Evaluation of uncertainty in PV project design: definition of scenarios and impact on energy yield predictions

In PV projects, it is important to understand how the variability and associated uncertainties of technical risks occurring during the planning phase are calculated and how the values are distributed in terms of probability. These aspects are essential for the calculation of the exceedance probability of the expected energy yield and how this is influenced by the overall uncertainty. A reduction in the uncertainties can lead to a higher values of energy yield for a given exceedance probability and hence a stronger business case. In this paper, the combined effect of uncertainties of various technical risks is calculated and discussed for several uncertainty scenarios and the impact is calculated in terms of exceedance probability (e.g. P90/P50 ratio).