Metering method for saved illumination electricity

The invention relates to a metering method for the working time of an illumination device. Each lamp comprises a cumulative time control module with a cumulative time timer, a radio frequency identification tag with a memory and a power supply module. When the lamp is powered on, the cumulative time timer in the cumulative time control module starts to time cumulative time and timing data is written into the memory of the radio frequency identification tag; and when the lamp is turned off, the timer stops timing and goes on timing on the basis of the timing data timed at the previous time after the lamp is powered on at the next time. Time data stored in the radio frequency identification tag is the lighting-on time of the corresponding lamp. A wireless code reader is used to read the lighting-on time information stored in the memory of the radio frequency identification tag, the information is input into a computer for data analysis, and the cumulative lighting-on time of the lamp after times of opening and closing within certain time period and the consumed electricity within the time period are obtained. In the invention, since the light-on time of each lamp is independently timed and the metering accuracy is high; and since the time data is 'downloaded' through a wireless way, the operation is convenient and the efficiency is high.