Battery Energy Storage
Systems to propel
the Energy transition.

Sustainable action is at the core of our development work.

Battery storage systems play a crucial role in integrating renewable energies into the energy system and thus in reducing CO2 emissions in energy production.

Particularly with the phase-out of nuclear energy and coal, Germany alone will need close to 100 GW of installed storage capacity by 2030 in order to permanently produce and utilize 100% renewable electricity.

Services

Our range of activities for the development of large-scale battery storage systems covers the entire process from location analysis to planning to turnkey implementation.In order to advance development quickly and pragmatically, we enter into partnerships at different stages of the development process.

01

Location development and financing

From green field to operating energy asset. Zelos carries out the location analysis, taking into account grid-related, environmental and legal aspects. We acquire or lease land for the development of assets.

02

Grid connection and approval planning

Zelos plans, applies for and implements the grid connection as well as handles required approval and construction relared aspects.

03

Technical planning, construction and commissioning

Zelos covers the selection of equipment tailored to the location and the requirements of the project, technical planning as well as construction and commissioning.

Press Releases

In the transition to a clean energy future, reliable storage solutions are more critical than ever. Zelos Energy Developments GmbH, based in Berlin, is at the forefront of this transformation by developing utility-scale Battery Energy Storage Systems (BESS) that support a sustainable, responsible and renewable energy infrastructure.

Groundbreaking for large-scale battery storage in Klostermansfeld: Zelos brings 1 GW flagship project Van Gogh to ready-to-build

Klostermansfeld / Berlin, 1 July 2026

At the Klostermansfeld substation (Mansfeld-Südharz district, Saxony-Anhalt), the official groundbreaking marks another key milestone for Project Van Gogh, one of Europe's most significant battery storage projects. The project represents a new order of magnitude for grid-serving storage infrastructure in Germany and demonstrates the role batteries will play in the future for security of supply, grid stability and the integration of renewable energy.With an output of 1,000 MW and a storage capacity of 5,700 MWh, Van Gogh ranks among the largest battery storage systems in Europe and is currently the largest approved battery project in Germany. In arithmetic terms, its capacity corresponds to supplying around 3 million households for about four hours a day.The project was developed by Zelos Energy Developments GmbH from the early site identification stage through to ready-to-build (RtB). Following the successful permitting of the project, construction and operation now lie entirely with the project partner BW ESS.„Van Gogh shows that battery storage in Germany can no longer be regarded merely as a supplement to the energy transition, but as central infrastructure for a renewable electricity system,“ says Joshua Seib, Managing Director of Zelos. „We are proud to have developed this project to ready-to-build. For us, the groundbreaking is also an important proof of our own capabilities.“Projects of this dimension do not come about by chance: they require a central grid node with suitable infrastructure, must be carefully integrated into the landscape, and depend on competent partners on all sides. Precisely this constellation has been realised at the Klostermansfeld site. Before such a project can be built, years of planning and permitting are also required – from environmental and emissions-control assessments through to the grid connection agreement. It is exactly this demanding development work that Zelos undertook.Value creation for the municipality of KlostermansfeldFrom the outset of development, care was taken to ensure that the project benefits the municipality over its entire lifetime. Klostermansfeld will benefit from significant trade tax revenues. In addition, there are acceptance measures – both already today and over the long term – as well as contracts awarded to regional companies during the development phase. The choice of site was made from the beginning in close dialogue with the municipality. The facility is being built out of direct sight of the town on a former mining heap; accompanying planting integrates it into the landscape, and compensatory measures promote the region's biodiversity.„In developing and realising this battery storage project, Zelos has shown that economic investment and municipal interests can be successfully combined,“ says Mayor Frank Ochsner. „It is particularly noteworthy that the pledged acceptance measures were taken into account and carried over even as the project was handed on to BW ESS. This is an important signal for the municipality and shows that Zelos does not merely develop projects but also takes responsibility towards the region and the people on the ground. The municipality of Klostermansfeld expressly thanks Zelos for its commitment, its reliable cooperation and its important contribution to the development of the Klostermansfeld energy park.“Energy-policy and infrastructural value
With the phase-out of coal and nuclear power, Germany will need close to 100 GW of installed storage capacity by 2030, according to industry estimates. Large-scale battery storage such as Van Gogh provides a central building block for this:• Integration of renewable energy: The storage system absorbs surplus wind and solar power and feeds it back in as needed. This balances fluctuating generation against actual demand and enables the further expansion of renewable capacity, reducing dependence on fossil imports.• Grid stability and security of supply: The facility provides capacity at peak-load times, stabilises the grid and strengthens the resilience of the electricity supply.• More efficient grid use: By managing grid congestion, the storage system reduces the need for costly and time-consuming grid expansion.• Strategic location: The site lies less than 200 metres from the Klostermansfeld substation, a central grid node in the 50Hertz control area. Across some 14.8 hectares, the facility is being built precisely where its grid-stabilising effect is greatest.„The groundbreaking for Van Gogh makes tangible what forward-looking project development can achieve,“ says Timo Juritsch, Managing Director of Zelos Energy Developments GmbH. „We see our contribution as turning complex site and grid potential into permittable, deliverable projects – and in some cases operating them ourselves. The conditions that came together here are rare. All the more, it delights us that Project Van Gogh is now being built as a supra-regional flagship project with technical relevance, regional roots and European resonance.“

