Effects of Tilt Angle on Flat-Plate Solar Thermal Collector Systems

Aims: The performance of a solar collector is highly influenced by its orientation and its angle of tilt with the horizon. Both the orientation and tilt angle change the solar radiation reaching the surface of the collector. Previous studies show that south is the optimum orientation direction. By utilizing maximum solar energy through the optimum tilt, we are able to harness the energy needed without polluting our environment. It reduces the CO2 emissions in the atmosphere which is a major culprit for Global warming.
Study Design: In this study, the optimum tilt angle for the south facing single axis solar collector has been determined in order to maximize the system performance.
Place and Duration of Study: Department of Mechanical Engineering, Akdeniz University, 2014-2015.
Methodology: The equations which calculate total solar radiation falling on tilted surface for optimum tilt angle the monthly, the seasonally, the semi-annually, the annually, latitude ±15° and latitude are solved with a computer code which is written in MATLAB and should be modular to allow users to update component modules easily as new findings become available.
Results: The results convey that the optimum tilt angle changed between 1° (June) and 65° (December) throughout year in Antalya, Turkey. The loss in the amount of collected energy is around 1% if the angle of tilt is adjusted seasonally instead of using βopt for each month of the year.
Conclusion: Energy loss when using the yearly average fixed angle is approximately 7% compared with the monthly optimum tilt.