Dutch transmission systems operator TenneT has announced the start of construction of the DolWin epsilon offshore converter platform in Singapore.

The latest move follows the appointment of Aibel and Keppel FELS consortium for the development of the key elements of the DolWin5 offshore grid connection project last year.

Keppel FELS is responsible for the construction of approximately 80-meter long, 70-meter wide and 80-meter high steel structure of the DolWin epsilon offshore power converter platform at its shipyard in Singapore.

The 900MW DolWin5 high-voltage direct current (HVDC) transmission system will connect the Borkum Riffgrund 3 offshore wind farm off the coast of Lower Saxony with the extra-high voltage grid on land.

The wind power generated by the offshore wind farm at the sea will be transmitted in three-phase current to the DolWin epsilon converter platform.

TenneT said that the connection eliminates the need for substations at the offshore wind farms.

DolWin epsilon converts the three-phase electricity into direct current

The converter platform converts the three-phase electricity into direct current and will be sent it a total of 130km to the onshore converter station located in Emden/East.

In Emden/East the power received will be converted back into three-phase power and will be fed into the extra-high voltage grid through the converter station.

Upon completion of the construction work and installation of the technical equipment, the DolWin epsilon platform will be transported from Singapore to Haugesund, Norway for the installation of the converter and transformers.

As a subcontractor of Aibel and Keppel FELS, HITACHI ABB will deliver extra-high voltage direct current technology.

Furthermore, DolWin5 is scheduled to commence operations in 2024.