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Northfield Mountain Pumped Storage Hydroelectricity Facility

Technology Type Open-loop Pumped Hydro Storage
Rated Power 1119000 kW
URL More about Northfield Mountain Pumped Storage Hydroelectricity Facility
Located in Northfield, Massachusetts, approximately five and one-half miles up the Connecticut River from Turners Falls Dam, the 1,080 megawatt plant is entirely underground and does not depend upon the natural flow of the river for operation. Utilizing energy that is generated at nuclear and the more efficient of our fossil plants, water from the lower reservoir is pumped to an upper reservoir during periods of low power demand. The water is stored in the upper reservoir and then, at times of high electric demand, is released down a 1,100-foot-long pressure shaft to power a turbine generator and continues to the lower reservoir where it is stored until it again resumes its cycle to the upper reservoir. The 20-mile stretch of the Connecticut River, extending from the dam at Turners Falls north to the Vernon Dam in Vermont, serves as the station's lower reservoir. The man-made 300-acre upper reservoir, 800 feet above the river, is capable of storing 5.6 billion gallons of water with an estimated power potential of 8,500 MWh. The underground powerhouse includes four large reversible turbines, each capable of pumping 27,000 gallons of water per second. The powerhouse is accessible through a 2,500-foot-long tunnel. Seven hundred feet below the surface, the cavern is longer than a football field and higher than a ten-story building.
This data has been validated by project staff through a review of publicly available information about the project, and verified by the project owner.
Project Status
Status Operational
Commissioning On 01.01.1972
Project Includes Multiple Systems No

99 Millers Falls Road
Northfield, Massachusetts 01360
United States

Utility Type
Paired Grid Resource
Project Includes Multiple Systems No
Ownership & Value Chain Partners
Ownership Model Third-Party-Owned
Equity Owner 1 FirstLight Power Resources (GDF Suez Energy North America)
Equity Owner 1 Percent 100%
O&M Contractor FirstLight Power Resources (GDF Suez Energy North America)
Developer Northeast Utilities
Cost & Performance
Performance Performance metrics not available
Capital Expenditure $140000000
Service Use Case Electric Energy Time Shift
Electric Supply Capacity
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