Pumped storage units help stabilize the grid by acting as giant batteries: Water is pumped from the lower to the upper reservoir when there is surplus energy, and, during times of demand, water from the upper reservoir is released, generating electricity as the water passes through the turbine. This technology is the largest source of long-duration energy storage globally, representing about 94% of total energy storage capacity, according to the International Hydropower Association.
A History of Hydropower and Turbomachinery
Hydropower’s continued use as a renewable energy source requires complex hydro turbines and other rotating machines to electrify many regions worldwide.
The Niagara Falls region has been a hotbed for harnessing hydropower since the mid-1700s when power was initially obtained by diverting water from the falls to turn waterwheels at a small sawmill—an early form of the hydro turbine. Since then, advancements in hydro turbine technology and the buildout of hydroelectric plants have transformed the region into an epicenter of continuous, sustainable power.
Today, hydroelectric power plants in the Niagara Falls’ Canadian region generate almost 2 million kW of electricity, while the American plants—Robert Moses Niagara Power Plant and the Lewiston Pump Generating Plant—combine for more than 2.6 million kW. Between these two plants, a combined 25 turbines are being spun. In fact, Niagara Falls is New York State’s biggest electricity producer. According to the U.S. Department of Energy, hydropower accounts for 28.7% of the country’s total renewable electricity generation and approximately 6.2% of total electricity generation.
The Ontario region, via a partnership between Ontario Power Generation (OPG) and GE Vernova, established a 15-year plan to refurbish up to five hydropower plant stations; this includes up to 25 units at the Sir Adam Beck Complex in Niagara Falls—increasing its capacity by up to 50 MW. The hydroelectric refurbishment plans will help secure up to 1,700 MW of clean electricity and extend their life by another 30 years.
Hydropower stations house complex rotating machinery that is exposed to environmental elements, varying elevations, and more, day in and day out. But there is no one-size-fits-all turbomachine used in hydropower plants.
“In a hydropower plant, the rotating machines—turbines and generators—convert the mechanical energy of flowing water through the units into electrical energy delivered to the grid. According to the site characteristics, mainly the differences in elevation between upstream and downstream reservoirs or river levels, different kinds of turbines [can be installed],” explained Jean-Michel Milles, Hydro Power Head of Engineering at GE Vernova’s Hydro Business.