Northern Aegean Interconnection Phase B : Samos - Kos

On 26 February 2025, companies participating in IPTO’s final-phase tender for the submarine cable projects of the Dodecanese and North Aegean interconnections, including the Kos–Samos segment, submitted their binding financial and technical offers, after which the framework agreement award will be made based on the most economically advantageous bid.

In January 2025, IPTO commenced the final phase of its tender to conclude a framework agreement for the submarine cable projects of the Dodecanese and North Aegean electrical interconnections, under which the Kos–Samos interconnector cable will be procured.

IPTO reported that the marine surveys for both the Dodecanese and Northeast Aegean electrical interconnections were completed in December 2024; these surveys cover the submarine cable corridors for the wider island interconnection programme that includes the planned Kos–Samos (Samos–Kos) link under Phase B of the North Aegean Islands project.

In October 2024, Phase B of the framework-agreement tender for submarine cable interconnections of the Dodecanese and North Aegean projects, covering links such as Kos–Samos, advanced with the submission of technical and economic offers by contractors prequalified in Phase A, and this evaluation phase remains in progress.

By July 2024, Phase A of IPTO’s framework-agreement tender for the submarine cable interconnections of the Dodecanese and North Aegean projects, including the Kos–Samos link, was completed with the submission and assessment of participation applications from interested cable contractors.

In April 2024, IPTO launched Phase A of a framework-agreement tender by posting a call for expressions of interest for the submarine cable interconnections of the Dodecanese and North Aegean projects, a framework that covers cables for links including the planned Kos–Samos AC interconnector under the North Aegean Islands programme.

On 4 August 2023, IPTO published the preliminary Ten‑Year Network Development Plan 2023‑2032 for public consultation, which reconfirms the staged interconnection of the Dodecanese and the islands of the Northeast Aegean. According to this plan, the second phase, with a completion horizon in 2028, includes the Kos–Samos interconnection alongside Skyros–Evia, Lesvos–Chios and Rhodes–Karpathos, embedding the Northern Aegean Interconnection Phase B: Samos‑Kos within IPTO’s updated national network development strategy.

On 4 August 2023, IPTO published the preliminary TYNDP 2023‑2032 for public consultation, stating that by the end of the decade it will connect the Dodecanese and the islands of the Northeast Aegean as part of a new investment cycle with a combined budget of EUR 2.35 billion; the second phase of this programme explicitly includes the Kos–Samos interconnection, which covers the Samos–Kos project segment.

In a corporate presentation of IPTO’s Network Development Plan 2023‑2032 dated 21 November 2022, the "North Aegean Interconnection"—which includes the Kos–Samos (Samos–Kos) link under Phase B—is listed with an expected commissioning in 2029 and an updated total project cost of EUR 863 million.

By Decision No. 611/2021, issued on 29 July 2021 and later published in the Official Journal on 3 February 2022, the Regulatory Authority for Energy (RAE) approved the Hellenic Electricity Transmission System development plan for 2021‑2030, which mandates that the interconnections of the Dodecanese and the North Aegean Islands be completed by the second half of 2029. This regulatory approval provides overarching authorisation and timing guidance for the entire North Aegean interconnection programme, including the Phase B Samos–Kos link.

On 3 January 2020, IPTO announced that its preliminary Ten‑Year Network Development Plan (TYNDP) 2021‑2030 would, for the first time, include the interconnection of the North Aegean islands and the Dodecanese, a programme structured in three phases that explicitly covers the Phase B Kos–Samos 150 kV AC cable link. The plan allocates a budget of EUR 935 million for the North Aegean islands and EUR 1.477 billion for the Dodecanese, with Phase B—including the Kos–Samos interconnection targeted for completion in 2028—forming the basis for the Northern Aegean Interconnection Phase B: Samos‑Kos project.