New battery storage partnership: green flexibility and ENERTRAG launch first joint project in Tantow

green flexibility and ENERTRAG have formed a strategic partnership to jointly develop a large-scale battery storage project. The battery storage system is planned to be built in Tantow (Brandenburg / Germany), in close proximity to ENERTRAG’s own substation. With a planned capacity of 60 MW and 130 MWh of storage, the project will make a significant contribution to grid stability and improve the integration of renewable energies. Commissioning is scheduled for the first quarter of 2026.

Kempten/Dauerthal, May 20, 2025

The partnership brings together two companies with highly complementary expertise: ENERTRAG, a long-established developer and operator of renewable energy systems, contributes decades of experience in wind and solar power. green flexibility adds deep technical know-how in the planning, construction, and long-term operation of large-scale battery storage systems. Together, the companies aim to develop tailored storage solutions to relieve pressure on the grid, maximize the use of renewable energy, and increase security of supply.

€45 million investment in the energy transition

The battery storage system will be built on an area of approximately 4,000 square meters and is designed to balance fluctuations in power generation from renewable sources. It will absorb excess energy when the grid is overloaded and feed it back into the system when demand is high. This not only helps stabilize the grid, but also increases the efficiency of renewable energy usage and reduces the curtailment of wind and solar power.

The total investment for the project is around €45 million. Construction and long-term operation will be handled by a jointly established project company. The Tantow battery storage project is currently in the final planning phase.

Voices from the project partners

""With ENERTRAG, we have an experienced and trusted partner at our side. Together, we are developing innovative solutions to move the energy transition forward. Only through strong collaboration will the transformation of our energy system succeed – and we are excited about this partnership and the journey ahead." – Christoph Ostermann, Co-Founder and CEO of green flexibility.

"Battery storage is a key building block of a future-proof energy system. Together with green flexibility, we are launching a project in Tantow (Brandenburg) that will reliably integrate renewable energy into the grid. Partnerships like this are essential to making the energy transition efficient, secure, and economically viable." – Dr. Gunar Hering, CEO of ENERTRAG

About ENERTRAG

For more than 25 years, ENERTRAG has been driving the energy transition. Over 1,200 employees plan, build, and operate hybrid power plants based on wind and solar energy, proprietary grid infrastructure, batteries, and electrolyzers. These systems reliably and efficiently deliver electricity, heat, and green hydrogen – replacing the need for any fossil-fueled power plant.

With our own facilities, we generate around 2,000 gigawatt hours of electricity from wind and solar each year and have been producing green hydrogen since 2011. Based on this foundation, we are developing energy projects with more than 30 gigawatts of capacity – across nine countries on four continents.

ENERTRAG stands for the global energy supply of the future: sustainable, secure, and regionally anchored – to help ensure a livable planet.