A simple photoelectric conversion system for combustion gas enthalpy has been fabricated and tested. A cylindrical gaslight mantle is used as an enthalpy-light converter and two solar cells are used for photoelectric conversion. A methane-air premixed mixture is burned in a transparent silica-glass tube, where the gaslight mantle is installed. The maximum electric power of the cell unit was measured for varying flow rates of methane and air. The total conversion efficiency of the system was then estimated. It was found that the total conversion efficiency was not more than 1.5 x 10(-5). Several means to improve the present conversion system are suggested.