SLOPE ANALYSIS OF CLOT-ADJUSTED SSI-FY4A DATA FOR SOLAR PV POWER POTENTIAL ASSESSMENT IN THE PHILIPPINES

Abstract. Utilization rate of energy from solar photovoltaic (PV) systems has surged considerably with the increase in global demand for sustainable energy solutions.The angle at which panels are positioned relative to the horizontal plane must be aligned with the sun's incoming radiation to achieve optimum power production. Unfortunately, this ideal alignment is not always feasible, particularly for panels lacking tracking systems. Therefore, determining the best tilt angle becomes a key factor that significantly influences the effectiveness of solar PV systems, considering various influencing factors. The study aims to establish the relationship between different slopes and solar PV performance and to assess the impact of this on energy generation efficiency for specific locations across Luzon and Mindanao. The study focuses on determining the optimal tilt for specific locations across Luzon, Visayas, and Mindanao. Sites including Metro Manila, Cebu, and Davao were selected as representative areas for each respective island group for being the most populous cities in their respective geographical island groups. Theoretical solar energy obtained from SSI was CLOT-adjusted and incorporated with dust and temperature effects to determine the maximum solar energy resource potential within the study area. Results show that the highest solar PV potential was determined at 5°–10° tilt angle for both Metro Manila and Davao followed by 10–20° and 20–30° tilt angle with an average of 86.42 W solar PV potential (PPV). For Cebu, the highest solar PV potential was determined at 20° to 30° tilt angle with the value of 95.99 W solar PV potential (PPV). The lowest PPV was found on installations with tilt > 30° in all the study areas at an average of 65.02 W. This suggests that to maximize solar PV output in different regions, installations should be tilted according to the optimal tilt angle specific to that region. The latitude differences across the country significantly impact which tilt angle is most effective, as they influence the amount of sunlight received in each area. To improve the accuracy of future studies, it is recommended to increase the number of data points per slope interval. While the differences observed in this study were small, having more data points can enhance the precision of average values obtained from formulas.