Jan De Nul connects Crete to Greek mainland

Photo courtesy of Jan De Nul.

CRETE-PELOPONNESE INTERCONNECTOR

FOR THE VERY FIRST TIME IN HISTORY, THE ISLAND OF CRETE HAS BEEN CONNECTED TO THE GREEK MAINLAND BY MEANS OF A SUBSEA ELECTRICITY LINK. A PROJECT COMMISSIONED BY GRID OPERATOR ADMIE AND AWARDED TO HELLENIC CABLES, IN WHICH JAN DE NUL GROUP INSTALLED THE 135KM LONG CABLE OVER A VERY CHALLENGING SEABED AT UP TO APPROXIMATELY 1,000M IN DEPTH.

Crete planned to connect to the Greek mainland to achieve a more reliable, cheaper, and environmentally-friendly electricity supply. The Crete-Peloponnese Interconnector is also known as the ‘Interconnecton of Records’: two submarine AC cables of about 135km each and 42km of underground AC cables on land connect Cretan Chania with Neapoli on the mainland.

Tobias Boderé, Project Manager at Jan De Nul Group, comments, “A challenging seabed

with rough rocks, 75t cable tensions, large water depths of up to 1km and the installaton of an unprecedented length of cable in very challenging adverse weather conditons: we have bridged these 135km all thanks to the treless eforts of our crew on board the Isaac Newton. Together, we successfully delivered the installaton of one of the most challenging interconnectors in the world.” Due to the proximity of the Hellenic Trench fault line, the

Image courtesy of ADMIE.

seabed between Crete and the Greek mainland is very rough with steep clifs. Jan De Nul installed several types of protectve material to protect the cable, ensuring its stability and durability. The cable route was optmised, and the diferent types of customised cable protecton systems (CPS) were successfully installed.

The interconnecton of Crete with the Peloponnese Peninsula consttutes the frst phase of the interconnecton of Crete with the Hellenic Electricity Transmission System (HETS). The new 150kV AC interconnecton (transmission capacity of 2x200MVA) is expected to enter trial operaton in the following period, transferring the frst electric loads to Crete. This frst interconnecton of Crete to the mainland will cover one third of the island’s energy needs, substtutng the producton of aged local power plants that are very costly and pollutng. The total cost of the fagship project, which amounted to USD 460 million, was co-fnanced by Greece and the European Union, as well as by loans from the European Investment Bank (EIB).

Upon the full interconnecton of Crete with the mainland system in 2023, when the planned interconnecton with Atca is to be completed, CO2 emissions of Crete’s power generaton will be reduced to zero, drastcally improving the island’s environmental footprint. The electrical interconnecton of Crete with Atca will be the frst HVDC interconnecton in the Mediterranean to use the most advanced converter technology of the Voltage Source Converter (VSC) type. The routng of this electrical interconnecton will start from Atca’s AD/DC converter staton, close to the Koumoundourou HVC. From there, two HVDC cables will be routed underground up to the landing point of Pachi, Megara. At Pachi, the two cables will be installed at sea and contnue their submarine route up to the landing point of Korakia in Crete.