Optimizing the Heat Sink for Concentrated Photovoltaic Systems for Different Heat Flux Conditions

Concentrated photovoltaic (CPV) technology has gained a lot of attention in the past few decades as researchers look to overcome the problems caused by conventional sources of energy. CPV technology uses low-cost optical concentrators to increase the solar radiation intensity on the photovoltaic cell, which then converts it to electricity due to the photovoltaic effect. The increased solar intensity causes the temperature of the cell to increase considerably, and hence heat sink becomes a must. In the present work, the central aim is to optimize the heat sink to be employed in the CPV system for various heat flux conditions. Firstly, micro-finned heat sinks of two different structures made of undoped silicon wafer are designed and numerically studied for Concentrator Standard Test Conditions (CSTCs) and Worst-Case Conditions (WCCs). The results obtained are compared with a square cross-section flat and finless base plate. Further, the study aims at finding the optimum arrangement for two CPV cells on a single heat sink under 2000,3000, and 4000 concentration ratios without comprising efficiency. Subsequently, the variation of heat transfer coefficient (HTC), maximum operating temperature of CPV cell, and mass-specific HTC with variation in height (H) of the fin to the space between the fins (S) are numerically analyzed in ANSYS 2022 R2. The mass-specific power of the circular-shaped heat sink is investigated to be highest, with a value of 327.41 W/kg. For the second case, the optimum distance between the two CPV cells arranged on a single heat sink was found to be 40 mm. The results also clearly suggest that the heat transfer coefficient significantly changes with the H/S ratio without significant changes in the mass-specific HTC.