Renewable energy firm Ørsted has announced the beginning of commercial operations for Old 300 Storage, a 250 MW / 500 MWh battery system in Needville, Texas.

Located in rural southeastern Texas, the plant sits about 40 miles outside of the Houston metropolitan area. The Old 300 project will fully integrate itself into the ERCOT grid, according to Ørsted officials, and pushes the company’s U.S.-based energy portfolio to more than 6 GW.

“Battery energy storage has played a large role in providing much needed power to ERCOT in times of tight supply and demand margins,” says Melissa Peterson, president of Ørsted Americas Onshore. “Achieving commercial operations at our Old 300 Storage project will have tangible benefits, such as strengthening grid reliability by providing additional resources to Texas grid operators and allowing for more diverse and localized energy options as electricity demand continues to grow.”

The battery system is co-located with Old 300 Solar, a 430 MW photovoltaic project. The two will be operated independently, Ørsted representatives say, with each project helping to improve grid stability throughout the Lone Star State.

Old 300 Solar has provided electricity to about 80,000 Texan homes and businesses since 2024, the company says, and was one of the largest solar projects to see start of operation during that year. Combined with Old 300 Storage, the two sites will add about $110 million in property tax revenue to the Houston area.

Partnering with Tesla

For Old 300 Storage, Ørsted partnered with EV manufacturer Tesla, officials say. The Elon Musk-led battery giant provided Megapack battery systems manufactured in California to the new Ørsted project, with the cells designed specifically for large project applications.

“Designed specifically for utility-scale applications, these batteries have a proven track record for performance and safety, meeting the most stringent global codes and standards,” the company says. “They have been successfully deployed across Texas, throughout the US, and in over 65 countries worldwide. To further enhance safety, Ørsted and Tesla proactively collaborated with the Needville Fire Department to provide comprehensive education on the latest product technology and safety response protocols.”

Demand for reliable energy storage has spiked in the past few years, since the advent of AI data centers and other large load projects. Both Old 300 projects work as multi-technology solutions, Ørsted says, helping to meet the challenges of modern energy demands and ensure grid reliability across the U.S.

Tags: batteries, BESS, ESS, project, storage, Tesla, Tesla Megapack, Texas, utility-scale, Ørsted