CMP Building New Type of Smart Grid Facility in Westbrook

B/ROLL

For the first time, CMP is building a compact version of a fully-enclosed switching station in its service area using pre-built components trucked to a work site.

Westbrook, ME - October 6, 2025 - Central Maine Power (CMP), a subsidiary of Avangrid Inc., today announced it has reached a key phase in its project to build a new "switching station" at the Rock Row site in Westbrook.

Beginning on September 5, special construction vehicles and a large crane were used to deliver and set in place three large smart switching modules that are now being fully installed and integrated as one unit into the CMP grid. Together, these pre-built modules will function as one switching station, adding significant efficiency to the construction timeline for this project that benefits thousands of customers served by CMP transmission lines in Westbrook and Portland.

Transmission lines are part of the "backbone" of Maine's energy grid that bring power to large numbers of homes and businesses. Unlike a substation, a switching station does not affect power voltage but acts as a central location for operating and monitoring the grid remotely using smart technology that was pre-installed into the station's modules offsite.

This has specific benefits during extreme weather and storms. The new compact gas-insulated switchgear (GIS) in this facility serves as a point where multiple transmission lines in these communities "link" together. In the event one line is damaged due to an extreme storm, smart technology operated remotely by staff in CMP's Energy Control Center can "move" customers from one line to another. This provides a backup route for power to flow to customers with minimal disruption.

"Compact GIS facilities are a great example of 21st century infrastructure that can be specialized for uses in ways that weren't previously possible," said Eric Sutton, Vice President of Electric Operations for Central Maine Power. "Pre-installing smart technology into strong, weatherproof enclosures before the enclosures are moved onsite allows us to address grid reliability needs in areas that are space constrained. This type of construction also accelerates project timelines and improves efficiency for our crews as they perform work."

The enclosures at this site also help protect animals from coming into contact with electrical equipment. This is similar to CMP's other recently-built GIS substations in locations like Scarborough and Wilton. News media may download rights-free video of the Sept. 5, 2025 crane work at this facility HERE.