Hidden deep within Northfield Mountain lies a pumped storage hydroelectric generating plant capable of producing over one million kilowatts of electricity. One of the most versatile power stations in the United States, Northfield Mountain is incredibly flexible in its generation capacity. By using its four units singly or in combination with one another, Northfield can produce from 125,000 kilowatts to 1,120,000 kilowatts of electricity. Equally important is the ability to reach peak production within three minutes, which can be critical during times of emergency power needs. A typical fossil fuel plant might take up to four hours to reach its full capacity.
Separate tours visit the underground power station and the upper reservoir.
The Northfield Mountain station is located 700 feet below the surface of the mountain. That station is longer than a football field, as wide as a four lane highway and taller than a ten story building. Within this cavern is a station that has four generators, which can also be used in reverse to pump water to the upper reservoir. Other areas in the power plant include a machine shop, control room, offices and a small parking area. As you can imagine, it is a huge underground complex.