Acquisition of 135 MW High Voltage BESS Project Monet from Zelos Energy by Prime Capital AG

Frankfurt / Berlin, 20.01.2026

Prime Capital expands German energy storage portfolio with 135 MW BESS acquisition from Zelos Energy Developments GmbH.• Prime Capital acquires 133 MW High Voltage Project Monet from Zelos Energy Developments in Saxony-Anhalt, on behalf of Prime Green Energy Infrastructure Fund II (PGEIF II).• The project is fully permitted, ready-to-build, with construction starting in early 2026.• The acquisition strengthens Prime Capital’s German battery storage portfolio and supports grid stability
and renewable integration.Prime Capital AG (“Prime Capital”) and Zelos Energy Developments GmbH today announce the acquisition of Project Monet, a 135 MW, 4-hour utility-scale battery energy storage system (BESS) located in Sachsen-Anhalt, in Northeast Germany. The project was acquired by Prime Capital on behalf of its Prime Green Energy Infrastructure Fund II S.A., SICAV-RAIF (PGEIF II) and is situated in the 50 Hertz TSO region.Project Monet has secured all key permits and is expected to reach ready-to-build status imminently. Construction is planned to commence in early 2026. The project has been developed in compliance with applicable environmental requirements and in close coordination with the local community.The acquisition strengthens Prime Capital’s battery storage portfolio in Germany, one of Europe’s most attractive and liquid power markets, and supports the continued expansion of flexible capacity essential to grid stability and the integration of renewable energy.
“This investment in Project Monet underscores our strong conviction in the critical role large-scale storage plays in the country’s energy transition. We are very pleased to partner with Zelos and to combine our expertise to deliver a landmark asset that will meaningfully enhance grid resilience and flexibility”, says Jens Walzner, Managing Director at Prime Capital.“With the sale of BESS Project Monet, Zelos Energy Developments reaches another market-relevant milestone in contributing to a sustainable and responsible energy system in Germany. We thank Prime Capital for a highly professional and partnership-driven transaction process and will continue to actively support the project’s realization”, said Timo Juritsch, Managing Director at Zelos Energy Developments.The deal was supported by CleanCap, acting as originator and investment advisor to Prime Capital. CleanCap will continue to support Prime Capital post-close on project management, procurement, tolling and debt financing. Legal advisors on the transaction included DLA Piper for Prime Capital and Brock Müller Ziegenbein and Terpitz Rechtsanwaltskanzlei for Zelos Energy Developments. Technical advisory was provided by Afry.

