Performance evaluation of concentrator photovoltaic systems integrated with combined passive cooling techniques

Abstract

Enhancing the performance of concentrator photovoltaic cells integrated with passive heat sinks is essential. The objective of the present work is to boost the performance of combined fins and phase change materials (PCMs) as passive cooling for low concentrator photovoltaic systems during phase transition and after complete melting. Thus, a new passive heat sink is presented, including extended aluminum fins outside the PCM containeras a viable solution to elongate the PCM melting time and prevent temperature rise after the PCM completely melted.The developed design is compared with other different heat sinks such as fins, aluminum heat sink with PCM, andaluminum heat sink withfour parallel cavitiesfilled with PCM. A comprehensive two-dimension model for photovoltaic layers with integrated phase change material and extended fins is developed to predict the average solar cell temperature, conversion efficiency, and energy budget for each design at different concentration ratios. The model is numerically simulated and validated with the available experimental and numerical data. Results indicate thatthe use of PCM for passive cooling enhances solar cell thermal regulation during solid–liquid phase transition process due to latent heat absorption and maintains the solar cell temperature around 60 °C at concentration ratio of 5 suns. However, the PCM cooling capability is significantly reduced after the dissipation of its latent heat. At concentration ratio of 5, by using an aluminum heat sink with PCM, andwithfour parallel cavitiesfilled with PCM, the steady state solar cell temperature rises to 120 °C and 125 °C, respectively. However, the developed heat sink with extended aluminum fins outside the PCM container elongates the melting timeand prevents temperature rise after the PCM fully melted, sustaining a steady state temperature of around 82 °C. Accordingly, the new design of heat sink is able to maintain the steady state solar cell temperature below the maximum permissible temperature with the capability of storing thermal energy.