Solar Energy

What Is Solar Energy?

Solar energy is defined as the transformation of energy that is present in the sun and is one of the renewable energies. Once the sunlight passes through the earth’s atmosphere, most of it is in the form of visible light and infrared radiation. Plants use it to convert into sugar and starches and this process of conversion is known as photosynthesis. Solar cell panels are used to convert this energy into electricity.

Solar Energy Advantages And Disadvantages

Advantages of solar energy are:

  • Clean: It is considered to the cleanest form of energy as there is no emission of carbon dioxide like in case of fossil fuels which is one of the causes of global warming.
  • Renewable: There is an ample amount of energy available on earth as long as the sun exists.
  • Reliable: The energy can be stored in the batteries and so there is no question of unreliability.
  • Reduction in utility costs.
  • Free energy because it can be trapped easily.

Disadvantages of solar energy:

  • The production is low during winters and on cloudy days.
  • Installation and the initial cost of the materials are expensive.
  • Space consumption is more.

Types Of Solar Energy

Solar energy can be classified into two categories depending upon the mode of conversion and type of energy it is converted into. Passive solar energy and active solar energy belongs to the mode of conversion and solar thermal energy, photovoltaic solar power and concentrating solar power.

  • Passive solar energy: This refers to trapping sun’s energy without using any mechanical devices.
  • Active solar energy: This uses mechanical devices to collect, store and distribute the energy.
  • Solar thermal energy: This is the energy obtained by converting solar energy into heat.
  • Photovoltaic solar power: This is the energy obtained by converting solar energy into electricity.
  • Concentrating solar power: This is a type of solar thermal energy which is used to generate solar power electricity.

Solar Energy Project

Solar energy – the experiment on the efficiency of the solar heating working model is one of the easiest science experiment that you can prepare in your school fair science project. This working model is quick, simple and very informative.

The result may vary if the project is performed outdoor due to the wind and weather condition, so it is recommended to conduct the experiment indoors.

In this solar heater project, use reflectors to concentrating the solar energy in one small place to collect and store heat energy. In this experiment, you will see the efficiency of solar energy.

Solar Energy

Materials Required

  1. A wooden stand
  2. Thermometer
  3. A concave or converging mirror
  4. Tube to flow liquid.
  5. Black paper

Procedure

  1. Mount the wooden stand
  2. Roll pieces of black paper around the tube.
  3. Attach the tube in the concave mirror in a way where the sunlight concentrate in one direction.
  4. Full the tube with tap water
  5. After 30 minutes record the temperature of the tube.

Observations

To calculate the efficiency of the concave mirror solar heater, you can divide the temperature increase by the direct sunlight. Eventually, the temperature of the water increase after 30 minutes as the heat is transferred through the concave mirror and concentrated on the tube.

Uses Of Solar Energy

  • Water heating: Solar energy is used to replace electric heaters and gas as efficiency is more with 15-30%.
  • Heating of swimming pools: Solar blankets are used to keep the pool warm. The other way is by using a solar water heater to keep the water warm.
  • Cooking purposes: Solar cookers are used for cooking food. Solar energy is used to heat, cook and pasteurize the food. Solar cooker consists of an elevated heat sink such that when food is placed in it, it gets cooked well.

Practise This Question

Identify the planet which has an almost same duration of rotation about its own axis as that of the earth.