The new 150 kV GIS onshore substation on Naxos, forming part of Phase B of the Cyclades interconnection, was inaugurated and commissioned on 13 October 2020 by IPTO, marking the electrical interconnection of Naxos to the mainland high‑voltage system. This commissioning enabled power from the mainland to be transmitted via the Naxos node through existing medium‑voltage submarine links to surrounding islands, including Koufonissi, upgrading their electricity supply with more reliable and lower‑cost power.
The Naxos–Koufonissi interconnection entered full commercial operation as part of the first stage of the Cyclades power interconnection, when, as of Thursday March 8, the islands of Naxos and Koufonissi began receiving electricity directly from the mainland grid via the new subsea cable system from Lavrio. This initial phase, developed and financed by the Independent Power Transmission Operator (ADMIE) at a cost of about 240 million euros, enabled indirect links from Paros to Naxos and onward to Koufonissi and other nearby islands, allowing local fuel-fired power plants to be shut down and placed on standby as the submarine cable network took over supply following electrification and testing.
Financing for Phase A of the Cyclades Interconnection, under which Naxos and Koufonissi are supplied from the mainland via Paros and Naxos, was structured as a €247 million investment co‑funded by the European Union and the NSRF and supported by a loan from the European Investment Bank. Of this budget, €102 million was provided as grants, while approximately €145 million is expected to enter IPTO’s Regulated Asset Base, reflecting the capitalised portion of the project costs.
| Cyclades | Cyclades | |
|---|---|---|
| Landfall | Naxos | Koufonisi |
| Grid Connection | Naxos 150 kV Substation | — |
Cyclades
Cyclades