Design and analysis of the foundation and anchoring systems of offshore wind turbine platforms for the southern Baltic

The main objectives of the Wind-Tu-Pla project (NFR- 221290) is to work out the design, handling and economical aspects of offshore wind turbine platforms for use in the southern Baltic Sea, in the Polish economical zone. Poland has an old-fashioned dirty energy production with use of significant amounts of hard coal and low production of renewable energy. This project is holistic, it takes up all aspects from combined environmental measurements and mathematical modelling to find worst-case hydrological and meteorological scenarios to the platform design, construction, installation, maintenance and environmental measurements after installation. There is significant innovation, on platform design and sensor technology, and involvement of industrial organisations in the project that has four partners: Gdansk University of Technology (coordinator), Nauta Shipyard (Poland), NIVA (Norway) and Aanderaa (Norway). Six different field measurements systems were used including monitoring of winds, currents and waves. The NIVA adapted GEMSS model was operated to find worst-case hydrological (8.5 m waves with a 10.4 s period) and meteorological (winds of 44 m/s 90 m above the sea surface) scenarios to design the platforms. Statistical treatment of historical wind data demonstrates a good potential for wind power with the majority of winds from 10-16 m/s in the area. Two platform designs were selected: a floating Tension Leg Platform (TLP) and a Spar type. Several versions of these designs were model simulated with Computational Fluid Dynamics (CFD) and two scaled platforms were built and run in real basin tests for calibration and verification of the model runs. The forces on the tension legs and the construction were taken into account when making construction drawings that is the base for calculating construction, installation and maintenance costs using the Nauta shipyard in Gdynia as the base.?

The main objective of the proposed project is to work out the design, handling and economical aspects of offshore wind turbine platforms for use in the southern Baltic Sea, within the Polish economical zone. The design will be based on existing concepts u pdated with technical developments that are particularly adapted to the suggested deployment areas. Within the project two different types of platforms will be developed one for waters shallower than 40 m and the other for waters deeper than 40m. The pro posed project is divided into 6 work packages WP1:Coordination; WP2: Environmental parameters (wind/waves/currents); WP3: Platform design; WP4: Anchoring and foundation design; WP5: Transport and installation procedures; WP6: Economical aspects. From the Norwegian side two organizations will be involved in the project these are Aanderaa Data Instruments (AADI) and the Norwegian Institute for Water Research (NIVA). These organizations will mainly work in WP2 which deals with mapping and prediction of norm al and worst case scenarios for hydro-meteorological conditions (currents, waves and wind). Simple bottom topography mapping and sediment investigations, to deduct anchoring conditions, will be conducted in selected areas. In addition we will investigate and propose the most efficient way to integrate monitoring systems to the wind turbine platforms, so that these can serve the additional task of environmental monitoring. Use of these data will help to improve navigational safety, to track chemical spi lls if these occur and for biochemical measurements, of particular interest in the Baltic Sea which is suffering from oxygen depletion, eutrophication and large blooms (of e.g. toxic cyanobacteria).