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Concerning about country’s energy situation which depends on the import mainly and Global Warming the world’s problem is also concern as well. So, this paper mentions a way to decrease the effect of those problems enhancing the energy efficiency in lighting system with an innovation using simple technology. After doing the energy conservation potential analysis of the original system, an automatic light dimming control using PI controller is the one in set of innovations will be developed. This control was designed using operational amplifier circuit and set PI gain using Ziegler-Nichols open-loop technique. This control has been installed and is being used in a classroom. With this control, the energy can be saved 6.36 kWh per month and the energy efficiency has been enhanced with the energy efficiency indicator 2.45 W/100 lx/m2 decreased from 2.61 the former level.
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