The Mean Hourly Global Radiation Prediction Models Investigation in Two Different Climate Regions in Morocco

Abstract

In last recent decades, Morocco gives increasing interest to developing renewable energy, by offering a wide range of investment opportunities in the sector of thermal solar energy. To establish such technology, predicting hourly radiation received during an average day of the month is mostly imperative. This paper proposes a statistical comparison between measured data of mean hourly global radiation at two different climate regions located in Morocco and three predicting models. This study is based upon statistical indicators which are root mean square error (RMSE), mean bias error (MBE) and correlation coefficient (R). It is attested that the Collares-Preira and Rabl correlation as modified by Gueymard (CPRG) fits more closely the measured data in this two regions at the West (Casablanca) and the East (Ouarzazate) sides of Atlas Mountains. Collares-Preira and Rabl model (CPR) gives practically the same result as CPRG but the correlation given by Whillier Liu and Joradan (WLJ) under-estimates the measured values at solar noon. 

Keywords

• Statistical study; hourly global radiation; tow Moroccan regions.

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