For years, an endless stream of Blackstone River waters has gushed over the Albion Dam, built more than a century ago to help power a nearby textile mill. Now the dam is again helping to harness the river’s power – this time to provide electricity for hundreds of homes.
Since November, a small part of the river’s flow has been used to turn what looks like a pair of giant black steel screws. Weighing 50 tons, these are known as Archimedes screw turbine generators, and they are the crux of a new small-scale hydropower project at the dam.
The design takes advantage of water falling through a channel along the east end of the dam to rotate the screws, which in turn creates electricity through a system of gears, motors and other equipment, says John Brand, manager of Albion Hydro LLC, which runs the project.
The hydroelectric plant is expected to last at least 30 years and the Albion Dam project can generate more than 2,000 megawatt hours of electricity per year – enough to power around 400 houses annually, Brand says.
“We want to ensure the project serves the Cumberland area for a long time,” Brand said.
The technology actually dates back thousands of years when ancient Greek mathematician and engineer Archimedes figured out how to use large screws to defy gravity and raise water for things such as irrigation, Brand says. Since the 1990s, Archimedes screws have used gravity to create hydropower after a company in Holland discovered that a considerable amount of hydroelectricity could be generated by simply reversing the screw.
The design of the Albion Dam project is rare in the U.S., as it is just one of two sites to deploy the Archimedes screwS, with the other located in Hanover, Conn. There are similar projects located in Canada and Africa, and the technology is more common in Europe with at least 400 Archimedes screws installed since 1993.
Before Albion Hydro took over in 2021, the project was introduced in 2017 by New England Hydropower Co. LLC, a developer focused on managing small-scale hydroelectric facilities, to help the state meet its renewable energy goals.
Since 2020, the state has been on a mission to generate 100% of its electricity from renewable energy by 2030, and hydroelectricity is part of achieving this goal.
“Rhode Island, like many states, is exploring the potential of similar hydroelectric projects as part of our broader commitment to [the] Act on Climate, aiming for net zero carbon emissions,” said Robert Beadle, spokesperson for the R.I. Office of Energy Resources. “While these projects represent a smaller fraction of our overall renewable energy portfolio, they are crucial in diversifying our energy sources and enhancing grid resilience.”
The project is also part of the state’s Renewable Energy Growth Program, which is administered by Rhode Island Energy and was established by the General Assembly in 2014 to promote more renewable energy development. The initiative offers a performance-based incentive program that pays customers a fixed-rate per kilowatt hour of renewable energy they produce.
But before it could get up and running, Beadle says the project had to go through a rigorous process, including environmental assessments, public feedback and coordination with federal and state regulations to make sure it is sustainable and will have a minimal effect on the environment.
With low rotation rates, an Archimedes screw reduces the negative effects on fish and other aquatic life, Brand says. The screw is also among the more versatile hydropower technologies, as it can operate in a wide range of environments, including moderate flow rates that might not be good for traditional turbines.
While the Albion Dam project has been running for months now, New England Hydropower has plans in place to repurpose the Ashton Mills Dam just down the stream using different technology.
Before choosing to develop Albion and Ashton Mill dams, the company evaluated hundreds of dams based on factors such as cost, the river’s flow, ability to generate electricity, and environmental and social effects, said Chris Conover, spokesperson for New England Hydropower.
“Ultimately, we’re trying to build a commercially responsible power plant to develop green energy,” Conover said. He declined PBN’s request to discuss the Ashton Mills proposal.
For centuries, the Blackstone River was known as America’s “hardest-working river” because its steady drop made it good for providing waterpower. At one time, countless mills lined its banks with dams harnessing the flow.
But despite the river’s working past, some groups have opposed the construction of the hydropower project at the Ashton Mill Dam.
John Marsland, president of the Blackstone River Watershed Council, says he’s concerned about historical conservation because the project is located within the Blackstone River Valley National Historic Park. He argues that the Federal Powers Act prohibits the Federal Energy Regulatory Commission from issuing a license for a hydroelectric power project located within the national parks system.
In comments submitted to the commission, the National Park Service echoed Marsland’s concerns, stating the project would raise water levels, potentially destroying the “delicate remaining historic fabric of the early 19th-century canal.”
