干旱区生态环境知识资源中心

Soiling and the resulting specular reflectivity are two of the most important factors influencing the efficiency of the concentrating solar power (CSP) plants. For this reason, and in order to schedule efficient cleaning cycles, it's crucial for the operation and maintenance (O&M) teams to possess accurate and readily available reflectivity measurements of the solar field, especially in periods with high aerosol concentrations.

The aim of this study is to, initially, evaluate the effect of dust on the reflectivity of regular CSP mirrors by means of two reflectometers used in operating power plants. Those mirrors were exposed at the University of Oujda (Eastern Morocco) for twelve weeks during the arid period of the year. After that, a comparison between the values measured by those devices has been done.

Results show that during the dry period, soiling presents an important issue for CSP power plants in Eastern Morocco, where the weekly reflectance drop can reach 30%. Furthermore, the accuracy of the reflectivity measurements and the selection of the most adequate reflectometer have an important influence on the estimation of the solar field's optical efficiency, thus, on the electricity production. (C) 2017 The Authors. Published by Elsevier Ltd.