Evaluation of Five-Direction Solar Irradiance in Urban Thailand

This study employed five-directional (North, South, East, West, and Horizontal) irradiance datasets to examine the variability, intermittency, availability, complementarity, and synergy of solar irradiance in Bangkok, Thailand. Irradiance from the North direction tends to have the lowest variability, whereas the South direction shows the highest variability. The results suggest that combining South roofs with East/West facades can smooth PV output across the day and provide late-afternoon support, while North facades offer secondary benefits under diffuse or seasonal conditions.