Impact of Coastal Extreme Weather Stressors on Bifacial Floating-Based and Ground Solar PV Systems: Thermal Performance, Salt Crystallization and Dust Accumulation

Photovoltaic systems installed in coastal and arid areas are increasingly subjected to extreme environmental stressors such as salt-laden winds, high relative humidity, dust storms, and intense solar heating, which hasten soiling, salt crystallization, optical losses, corrosion risk, and performance degradation. This study provides a complete comparison of bifacial floating photovoltaic (FPV) and ground-mounted photovoltaic (GPV) systems operating in the same harsh coastal circumstances in Al-Khobar, Saudi Arabia. The power generation capability of both systems was experimentally monitored, and deposited dust and salt samples were collected from the front and rear surfaces of FPV modules and the front surface of GPV modules. An advanced characterization framework comprising scanning electron microscopy with energy-dispersive X-ray spectroscopy, Fourier-transform infrared spectroscopy, X-ray diffraction, and UV–Vis absorbance analysis was used to identify the morphology, elemental composition, functional groups, crystallinity, and optical behavior of the accumulated deposits. The FPV and GPV systems delivered peak power outputs of 466 W and 225 W, respectively, while the net daily electrical energy reached 1525 Wh/day for FPV and 903 Wh/day for GPV. Overall, FPV improved peak power output and net daily electrical energy by 107% and 68.88%, respectively. The results revealed distinct soiling mechanisms: sea-salt compounds such as NaCl, MgCl2, and CaSO4 dominated the FPV surfaces, whereas silicate-rich mineral dust and organic matter were more prevalent on GPV surfaces. FTIR analysis showed stronger carbonyl absorption at approximately 1720–1735 cm−1 on the FPV front surface, while stronger C–O stretching at approximately 1050–1120 cm−1 was observed for GPV deposits. XRD analysis revealed a high crystalline peak for the FPV front surface at 2θ ≈ 31.8°, with an intensity of approximately 45,600 a.u. and interlayer spacing of 2.81 Å, nearly seven times higher than that of GPV, confirming intense marine aerosol crystallization. The findings also reveal that FPV systems gain from improved power output under coastal conditions however face more salt crystallization and corrosion-related concerns, whereas GPV systems are more heavily influenced by dust adherence and optical shadowing. The study provides useful guidance for site-specific PV design, anti-soiling coatings, and corrosion-resistant materials for improving PV resilience under coastal extreme weather conditions.