Influence of material properties of liquid absorption filters for concentrated photovoltaic/thermal hybrid systems

A concentrated photovoltaic/thermal system with a liquid filter is an effective technique to utilize the whole solar spectrum for power production. However, fundamental issues still need further investigation, including the structure of flow design and absorptive fluid selection principles. This paper presents a comparative study of optimized configurations of fluid flow channels in a concentrated photovoltaic/thermal system. MATLAB was used to study the influence of fluid thermal properties and transmittance on the system performance. The results showed that increasing the ideality factor from 0.5 to 1 can improve the overall exergy efficiencies of the coupled and decoupled concentrated photovoltaic/thermal system by 2.2 % and 2.4 %, respectively. Moreover, it was found that the coupled concentrated photovoltaic/thermal is more suitable for electrical production when the heat capacity exceeds 2500 J/kgK. The coupled system's outlet temperature is boosted to 20˚C when the ideality factor is decreased by 20 % but requires significantly lower specific heat capacities. Overall energy efficiency tends to be higher at high heat capacity and low ideality factor values, while exergy efficiency tends to be higher at high heat capacity and high ideality factor values.