The Challenge

The existing 345-kV transmission line from Rhode Island is a key component of the east-west transfer of power in New England. The biggest challenge for the NECTR project team was planning and preparing for the scheduled power outages that were required to complete critical portions of the work. These outages had the potential to affect CL&P's customers and adjacent power generators, so it was the project team's stated objective to limit both the number and duration of the required outages. Scheduling transmission-system outages requires the coordination and cooperation of many parties — including the Connecticut Valley Electric Exchange (CONVEX) and ISO-New England — as well as managing the work-around design, engineering and construction to support them.

The NECTR project got under way in early 2004, beginning with NU's planning, financial and technical approval, preliminary engineering, and municipal siting/permitting phases. The project received Connecticut Siting Council approval in May 2005.

MJE's EPC project team began fast-tracking the detailed engineering and procurement activities in October 2005. Site preparation and rough grading quickly followed in December 2005. MJE's electrical construction team then began, in earnest, during April 2006.

The Killingly substation was energized and put in service on Dec. 16, 2006. This major undertaking was brought in on time and under budget by the NU and MJE project teams. Coming in under budget required the complete and concise up-front definition of the project's technical scope — as well as a clear understanding of the scope's limits — while also maintaining cost and schedule vigilance.

Constant vigilance of the project's critical path schedule was the key to keeping the project team on track toward a successful completion of necessary tasks and the coordination involved with these outages. This vigilance also helped to identify, manage and mitigate risk while minimizing potential service disruptions.

The Success

It was the objective of the project team to limit both the number and duration of the required outages. To that end, the project team also used an innovative design and construction approach.

They planned for two short-duration outages to cut in the 345-kV side of the new substation. The first, a spring outage of seven days was used to erect and place into service two new 345-kV transmission towers and two new 345-kV substation terminal structures. These structures helped raise the overhead 345-kV transmission line that increased the working clearances for both the workers and the large equipment being used, and to facilitate ongoing construction activities for the substation throughout the summer months. After all construction and acceptance testing activities were completed in the fall, another outage of five days was required to cut in the 345-kV side of the new Killingly substation.

Consistent with NU's emphasis on workplace safety and environmental stewardship, this complex project — including 50,000 hours of construction, testing and commissioning activities — was completed with a stellar safety record and no environmental compliance issues. A success by any standard, the NECTR project's crowning achievement is the end result: a vastly improved energy infrastructure with reliability and load capacity that eastern Connecticut can count on, now and in the future.

Jim Clark has been supporting Northeast Utilities Transmission as a project manager since 2005. He came to Northeast Utilities after nearly 20 years in project management and project engineering with ABB Utility Automation and ABB Impell. Clark is a graduate of the United States Merchant Marine Academy in Kings Point, New York, U.S., where he earned a bachelor's degree with honors in marine engineering systems. Clark is a registered professional engineer in the state of New York and a certified project management professional.
clarkxx@nu.com

Focus on Reliability

The scope of the Northeast Connecticut Reliability project was wide. The following is a breakdown of all the tasks that had to be done to make the project a success:

• Build the new Killingly bulk-power substation with a new 345-kV/115-kV autotransformer on existing CL&P property in Killingly and Putnam, Connecticut
• Loop the existing 345-kV interstate transmission line (Sherman Road, Rhode Island, to Lake Road, Connecticut) through the new substation
• Loop the two existing 115-kV transmission power lines (Tunnel substation to Tracy substation) through the new substation
• Provide transmission-system protection and control (P&C) additions at Killingly, as well as P&C upgrades at four existing substations: Tracy, Lake Road, Frybrook and Tunnel
• Add an additional 345-kV circuit breaker at the existing Card Street substation, along with required P&C upgrades
• Install fiber-optic communications (P&C) between the Tracy, Killingly and Lake Road substations
• Upgrade the existing 115-kV terminals at the Tracy and Tunnel substations.