Enhancement of photovoltaic module performance by thermal management using shape-stabilized PCM composites

Abstract

Thermal management of photovoltaic (PV) panels is crucial due to the deterioration of their electrical efficiency at elevated operating temperatures. Therefore, thermal protection of PV against overheating is highly required. This study investigated the applicability of the shape-stabilized phase change material (PCM) composites for temperature regulation of PV modules (PVM). Paraffin waxes (PW) with specific melting temperatures infiltrate graphite foam (GF) to prepare the GF_PW composite. The PCM composites are coated with expanded graphite-modified epoxy resin to prevent PW leakage after melting and to maintain product stability, integrity, and mechanical strength. The performance improvement of PVMs integrated with two types of GF_PW composites with different phase change temperatures of 35 and 44 °C (labeled RT35 and RT44, respectively) was studied. The adequate latent heat and thermal conductivity of the epoxy-coated GF_PW composites ranged from 126.5 to 138.1 J/g and from 2.03 to 2.15 W/m°C, respectively. The GF_RT44 and GF_RT35 composites, used as passive heat absorbing elements, reduced the PVM surface temperature by 27 and 32 °C, respectively, enhancing the PVM efficiency by 10.9 and 18.5 % of the reference configuration consisting of the PVM alone. To our knowledge, the PVM efficiency enhancement obtained in this study is the highest among PVMs integrated with PCM composites reported in the literature.