Automatic Illuminance Controlling System with Processing and Analyzing Unit for Energy Saving Purpose

Abstract

This paper presents the approach for energy saving in lighting system by controlling the
illumination in a classroom at a particular intensity automatically during 08.00 am. to 04.00 pm. based
on IES as a case study. The electric lighting used to compensate the natural daylight is obtained from
72 Watt fluorescents that are controlled by photo sensor as well as PID controller and PWM circuit.
Photo sensor will transform the illumination value as electrical signals to ADC circuit and then
transmit these data via RS-232 serial port to computer to create Visual Basic-based database. Finally,
the yearly average natural illuminance will be processed and analyzed. Moreover, the estimation of
electric lighting use in the future will be also calculated in order to control and reduce the electricity
cost.