Berlin, 5 May 2025 - Vattenfall and terralayr have signed a 7-year, 55 MW multi-asset capacity tolling deal — an industry-first virtual battery tolling structure
Energy utility Vattenfall and terralayr are setting a milestone in the power and energy market: with the first known multi-asset capacity toll, the two companies have signed a groundbreaking offtake agreement for a decentralized fleet of battery storage systems. The batteries are developed, built, and aggregated by terralayr through its proprietary flexibility platform. A portion of the total capacity is then operated by Vattenfall in Hamburg under a long-term offtake agreement and optimized in the energy markets.
The seven-year agreement covers 55 MW of capacity drawn from a larger portfolio of terralayr-operated storage sites, spanning eight locations across Germany. The agreement demonstrates how battery flexibility can be scaled efficiently without hardware investment — a model that sets an important precedent for the emerging battery storage industry and contributes to the wider decarbonization of the energy system. Operations across the distributed portfolio are scheduled to begin by the end of 2025.
Innovative structure: Virtual BESS-portfolio replaces single-asset tolling structure
Unlike conventional tolling agreements tied to a single physical asset, this deal is structured around aggregated capacity from multiple decentralized grid-scale batteries.
For the first time, this structure opens large-scale tolling agreements to smaller battery systems — a configuration that was rarely feasible within conventional models. For storage investors and operators, the aggregation of assets and subsequent long-term offtake brings stable revenues and improves financing conditions, contributing to the overall expansion of battery storage in Germany.
In an energy system increasingly shaped by intermittent energy generation from wind and solar, flexible storage is becoming essential for grid stability. The distributed layout of this battery network also helps offset regional inefficiencies in the power market and creates new opportunities for energy optimization.
Battery storage as a strategic lever for Vattenfall
The storage partnership provides Vattenfall with a range of strategic advantages: it enables more efficient integration of renewable energy by balancing fluctuations in wind and solar production — while reducing the need for costly grid interventions. At the same time, targeted optimization of battery assets across energy and balancing markets supports price stability and grid reliability.
terralayr makes storage flexibility available via API
terralayr is responsible for the development, construction, financing, and operation of the physical storage assets. These assets are then aggregated via terralayr’s proprietary cloud-based software platform. A key technical advantage is the streamlined access to capacity: Vattenfall connects to the batteries via a centralized API. This enables efficient management of diverse systems, ensures consistent performance standards across heterogenous assets, and reduces integration effort for future storage additions.
OpEx instead of CapEx: Flexibility without balance sheet risk
Unlike owning or directly leasing a large-scale battery storage system, this model does not require Vattenfall to make significant capital investments or carry lease-related liabilities on its balance sheet. Instead, the service is treated as an operating expense (OpEx) — offering a flexible, scalable, and balance sheet–light solution.
About Vattenfall
Vattenfall is a European energy company with around 21,000 employees. For more than 100 years, the company has electrified industries, powered homes, and driven modern life through innovation and collaboration. Vattenfall’s mission is fossil freedom — enabling fossil-free living, mobility, and production within one generation.
About terralayr
terralayr is a fully integrated energy flexibility provider. terralayr addresses the massive global need for energy storage by aggregating its own as well as third party battery storage assets. A cloud-like software platform makes energy flexibility accessible „as-a-service” to many customer groups, including power producers, grid operators and large consumers of power such as data centers. terralayr develops and operates a portfolio of its own battery storage assets, with currently two assets operational, several assets in construction and a total development pipeline of over 5 GW in Germany. The company’s leadership team is composed of industry experts with previous positions in companies such as Siemens, Deutsche Bank, RWE, BCG, Fluence, dare, Next Kraftwerke, Limejump, and Pexapark.