Reliability-based analysis applied for reduction of cost of energy for offshore wind turbines

The vision is that the increased research on main wind turbine uncertainties and risk & reliability will lead to less conservative designs and more cost-efficient wind energy. Therefore, careful assessment of uncertainties for main wind turbine components is crucial because better knowledge on uncertainties and reduction of uncertainties imply cost reductions and/or higher reliabilities. Both cost reduction and higher reliability are essential in order that especially offshore wind turbines can become competitive compared to other energy supply techniques. All costs during the life-cycle of a wind turbine / wind farm should be accounted for. In this project three areas in the life-cycle with substantial uncertainties and costs are considered: foundation on soil or by floating devices, blades and operation & maintenance. These areas contribute significantly to the cost of a wind turbine and especially for offshore wind turbines they are important for the reliability and large cost reductions are potential. Thus, the general objective of the project is to establish a common statistical basis for the three areas. This includes identification and development of statistical models for the main uncertainties and defects related to strength and stiffness parameters (statistical and physical uncertainties) and to computational models (model uncertainties), and to quantify the uncertainties. Bayesian statistical methods will be used as a common basis to model spatial, uncertain distribution of strength parameters and defects in soil and blades, to assess the complicated, uncertain loading on floating wind turbines, and finally also for rational planning of operation and maintenance. Further, focus will be on investigation and development of methods to estimate the reliability of both wind turbine components and the whole wind turbine using this statistical basis