How does the presence of a strong temperature inversion layer near a solar power plant site influence the potential for soiling and dust accumulation on PV modules?

A temperature inversion layer is an atmospheric condition where temperature increases with altitude, instead of decreasing as is typical. This creates a stable atmospheric condition, trapping pollutants and particulate matter near the ground. The presence of a strong temperature inversion layer near a solar power plant site significantly increases the potential for soiling and dust accumulation on PV modules. Because the inversion layer traps air pollutants and dust, it prevents them from dispersing upwards, leading to higher concentrations of these particles in the air near the ground. These particles then settle on the surface of the PV modules, forming a layer of soiling. The stable atmospheric conditions associated with temperature inversions also tend to reduce wind speeds near the ground, further limiting the natural removal of dust and soiling by wind. The combination of increased particle concentrations and reduced wind speeds creates an ideal environment for soiling to accumulate on PV modules, reducing their power output. The frequency and strength of temperature inversions should be considered when developing cleaning schedules and estimating energy production for solar power plants.