251.9 MW Solar + 375 MWh Battery: METLEN-Tsakos JV to Build Greece's Biggest Hybrid

For Greece, a country targeting 80% renewable electricity by 2030, integrating storage with solar is crucial to manage the intermittency of weather-dependent generation. The METLEN-Tsakos hybrid project, with its 375 MWh battery capacity, directly addresses this challenge, providing a replicable model for large-scale clean energy infrastructure across Southern Europe.

METLEN and Tsakos Group have formalised a landmark partnership to develop one of Greece’s largest hybrid renewable energy projects, marking a significant milestone for the country’s clean energy transition. The joint venture, structured through a newly established Special Purpose Vehicle (SPV), will build a 251.9 MW photovoltaic power station coupled with a 375 MWh battery energy storage system in Central Greece. METLEN holds a 40% stake in the SPV, which will handle the full lifecycle of the project—development, construction, operation, and commercial management. The announcement signals the start of the implementation phase, moving the project from planning to tangible construction. This collaboration pairs METLEN’s deep expertise in large-scale energy infrastructure with the Tsakos Group’s financial strength and long-term investment philosophy, forging a union that extends beyond shipping into sustainable energy.

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METLEN holds a 40% stake in the SPV, which will handle the full lifecycle of the project—development, construction, operation, and commercial management.

The project’s design addresses a critical challenge in modern power systems: integrating intermittent renewable generation while maintaining grid stability. With 251.9 MW of solar PV and a storage system providing approximately 1.5 hours of discharge duration (375 MWh / 251.9 MW), the facility will shift solar generation to peak demand periods, reduce curtailment, and provide ancillary services. This hybrid configuration is becoming a benchmark for utility-scale renewables in Southern Europe, where solar penetration is rising rapidly. Greece, in particular, is targeting 80% renewable electricity by 2030 under its National Energy and Climate Plan, requiring a massive buildout of both generation and storage. This project aligns with that trajectory and could serve as a replicable model for other developers.

For METLEN, the deal reinforces its pivot towards energy transition assets. Already a diversified energy and metals conglomerate listed on the London Stock Exchange, the company has been expanding its renewables portfolio across Europe. Its Executive Chairman Evangelos Mytilineos underscored the strategic fit: “Large-scale hybrid projects, combining renewable power generation with storage, are at the core of the new energy system.” The 40% equity stake gives METLEN a meaningful economic interest while leveraging its project management and energy trading capabilities. For the Tsakos Group—best known for its global shipping operations via Tsakos Energy Navigation (TEN) Ltd.—the partnership represents a deliberate diversification into stable, long-term infrastructure. CEO Nikos Tsakos emphasized shared values and trust, signaling that the group views this as more than a financial investment but as a foundational step into the energy sector.