Large-Scale Battery Storage ‘Project van Gogh’ as One of the Largest Construction Projects in the Mansfeld-Südharz District (published by Municipality Klostermansfeld)

Klostermansfeld / Berlin, 16. Dezember 2025

Klostermansfeld experienced a real bombshell when it became known that one of the largest construction projects in the recent history of the Mansfeld-Südharz district will be realized in the municipality. A large-scale battery storage facility is to be built at the existing substation on federal road B 180—a project of Europe-wide significance.Mayor Frank Ochsner (independent) expressed great satisfaction about the impending start of the project: “We worked very intensively with the investors on this project for almost two years. I am all the more pleased that it is finally getting underway.”Once completed, the gigabattery being built in Klostermansfeld will have a storage capacity of nearly 6 gigawatt-hours (GWh). This is expected to make it the largest battery facility in Europe, capable of storing electricity for many millions of people and making a significant contribution to stabilizing the energy supply.With regard to site selection, a solution acceptable to the local population was also found. The battery facility will be constructed behind the small woodland near the Zirkelschacht and thus outside the direct line of sight of the Klostermansfeld residential area. In addition, it has been agreed to plant a green hedge along the railway line to visually frame the site. This will reduce the visual impact of the facility to a minimum.Addressing the economic importance for the municipality, Mayor Ochsner emphasized: “We have lived with the substation on the B 180 for decades. Unfortunately, however, we have not lived off it.”The transmission system operator 50Hertz, which operates parts of the substation, pays the majority of its business tax in Berlin. In the past, it was not possible to retain a larger share of these revenues locally.“All the more reason for me to be pleased that the operating company of the large-scale battery storage facility will establish its registered office here in Klostermansfeld. An office has already been rented. As a result, 100 percent of the business tax incurred will benefit our municipality in the future,” Ochsner continued.Projected business tax revenues are in the single-digit millions of euros, with a total investment volume at the Klostermansfeld site in the hundreds of millions. At the same time, the mayor urged objectivity: “I do not want to spread euphoria, but the forecasts very clearly show the potential this project has for our municipality.”Regional companies are already benefiting from the project. For example, the company Kutter from Helbra has been commissioned with preparatory measures, including archaeological investigations. Further earthworks and preparatory work have already been, and will continue to be, awarded to companies from the region. In addition, long-term jobs will be created, for example in the maintenance of green areas and the servicing of technical facilities. That not only Klostermansfeld but the entire region benefits from the project is also evident from the approval process: for the building permit, the Mansfeld-Südharz district collected one of the highest fees of recent years.In addition, there are voluntary community acceptance payments by the operators. These amount to several hundred thousand euros and are intended to benefit the municipality directly.“We will establish an association for this purpose, which will in future provide funds for social and cultural purposes, and in particular to support local clubs. This is very important to us, because it will allow us to move Klostermansfeld forward significantly,” Ochsner explained.
Looking back, the mayor drew a personal conclusion: “Two years of hard work lie behind us. There was hardly a week in which I did not deal intensively with this project—especially during the processing of the building permit by the district, the municipality was closely involved.”In conclusion, Ochsner underscored the long-term importance of the project: “The establishment of the gigabattery is a major success and a great opportunity for Klostermansfeld to develop in a future-proof way. Decisions on phasing out nuclear power and lignite were not made at the municipal level. But here we are creating the conditions for a secure energy supply—for today, for tomorrow, for our children and grandchildren. This project sets the course for generations.”

Public event in Klostermansfeld | Zelos presents the “Van Gogh” and “Monet” BESS battery projects in Klostermansfeld

Klostermansfeld / Berlin, 16. Dezember 2025

Zelos provided information on the planned Klostermansfeld battery park on 16 December during a public dialogue evening at the “Adolf Schnitzer” community center (5 - 7 p.m.).Numerous residents from Klostermansfeld and the surrounding area took the opportunity to gain an early overview of the project, its timeline, and the permitting process.The site comprises the two BESS projects “Van Gogh” and “Monet” and is designed for a total capacity of up to 1.15 GW and an energy capacity of up to 6.3 GWh. The facilities are intended to store surplus electricity from wind and solar power and feed it back into the grid as needed. In this way, the storage system stabilizes the power grid and provides relief during periods of high demand.“Transparent, early dialogue is important to us. We take questions and feedback seriously and incorporate them into the further planning,” says Timo Juritsch, Managing Director of Zelos.Press contact:
Timo Juritsch, [email protected], www.zelosdev.de

