Eversource and National Grid have successfully completed the Ready Path Solution ahead of schedule, as part of their collaboration to enhance the reliability of the region's electric system in preparation for the expected retirement of the Mystic Generating Station.
“Our partnership to complete this project ahead of schedule is an important step forward for upgrading regional transmission infrastructure, which is the backbone of the electric grid and critical to achieving decarbonization and electrification goals in Massachusetts,” said Bill Quinlan, Eversource President of Transmission and Offshore Wind Projects. “Supporting the retirement of the fossil fuel-fired Mystic Generating Station, the Ready Path Solution will save customers millions of dollars each year and facilitate a cleaner and more resilient grid.”
The Ready Path Solution was chosen by ISO New England (ISO-NE), the independent power grid manager, as the most cost-effective option to maintain grid reliability after the 2,000 MW Mystic Generating Station shuts down. It was competitively selected from several alternatives and has an installed cost of $49 million.
Without upgrades to the electric grid, the closure of the Mystic Generating Station would pose reliability risks for customers in the Boston area, including overloaded transmission lines and system instability, according to ISO-NE. To address this, Eversource and National Grid implemented the project within their existing substations located in Cambridge, Haverhill, Amesbury, and Tewksbury.
In 2022, National Grid upgraded the control systems at the Amesbury and Haverhill substations, ensuring reliable response and preventing transmission line overloads. Eversource also enhanced power flow efficiency by installing equipment at its North Cambridge substation.
The final component of the Ready Path Solution, a Static Synchronous Compensator (STATCOM), was installed by National Grid at its Tewksbury substation. This equipment provides voltage support and reactive power control to the transmission network. With the completion of this installation, the entire project was put into service on June 7, 2023.
The collaborative efforts between Eversource and National Grid guarantee reliable service for customers across the region, while avoiding the estimated annual expense of $175 million to keep the Mystic Generating Station available for system reliability purposes.