Germany’s RWE has joined hands with distributed battery energy storage system (BESS) solutions provider Polarium to bring aggregated battery flexibility to the German power market. From late 2026, RWE will optimize 50 MW/135 MWh BESS from Polarium’s portfolio within its trading operations. More than 1,600 battery systems across Germany are linked through Polarium’s cloud platform and operated as 1 virtual battery. This enables real-time control, secure market participation, and better use of unused capacity in batteries and the grid, explained RWE.
The agreement allows underused backup battery capacity to participate in flexibility markets in real time. Through a multi-asset tolling structure, Polarium provides access to aggregated capacity while RWE manages trading and optimization across relevant markets. The decentralized system is expected to support grid stability and renewable integration by spreading storage across multiple locations – reducing strain on infrastructure and improving system resilience.
“By working with Polarium, we are bringing thousands of smaller storage units into the flexibility market, where they can contribute to make the energy system more robust, generate additional value and help to keep the system in balance in real time,” said Ulf Kerstin, the Chief Commercial Officer at RWE Supply & Trading.
Limes Renewable Energy of Italy has secured an environmental permit for its 150 MW / 5-hour BESS Ganso project in Chile’s Valparaíso Region, marking progress in its Latin American expansion. The approval was granted in April 2026 through Chile’s fast-track 'Consulta de Pertinencia' process, used for projects with minimal environmental impact.
For Limes, the milestone follows 2 other environmental approvals received within 5 months for Pradera Larga (solar PV plus storage) and BESS Huañil. Located in central Chile’s main demand hub, BESS Ganso is positioned to serve industrial users and emerging data center demand, supporting potential power purchase agreements (PPAs).
Limes’ pipeline in Chile now includes around 180 MW of solar PV and 620 MW of BESS, with initial projects expected to reach the ready-to-build stage by late 2026. The company is advancing partnerships as it moves toward an independent power producer (IPP) model, while continuing to expand across Latin America.
ACME Solar Holdings Limited has cumulatively operationalized over 2 GWh of BESS capacity in Rajasthan, marking a key milestone in its storage expansion. The company’s total operational BESS capacity now stands at 591.18 MW / 2,031.24 MWh across its subsidiaries in the state, placing it among the early Indian developers to reach this scale, it claims.
The projects are designed to support grid stability by storing power during low-demand periods and supplying it during peak demand, helping balance supply and demand. ACME Solar aims to scale its total BESS capacity to 10 GWh by 2027 as part of its broader renewable energy growth strategy. It touts a diversified portfolio of over 8 GW across solar, wind, hybrid, and storage projects, with significant capacity under construction, including around 15 GWh of planned energy storage installations.
Headwater Energy, the US-based IPP, has completed the acquisition of distributed solar and storage developer Arena Renewables. The latter’s nearly 1 GW development pipeline will benefit from Headwater’s financing and operational capabilities, says Headwater. Launched in 2023, Arena is expected to benefit from improved access to construction financing, tax equity, and capital solutions. It will help shorten timelines from development to commissioning.
Arena’s leadership team will continue to run operations, with support from Headwater’s capital and infrastructure. Both companies said the acquisition aligns their strategies to expand clean energy deployment across US markets while maintaining Arena’s existing policy-led approach to project development.
Asset manager Allianz Global Investors has acquired a 51% stake in Green Energy Storage Initiative (GESI). GESI is developing 3 large-scale battery storage projects in Bavaria and Lower Saxony in Germany with a combined grid connection capacity of about 2.6 GW. This makes it one of the largest of its kind in Germany.
The projects, planned for commissioning by 2029, will utilize existing grid infrastructure, including former power plant sites. Allianz says this marks its 2nd direct equity investment in Germany’s battery storage sector within a short period. It will strengthen Allianz’s position in energy storage.
NLC India Limited (NLCIL) has signed a €100 million loan agreement with Germany’s KfW to support its solar power and BESS initiatives. It plans to use the funds to expand its renewable energy portfolio, improve grid reliability, and diversify its financing sources. Senior officials from both organizations attended the signing ceremony, with additional participation from KfW representatives based in Frankfurt.
Global renewable energy company Sonnedix has signed 3 PPAs with Copec EMOAC for the 117 MW Sonnedix Librillo BESS project in Taltal, Antofagasta Region, Chile. The standalone BESS, with a 5-hour capacity (643.8 MWh), will store renewable energy for nighttime delivery. It says the project will improve grid flexibility and support clean energy integration in northern Chile.
The project will supply power via the Francisco node and is expected to begin commercial operations in April 2027. The agreements mark a step forward for long-term renewable energy and storage contracts in Chile, enhancing system stability, reducing solar variability, and supporting decarbonization, stated Sonnedix.
Abu Dhabi’s Masdar and Montenegro’s Elektroprivreda Crne Gore (EPCG) have agreed to establish a 50:50 joint venture to develop large-scale renewable energy projects in Montenegro. Headquartered in Nikšić, the JV will deploy technologies including solar PV, wind, hydropower, pumped hydro storage, stand-alone battery storage, and hybrid systems.
The partnership aims to support Montenegro’s domestic energy demand while enabling exports of renewable electricity to the Western Balkans and Southern Europe, including via an existing subsea link to Italy.
The JV combines EPCG’s local generation capacity with Masdar’s global project development expertise to strengthen energy security and accelerate the country’s energy transition, stated the JV partners. The move builds on earlier cooperation agreements and Masdar’s existing footprint in Montenegro, including its investment in the Krnovo wind farm, while supporting its broader expansion across Southeast and Central Europe.