Adaptive observers for monitoring soiling rates in thermal solar collectors

Soiling represents one of the most important factors influencing the operation of solar concentrator fields. The cleaning cost represents an important percentage of the total maintenance cost for this type of installations. The estimation of soiling rates can be used to improve significantly the performance of the system by devising cost effective cleaning schedules. In this work, two adaptive observers are proposed to estimate soiling rates using available information in solar collector fields. Simulation results illustrate the main characteristic of each algorithms and their good performance under different operating conditions. Comments on how these encouraging results can be extended to deal with more complex scenarios are also provided. Keywords— Observers, solar concentrators, hyperbolic systems.