Connecticut Light & Power's new substation in Westport is probably overlooked by many drivers and rail commuters ... and that is exactly what CL&P executives want.
Standing on a 2.5-acre lot across New Creek Road from the Greens Farms Metro-North train station, CL&P's "18P" substation is buffered from public view by about 160 evergreen and deciduous trees, plus about 30 viburnum and rhododendrum shrubs.
"The design was intended to do as much screening as possible to keep the public from having to look at it," said Chris Swan, CL&P's director of municipal relations and siting.
The unobtrusive appearance of the greenery belies the importance of the infrastructure behind the verdant facade. At the New Creek Road site, CL&P built during the last two years a $19.6 million substation designed to be a critical element of the utility's delivery system of electricity to thousands of Westport residents. And, in a town wracked last year by a tropical storm and a nor'easter that each knocked out power to thousands of residents for days at a time, 18P could also act as a bulwark against future mass outages.
How it works
The substation has a few crucial features. It houses two circuit breakers and two transformers, which make the substation easier to operate and allow it to draw power from transmission lines tied to towering monopoles alongside Metro-North Railroad's New Haven line. Those lines carry electricity from power plants in Norwalk and Bridgeport.
"One of the reasons that this site was chosen, that made it so strategic to us, is that it's close to the transmission lines," said CL&P senior communications specialist Frank Poirot. "This substation taps right into those transmission lines that are energized at 115,000 volts."
Electricity can arrive at the substation via the transmission lines from either direction -- a setup analogous to two exit ramps on a highway, one for northbound traffic, the other for southbound vehicles. Power passes from a bus on a steel frame into one of the substation's two large transformers, which trim the 115,000-volt current from the transmission lines down to 13,800 volts. The stepped-down electricity then exits the substation and moves into CL&P's street distribution system, before finally coursing into the homes and offices of CL&P customers.
Fiber-optic cable will link the substation to a CL&P control center in Berlin, allowing remote monitoring. CL&P employees will also make weekly site visits to 18P.
The substation will begin serving CL&P customers with two circuits by November. During its first year of operation, 18P will then expand its output with the introduction of five more circuits, which will bring the substation's total of circuits to seven. Eventually, 18P will serve about 5,000 customers, or approximately 40 percent of CL&P's users in Westport.
"There's a growing demand in the town for electricity," Poirot said. "It's growing at about 1.5 percent [in kilowatt hours] per year."
With a capacity of 90 megawatts, 18P will be CL&P's largest substation in Westport. In comparison, its substation on Compo Road South between Interstate 95 and the Metro-North line has a capacity of 55 megawatts and its substation adjacent to the Ace hardware store on Main Street has a total output of about 19 megawatts.
The 18P service area will extend south to north from Long Island Sound to Coleytown Road, and west to east from Hillspoint Road and Roseville Road to Westport's border with Fairfield.
Despite its proximity to the Metro-North line, 18P will not supply electricity to the railroad. While Metro-North uses CL&P's transmission system to supply power to its trains, it buys its electricity wholesale on the open market.
While CL&P has planned and built 18P, it has operated a temporary substation, 51R, which stands a few hundred yards away from 18P on Clayton Street, a side street near the Greens Farms station. Serving about 1,000 customers, the temporary substation has helped to reduce the load on CL&P's main substation in southeast Westport. Built in 1956, that 25-megawatt facility stands next to Arby's and the former site of the J. McLaughlin clothing store on Post Road East.
CL&P plans to take 51R out of service by the end of 2012, according to Poirot and Swan.
The summer, when many CL&P customers crank up their air-conditioning systems, represents the most testing time for CL&P's Westport substations.
"You look at normal usage and add 500 to 1,000 megawatts on to that system," Poirot said. "It's all attributable to air conditioning. This station will give us a tremendous amount of margin to continue to serve customers during high-heat, high-humidity periods of the year."
The need to update its infrastructure to accommodate escalating demand in Westport is not a new concern for CL&P executives. In February 2006, Swan met with First Selectman Gordon Joseloff to inform him that CL&P planned to build a new substation to serve its Westport customers. A few months later, the temporary substation on Clayton Street went into service.
In 2008, CL&P acquired the 18P site on New Creek Road and later tore down the single-family home that stood on the property.
CL&P applied to the state's Siting Council in December 2009 to build the substation and received approval in May 2010. Construction of 18P started in September 2010 and finished last April.
While CL&P did not need to secure approval from Westport government boards, it, nonetheless, sought to garner support from town officials and neighbors of the substation, Swan and Poirot said.
"A lot of the town's thinking and a lot of the neighbors' thinking is reflected in the final design of this substation," Poirot said. "We were able to meet our electrical needs of serving customers here and at the same time meet the neighborhood's needs for maintaining its aesthetic beauty down here."
The Greens Farms Association has been one of the most influential citizen groups during the planning and building of the substation, offering input to CL&P on traffic, safety and landscaping issues related to the new complex.
"At some point, there was going to be a [new substation] site somewhere in Westport, and more than likely it was going to be somewhere in Greens Farms," said Greens Farms Association President Art Schoeller. "It's going to help in terms of giving some alternate routing and alternate power."
The substation will also provide another boon to Westport. It construction substantially raises the assessed value of the New Creek Road property, which will generate more tax revenue for the town. CL&P already ranks as the No. 1 taxpayer in Westport.
Weathering the next big storm
When Tropical Storm Irene blacked out much of Westport a little over a year ago, 18P was still under construction. Once it is operational, CL&P executives hope the new substation will help to mitigate power disruptions inflicted by future storms.
If its power supply is cut off, 18P can run on batteries stored in its control house. It will also be expected to handle additional capacity if another substation is stricken, for instance, by a lightning strike. New lightning-protection technology will also bolster 18P's storm defense.
"It'll immediately give you more flexibility, more strength and more options during big storms," Swan added. "The net effect -- not that it's going to guarantee that everyone won't lose power -- but it'll certainly give you a much stronger operating system."
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