A General Solar Radiation Estimation Model Using Ground Measured Meteorological Data in Sarawak, Malaysia

Abstract

Daily solar radiation is main fundamental for most of physical and living processes on the Earth’s surface as it plays role in the local and global energy budget. The data at specific location is quite indispensable for many solar energy related researches but not all places are equipped with such measured data collection. Solar radiation models based on meteorological parameters can serve as substitute to measured illuminance and irradiation data. This study is aimed to estimate the missing or incomplete data of solar radiation at meteorological stations in Sarawak using commonly measured meteorological data and selecting optimal models. Using the measured maximum and minimum air temperature differences, ΔT, relative humidity, RH and cloud factor, CF covering the years from 2010 to 2015, existing model are calibrated and new model is developed. The solar radiation is estimated by applying linear regression of ΔT, RH and multiple regression method (MRM). The result of calculation then is compared with the existing temperaturebased model namely Hargreaves-Samani model and BristowCampbell model using statistical performance. The result shows that over short and long term, MRM perform the best by giving small RMSE and MBE of close to 0%. Linear ΔT and RH gave considerable results of MBE less than 10% but vary in term of RMSE. BC model performance is quite similar to the performance of linear ΔT- K T model. The application of MRM model to the measured data is the best in predicting solar radiation data.