1. A monitoring system comprising:lighting equipment to be turned on by means of main power;
a remote control device configured to turn off the lighting equipment;
a battery configured to supply reserve power;
a sensor configured to perform predetermined measurement by means of the main power;
a detector configured to detect whether or not supply of the main power has been stopped by operation of a predetermined switch, and generate a detection result; and
a communicator configured to transmit the detection result by means of the reserve power in a case where the supply of the main power has been stopped.