Greece is preparing a rapid expansion of electricity storage, aiming for 1.5 GW of operating battery capacity by mid-2027 and approximately 3 GW by the end of 2028. The programme is being developed through two parallel routes that cover different project configurations for grid connection.
Two parallel routes for battery and storage development
The first route focuses on standalone merchant batteries, with authorities evaluating proposals totalling 4.7 GW. A ranked list of eligible projects is expected in early September .
The second route covers renewable projects equipped with batteries behind a shared grid-connection point. Greek transmission system operator ADMIE is preparing final connection offers for approximately 2.5 GW of renewable and storage developments using this configuration.
Taken together, the two pipelines approach 7 GW and could generate investment of approximately €2.5 billion. Around 2 GW consists of batteries paired with clusters of solar projects.
Grid-access model introduced in late 2024
The model was introduced in late 2024 to improve utilisation of existing grid access and reduce the need for separate connections. Despite the change, many projects have remained delayed while awaiting formal approvals .
Greece currently has approximately 630 MW of battery capacity in operation. Around 530 MW comes from standalone projects financed through the Recovery and Resilience Facility, while another 100 MW is connected to the distribution network operated by DEDDIE.
The government expects the total to reach 1 GW by the end of 2026, before rising to 1.5 GW the following summer.
Operational assets and pumped-storage complement
Merchant projects are also beginning to enter operation. Early large-scale assets include the 330 MW Metlen–Karatzis Group project in Thessaly and Heron’s 162 MW installation in Viotia .
The battery build-out will complement TERNA Energy’s 680 MW Amfilochia pumped-storage project. When both technologies are included, Greece’s total storage capacity could approach 4 GW by the end of 2028.
Connection-offer speed as key delivery constraint
The central delivery risk is no longer project interest or available capital. It is the speed at which ADMIE can issue connection offers and define operating conditions for batteries sharing access with solar portfolios .
The outcome of those decisions will determine which part of the nominal 7 GW pipeline becomes financeable and reaches construction.
