Duke Energy has announced the commissioning of a 50-megawatt battery energy storage system (BESS) at its former Allen coal plant on Lake Wylie, which serves customers in both North Carolina and South Carolina. The company completed the $100 million project ahead of schedule and under budget, with final testing currently underway. This installation is part of Duke Energy’s broader initiative to expand battery storage across the Carolinas.
Construction is set to begin in May on a second, larger BESS at the same site. This upcoming 167-megawatt facility will be the company’s largest battery project to date and will be built on land previously used for emissions control infrastructure at the retired coal plant.
Both lithium-ion battery systems qualify for federal investment tax credits that will offset 40% of their cost for customers. This includes an additional 10% credit for reinvesting in an energy community, following the retirement of the Allen coal plant in December 2024.
Kendal Bowman, president of Duke Energy North Carolina, stated: “We’re building new resources to keep the Carolinas’ economy thriving, while reinvesting in a former coal plant community that helped power this region for decades. Repurposing existing energy infrastructure and taking advantage of federal funding significantly offset costs for our customers while continuing to support rapid growth across the region.”
Utility-scale batteries like these are particularly valuable during cold winter mornings before solar generation begins. They can also store surplus energy generated during low-demand periods—such as nuclear power from nearby Catawba Nuclear Station—for use when demand increases.
Duke Energy’s long-term strategy includes further investments in battery storage throughout multiple counties in North and South Carolina. The company’s proposed 2025 Carolinas Resource Plan projects adding 6,550 megawatts of batteries by 2035 to maintain grid reliability and meet increasing demand—a figure sufficient to power more than five million homes during peak times.
The plan calls for maintaining a diverse mix of solar, storage, nuclear, and natural gas generation sources as electricity needs are expected to grow eightfold over the next fifteen years compared with the previous fifteen years.
Duke Energy also intends to install battery storage at both retired coal plants along Gaston County’s stretch of the Catawba River—the Allen site (operational from 1957–2024) and Riverbend (1929–2013). Construction on a 115-megawatt BESS at Riverbend is slated to begin late next year with completion targeted for late 2027.
Bryan Walsh, vice president of Regulated Renewables and Lake Services at Duke Energy, commented: “We are proud of how this site and its people continue to support our customers. Multiple former Allen plant employees now work on our Regulated Renewables team, which maintains and operates the new batteries at Allen and elsewhere in the Carolinas. Duke Energy’s test site for new battery technologies, its Emerging Technology and Innovation Center, is also in Mount Holly.”
Additionally, as part of an ongoing rate review with state regulators, Duke Energy has proposed building a third BESS at Allen by late 2028 along with a regional operations center that could employ up to fifty people. These plans remain subject to regulatory approval.
Duke Energy Carolinas provides electricity across a service area covering twenty-four thousand square miles in North Carolina and South Carolina. Its parent company supplies electric or natural gas services to millions across six states.
More information about these initiatives can be found on duke-energy.com and through various social media channels operated by Duke Energy.
