From the producer certificate to energisation, a renewable or storage project in Greece ties up capital in more than one letter of guarantee, and each runs on its own clock. Here is which ones are required, how much they are, when they come back and when they are lost, with the provision behind each.
Last updated: · Also in Greek: Εγγυητικές επιστολές στην αδειοδότηση ΑΠΕ
| Guarantee | Amount | Return or forfeiture | Provision |
|---|---|---|---|
| Producer certificate | EUR 35,000 per MW of maximum generation capacity | returned when a complete request for a Final Connection Offer is filed | Law 4685/2020, art. 11A |
| Final Connection Offer | EUR 42, 21, 14 and 7 per kW by tranche; since 31.10.2024 30% is lodged (15% below 1 MW) | forfeited if not renewed in time, or if no connection contract takes effect while the offer is valid | Law 4951/2022, arts. 6 and 89A |
| Priority (ΑΔΜΗΕ groups Α, Β, Δ and Π9) | EUR 100,000 per MW | halved on the connection contract, returned on operation | ΥΠΕΝ/ΓΔΕ/84014/7123/2022, art. 6 |
| Bilateral agreement (Group Β) | EUR 100,000 per MW | forfeited if the signed agreement is not filed within 9 months of the offer | same decision, arts. 2 and 7 |
| Proper and timely performance, ΡΑΑΕΥ storage tenders | EUR 250,000, 150,000 and 200,000 per MW (first, second, third tender) | forfeited in full without a connection activation request by 15.12.2026 | Law 5233/2025, art. 43(1), as amended by Law 5338/2026 |
| Standalone storage, 2025 call | EUR 200,000 per MW above 10 MW, EUR 50,000 per MW up to 10 MW | the performance and operation guarantee is halved after 3 years of operation and returned after 6 | ΥΠΕΝ/ΓΔΕ/28255/1143/2025, as amended |
| Pumped storage with absolute priority | an additional guarantee, four times the art. 6 amount | 20% forfeited if the applicant withdraws | Law 4685/2020, art. 11Δ(9) |
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The first guarantee is needed before the project exists on paper. A producer certificate (Βεβαίωση Παραγωγού) or special projects certificate requires a "producer certificate letter of guarantee" of EUR 35,000 per MW of maximum generation capacity (Law 4685/2020, art. 11A(3), added by art. 137 of Law 4819/2021). It is part of the formal completeness of the application: a copy is filed with the application and the original reaches the licensing authority within five days (art. 11A(2)).
It is returned once a complete request for a Final Connection Offer is filed, with the operator's certificate of completeness. It is also returned at the holder's request, in which case the certificate lapses automatically, or at the applicant's request before the certificate is issued, in which case the application is rejected (art. 11A(5)). If the maximum capacity increases, so does the guarantee (art. 11A(4)).
The request for a Final Connection Offer (Οριστική Προσφορά Σύνδεσης) is filed with the competent operator together with the guarantee of art. 6 of Law 4951/2022. It is calculated in tranches per kW of requested capacity: EUR 42 for the part up to 1 MW, EUR 21 from 1 to 10 MW, EUR 14 from 10 to 100 MW and EUR 7 above 100 MW. For storage stations, the capacity is the maximum injection capacity (art. 6(3)).
Since 31 October 2024, however, only part of that amount is lodged: 30% for stations of 1 MW or more, 15% for smaller ones (Law 4951/2022, art. 89A(3), added by art. 37 of Law 5151/2024). For a 50 MW PV plant, for example, the scale gives EUR 791,000, so EUR 237,300 is lodged. For the same plant, the producer certificate guarantee is EUR 1,750,000, but that comes back as soon as the complete request is filed.
The guarantee runs for at least two years and is renewed until the readiness declaration, trial operation or energisation (art. 6(1)). It is forfeited to the RES Special Account in two cases: if it is not renewed at least three working days before it expires, or if no connection contract has taken effect while the Final Connection Offer is valid (art. 6(4)). Once the connection contract takes effect it drops to one quarter, and the rest is released within ten days of the readiness declaration or of the plant entering operation.
Exempt, among others, are local authorities, certain energy communities, stations on buildings and self-producers, and PV plants up to 1 MW in Western Macedonia and the Municipality of Megalopoli (art. 6(2)).
