Naupada, 19, India - While we walk out of a room having a 60W bulb without switching it off, the power wastage snow balls to approximately 22,000W per year. If this is the case of a single bulb what about the other appliances in our house hold.

My idea is to develop a electronic system which automatically turns ‘off’ and ‘on’ the appliances in a room. It works with cheap circuitry. What it does is very simple, it counts the number of persons entering a room then for the presence of a single person the lights in the room turn on. Then when a person comes out of the room the system deducts the number from the previously counted value. When the value becomes zero i.e. when no person is present in the room the light and appliances turn off automatically. This project finds itself useful not only in homes but also in schools,colleges etc.

Though this system is a complicated substitute to a simple turning off of the switches but it is essential because power consumption is a major factor contributing to the pollution, particularly in a nation where large amount of power is generated using fossil fuels. A unit prevented from wastage is equal to 1.5 units generated.

Circuit of system that automatically turns lights on/off