Belgian transmission system operator Elia has issued two separate calls for bids, one for a detailed design of an offshore platform, and the other for an EPC contract for submarine cables that will link the company’s Modular Offshore Grid to the mainland infrastructure.
The OSY platform will be situated up to 45 kms offshore Belgian North Sea waters, Zeebrugge area, in water depths between 30m-35m.
The detailed design scope comprises but is not limited to a detailed design of a 4-leg substructure, piles, topsides, all relevant cable interfaces, platform process utilities, HV/LV Elia interfaces, 2nd layer grillage, load out interface, offshore transportation and installation interfaces, vendor equipment and suppliers interfaces, onshore and offshore commissioning, hook-up, and start up interfaces, all to ensure a fully completed project ready for startup.
The detailed design phase is scheduled for 2017, with onshore construction starting in 2018, and offshore construction in 2019.
The second call for tenders covers the design, testing, engineering, construction, supply, installation, burial, handling and commissioning of submarine 2 3-core 220KV AC power cables with integrated including all necessary accessories, such as joints and terminations.
The scope is a complete installed 3-core submarine cable system with integrated fibres for monitoring and communication purposes. After commissioning the tenderer can include operations, maintenance and repair. All provisions should be taken in order to install a RTTR (real time thermic rating system).
Elia estimates the total length 2 times +- 45 kms for the high voltage transmission. The lifespan of the cable system and installations should be 50 years.
Applications for the detailed design of the platform can be submitted until 1 August, while those interested in bidding for the EPC cable contract have until 31 July to do so.
The Modular Offshore Grid project is aimed at connecting offshore wind farms to a high-voltage substation located on the offshore platform, which will, in turn, be connected to the onshore grid.
In the long term, the modular grid infrastructure is planned to be connected to an international platform using direct-current connections, in order to transmit greater quantities of power over longer distances. Some of Belgium’s neighbouring countries, like the United Kingdom and the Netherlands, are also working to develop grids in their territorial waters in the North Sea.
These resources could be used in the event of there being insufficient wind in the North Sea. The connections will also allow wind power to be stored in dedicated infrastructure when a surplus of energy is generated.