Under the agreement, Metlen will be responsible for the engineering, procurement and construction (EPC) of the project, alongside energy management and commercial operations once the facility is commissioned.
The project will combine a 251.9MW PV plant with a battery energy storage system (BESS) totalling around 375MWh. Construction is scheduled to begin later this year, with commercial completion targeted for early 2028.
Evangelos Mytilineos, executive chairman of Metlen, said: “The formalisation of the launch of our partnership with Tsakos Group through the now joint SPV represents another substantial step towards the implementation of a highly significant investment for the Greek energy market. Large-scale hybrid projects, combining renewable power generation with storage, are at the core of the new energy system.”
The initial partnership deal was signed in January 2026 through a joint venture established to develop, construct, operate and commercially manage one of the largest hybrid renewable energy projects in Greece.
The joint venture was structured with Tsakos Group holding a 60% stake and Metlen owning the remaining 40%.
The project adds to Metlen’s growing portfolio of hybrid renewable energy assets, combining utility-scale solar generation with battery storage as Greece continues to expand renewable capacity while strengthening grid flexibility.
Financial terms of the transaction were not disclosed.
Metlen’s global renewable energy portfolio totals more than 11.9GW across various stages of development, including over 2.3GW of operational solar capacity and around 1.6GW of owned projects under construction.
In the UK and Ireland, the firm manages more than 90 completed or developing projects, including over 2.3GW of solar capacity across more than 65 sites and over 1.3GWh of energy storage.
Metlen also has a portfolio of around 3GW in Italy, while in Romania, it is developing the 211MW Monvallet solar portfolio with HELLENiQ ENERGY, with completion expected in 2026. In Chile, the company has delivered several solar-plus-storage projects before undertaking asset rotation activities.
Earlier this year, Metlen signed an agreement with Italian steel producer Acciaieria Arvedi to participate in Italy’s Energy Release 2.0 programme.
Under the arrangement, Metlen will develop 170MW of new solar PV capacity in Italy over three years, receiving a fixed tariff of €65/MWh from state-owned energy agency GSE. Acciaieria Arvedi will act as the offtaker, purchasing around 2.4TWh of generated electricity over the contract period.
https://www.pv-tech.org/metlen-tsakos-advance-251mw-greek-solar-plus-storage-project/
