Tesla Megapack 500 MWh Battery Live in Texas
Get the Energy newsletter
Daily energy & climate — solar, EVs, oil, the policy fights and tech bets shaping the transition. Free.
- Tesla Megapacks are now supporting the Texas grid at Ørsted's new 250 MW/500 MWh Old 300 battery storage project in Needville, southwest of Houston, fully connected to ERCOT
- Old 300 Storage can deliver 250 MW of power for two hours at full output, with Megapacks built at Tesla's Megafactory in Lathrop, California — described as the largest industrial utility-scale BESS factory in the US
- Each Tesla Megapack in the current two-hour configuration provides about 1.9 MW of power and 3.85 MWh of storage, arriving with battery modules, inverters, thermal management, and controls integrated into one unit
- Old 300 Storage sits next to Ørsted's 430 MW Old 300 Solar but operates independently, able to charge from and discharge to the wider ERCOT grid rather than only storing solar output
- Old 300 Solar has been operating since 2024 and generates enough power annually to serve around 80,000 Texas homes and businesses; together, the solar and battery projects are expected to generate around $110 million in property tax revenue
- Ørsted says the project expands its operating US onshore portfolio to around 6 GW, while Melissa Peterson, president of Ørsted Americas Onshore, noted that battery storage 'has played a large role' in ERCOT supply during tight margins
- Tesla reports more than 58 GWh of industrial storage systems operating in over 65 countries, with the Old 300 project adding another 500 MWh deployment to its stationary storage business
Why it matters: The 500 MWh deployment reinforces Tesla's position in the stationary storage market, where it claims over 58 GWh deployed across 65 countries. For Ørsted, the project expands its US onshore portfolio to 6 GW and pairs battery storage with a 430 MW solar farm already powering 80,000 Texas homes. The site also underscores ERCOT's growing reliance on grid-scale batteries to manage tight supply margins during Texas weather-driven demand spikes.
Ask SkimNews
