Centrica Energy and independent power producer Zelestra have entered into a long-term tolling agreement covering a 99 MW / 297 MWh battery energy storage system in Germany, the companies have announced.

Project Structure and Responsibilities

Under the terms of the deal, Zelestra will be responsible for constructing, operating, and owning the battery storage facility, while Centrica Energy — the trading arm of UK-based power group Centrica — will handle cross-market optimization of the contractually agreed capacities. The arrangement reflects a common tolling structure in which the asset owner retains physical control of the infrastructure while a trading counterparty monetizes the flexibility value across wholesale and ancillary markets.

Hilgermissen Site

The project is located at Hilgermissen in Germany. At 99 MW of power capacity and 297 MWh of energy storage, the system represents a three-hour duration asset, a configuration increasingly common in European grid-scale storage deployments seeking to participate in both short-duration frequency response markets and longer intraday energy trading opportunities.

Market Context

The agreement adds to a growing body of tolling arrangements in the European battery storage sector, where developers and independent power producers have increasingly sought to pair their project pipelines with experienced trading counterparts to manage revenue risk. Germany, with its large renewable generation base and ongoing energy transition, has become one of the more active markets for utility-scale battery deployment on the continent. Long-term tolling structures allow asset owners such as Zelestra to secure revenue visibility while enabling trading firms like Centrica Energy to apply optimization strategies across multiple market venues without carrying the capital burden of asset ownership.