Zelos and BW ESS advance a 1.5 GW pipeline of battery energy storage projects in Germany

Berlin / Zürich, 16. April 2025

BW ESS and Zelos Energy Developments today announce that they are working on advancing a 1.5 GW portfolio of utility-scale battery energy storage system (BESS) projects in the federal states of Mecklenburg-Vorpommern and Sachsen-Anhalt in Northeast Germany. The projects are expected to achieve ready-to-build status in 2025-2027.The projects are strategically located in the 50 Hertz TSO region. In the partnership, Zelos will take the lead on securing land, grid, and permits. BW ESS will lead on engineering design and construction, global procurement, securing revenue, and project financing. The projects are being developed in close collaboration with local communities and following environmental, social and governance criteria. The partnership allows for further expansion as new opportunities arise.“Zelos is excited to partner with BW ESS in a collaboration that brings valuable experience and expertise to support our mission of realizing a substantial BESS pipeline in Germany. This partnership marks an important step as we jointly work to accelerate the energy transition and deliver impactful progress on the path toward a more sustainable energy future,” said Timo Juritsch, Managing Director, Zelos Energy Developments.“BW ESS is delighted to partner with Zelos. We continue to be impressed with their agility and speed. The expanded footprint in Germany reinforces BW ESS’ commitment to unlocking the value of energy storage”, said Roberto Jiménez, Executive Director, BW ESS.Germany is Europe’s largest and most liquid power market. It ranks among the top three most attractive European markets for BESS investment, alongside Italy and Great Britain. The federal government is updating its policies to support BESS including reviewing grid-related charges and permitting processes. It is also looking into the creation of a capacity market. A study by Frontier Economics states that the capacity of utility-scale BESS can generate €12 billion in added economic value. The German Solar Industry Association (BSW) projects that large-scale battery storage capacity could increase fivefold over the next two years, indicating a robust growth trajectory.For the transaction with Zelos, Bird & Bird acted as legal advisor and Arcadis acted as technical advisor for BW ESS. Legal counsel Mr. Jochen Terpitz acted as advisor to Zelos.Pressekontakt (Zelos Energy Developments):
Timo Juritsch, [email protected], www.zelosdev.dePressekontakt (BW ESS):
Hana Schoon, [email protected], www.bw-ess.com; Richard Matthews (Tamarindo), +44 (0)20 7100 1616, [email protected]

How Zelos Energy is powering Germany’s renewable future with Large-Scale Battery Storage

Berlin, 01. January 2025

In the transition to a clean energy future, reliable storage solutions are more critical than ever. Zelos Energy Developments GmbH, based in Berlin, is at the forefront of this transformation by developing utility-scale Battery Energy Storage Systems (BESS) that support a sustainable, responsible and renewable energy infrastructure.Battery storage systems are essential for balancing intermittent renewable energy — such as wind and solar — with real-world demand. These systems store surplus electricity during periods of low consumption and release it when demand peaks, helping stabilize the grid and reduce dependence on fossil fuels. With Germany planning to phase out nuclear and coal power, the need for large-scale energy storage is more urgent than ever. Experts estimate that nearly 100 GW of installed storage capacity will be required by 2030 to ensure continuous renewable energy supply.Zelos Energy’s project scope covers the full development lifecycle for BESS, from site analysis and planning to construction and commissioning. The company works closely with local authorities, grid operators and investors to secure land, grid connections and permits — streamlining the path to operational readiness.A notable milestone in Zelos’s journey is its partnership with BW ESS to co-develop a 1.5 GW portfolio of BESS projects in northeastern Germany. Under this collaboration, Zelos leads land acquisition and permitting efforts while BW ESS focuses on engineering design and construction. This cooperation marks a significant step toward realizing large-scale storage capacity that will strengthen regional energy security and support Germany’s renewable targets.As the energy landscape evolves, Zelos Energy continues to drive innovation in grid-scale battery deployment — helping communities adapt to a cleaner, more resilient power system.Pressekontakt: Timo Juritsch, [email protected], www.zelosdev.de