Energy Vault Holdings Inc. has begun construction on the SOSA Energy Center, a 150 MW/300 MWh battery energy storage project in Madison County, Texas. The project advances the company’s property asset strategy and is the fourth facility to enter construction under its Asset Vault platform, the developer said.
The site, originally developed by Shell subsidiary Savion, was acquired by Energy Vault in late 2025. Commercial operation is planned for the second quarter of 2027.
Madison County is approximately 90 miles northwest of Houston along the Interstate-45 corridor, placing the project within easy reach of one of the state’s largest freight hubs. Although located there, Energy Vault says the facility will operate in the state grid operator ERCOT’s North Market, which covers the Dallas–Fort Worth area and surrounding North Texas counties.
“Breaking ground on the SOSA Energy Center so quickly after the acquisition demonstrates the speed with which we are executing and growing Energy Vault’s Asset Vault platform,” said Robert Piconi, President and CEO. He added that the project “underlines our strategic commitment to the Texas ERCOT market, one of the most dynamic energy markets in the United States.”
The project will use Energy Vault’s third-generation B-VAULT DC battery system, a utility-scale DC-coupled platform built for grid storage. Company documentation describes a modular enclosure that supports different battery and inverter configurations and is operated via the company’s VaultOS control software. The system is designed to provide support for grid balancing and long-term sustained operation.
The company is in advanced talks on a multi-year acquisition agreement with an undisclosed investment-grade buyer and plans to perform long-term engineering, procurement, construction and service work to maintain control throughout the project’s life cycle.
“Texas continues to lead the nation in renewable energy adoption and grid modernization, becoming a critical market for our growth strategy,” Piconi said.
With SOSA entering construction, Energy Vault now has more than 340 MW of storage assets in operation or in progress, with additional projects scheduled to come online in 2027 and 2028.
