| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an exterior lighting system saving on energy by using solar battery and compensating for lack of a power supply with a commercial power source, using a small-sized and inexpensive electric double layer capacitor. <P>SOLUTION: This exterior lighting system is composed of the solar battery 5, the electric double layer capacitor 9, a commercial power supply line 12 for commercial power supply, a brightness sensor 6, and a switch circuit 11. The soar battery generates electric power smaller than the power which the illumination light consumes in one day. The electric double layer capacitor has electricity storage capacity which stores generated electric power of the solar battery, and supplies power which is equal to or smaller than the power the illumination light consumes in one day. This switch circuit supplies output current of the electric double layer capacitor to the illumination light when the brightness sensor detects that a measured value of surrounding brightness is less than a prescribed value and the storage power is the prescribed value or more, supplies the commercial power supply to the illumination light when the storage power is less than the prescribed value, and supplies no power to the illumination light when the measured value of the surrounding brightness detected by the brightness sensor is at the prescribed value or more. <P>COPYRIGHT: (C)2007,JPO&INPIT |
