Renewable Hydropower Takes Over & Keeps Power Flowing During a Near Shut-down

Northfield Mountain Hydro Power

While this region had just begun to face the worst of the pandemic crisis, another type of shut-down was averted thanks to a renewable energy pumped-storage generator.


As reported by the National Hydropower Association:

At 4:15pm on April 1, a fault in the switchyard of a New England nuclear plant caused the plant to trip offline. Despite the loss of over 1,200 MW of power, the equivalent of nearly half a million homes… the region’s two pumped storage hydropower facilities instantly generated power to help make up the shortfall. Instead of a shortfall … to most citizens in New England, nothing happened.ISO New England graph showing switch over to Hydro

But for the men and women in western Massachusetts working at Bear Swamp and Northfield Mountain, that is hardly the case. Within seconds, thousands of additional cubic feet per second of water came pouring through their powerhouses. This is nothing new, however. In fact, it is part of the daily routine.

Bear Swamp and Northfield Mountain function as two enormous water batteries – they pump water uphill to a reservoir during times of low energy demand and then generate electricity when demand increases by releasing water back downhill. To put the sheer magnitude of these facilities in perspective, New England’s largest lithium battery, a 6 MW battery in Nantucket, can only provide 1% of the power of Bear Swamp and 0.5% of the power of Northfield Mountain.

The two facilities are arguably New England’s most important electrical resources for maintaining grid reliability.

In addition to providing substantial emergency reserves, pumped storage hydropower is also used to smooth out variations in wind and solar generation. As New England transitions towards a clean energy economy, pumped storage hydropower will continue to be an essential resource to keep the lights on.


MGED currently purchases carbon free hydro-electric energy from the New York Power Authority Niagara Hydroelectric Power Station and from Firstlight Power, owners of the Cabot Falls and Turner Falls generators in Montague, Massachusetts. The Firstlight purchase includes the renewable attributes (also known as clean energy credits) and will increase to supply over 5 MW of power for MGED customers.