Design And Construction Of An Automatic Office Solar Light Using Pir Sensor

CHAPTER ONE

1.0                                                        INTRODUCTION

Nowadays without electricity we cannot imagine our daily life because electricity has become a necessity for all, without which day-to-day life chores and daily activities become stand still. Due to the depletion of non-renewable resources, conservation of energy has become mandatory and by doing so we can reduce electricity bills as well. We know that energies like wind energy, solar energy and hydro energy are called renewable energy sources which are renewable in nature. Therefore, utilization of these resources for power supply is the best possible way of producing, conserving and renewing energy, which is advantageous as it is pollution free, affordable, and free from environmental impacts.

On the other hand, the energy resources like petroleum, coal, natural gas, uranium and propane are called non -renewable resources, because their supplies are limited. Many environmental effects and day-by-day depleting energy resources warn us to save energy by using automatic room controller and energy-efficient lighting systems. Nowadays the wastage of electricity has become a routine thing for us, and the problem has become frequent at homes, schools, and colleges and even in industries. Sometimes we notice fans and lights keep on working even in the absence of people. This often happens in homes, offices and public places due to utter negligence of the inmates.

However, there is a solution to control energy efficient lights in offices by using automatic office light controller. This work provides information about such a solution of energy efficient lighting to conserve energy by optimizing office appliances such as lights using solar energy and passive infrared sensor.

When one enter an office, as a habitual tendency, the person often search for a switch to turn the light on, and if person is new to the office, will often find it difficult to locate the switch. Most of the times, many of us forget to switch off the lights while leaving the office in which we stay most of the time. This results in unnecessary power wastage. Therefore, an automatic office solar light controller automatically turns on the lights and the light remain ON when a person enters into a office and in the office, and turns off the lights when the person leaves the office.

1.2                                             OBJECTIVE OF THE PROJECT

The objective of this work is to design and construct a device that will automatically turns on the lights and the light remain ON when a person enters into a office and in the office, and turns off the lights when the person leaves the office.

1.3                                         SIGNIFICANCE OF THE PROJECT

The significant thing about this work is that it exposes student on how to illuminate our office automatically during power supply and power outage, how rechargeable batteries and solar panel works.

1.4                                                 SCOPE OF THE PROJECT

This work makes use of passive infrared as the sensing device. Infrared band of the electromagnet corresponds to 430THz to 300GHz and a wavelength of 980nm. The propagation of light waves in this band can be used for a communication system of data. This communication can be between two portable devices or between a portable device and a fixed device.

The transmitter of an IR LED inside its circuit, which emits infrared light for every electric pulse given to it. This pulse is generated as a button on the remote is pressed, thus completing the circuit, providing bias to the LED.

The LED on being biased emits light of the wavelength of 940nm as a series of pulses, corresponding to the button pressed. However since along with the IR LED many other sources of infrared light such as us human beings, light bulbs, sun, etc, the transmitted information can be interfered. A solution to this problem is by modulation. The transmitted signal is modulated using a carrier frequency of 38 KHz. The IR LED is made to oscillate at this frequency for the time duration of the pulse. The information or the light signals are pulse width modulated and are contained in the 38 KHz frequency.

1.5                                              BENEFITS OF THE PROJECT

• For most people the biggest challenge in using Solar power at home is to have space to install the solar panels. Especially people living in apartment complexes find it hard to get space for it. The best thing about automatic office solar lighting system is the small size of solar panels because it powers LED Lamps

• Automatic office solar lighting system is portable and lightweight.

• With 8 to 12 hours of charging these lights run for 4-100 hours depending on the brightness it is kept at. Hours of operation are low for high brightness and high for low brightness.

• The maximum amount of light or brightness produced is equivalent to a 5 Watt CFL that is sufficient to create visibility in a regular office.

• Can even be used for precision work during power cuts. Just that one has to sit closer to the light.

• The solar panels and LEDs last for long (about 48hrs of usage). The only regular change needed is for the batteries.

1.7                                              STATEMENT OF PROBLEM

The most obvious of course is that if it’s a cloudy or overcast day, automatic light isn’t going to be able to garner the energy it needs from the sun in order to function. Usually, it needs direct sun in order to store enough in the battery to work efficiently.

Another problem to the device is that the amount of power they are capable of generating isn’t always enough to keep up with the amount of power required by today’s highly functional cell phones.

Another problem of the work is that the solar panel may not be able to generate enough power for a full charge of the battery.