LONDON: Karatzis Group of Companies and METLEN (RIC: MTLN.L) have announced a strategic joint venture to develop a large-scale Battery Energy Storage System (BESS) in Thessaly, Greece. The project, designed to deliver 330 megawatts of power and 790 megawatt-hours of energy capacity, marks a significant step in bolstering Greece’s renewable energy infrastructure.
Under the terms of the agreement, Karatzis will hold a 51% stake in the venture, while METLEN will retain 49%. The partnership will oversee the full lifecycle of the BESS project—from development and construction to operations and energy management.
This will be the largest standalone storage unit planned to date in Greece and one of the biggest in Europe. The partnership builds on the existing cooperation between the two companies in the sale and absorption of green energy, which since August 2024 has involved the implementation of a portfolio of solar stations with a total capacity of 262MW in the same region.
The total investment for this project, which is expected to be completed within the second quarter of 2026, amounts to around €170Mio. No further grants or tax reliefs are expected for this project.
By investing in this pioneering project for the Greek energy market, METLEN undertakes the full construction, operation, and maintenance of the unit through M Renewables. The M Renewables segment of METLEN’s Energy Sector has proven experience in implementing complex energy storage (BESS) projects, with presence and projects on five continents. In 2024 alone, METLEN completed storage projects with a total capacity of ~0.7GWh and is in the final stages of agreements for third-party projects totaling 2.2GWh.
Through strategic partnerships such as this one with Karatzis Group with which it has had excellent cooperation in the last few years, METLEN reaffirms its leading role in strengthening energy security and advancing the green transition, building the next-generation Utility.
METLEN Energy & Metals PLC (METLEN or the Company) is the parent company of a multinational industrial and energy group and a leader in metallurgy and energy industries, focusing on sustainability and circular economy.
The company is primary listed on the London Stock Exchange with a secondary listing on the Athens Exchange, having a consolidated turnover and EBITDA of €5.68 billion and €1.08 billion, respectively, (2024).
METLEN’s group is a reference point for competitive green metallurgy at the European and global level, whilst operating only vertically integrated bauxite, alumina and primary aluminum production unit in the European Union (E.U.) with privately owned port facilities. In the energy sector, METLEN’s group offers comprehensive solutions, covering thermal and renewable energy projects, electricity distribution and trading, alongside investments in grid infrastructure, battery storage, and other green technologies.
Company’s group is active in the markets of all five continents, in more than 40 countries, adopting a full-scale synergetic model between the Metallurgy and Energy Sectors, while undertaking end-to-end development of major energy infrastructure projects.