Crete’s electricity supply currently relies mainly on ageing fossil power plants that are due for retirement by the end of 2022, so the new power cable is needed to ensure the island’s supply security.
Under the turnkey contract, Siemens will design, supply and install two converter systems at a direct-current voltage of ± 500 kilovolts, as well as gas-insulated switchgear (GIS) substation on Crete. The two converters – one near Athens and the other near Damasta in north Crete – will be linked by a 330-kilometer-long direct-current (DC) power cable.
Transmitting green energy to Crete
Both stations will use HVDC Plus voltage-sourced converters in a modular multi-level arrangement (VSC-MMC) in order to convert alternating current (AC) to direct current and DC back to AC on the other side of the link. This allows Aridne to transmit energy from wind and solar PV, generated on the Greek mainland, to Crete which could help reduce emission by 500,000 tons in its first full year of operation.
“The system combines the advantages of HVDC transmission with benefits like AC voltage control, black-start capability, minimized power transmission losses, grid stabilization and high availability,” said Beatrix Natter, CEO of the Transmission Division at Siemens Energy.
The Greek construction company Terna will handle the installation of the HV distribution systems, carry out all civil works and equipment installations for the HVDC project.