flow Control can extend the life of existing grid assets, add redundancy, and improve precision, all at lower cost and on a shorter timeline than conventional alternatives.
Reduced PST tap changes by 60%
Cuts mechanical wear and dramatically lowers the risk of future PST failure, extending the life of the existing asset.
Built-in redundancy
Adds 50% redundancy so the line can remain in service after a PST failure, maintaining transfer control when it matters most.
50% more control capability
Improves transfer flexibility by balancing flows across circuits more precisely, reducing reliance on mechanical tap operations.
Lower cost and faster delivery
16% cost savings versus installing a second PST, and deployable in half the time, reducing operational risk sooner.
Velco Sandbar SmartValve deployment
A look at the Advanced Power Flow Control deployment at Sandbar substation on VELCO's 115 kV network.
Velco Sandbar Project: extending PST life and maintaining power flow control resilience
Access the full case study to learn how VELCO used SmartValve to reduce PST tap changes by 60%, add 50% redundancy, deliver 180 MVAr of controllable capability, and save 16% versus a second PST.
