A photocatalytic power generation system including a solar housing, a photoanode, an electrolyte membrane, a cathode, an oxygen diffusion membrane, and an external power generation circuit. The photoanode and the cathode are each positioned within the solar housing and electrically coupled to the external power generation circuit. The electrolyte membrane is positioned between and electrochemically engaged with the photoanode and the cathode forming a photocatalytic cell. The solar housing comprises a closed-loop water chamber having an anode side flow channel, a cathode side flow channel, a recombined water channel, and an oxygen diffusion membrane. Further, the oxygen diffusion membrane is positioned and configured to inhibit recombined water generated at the cathode from flowing from the cathode side to the anode side along the oxygen transport channel and permit recombined water generated at the cathode from flowing from the cathode side to the anode side along the recombined water channel.