Review on the Sources of Power Loss in Monofacial and Bifacial Photovoltaic Technologies

Abstract

An evaluation of the degradation effects on photovoltaic modules is essential to minimise uncertainties in the system operation. Bifacial photovoltaic technology is attracting attention due to the capacity of generating energy from the front and rear sides. This paper presents a review of degradation factors, for both conventional monofacial and bifacial photovoltaic modules, to highlight how the current and voltage characteristics of these technologies are affected by degradation. Microcracking, encapsulant discoloration, and light induced degradation seem to have similar effects on both modules. Contrarily, bifacial modules are more prone to potential induced degradation as the electromagnetic shielding is affected by the bifaciality. Bifacial devices are less affected by light and elevated temperature induced degradation. The degradation (1.3%) is similar for both technologies, up to 40 kWh/m2 of solar radiation. Above this value, monofacial degradation increases faster, reaching values of 7%. For tilted systems, the front side soiling degradation of 0.30% per day is similar for both technologies. For vertical systems, soiling loss for bifacial is considerably lower with values of 0.02% per day.

Comparative analysis of grid-connected bifacial and standard mono-facial photovoltaic solar systems

“…The PV loss due to the temperature is the notable decrease of efficiency where the loss may be very high in hot climates [55]. Other array losses like the light-induced degradation, the module quality, the mismatch between modules and the ohmic wiring losses will decrease the array power further [58]. Finally, the array of virtual energy obtained at maximum power point (MPP) was given by 1700 MWh and 1544 MWh, available at the input of the bifacial and mono-facial inverter.…”

Energy Efficiency, Low Carbon Resources and Renewable Technology

“…Ref. [8] presented a review of degradation factors for both conventional monofacial and state-of-the-art bifacial photovoltaic modules in order to highlight how the current and voltage characteristics of these technologies are affected by degradation. Microcracking, encapsulant discoloration and light induced degradation seem to have similar effects on both modules.…”

Characterization of Dust on the Surface of Photovoltaic Panels in Low Latitude and High Altitude Plateau Areas

“…PV collectors frequently installed outdoors are greatly influenced by the environmental condition. Sometimes, the surface of PV arrays is coated by dust and other pollutants (also known as soiling) [3,4]. Another two critical factors also leading to the soiling phenomenon have been reported: installation features and weather conditions [5].…”