Northfield Mountain (hydroelectricity facility)

42°36′39″N 72°28′17″W / 42.61083°N 72.47139°W / 42.61083; -72.47139 Northfield Mountain is a pumped-storage hydroelectric plant and reservoir located on and under the similarly named Northfield Mountain in Erving and Northfield, Massachusetts. It is currently owned by FirstLight Power Resources[1] (formerly NE Energy), which purchased the facility from Northeast Utilities in 2006.[2]

History

Engineering studies for the plant began in October 1964, with early site preparation starting three years later. In 1972 its 1,168 megawatt hydroelectric plant became operational as the largest such facility in the world.[citation needed] The facility was built to balance the supply from the nearby Vermont Yankee Nuclear Power Plant.[3]

Design

The plant was built entirely underground, and located about 5.5 miles (8.9 km) up the Connecticut River from Turners Falls Dam. A stretch of the Connecticut River, extending some 20 miles (32 km) north from this dam to the Vernon Dam, Vermont, serves as the station's lower reservoir. During periods of lower electrical power demand, the plant pumps water from this lower reservoir through the Northfield Mountain Tailrace Tunnel to a man-made upper reservoir. At times of high demand, water is released to flow downhill from this upper reservoir through a turbine generator, where it then collects in the lower reservoir to be stored until again pumped to the upper reservoir.

Northfield Mountain's upper reservoir covers 300 acres (120 ha) at 800 feet (240 m) above the river, with total storage of 17,186 acre-feet (21.199 GL) of water. Its underground powerhouse lies at 700 feet (210 m) below the surface and is accessible through a 2,500-foot (760 m)-long tunnel; it includes four large reversible turbines, each of which can pump 15,200 cubic feet (430 m3) of water per second and release 20,000 cubic feet (570 m3) of water per second to generate 1,168 MW of electricity.[4] The turbines can ramp up in 10 minutes, and deliver full power for 8 hours.[3]

Controversy

The plant was built to store excess energy from the Vermont Yankee Nuclear Power Plant, but that plant was shut down in 2014. The pumped-storage plant is still in operation, but according to activist site Connecticut River Defenders [5] it is no longer needed, as it is only storing energy from fossil-fuel plants, and is harming the Connecticut River ecosystem, killing all river life that passes through its turbines.

References

  1. ^ "Power Facilities :: H2O Power Limited Partnership". www.h2opower.ca. Archived from the original on 2016-07-23.
  2. ^ "Your Dedicated Source of Hydropower News".
  3. ^ a b Gellerman, Bruce (December 2, 2016). "New England's Largest Battery Is Hidden Inside A Mass. Mountain". www.wbur.org. WBUR-FM. Retrieved 2017-12-13. When this facility was built, it was actually the largest pumped storage facility in the world. Vermont Yankee being a nuclear power plant generates power 24/7, or what they call base load," Bakas says. "So as a result of that at night they had all this excess power on the grid. So somebody needed to take it. So this plant was conceived and built to take that off-peak power and utilize it through pumping water during off-peak periods.
  4. ^ "Northfield Mountain Pumped Storage Project". www.northfieldrelicensing.com. Archived from the original on 2015-04-15.
  5. ^ "Connecticut River Defenders".