Offshore wind power system economic evaluation framework under aleatory and epistemic uncertainty

Design and assessment of energy systems is affected by many sources of uncertainty and variability determining their technical and economic performances. This is even more relevant in systems exploiting renewable energy sources, given the intrinsic uncertainty in their availability. In this case, traditional design and evaluation methods based on deterministic analysis assuming average nominal values of involved parameters may lead to inaccurate decisions and underestimating inherent risk. Software tools for evaluating investment in renewable power systems are widespread, but uncertainty is often only included in the form of simple sensitivity analysis, changing one-element at time, thus failing to give a complete picture of uncertainty propagation effects. Some contributions on the economic evaluation of renewable energy systems under uncertainty are available in the literature, but only a few sources of uncertainty are considered. As a contribution to filling this gap, in this work, a framework for economic performance assessment of offshore wind power systems considering the effects of both epistemic and aleatory uncertainty is proposed by simultaneously considering the uncertainty of the correlations used to model the system, the variability of resource availability and energy sale price as well as the impact of failures and major disruptive events. The approach allows a thorough and realistic assessment of uncertainty propagation on the profitability of the investment, and is demonstrated in an accompanying application example.