The Influence of Photovoltaic Panels on Soil Temperature in the Gonghe Desert Area

Under the pressure of global warming and energy crisis, more and more attention has been paid to renewable energy, which promotes the rapid growth of global photovoltaic (PV) power plants. The construction of large-scale PV power plants changes the surface energy distribution, which inevitably affects the local microclimate and material exchange at the land surface. However, few studies have focused on the influence of large-scale PV power plants on soil heat exchange. Thus, this article studied the effects of two types of PV panels (fixed-tilt PV panels and oblique single-axis PV panels) on soil temperature in a desert climate area through field observations from September 2018 to August 2019. The result shows that PV panels cause seasonal and diurnal variations in soil temperature. Specifically, on a seasonal scale, PV panels have a warming effect up to 2.08°C during winter, but a cooling effect up to 4.15°C from spring to autumn. Furthermore, on a diurnal scale, PV panels have a warming effect on soil temperature during autumn and winter, but a cooling effect during spring and summer. The difference of soil temperature under PV panels was small under different weather conditions. In addition, air temperature, global radiation, and vapor pressure deficit were positively correlated with soil temperature, and global radiation has no direct effect on soil temperature under PV panels. We concluded that PV panels significantly changed soil temperature regime in desert areas, but their effects depended mainly on seasons.