A lighting system comprising: - a solar power generation section (1; 10-1 to 10-3); - -a first step-up circuit which is adapted to step up a first direct-current voltage generated by the solar power generation section to output a second direct-current voltage; - -a control section which is adapted to detect the first direct-current voltage, the second direct-current voltage and an input current of the first step-up circuit to control the first step-up circuit according to the result of the detection and is adapted to monitor an output power of the solar power generation section to acquire information on illuminance and direction of sunlight; - -a DC/AC conversion circuit which adapted to convert the second direct-current voltage into an alternating-current voltage; - -a switch board into which the alternating-current voltage is fed; - -an AC/DC conversion section which is adapted to convert the alternating-current voltage from the switchboard into a third direct-current voltage; - -a lighting device which is driven by the third direct-current voltage; and - -a lighting control section which controls illuminance of the lighting device according to the information on illuminance and direction of sunlight, wherein - the solar power generation further includes: - a plurality of solar cell panels facing different directions (10-1 to 10-3); and - a plurality of second step-up circuits (A2-1 to A2-3) each of which is adapted to step up a respective output voltage generated by the respective solar cell panel (10-1 to 10-3) to output the first direct-current voltage, and wherein - -the control section (44, 441) performs MPPT (Maximum Power Point Tracking) control so as to maximize output power of the solar cell according to the result of the detection by controlling the first step-up circuit, and - -the control section compares outputs of the plurality of solar cell panels to detect the illuminance and direction of the sunlight from a result of the comparison. - a solar power generation section (1; 10-1 to 10-3); - -a first step-up circuit which is adapted to step up a first direct-current voltage generated by the solar power generation section to output a second direct-current voltage; - -a control section which is adapted to detect the first direct-current voltage, the second direct-current voltage and an input current of the first step-up circuit to control the first step-up circuit according to the result of the detection and is adapted to monitor an output power of the solar power generation section to acquire information on illuminance and direction of sunlight; - -a DC/AC conversion circuit which adapted to convert the second direct-current voltage into an alternating-current voltage; - -a switch board into which the alternating-current voltage is fed; - -an AC/DC conversion section which is adapted to convert the alternating-current voltage from the switchboard into a third direct-current voltage; - -a lighting device which is driven by the third direct-current voltage; and - -a lighting control section which controls illuminance of the lighting device according to the information on illuminance and direction of sunlight, wherein - the solar power generation further includes: - a plurality of solar cell panels facing different directions (10-1 to 10-3); and - a plurality of second step-up circuits (A2-1 to A2-3) each of which is adapted to step up a respective output voltage generated by the respective solar cell panel (10-1 to 10-3) to output the first direct-current voltage, and wherein - -the control section (44, 441) performs MPPT (Maximum Power Point Tracking) control so as to maximize output power of the solar cell according to the result of the detection by controlling the first step-up circuit, and - -the control section compares outputs of the plurality of solar cell panels to detect the illuminance and direction of the sunlight from a result of the comparison. - a plurality of solar cell panels facing different directions (10-1 to 10-3); and - a plurality of second step-up circuits (A2-1 to A2-3) each of which is adapted to step up a respective output voltage generated by the respective solar cell panel (10-1 to 10-3) to output the first direct-current voltage, and wherein - -the control section (44, 441) performs MPPT (Maximum Power Point Tracking) control so as to maximize output power of the solar cell according to the result of the detection by controlling the first step-up circuit, and - -the control section compares outputs of the plurality of solar cell panels to detect the illuminance and direction of the sunlight from a result of the comparison.