Performance evaluation of a novel photovoltaic-electrochemic hybrid system

To harvest the relatively high wavelength sunlight, a novel hybrid system coupling a thermally regenerative electrochemical cycle to a dye-sensitized solar cell is proposed. Efficiencies and power outputs of dye-sensitized solar cell and thermally regenerative electrochemical cycle are calculated, and the mathematical relationship between the electric current of thermally regenerative electrochemical cycle and the working current density of dye-sensitized solar cell is deduced. The power output and efficiency of the hybrid system are also derived considering multiple irreversible losses. The feasibility and effectiveness of the proposed hybrid system will be assessed by comparing the performances between the hybrid system and the single dye-sensitized solar cell. Numerical calculations show that the maximum efficiency and power density of the hybrid system allow 32.04% and 32.18% greater than that of the single dye-sensitized solar cell, respectively. Comprehensive parametric studies are undertaken to examine the dependences of the hybrid system performance on some operating conditions and microstructure parameters, including electrode porosity, photoelectron absorption coefficient, Schottky barrier, film thickness and internal resistance of thermally regenerative electrochemical cycle. The derived results may offer new insights into design and optimization of such an actual hybrid system.