Orsted Starts Commercial Operations at 250 MW Old 300 Storage in Texas
- Energy Storage News Utility-Scale BESS
Marin Holt
- 0
- 6 minutes read
- Storage capacity: 250 MW / 500 MWh
- Duration at full output: 250 MW for 2 hours
- Co-located solar: 430 MW Old 300 Solar, online since 2024
- Property tax over project life: $110 million
- Location: Needville, Fort Bend County, Texas (ERCOT)
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Orsted said on August 5, 2026 that Old 300 Storage, a 250 MW battery plant in Needville, Texas, reached commercial operations and now runs on the ERCOT grid. The system stores 500 MWh. It holds 250 MW of output for two hours. Tesla built the Megapack units at its Lathrop, California factory. The battery sits beside Old 300 Solar, a 430 MW plant that has run since 2024. Orsted counts the site as its twelfth project in Texas and part of a 6 GW US onshore portfolio. The company expects the combined solar and storage site to pay about $110 million in property taxes over its life.
What Is Online
Old 300 Storage runs independently from the solar plant next to it. ERCOT dispatches the battery as a separate resource. Melissa Peterson, president of Orsted Americas Onshore, tied the project to tight supply and demand margins on the Texas grid. She said battery storage has already carried load in those hours. Old 300 Solar has served roughly 80,000 Texas homes and businesses since 2024.
Two hours of duration is a market choice, not a technical ceiling. ERCOT pays well for fast response through its ancillary services products, and a two-hour shape collects that revenue. Longer durations earn less per installed megawatt-hour under the same rules. Orsted did not disclose how much of the plant’s output it has contracted and how much it will bid into the merchant market. MGRID could not independently verify the split.
Why It Matters
A 250 MW resource earns its keep on the summer evenings when solar output falls and demand holds. Old 300 Storage adds no generation to Texas. It shifts existing solar output a few hours later in the day. Read the announcement as new timing rather than new supply. The $110 million property tax figure lands in Fort Bend County over the project life, and that is the number local officials will quote when the next project asks for a permit.
Critical Perspective
Old 300 Storage holds 250 MW for two hours, which is the shape that earns most from ERCOT ancillary services today rather than the shape that covers a long outage. Orsted took the final investment decision on this project alongside a plan to reduce capital investment spending, so the commissioning closes out a commitment made against a very different balance sheet. The company booked multi-billion-dollar writedowns on its US offshore portfolio and abandoned Ocean Wind 1 in New Jersey in 2023, which is the context a commercial-operations release rarely carries. If ancillary service revenue compresses as more two-hour batteries reach ERCOT, what is the merchant case for Old 300 in 2030?
Sources
- http://www.prnewswire.com/news-releases/orsted-announces-commercial-operations-of-energy-storage-system-in-fort-bend-county-tx-302844075.html
- https://www.solarpowerworldonline.com/2026/08/orsted-adds-500-mwh-of-tesla-bess-to-ercot-grid/
- https://electrek.co/2026/08/05/tesla-megapack-power-orsted-big-new-texas-grid-battery/
- https://www.energy-storage.news/orsted-takes-fid-on-500mwh-texas-bess-plans-to-reduce-capital-investment-spending/
