Street lights are controlled manually in olden days. These days automation of street lights has emerged. But one can observe that there is no need of high intensity in peak hours i.e. when there is no traffic and even in early mornings. By reducing the intensity in these times, energy can be saved to some extent. There are many methods to save the power like Switching the street light on detecting vehicle , Street light controlling using LDR and relays etc. The proposed circuits controls street light intensity by calculating the peak hours.Two circuits are shown in this article,one explaining the street light control using ATmega8 and second explains street light controlling using PIC microcontroller. Most commonly found street lights are HID or High Intensity Discharge lamps, which consume a lot of power. In order to save energy, the circuits are designed with high intensity LEDs in place of HID lamps.
- ATmega8 micro controller
- DS1307 IC
- Light Dependent Resistor
- LED array.
- LCD display
How Auto Intensity Control of Street Lights Circuit Works?
- Initially power the circuit.
- Time is displayed on the LCD display.
- Place the LDR in darkness as the street lights switches on only when there is no light on LDR.
- Now check the time if the time is between 9 pm to 2 am street light glows with full intensity.
- From 2 pm intensity of the lights slowly starts decreasing and finally in early morning it glows with least intensity. When the light is sensed by the LDR lights are switched off automatically.
Limitations of this Circuit
- Even though energy is saved if there are any vehicles after fixed time, intensity of the light is low.
- Maximum energy cannot be saved.