The Tennessee Valley Authority will embark on a $216 million pilot project to install solar panels on top of a sealed coal ash dump following the Board of Directors’ funding approval earlier this month.
TVA plans to close in place a 300-acre coal ash dump at its 1.2-GW Shawnee Fossil Plant in Paducah, Ky., with a patented system that includes a geosynthetic liner and closure turf. The federal agency said it will attach a 100-MW solar array to the site without disturbing its integrity.
The Shawnee project is “a first-of-its-kind project in the nation that could potentially be duplicated at other suitable locations,” TVA said. It said the project will support its decarbonization goal and will preserve greenfield sites for other economic developments.
TVA still must submit the project for review under the National Environmental Policy Act and other regulatory and environmental approvals.
TVA doesn’t yet know when the solar project will achieve commercial operation.
“At this time, it is premature to know a specific timeframe, but the process is underway,” TVA spokesperson Ashton Davies said in an emailed statement to RTO Insider. She said TVA intends to begin the solar installation as it wraps up the site’s closure.
During the November board meeting, TVA COO Don Moul called the pilot a “revolutionary new approach to install utility-scale solar on closed landfills.”
“Directly attaching the mounting mechanisms to the turf layer without penetrating the liner maintains the integrity of the closed coal combustion residual impoundment,” Moul said. “This makes available to us the potential to use similar sites across the TVA footprint.”
Moul said the project alleviates “land constraints” while advancing TVA’s goal of building 10 GW in solar generation by 2035.
The agency’s goal is to achieve net-zero carbon emissions by 2050, which some conservation groups have called too gradual. The agency’s decarbonization target drew scrutiny from the U.S. House of Representatives’ Committee on Energy and Commerce. (See TVA Defends Rates, CO2 Reduction Plans in House Inquiry.)
Next year, TVA will contract with a third party to conduct a decarbonization study to analyze how it can further slash emissions.
“Moving quickly on this solar cap installation at the Shawnee site allows us to move further and faster as we build out towards our renewable generation goals,” Moul said.
Moul said Shawnee was “by and far” best situated for an initial project. He said TVA’s footprint has the potential to house up to 1,000 MW in solar generation atop sealed coal ash dumps.
“We’re very excited that this is a first step in some of the intentional actions we’ll be taking towards decarbonization,” he said.
Moul said while he wouldn’t “presuppose” the environmental review process, he said TVA estimates having the system online within two years.
He also said TVA will look into whether the Inflation Reduction Act will cover the project’s funds.
