Damp‐heat induced degradation in photovoltaic modules manufactured with passivated emitter and rear contact solar cells

Abstract

Corrosion is one of the main PV module failure mechanisms, as it can cause severe electrical performance degradation in PV modules exposed to hot and humid environments. Moisture penetrating a photovoltaic (PV) module may react with the metallic components causing corrosion. In addition, acetic acid which is produced by hydrolysis of ethylene vinyl acetate (EVA), the most common encapsulant, may further degrade metallic components. Corrosion is one of the main PV module failure mechanisms, as it can cause severe electrical performance degradation in PV modules exposed to hot and humid environments. The specific chemical reactions involved in the corrosion mechanisms for the different components are well understood. However, which of these causes the most serious degradation in the field, and therefore, most severe power loss is unknown. Moreover, the severity of corrosion in the absence of acetic acid is not yet well researched. This work distinguished between the front and rear side corrosion mechanisms and identified the different electrical signatures observed due to them. The experiment included damp-heat (DH) conditioning of single-cell mini-modules, containing passivated emitter and rear contact (PERC) solar cells, laminated with a polyethylene terephthalate (PET) based backsheet. Furthermore, half-encapsulated PERC PV cells were tested, with either the front or the rear side exposed. Electrical and material characterisation were conducted for the investigation of the sample degradation, and the performance decrease, related to the degradation of the rear surface passivation, was examined.

Technical Evaluation of Photovoltaic Systems in the Bamenda Municipality of the North West Region of Cameroon

“…Placing panels directly on the roofs without enough aeration will lead to high heat. Te high heat and humidity will lead to faster degradation of the PV panels and materials which protect the cells [30][31][32]. It is therefore necessary to review the installation methods of SPVS in the Bamenda municipality in order to protect them from combine local heat and humid environment.…”

Investigation of Degradation of Solar Photovoltaics: A Review of Aging Factors, Impacts, and Future Directions toward Sustainable Energy Management

“…High temperature is a major cause of PV degradation. When a solar panel is exposed to high temperatures, it can cause several forms of damage that reduce the panel's efficiency and overall performance [28]. Some of the ways in which high temperatures can cause PV degradation include:…”

Performance and degradation analysis for different solar photovoltaic technologies under hot and humid environment: a review

“…Although the diffusion of hydrogen into the cell's bulk, which has already occurred due to the deposition of the rear-side passivation layer, is one of the most common causes, the exact mechanism of occurrence is still unknown. Under prolonged exposure to high temperature, V oc deterioration was detected, which most likely resulted from an increase in rear-surface recombination, which can occur even in the absence of light [29]. LeTID degradation may saturate and sometimes even recover during regular operation.…”