RWE Partners with Polarium to Aggregate Thousands of Battery Systems into Scalable Energy Flexibility Platform

RWE Partners with Polarium to Aggregate Thousands of Battery Systems into Scalable Energy Flexibility Platform

(IN BRIEF) RWE and Polarium have partnered to create a virtual battery by aggregating more than 1,600 distributed battery systems across Germany, enabling their combined capacity to be traded in energy markets. Starting in late 2026, RWE will optimize at least 50 MW of power from this portfolio under a multi-asset tolling agreement. The approach transforms backup battery systems into a flexible energy resource, supporting renewable integration and grid stability. The portfolio is expected to expand significantly, reaching up to 300 MW across thousands of sites. The initiative highlights the growing importance of decentralized energy storage and digital platforms in modern power systems.

(PRESS RELEASE) ESSEN / STOCKHOLM, 22-Apr-2026 — /EuropaWire/ — RWE has entered into a new agreement with Polarium to unlock the value of distributed battery systems by aggregating them into a large-scale virtual energy resource. The collaboration introduces a multi-asset tolling model that brings together thousands of smaller battery installations into a single, market-ready flexibility platform within Germany’s power market.

Under the agreement, RWE will begin optimizing at least 50 megawatts of capacity, equivalent to 135 megawatt hours of stored electricity, from Polarium’s distributed battery portfolio starting in late 2026. These assets are drawn from more than 1,600 behind-the-meter battery systems, which are connected through Polarium’s cloud-based platform to operate as a unified virtual battery.

This approach enables real-time coordination and participation in energy markets, transforming what were originally standalone backup systems into a scalable and flexible energy resource. By pooling unused storage capacity, the system can support grid stability and enhance the integration of renewable energy sources.

The portfolio is expected to grow significantly in the coming years, with projections reaching approximately 300 megawatts and 810 megawatt hours, distributed across more than 10,000 battery units. This expansion highlights the increasing role of decentralized storage solutions in modern energy systems.

The partnership is structured as a multi-asset tolling agreement, allowing RWE to access and commercialize the aggregated flexibility across various energy markets. Unlike traditional tolling arrangements that typically involve a single large storage facility, this model integrates numerous smaller systems via a digital platform, offering greater adaptability and scalability.

Polarium’s battery systems are primarily deployed to provide backup power for critical infrastructure. However, by leveraging excess capacity not required for backup, the company can aggregate and monetize this flexibility without compromising reliability for end users. This dual-purpose approach enhances asset utilization while maintaining operational readiness.

The distributed nature of the battery network also contributes to improved grid performance. By spreading storage capacity across multiple locations, the system reduces pressure on individual grid nodes, increases resilience, and distributes operational risk. Additionally, a unified interface allows for efficient integration of new assets and consistent performance management across the network.

This collaboration builds on RWE’s broader experience in developing innovative energy trading and flexibility solutions, demonstrating how digital platforms and decentralized assets can be combined to support a more balanced and sustainable energy system.

For further enquiries:

Regina Wolter
Media Relations
RWE Supply & Trading
M +49 152 06855300
E regina.wolter@rwe.com

Peter Wasmuth
EVP New Ventures
Polarium
T +46 706553973
E peter.wasmuth@polarium.com

RWE Supply & Trading GmbH
RWE Supply & Trading is the interface between RWE and the energy markets around the world. Approximately 2,000 employees from over 70 different countries trade electricity, gas, commodities, and CO2 emission allowances. Accurate market analyses and a high degree of customer centricity enable them to create innovative energy supply solutions as well as risk management concepts for industrial operations. The trading entity also ensures the commercial optimisation of RWE’s power plant dispatch and markets electricity from RWE. In addition, there is the legally independent RWE gas storage business in Germany under the umbrella of RWE Supply & Trading.

About Polarium
Polarium develops smart battery management and storage solutions that turn energy into measurable value – mastering every watt hour. Our technology powers businesses within telecom, commercial and industrial and residential facilities worldwide. Polarium was founded in 2015 on the conviction that safe and smart energy storage solutions will be key to empower the transition to a truly, sustainable energy future. We are an impact business contributing to the energy transformation by enabling the electrification and intermittent power supply. Our cutting-edge and easily adaptable modular battery technology enables us to be in the forefront of developing state-of-the-art battery management and storage solutions for today – and tomorrow. Polarium is headquartered in Stockholm, with production in Vietnam, and customers across the world.

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SOURCE: RWE