Since photovoltaic (PV) panels are exposed to solar intensity long during the daytime, their
temperature increases significantly, which reduces their electrical efficiencies. This crucial factor
has led many studies to investigate various methods of cooling PV. The current study
experimentally analyzes the effectiveness of a new passive method to reduce PVs’ temperature
by using encapsulated phase change material (PCM) units placed on the PVs’ backsides. PCMs
have high latent heat and absorb/release huge amounts of thermal energy through
melting/solidification. Recent studies covered the PVs’ backside with PCM, while the current
study used PCM capsules instead. This new strategy lets the PV exchange heat the ambient when
PCM melt completely and improves cooling performance. An experimental setup was developed
for this aim, and it was tested outdoors in Bam, Iran, in late April and early May 2024, considering
two scenarios: PV with and without encapsulated PCM. The results proved that PCM units
reduced the PV temperature between 3 oC and 9 oC. This temperature reduction caused the PV
with PCM capsules to produce more electrical power by 17% compared to the conventional PV
at noon. The higher the electrical power generated, the higher the efficiency can be achieved in
the scenario with PCM units. The daily electrical efficiency of the PV with PCM units was 14.14%
higher than the conventional PV. This study illustrates that using encapsulated PCM units as a
passive method is a strong and affordable method to improve the PVs’ electrical efficiency.