Anyone receiving an offer from ΑΔΜΗΕ through groups Α, Β, Δ or subgroup Π9 also lodges a priority guarantee of EUR 100,000 per MW of maximum generation or injection capacity (ΥΠΕΝ/ΓΔΕ/84014/7123/2022, art. 6). In groups Α, Δ and Π9 it is lodged on acceptance of the offer; in Group Β within nine months of its issue, extendable by three months if it is increased by 10% (as amended by Β΄ 4710/2025). It is halved when the connection contract takes effect and returned when the plant enters operation.
It is forfeited in the same cases as the art. 6 guarantee, and in two more: if the plant is not built within the term of its installation licence, or if no readiness declaration or operating licence application has been filed by the time the installation licence expires. The art. 6 guarantee remains due as well.
Group Β, which requires a bilateral power purchase agreement, also asks for a third guarantee, the bilateral agreement guarantee, again EUR 100,000 per MW (arts. 2 and 7). It is halved when the signed agreement is filed and, once the plant is in operation, reduced by 12.5% a year. It is forfeited, among other cases, if the agreement is not filed within the nine-month deadline. How the groups work is set out in the guide to the grid connection priority groups.
Stations selected in the ΡΑΑΕΥ storage support tenders lodge a letter of guarantee for proper and timely performance (Εγγυητική Επιστολή Έντεχνης και Έγκαιρης Εκτέλεσης) within three months of the final list of selected participants. The amount was set at EUR 250,000 per MW of maximum injection capacity in the first tender (Ε-45/2023), EUR 150,000 in the second (notice 2/2023) and EUR 200,000 in the third (Ε-240/2024). It is forfeited in full if the request to activate the connection is not lodged with ΑΔΜΗΕ, or is lodged after 15 December 2026; for the first and second tenders, the 30 June 2026 condition also applied (Law 5233/2025, art. 43(1), as replaced by art. 47 of Law 5338/2026). The details are in the battery storage permitting guide.
Standalone storage stations under the 2025 call follow a different scheme (ΥΠΕΝ/ΓΔΕ/28255/1143/2025, as amended by Β΄ 5165/2025). The application carried a guarantee to the Ministry of EUR 200,000 per MW for stations above 10 MW and EUR 50,000 per MW for smaller ones, or EUR 100,000 per MW for those up to 10 MW that filed no financing evidence. Once the offer is granted, a performance and operation guarantee in the same amounts replaces it; it is halved after the first three years of operation and returned after six.
For pumped storage, Law 5325/2026 provides examination with absolute priority up to 2,000 MW, against an additional guarantee four times the art. 6 amount. If the applicant withdraws, 20% of that guarantee is forfeited (Law 4685/2020, art. 11Δ(9)).
The law also provides for return without forfeiture. The art. 6 guarantee is returned on request, for example when a licence or approval the plant needs is suspended or annulled by a court (art. 6(6)). And when a project goes before a regional or central environmental licensing council and the opinion is negative, the certificate lapses, but the producer certificate and Final Connection Offer guarantees are returned (Law 4951/2022, art. 31A(5), as amended by Law 5299/2026).
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The art. 6 scale of Law 4951/2022 is EUR 42, 21, 14 and 7 per kW for the parts up to 1 MW, 1 to 10 MW, 10 to 100 MW and above 100 MW. Since 31 October 2024, 30% of that amount is lodged, or 15% for plants below 1 MW (art. 89A(3)).
Yes. It is returned once a complete request for a Final Connection Offer is filed (Law 4685/2020, art. 11A(5)).
If it is not renewed at least three working days before it expires, or if no connection contract takes effect while the offer is valid (Law 4951/2022, art. 6(4)).
Besides the art. 6 guarantee, the priority guarantee and the bilateral agreement guarantee, EUR 100,000 per MW each (ΥΠΕΝ/ΓΔΕ/84014/7123/2022, arts. 6 and 7).
By 15 December 2026 at the latest. After that date, or with no request at all, the proper and timely performance guarantee is forfeited in full.
This page summarises provisions for information and is not legal or technical advice for a specific project. The provisions were checked in the original gazette on 20 October 2026. Only the official publication in the Government Gazette, the decisions of ΡΑΑΕΥ and the operators' templates are authoritative. Amounts can change by ministerial decision, and each guarantee depends on the regime of the specific project.
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