A ministry ranking list due in October reads like paperwork. What it’s actually deciding is which sliver of a wildly oversubscribed queue gets to exist.
Greece’s Ministry of Environment and Energy is putting the finishing touches on priority lists for its third and largest push into standalone battery storage: a 4.7 GW call for “merchant” batteries — projects that earn revenue purely by trading power, with no state-guaranteed payment. The ministry’s evaluation committee has essentially completed its assessment, with only final checks left before the rankings are locked in; a Ministerial Decision approving them is expected in October. It will follow three earlier tenders that together secured roughly 900 MW of supported projects, of which 309 MW is already in trial operation and a further 401 MW is built and awaiting final steps. Total installed battery capacity in Greece, including plants converted from old thermal-unit licences, stands at around 700 MW today.
The 4.7 GW call itself is heavily oversubscribed, but not uniformly. On the transmission side, where Greece’s grid operator IPTO can offer 3.8 GW of connection capacity, bids came in around 8 GW — better than two-to-one. The distribution network, run by DEDDIE/HEDNO, has just 900 MW on offer against roughly 1 GW of applications, a far tighter squeeze. Both figures are already down from where they started: when applications first came in during March, the program drew 12.2 GW of bids against the same 4.7 GW ceiling, before incomplete or ineligible submissions were filtered out in the months since.
Even that narrower number understates how lopsided Greece’s storage pipeline has become. The energy regulator, RAAEY, has issued roughly 1,600 storage generation licences nationwide with a combined approved injection capacity of 67.54 GW and guaranteed storage capability of 254.33 GWh — more than fourteen times the capacity this connection round can accommodate, and well past Greece’s own revised 2030 national storage target of 5–7 GW, itself raised this year from an earlier 4.325 GW goal. Most of that licensed 67 GW was never going to be built; the tender and connection process is the mechanism by which the vast majority of it gets quietly eliminated.
That elimination is already visible in the license register, separately from the tender rankings. RAAEY recently revoked licences covering about 2 GW of storage projects whose developers missed deadlines to apply for Final Connection Offers — treated by the regulator as proof the projects had never matured past paperwork. Thessaly lost the most, roughly 925 MW concentrated around Larissa and Trikala, followed by more than 600 MW in Eastern Macedonia–Thrace near Rodopi and Komotini. In other words, most license-holders aren’t losing out in a dramatic ranking battle; they’re being quietly struck off for missing procedural deadlines long before they’d ever reach a connection queue.
The pressure behind all of this is Greece’s curtailment problem, which has gone from a rounding error to a genuine financial threat to solar owners in about two years. Curtailed renewable output rose from 900 GWh in 2024 to roughly 2 TWh across 2025, and Greece had already lost an estimated 1.3 TWh more in just the first five months of 2026. Industry figures have put curtailment above 15% of potential output in the first eight months of 2025, concentrated in the midday hours when solar output peaks, with projections that it could reach 30–35% in 2026 without meaningfully more storage online. The head of Greece’s PV producers’ association has warned that without new storage capacity coming online soon, escalating curtailment will push “thousands of small solar PV investors into bankruptcy” — the stakes behind an otherwise bureaucratic-sounding tender announcement.
A separate, faster-moving track is running in parallel: “collaborative batteries,” installed at the shared connection point of existing solar clusters rather than as new stand-alone sites. IPTO has been legally instructed to process these applications — roughly 800 of them are currently under review — with absolute priority until a combined 1,000 MW of Final Connection Offers has been issued; more than 500 MW has been granted so far, and the government is targeting completion of that tranche within weeks.
That distinction matters: a connection offer is a legal right to connect, not a working battery. Greece’s operational total, still around 700 MW, is the number that actually reduces curtailment, and the government’s own near-term goal is to get that to roughly 1 GW by the end of 2026. Only once the collaborative-battery tranche is finished does the ministry plan to start allocating the first 1 GW slice of the 4.7 GW merchant call — meaning the October ranking decides who is next in line, not who connects next.
The money lining up behind all this is substantial and increasingly corporate. Metlen, partnered with the Karatzi Group, is building what would be Greece’s largest single storage unit — 330 MW / 790 MWh in Thessaly. DEI (Public Power Corporation) is targeting 1.44 GW of battery capacity by 2028. GEK TERNA and the Copelouzos Group’s ELICA, which alone holds roughly 775 MW in licences across five sites, are both building multi-project portfolios.
Unlike the 900 MW awarded in the first three tenders — which came with fixed annual remuneration reported between roughly €44,100 and €49,917 per MW — the new 4.7 GW batch carries no state-backed payment at all. Ranking well in October doesn’t guarantee a subsidy; it guarantees only the right to compete for revenue in Greece’s power market. Given that roughly 60 GW of licensed capacity will never get that chance, it’s a right worth a great deal.
