Tuesday 31 July 2018

Load-out of first ‘jacket’ for TenneT offshore transformer platform.

The 55-metre-high substructure or ‘jacket’ for TenneT’s first offshore platform in the Borssele wind farm zone has been completed. The so-called ‘load-out’ of the jacket at the HSM Offshore shipyard in Schiedam is the first milestone for TenneT in the realization of the Borssele Offshore Wind Farm Zone project.

During the load-out, the jacket was loaded onto a sea-going barge using Self-Propelled Modular Transporters (SPMTs). The jacket was driven from the quay via steel planking onto the barge. This was a time-consuming job, because the ballast tanks of the barge had to be alternately filled and emptied to maintain stability during the loading procedure.

Sail away

On Sunday 5 August, the barge will be transported via the Nieuwe Waterweg canal to the Borssele I wind farm zone, where the jacket will be installed on the seabed by a crane vessel. Piles will be installed using hydraulic hammers, and a special type of cement will then be applied between the jacket and the piles in order to anchor the jacket in the seabed. These activities are scheduled for the period between 6 and 16 August.

The jacket is 55 metres high, 50 metres long and 28 metres wide, and weighs approx. 2730 tonnes.

Generating more wind energy

The Dutch National Energy Agreement (Nationaal Energieakkoord) stipulates that renewable energy sources must account for at least 16% of the overall Dutch electricity supply by 2023. To achieve this target, the Netherlands must generate more wind energy, both on land and at sea. The construction of an offshore electricity grid by TenneT plays an important role in this process. The National Energy Agreement also states that by 2023, wind farms with a total capacity of 3.5 gigawatt (GW) must be realized in three offshore zones: Borssele, Holland Coast (South) and Holland Coast (North). Together with the existing wind farms, this will result in a total generating capacity of approx. 4.5 GW. The Dutch government’s Follow-up Roadmap for Offshore Wind Energy calls for the realization of an additional 7 GW of offshore wind energy capacity by 2030, increasing the total installed capacity to 11.5 GW by that year.