Effective thermal management can significantly boost the photovoltaic module (PVM) performance due to the suppression of PVM temperature. In this paper, a thermally-driven thermocapacitive heat engine (TCHE) is proposed to harvest the long wavelengths of sunlight transmitted through PVM with the help of solar selective absorber for the aim of additional power production. The performance potentials of the conceptualized hybrid system are evaluated based on the models of PVM and TCHE considering multiple irreversible effects. Calculative results indicate that maximum power density and maximum energy efficiency of the PVM-TCHE hybrid system are, respectively, 38.74% and 38.56% higher than those of the single PVM, showing that TCHE is an effective thermal management approach for PVM. In addition, the influences of various design variables and operation conditions are studied to find clues for further improving the overall performance. Sensitivity analyses show that a larger operating temperature of PVM, diode ideality factor, ion concentration of electrolyte or charge cut-off voltage positively benefits the performance, while a larger ambient temperature or warm-up time worsens the performance. The charge during the charging process and discharging process can be optimally allocated.