Comparison of the representativeness of solar radiation type of days from the viewpoint of the production of parabolic trough and central receiver plants

Abstract

The classification of days according to the solar radiation features is one of the tools frequently used for the solar resource assessment, modelling or forecasting. Recent studies discuss the appropriate classification method or number of types of days, but these studies usually don’t take into account, at least in an explicit way, the relation between the types of days and the yield of solar plants. In this work, we compare the representativeness of the types of days defined by two classification methods from the viewpoint of the production of a Central Receiver (CR) and a Parabolic Trough (PT) solar plant. The selected classification methods are based on the daily solar radiation features: energy, variability and temporal distribution. So, in a first step, the days of a period of 16 years of measurements recorded in Seville (Spain) are classified by these two methods. In a second step, the daily gross productions of both CSP plants are estimated using System Advisor Model program. Then, the representativeness of the types of days of each classification method is evaluated according to the production of the CR and the PT plant by means of a methodology based on the clear sky yield index or kp index. Finally, the ARE and the annual relative RMSE and the MAE for the plants and classification methods analyzed are compared. Then, we can conclude, that the representativeness of the types of days of a classification method has a certain dependence on the plant that depends on the classification method applied.