Greek island Agios Efstratios generates 91 per cent of its power from renewables
The €7.23 million Ai Stratis – Green Island project combines wind, solar and battery storage, with surplus electricity also used for winter heating.
Renewable sources now provide 91 per cent of electricity on Agios Efstratios, a Greek island of 250 residents that previously relied entirely on fossil fuels. The EU-funded energy project avoids about a thousand tonnes of CO₂ emissions annually.
The island, also known as Ai Stratis, lies in the north-eastern Aegean Sea. Its renewable electricity reaches residents through the existing grid. Of the project's €7.23 million budget, EU Cohesion Policy financed 85 per cent, while Greek national funds covered 15 per cent.
Dimitrios Kardomateas, chairman and CEO of the Centre for Renewable Energy Sources and Savings (CRES), said the hybrid installation combines a 900-kW wind turbine with a 225-kW solar farm, battery storage and automated energy management operating in real time.
Manolis Klados, project manager at GEK TERNA Group, explained that the battery stores excess electricity and supplies power when renewable generation falls short. In winter, surplus generation also produces heat, which is held in four hot-water tanks with a combined volume of 500 cubic metres.
Installing the wind turbine involved transport and assembly challenges. However, Panagiotis Zorlos, project manager at CRES, said adapting Greek energy standards was the largest obstacle because the existing regulatory framework was too general for the pilot system's particular requirements.
