Understanding the Effects of Heat Transfer on Snow Removal from Photovoltaic Modules

Snow accumulation on photovoltaic (PV) modules causes damage on them and significant financial losses by preventing their power generation. Here, snow removal mechanisms are studied under different heat transfer modes. A snowphobic coating (details of which is not provided) is developed and applied on small glass/aluminium surfaces mimicking PV modules to facilitate snow removal. Artificial snow with controlled liquid water content (LWC) is formed using a snow gun that mixes compressed air and water from a faucet. The LWC of the created snow is monitored using a surface-mountable sensor. The effects of free convection and shortwave radiation on snow removal are studied. Under free convection, the aluminium/glass surface with the coating allowed snow removal 25 hours earlier than the control bare sample. Under shortwave radiation, the coating resulted in 3 hours faster snow removal. Under a combination of convection and radiation, the coating allowed snow removal 3.5 hours earlier than the bare sample. Under outdoor natural snow conditions, the coating significantly improved snow removal by clearing snow off the PV module 10 days before the bare module. This study allows for developing a combination of active and passive strategies to facilitate snow removal from PV modules to maximize their power generation throughout the winter season.