A hybrid system consisting of dye-sensitized solar cell and absorption heat transformer for electricity production and heat upgrading

A new hybrid system mainly composed of a dye-sensitized solar cell (DSSC), a solar selective absorber (SSA) and an absorption heat transformer (AHT) is theoretically put forward to harness the long wavelength sunlight transmitted through the DSSC. The models of both DSSC and AHT are adopted from the current literature and the condition enables the AHT to involve in heat upgrading is obtained. The model validations of DSSC and AHT are conducted using experimental data. Mathematical expressions of power output and efficiency for the hybrid system are formulated by taking a variety of irreversible losses into account. The effectiveness of the hybrid system is justified and evaluated. Maximum power density (MPD) and maximum energy efficiency (MEE) of the integrated system are, respectively, 158.2 W m−2 and 16.3 %, having evidently improvement compared to that of a single DSSC. A variety of operating conditions and design parameters affecting the hybrid system performance are studied. Numerical calculation results show that the working temperature, photoelectron absorption coefficient of DSSC and total heat-transfer area of the AHT have positive effects on the hybrid system performance. There exists an optimum TiO2 thin film thickness to optimize the hybrid system performance. However, a greater Schottky barrier has negative influence on the hybrid system performance. The results obtained here may provide some guidance for designing such a practical hybrid system.