Spearmint Energy, a U.S.-based energy storage company, has secured a $325 million expanded debt facility from Nuveen Energy Infrastructure Credit, Elda River Capital Management, Harrison Street Asset Management, and Aiga Capital Partners.

The company said the debt facility will strengthen its capital base and support strategic initiatives tied to its battery storage portfolio.

Spearmint expects to use the capital to advance its operating portfolio, which includes the Tierra Seca, Seven Flags, and Revolution projects. The funding will also support its development portfolio, which includes projects across the U.S.

“Battery storage is becoming an increasingly important part of the nation’s energy infrastructure, and Spearmint is helping to advance that buildout with high-quality assets and a clear growth strategy,” said Don Dimitrievich, Head of Nuveen Energy Infrastructure Credit. “We are pleased to support the Spearmint team through this debt facility as they continue to expand access to reliable, resilient power for American consumers.”

Spearmint develops large-scale battery storage projects that provide grid services and support a reliable power supply. Battery storage projects store electricity and discharge it when grid demand rises or renewable generation declines, helping grid operators manage supply and demand.

In May, the company closed approximately $450 million in financing for Red Egret, a 300 MW/600 MWh standalone battery energy storage project in Texas City, Texas. The financing package comprises a construction facility, an investment tax credit transfer, and preferred equity. Spearmint said construction has begun, and the project is expected to be completed in 2027.

Spearmint currently operates 350 MW/700 MWh in ERCOT, with an additional 300 MW/600 MWh under construction, and has projects under development throughout the U.S.

The company said the expanded debt facility will increase its financing flexibility, allowing it to support operating assets, fund platform-level initiatives, and pursue additional storage opportunities.

According to Mercom’s recently released Q1 2026 Energy Storage Funding and M&A report, announced Energy Storage project funding increased 115% YoY in Q1 2026, compared to $8 billion raised in the same period in 2025.