Determining Global Solar Radiation Incident on Tilted Surfaces with Different Tilt Angles at the Department of Physics Makerere University

KIRYA ROBERT KENT 141 PAGES (34365 WORDS) Physics Thesis

ABSTRACT Solar radiation data at horizontal level, tilted surfaces and in the atmosphere is an important feature in solar energy applications such as photovoltaic systems for electricity generation, solar collectors for heating and passive solar devices. This study presents an investigation of the dependence of global solar radiation incident on a tilted surface on some meteorological parameters for different tilt angles based on measured meteorological data of sunshine, relative humidity and temperature at Makerere University. Empirical models relating global solar radiation on tilted surfaces and meteorological data were formulated using data of six months. The proposed empirical model for the estimation of daily global solar radiation on the tilted surfaces assessment based on the statistical analysis with the Mean Bias and Root Mean Square difference that is in good agreement with the measured data on a tilted surface is = —0.2614 — 0.2386(RH) + 1.5822 (~~-~) + 0.1065 (~~) H0fl 65 Tmin In comparison with the other tilt angles the model yielded a RMSE of 4.2654, with a low (poor) correlation coefficient of 0.3743 at a 95% confidence interval and MBE of 1.5801. Analysis of data for a period of 3 years, towards the verification of Akoba’s (2009) model, the study recommends a new model = —0.9227 — 0.1405 (~) — 0.0335(RH) + 3.2826 (~2~) that capitulated a RMSE of H0fl N 65 2.5985, with a correlation coefficient of 0.8863 at a 95% confidence interval and MBE of 2.3391.