Mitigation of Soiling by Vertical Mounting of Bifacial Modules

We experimentally explored vertical mounting of bifacial modules of different bifacialities for mitigating soiling in Mumbai, where the dust accumulation rate in terms of energy loss per day can be as much as 0.45%. Bifaciality is commonly referred to the ratio of the hack side value to the front side value of any of the performance parameters I-sc, P-max, or eta. The energy loss due to soiling in vertically mounted bifacial modules and monofacial and bifacial modules mounted at the latitude angle are compared. The experiments reveal that the vertically mounted bifacial modules have nearly zero soiling loss; bifacial modules mounted at latitude angle with 90% bifaciality have lower soiling rate; the energy yield of vertically mounted bifacial modules with 90% bifaciality can exceed that of bifacial modules mounted at latitude angle after three weeks if the modules are left to soil without cleaning; the peak temperature of operation of vertically mounted bifacial modules is seen to be 15 degrees C lower than that of bifacial modules mounted at latitude angle, implying potential benefits in long-term reliability and performance ratio; combining vertically mounted bifacial modules and bifacial modules mounted at latitude angle, a nearly flat, extended generation profile can be obtained.