The effect of upscaling and performance degradation on onshore wind turbine lifetime extension decision making

Ever greater rated wind turbine generators (WTGs) are reaching their end of design life in the near future. In addition, first approaches quantified the impact of long-term performance degradation of WTGs. As a consequence, this work is aimed at discussing and analysing the impact of upscaling and performance degradation on the economics of wind turbine lifetime extension. Findings reveal that the lifetime extension levelised cost of energy (LCOE2) of an 18 MW wind farm comprising of 0.5 MW rated WTGs are within the order of £23.52 per MWh. Alternatively, if the same wind farm consists of fewer 2 and 3 MW WTGs, the LCOE2 reduces to £16.56 and £15.95 per MWh, respectively. Further, findings reveal that an annual performance degradation of 1.6% (0.2%) increases LCOE2 by 34-41% (3.6-4.3%).