Chemical reaction device

A method of operating a chemical reaction device, the method comprising:

• (1) determining presence of surplus power more than a demand;
• and
• (2) determining presence of solar energy,
• wherein:
• if it is determined in the determining (1) that the surplus power is not present, electrodes in an electrolytic cell are prohibited from being immersed in an electrolyte solution, and the chemical reaction device is caused to operate as a first system using electromotive force of a photovoltaic layer including a diode characteristic;
• and
• if it is determined in the determining (1) that the surplus power is present, the second step is performed so that, in an absence of the solar energy, the electrodes in the electrolytic cell are immersed in the electrolyte solution, and the chemical reaction device is caused to operate as a second system to generate chemical energy using the surplus power, and
• in the presence of the solar energy, the electrodes in the electrolytic cell are immersed in the electrolyte solution, and the chemical reaction device is caused to operate as a third system to generate chemical energy using the electromotive force of the photovoltaic layer.