A new model for computing monthly average daily diffuse radiation for Bangkok

A model for computing monthly average daily diffuse radiation for Bangkok Thailand was developed. The development of the model was based on the analysis of global and diffuse radiation data collected from four solar monitoring stations located at different parts of Bangkok, with the data collection period ranging from 4 to 8 years. The monthly average daily ambient temperature and relative humidity were also incorporated in the model. To evaluate its performance, the model was used to compute monthly average daily diffuse radiation of an independent data set. The model performed better than those found in the literatures.