Felix A. Uba and Emmanuel A. Sarsah
Tilt angle greatly influences the performance of solar collectors. Maximum output can be obtained by solar collectors if they are installed at an optimum tilt. In this study, a mathematical model is used to determine the solar radiation incident on an inclined surface and the optimum slope angles for each month, season and year are calculated for solar collectors at Wa, Upper West Region, Ghana. The calculations are based on the measured values of monthly mean daily global radiation and estimated diffuse solar radiation on a horizontal surface. It was found that the optimum tilt is different for each month of the year. A computer program in MATLAB software was developed for this purpose. The collected energy on the inclined collector is simulated as the tilt angle is varied. In this study the collector surface is assumed to be facing towards the equator. The yearly average fixed tilt angle is found to be 26.8° for the location (i.e. the latitude of Wa plus 17°). The maximum solar energy gains are 212.41MJ/m2 and 211.461MJ/m2 when using the yearly average fixed angle and seasonally adjusted tilt angle representing a loss of 1% and 0.6% respectively compared to the monthly optimum tilt
