‘Mining for Green Energy’
Group discusses repurposing Negaunee mine shaft as underground hydroelectric storage system
By CECILIA BROWN
Journal Staff Writer
MARQUETTE — As communities across the nation seek cleaner and more affordable energy sources, a team of researchers from Michigan Technological University is working with the city of Negaunee to find out if the Mather B mineshaft could potentially be transformed into an underground pumped hydro-electric storage system.
The pilot study, which aims to determine if abandoned mines could be profitably converted into utility-scale batteries, was discussed by Negaunee Planning and Zoning Administrator David Nelson at the Northern Climate Network Climate at Noon event held Oct. 11 at Northern Michigan University.
The project would involve the use of upper and lower water reservoirs in the Mather B mine shaft. The water from the lower reservoir — which the groundwater-flooded areas of the mine shaft would be used for — would be pumped up to the higher reservoir during times of low energy demand and cheaper energy prices.
“When you have peak demand, it drops the water down. Then there’s turbines in the penstocks just like a regular old hydroelectric dam, and they’ll generate energy that goes out to the grid,” Nelson said. “The battery will be in there, they’re going to store all of that energy as well, so it just builds up over time. And then when the demand for power is low and it doesn’t cost as much, they just pump the water back up. And it just keeps doing that loop for 100 years or longer.”
The project, which would work in a similar manner to a hydroelectric dam — only underground — would have a minimal footprint, he said, as the system and associated water would be contained underground in a closed-loop system.
But unlike a dam, the project would not impact surface water flow, ecological systems, landscapes or scenic views, Nelson said.
“There isn’t much ground impact,” he said. “So it’s not like you’re going to have a huge facility like a giant power plant on top of this area.”
Furthermore, the group has found that capital costs are competitive with other storage technologies and the useful life of such a facility could be up to 100 years, he said.
“After you get this thing moving, there is really very little maintenance to it, other than maintaining the turbines and the power lines after a while,” Nelson said.
It’s important to recognize, he emphasized, that it’s early on in the process, and with the need for further funding, permitting and, eventually, construction, the project would probably take around a decade to complete if it moves forward.
The multidisciplinary group — consisting of engineers, sociologists, archeologists, energy and policy experts, among other professionals — has also done system modeling and geographic information systems analysis based on current electricity demands and has a water quality-study ongoing.
While the team is still in the “very, very, very early stages of a feasibility study,” funded by a $50,000 grant from the Alfred P. Sloan Foundation, they’ve found so far that there is “strong community support” for the project from local leaders and area residents after multiple interviews and a community event, Nelson said.
“Almost all their responses were positive,” he said. “Everybody seems really excited to actually reuse that site as something because right now it’s just vacant, does nothing and that contributes nothing.”
While it will be some time before the physical work on the project begins, the group’s pilot study research is due to be published in 2020, he said, noting they hope to pursue additional funding avenues for future work on the project.
The idea was also well-received by attendees of Nelson’s presentation, as it can help promote cleaner, greener energy while reusing existing infrastructure.
“The thing I love about it is it’s repurposing a previous infrastructure,” said Jessica Thompson of the Northern Climate Network, an associate professor of public relations and communication studies. “It’s taking a system that served us once and instead of building new on another plot of land, we’re looking inward and figuring out how to use an existing structure.”
All Northern Climate Network presentations are free, open to the public and sponsored by Marquette’s Climate Adaptation Task Force.
For more information on the Northern Climate Network and upcoming presentations, join and follow its Facebook group at www.facebook.com/groups/188899098115459/.
Cecilia Brown can be reached at 906-228-2500, ext. 248. Her email address is email@example.com.