Solare Energy Through Relays

INTRODUCTION:
Solar energy, radiant light and heat from the sun, has been harnessed by humans since ancient times using a range of ever-evolving technologies. The Earth receives 174 petawatts (PW) of incoming solar radiation at the upper atmosphere. Approximately 30% is reflected back to space while the rest is absorbed by clouds, oceans and land masses. The total solar energy absorbed by Earth’s atmosphere, oceans and land masses is approximately 3,850,000 exajoules (EJ) per year. The amount of solar energy reaching the surface of the planet is so vast that in one year it is about twice as much as will ever be obtained from all of the Earth’s non-renewable resources of coal, oil, natural gas, and mined uranium combined. Solar energy’s uses are limited only by human ingenuity. A partial list of solar applications includes space heating and cooling through solar architecture, potable water via distillation and disinfection, day lighting, solar hot water, solar cooking, and high temperature process heat for industrial purposes. To harvest the solar energy, the most common way is to use solar panels which are oriented in a specific direction.

PURPOSE OF PROJECT:
Since the solar panel is oriented in a specific direction, it uses the maximum possible solar energy when the Sun is exactly in front of it (i.e. the sun rays are normal to the solar panel). As the Earth moves around the sun or about its own axis, the solar energy striking the panel decreases and, therefore, the production of electricity from the panel decreases.

In order to get the maximum benefit of solar energy, the solar panel must move relative to the Sun, as the Earth moves, without using any manpower. In this project, we have made the solar panel to move as the source of light moves to achieve the target of maximum electricity production with less labour.

MATERIALS USED:
Relays, Transistors, LDR, Motor, 12 volt supply
METHOD:
In this project, two LDRs control the motion of panel through motor. When the light falling on these LDRs is same the motor brings the panel in static condition by stopping its rotation. As the light source moves, it changes the intensities of light on both LDRs i.e. more intensity on the LDR which is near to the source of light. This results in the rotation of motor in order to move the panel so that the light falling on both LDRs becomes equal. The polarity of the motor is controlled by H-bridge which is made by means of relays. A third LDR, whose sensitivity is greater than the two LDRs, is also used in order to cut the main supply when the two LDRs are in dark.

CONCLUSION:
Since the solar energy is very much available and is also a safe source from environmental point of view, its use is increasing day by day. Still we are not making the most of solar energy but the benefits of solar energy can be increased to a large extent if use solar energy tracking systems like this in order to meet the recent demands of energy in the World. This system requires no labour to change the orientation of solar panel. So it is also attracting from economical point of view.

AKNOWLEDGMENT:
In the making of this project, a great support of our university, teachers and friends is also involved. We are very thankful to all our teachers and friends who helped us and gave their valuable time as well as guidance to us.