SOLAR CHARACTERISTIC ESTIMATION USING HARGREAVES-SAMANNI’S MODEL FOR NANDI COUNTY, KENYA

Abstract

Universal access to electricity is the current focus all over the world, especially in the developing countries where its biggest challenge is the provision of affordable and reliable electricity access for the majority without electricity today. Renewable energy technologies adoption by various players in the energy sector including consumers is critical in the transition process to a low- carbon driven economy and solar energy presents the best option in the fulfillment of this course. Solar energy variability is an impactful hurdle of concern in solar energy integration to the grid and as well as island mode source. Due to its varying and intermittent nature, an efficient use will require reliable forecasting of solar power. Intensity of solar radiation knowledge at a given location is beneficial for all solar energy conversion systems. Presented in this work the Hargreaves-Samanni’s model for estimating global solar radiation with data span of five years (2015-2019) using Kaiboi (longitude 0.42 N, latitude 35.03 E) as a case study. Statistical performance significance of the models was tested using the mean bias error (MBE), root mean square error (RMSE), mean percentage error (MPE) and R2. The result obtained showed that the mean solar radiation for the period is 478.7645 MJ.m-2.month-1 which highlight clear photovoltaic systems installation potential within the region for energy generation. The model represented well the observed values with smaller five year average MBE value of 0.015317.