Intelligent Power Saving System




Introduction: Intelligent Power Saving System

About: electronics hobbist

Intelligent power saving system is used to reduce the power loss in light systems. This efficiently uses the technology for proper controlling of light as we needed. Since it is an automated system, time can also be saved. The components required are PIR, LDR and BJTs and hence the circuit is simple and cheap...

Intelligent power system easily controls the input power and convert it into light as we needed
It will measure the intensity of light that already present in the room or veranda and control the light output as per our requirement. Since there is no need of extra light in the afternoon time and need more light at the night time, the system will take it into consideration and will automatically increase the intensity of light as the light in the room diminishes. Also the system uses a PIR section which can detect the presence of one who enters the room and hence the system is designed so that it will provide light only when someone enter the room and it will control the intensity of light as he required.

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Step 1: Components Required

Passive infrared sensor (PIR sensor)
LDR (light dependent resistor)
Transistor (BC547)
Resistor 470ohm; 1k;27k;47k;

Step 2: Circuit Diagram


In this circuit, we need light at the output only when there is the presence of a man at the room and the intensity of light in the room is very low. For this, the output of LDR section and PIR section is applied to a transistor. Hence the further working of circuit will occure only when both the inputs of transistor are high.
When the intensity of light at the room become less, due to the high resistance of LDR, the vcc applied will pass through the collector terminal of transistor Q1. To the collector of transistor Q5. The output from PIR is applied to Q5 base. Emitter terminal output is applied to the control section, containing transistors. Each transistor is designed to work at different votages such as 1volt,3 volt, and 5 volt. When the transistor Q2 switch on, it will make the path for LEDs at its output to complete and hence it will make the LEDs to glow.
As the voltage from LDR section increases, AND gate output voltage also increases which will make transistors Q3 and Q4 switch ON and the output LEDs will glow correspondingly. Thus when the light is low, complete LEDs will glow and we get a higher light. As the light in the room increases, the circuit output light decreases as we needed.


Solder all components on pcb or common circuit board

Step 4: Working

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    Nice. More people should have sensors on their lights. It saves a lot of energy.