Centrica Energy and Zelestra Sign Tolling Deal for Germany's 297 MWh Hilgermissen BESS

Centrica Energy and Zelestra have signed a physical tolling agreement for 99 megawatts and 297 megawatt-hours of battery storage capacity at Zelestra's Hilgermissen project in Lower Saxony, Germany. Zelestra will develop, construct and own the three-hour standalone storage facility, with engineering and procurement work completing this year ahead of construction starting in 2027 and full operations expected in the second half of 2028.

 

Under the agreement, Centrica Energy will trade and optimise the contracted battery capacity through its multi-market trading approach, enabling participation across Germany's Day-Ahead, Intraday and Ancillary Services markets. That optimisation function is distinct from ownership: Zelestra bears the capital cost and physical development of the asset, while Centrica Energy manages how the battery's charging and discharging activity is deployed across different electricity markets to maximise its commercial value, a common structure that separates asset ownership from the specialised trading expertise needed to optimise a storage asset's revenue across multiple market segments simultaneously.

 

UPCOMING WEBINAR

How Two Sustainability Teams Used AI to Get Audit-Ready

Online, 18 August 2026 · Cleaning spend data, building audit trails and meeting what auditors expect

 

Lower Saxony combines a substantial industrial base spanning automotive manufacturing, agriculture and food production with strong existing wind power and biomass generation, creating a grid environment with both significant industrial electricity demand and substantial variable renewable supply. That combination increases the value of flexible storage capacity capable of absorbing surplus renewable generation and releasing it when industrial demand requires it, supporting grid stability and renewable integration in a region where both factors are already pronounced.

 

UPCOMING WEBINAR

Moving Sustainable Procurement Beyond Cost to Strategic Value Creation

Online, 09 September 2026 · Balancing cost, managing supplier risk and building long-term value

 

Cassim Mangerah, managing director of Centrica Energy, described the agreement as an important milestone in the company's German flexibility portfolio, framing continued growth in that market as demonstrating demand for its optimisation capabilities. Zelestra Germany chief executive Mathias Kuenicke said the project added 300 megawatt-hours of flexible capacity to one of Europe's most connected grids and largest energy storage markets, building on a broader pipeline exceeding 2 gigawatts of solar, wind and storage projects the company has in development across Germany. Centrica Energy manages more than 18.8 gigawatts of capacity under contract globally, of which more than 85 percent is renewable assets.