THE NEED OF FRAMELESS MOUNTING STRUCTURES FOR VERTICAL MOUNTING OF BIFACIAL PV MODULES

摘要

The vertically mounted bifacial modules (VMBM) allow attractive applications, for example as a complement for smoothing the power peak at noon time (getting 2 peaks of power: morning and afternoon). Studies [1-3] indicate that in specific places, VMBM can obtain better performance than conventionally mounted mono-facial modules (CMMM). In the present work, the relevance for choosing an adequate mounting structure for VMBM facing east-west in desert climate conditions is investigated to reduce the self-shading impact, on module power, to a minimum. Five 60 cell modules were installed in El Gouna, Egypt, and their IV curves measured every minute. Results indicate that the mounting frame shading effect can easily turn on the bypass diode, diminish the power output up to approx. 10%_(rel). The DSM anti-reflective coated glass improves the mean energy yield for the VMBM by at least (4.2±0.2)%. The soiling test demonstrates that VMBM are practically unaffected by dust accumulation for this specific desert location. Extrapolating the results to a 1 MW PV plant, the tilted mounted bifacial modules (TMBM) generates more energy than CMMM and VMBM but this last one has the chance to produce more net energy than CMMM if the soiling effect is considered.