Deltares was involved in the programme for the Borssele Wind Farm Zone at an early stage. In order to ensure the bidding process for the construction of the new wind farms is competitive, the Netherlands Enterprise Agency (RVO.nl) is collecting site data about the new wind farm zones. RVO.nl is an agency of the Ministry of Economic Affairs and is commissioning a range of studies. It will then make research results available to interested parties. Deltares has been involved in mapping out a large proportion of the site data relating to the Borssele Wind Farm Zone using a unique combination of technologies and models. For example, we identified the hydraulic boundary conditions (metocean conditions, such as wave heights and flow rates) using numerical models. During the same phase, we made forecasts of changes in the seabed due to mechanical forces exerted by currents and waves in Borssele throughout the lifetime of the future wind farm. This meant making extremely wide-ranging analyses of the data to describe changes in the seabed in recent decades. In that way, it is possible to determine, for example, the best locations for foundations or cables. Deltares was also involved during the tendering phase, helping different consortiums to use the data about the location and to optimise their specific projects.
In addition to the wind farms themselves an offshore power grid will be built. In the past, developers had responsibility for the grid connection linking their wind farms to the mainland, using long export cables; for the new wind zones, TenneT is responsible for grid connection and will build large offshore transformer platforms to which the wind farms can be connected. TenneT will be building two of these 'offshore sockets' in Borssele. For the stability of the foundations, it is important to know how much erosion ('scour') occurs in the bed around the foundations. Deltares simulated scour and the required protection in a scale model in one of its unique hydraulic facilities, the Atlantic Basin, so there will now be stable foundations throughout the lifetime of the wind farm.