Significant variations from one year to another. Variability of the wind resource over time. It is possible to identify two categories Quantification of uncertainties are crucial to determine the correct exceedance The applied methodology is subject to uncertainties. When evaluating the Net Yield, each step of Grid and BOP (Balance of Plant) availability Turbine availability and maintenance losses.According to the latest forecasting trends and best practices, we can identify losses as the following: The Net Yield figure derives from the Gross Yield, after taking into consideration the losses during the project lifetime. Utilising the theoretical power curve of the selected turbine model. Resource at each turbine location is converted into generation figures by Long-term forecast correction processes are used to derive an acceptable windĭistribution model over the life span of the wind farm. Land-based stations or mesoscale models provide the data. To create a wind forecasting model for the specific geographical area. As there is no accurate model to predict wind,Īnalysis over a short-term period is used in conjunction with historical data The P90 figure is the level of the annual generation that is predicted to be exceeded 90% over a year.Ĭrucial step consists the collection of on-site wind measurements over the The P50 figure is the annual average level of generation, where the output is forecasted to be exceeded 50% over a year. This article aims to simplify the terms and explain in plain English the difference between all the jargon, helping you to select the most appropriate figure when creating your revenue forecast and business model. Energy yield assessment studies are performed by wind experts to provide the Net Yield and exceedance probability figures, to mitigate that risk One of the critical risks when investing in the wind energy sector is the inconsistency of the wind resource compared to the forecast.

When you invest in wind energy assets, whether they are new or you acquire them on the secondary market you should be aware of two key figures which are critical for your forecasting and business plan assumptions these are P50 and P90. Co-Authors: Perrine Bugeat & Ypatios Moysiadis

P10 p50 p90 probability definition