Performance evaluation for PV systems to synergistic influences of dust, wind and panel temperatures: Spectral insight

Dust is a ubiquitous occurrence influencing PV performance, primarily by cutting the solar radiation reaching the PV cell. Since the PV cell is always encapsulated, the dynamics of light reaching the cell involves a complex interplay of scattering, absorption and reflection of light starting from surface of glass till it reaches the cell. Dust settling on the glass adds to this complex interplay and alters the way both direct and diffused radiation reaches the PV cell. The impact of dust thus far has always been understood to be detrimental, which may not be valid under all conditions. Dust on PV (panel) glass could be studied as optical filters determining which wavelength of light reaches the PV cell. While few studies on dust have dealt with the spectral-band of light necessary for PV output, they have overlooked the fact that the remainder of the spectra is absorbed by the PV system, and could influence its output. It is possible that dust actually absorbs the unwanted IR that would otherwise increase cell temperature, degrading its output. Preliminary study concurs that certain kind of dust deposition at specific settlement densities could be beneficial for PV performance by absorbing unwanted IR. The current study deals with Si based PV which is known to predominantly operate on the visible part of the solar spectrum, and is easily affected by temperature (IR absorption) and dust.