The trial operation of the electricity connection between Crete and the mainland had to be cancelled due to bad weather, as the municipality of the island of Aegina did not grant permission for the construction of two necessary pylons.
The electricity connection between Crete and the mainland
The electricity link between Crete and Attica is nearly ready for full operation. Testing is moving along pretty fast and, so far, things are going well.
The last big test ran the connection from the Damasta high-voltage substation into Crete’s power system. It wrapped up smoothly, no hiccups.
More tests were on the calendar through April to make sure everything works before the official launch. The Damasta substation itself is a beast—biggest on Crete, with 17 gates and the latest closed-type tech.
It’s got digital control all the way and acts as the main link for Crete’s electrical grid to the new interconnection with Attica. Once all the equipment checks out, the team will move to operational trials.
This connection lets Crete plug into the wider Greek power grid. With the existing cable to the Peloponnese, Crete already covers about 30% of its electricity demand this way.
This interconnection is, honestly, one of the most ambitious energy transfer projects Greece has ever seen. The cost? Over €1.1 billion.
It uses some seriously advanced tech: bipolar direct current transmission (2×500 MW) and Voltage Source Converters (VSC) at the converter stations. A bunch of companies were involved—NEXANS, PRYSMIAN, and joint ventures like HELLENIC CABLES-NKT and SIEMENS-TERNA.
Contracts got handed out in 2019 and everyone signed on by mid-2020.
Technical Details
The system runs at a rated voltage of 525 kV and can push up to 1,000 MW of power. Both ends—Attica and Crete—use VSC tech for power conversion.
The Attica converter station sits near the old 400 kV Koumoundourou substation. It’s built to handle 2×500 MW, working in bipolar mode.
On the Crete side, the converter station connects at 150 kV. That’s where the underwater cable finally comes ashore, after running along the seabed between island and mainland.
Environmental and Energy Impact
This project plays a big role in Greece’s green transition. It helps boost renewable energy use and strengthens energy security by tying Crete more tightly to the mainland grid.
With less need for local fossil-fuel power, the environmental impact drops. Cable installation was planned with care to protect marine life, and the interconnection cuts Crete’s isolation, making it easier to balance electricity needs across regions.
Stakeholders and Management
The Greek Electricity Transmission Operator (ADMIE) is running the show, under its New Transmission Projects Division. There are a lot of partners and contractors in the mix, handling cable laying, building, and system integration.
Everyone’s working to make sure technical, environmental, and economic boxes are checked for EU and national rules. This helps with funding and keeps the project moving transparently.
Summary Table of Key Data
Aspect |
Detail |
---|---|
Voltage |
525 kV |
Power Capacity |
1,000 MW total (2×500 MW bipolar) |
Converter Technology |
Voltage Source Converter (VSC) |
Attica Station Voltage |
AC/DC at 400kV / 500kV |
Crete Station Voltage |
150 kV |
Project Cost |
Over €1.1 billion |
Key Contractors |
NEXANS, PRYSMIAN, HELLENIC CABLES-NKT, SIEMENS-TERNA |
Start of Contracts |
2019 (signed 2020) |
Expected Full Operation |
May 2025 |
The main power connection on Crete fails in windy conditions
The big Attica-to-Crete electrical link is running into trouble when it gets windy. Turns out, two simple poles that are needed for the system haven’t been installed because the local municipal authority in Aegina said no.
Without those poles, the electrical circuit can’t close properly. Not ideal, to say the least.
Testing for this billion-euro project was recently stopped in its tracks. Bad weather made it impossible for technicians to reach the tiny island where some essential cable equipment sits.
This equipment includes a key electrode—without it, Crete can’t get power through the cable. The cable system relies on two electrodes: one on the little island near Aegina, the other by Korakia in Crete.
These have to connect to medium-voltage networks on land to keep electricity flowing smoothly. The underwater cable between the island and Aegina is already in place, and most permits are sorted.
But the final go-ahead for the land cable and the two poles is still stuck with the Aegina municipality. The local government doesn’t want any poles, citing aesthetics—even though these aren’t for high-voltage lines.
No poles, no automatic function for the electrode on the island. That means if the wind picks up and these installations aren’t allowed, power to Crete could cut out more often than anyone wants to admit.
Key Points
Aspect |
Status |
---|---|
Total project cost |
Approximately €1 billion |
Cable connection locations |
Attica – Crete, via Aegina |
Critical poles required |
Two poles on Aegina (not high-voltage) |
Current municipality stance |
Denies permission for poles |
Effect of missing poles |
Electrode cannot function; risk of power outages during wind |
Recent tests |
Interrupted due to bad weather |
Permits obtained |
Yes, except final land cable and poles |
System Requirements for Operation
- Two electrodes must be connected to medium-voltage networks.
- Poles are necessary to support the land cable and enable the electrode on the island to work automatically.
- Testing and full function depend on local permissions allowing these installations.
The situation highlights a clash between what the big energy project needs and what locals want to see in their landscape. For now, the reliability of Crete’s electricity via this interconnection hangs in the balance, especially when the wind picks up.