If you want to know how solar energy works, the answer is dual in nature. It is as simple as getting warmed up in the sun and it is as complex as installing and using solar panels for generating electricity. Photovoltaic cells are the components in solar panels that transform the sun’s energy into electricity. Basically, moving photons are used in creating electric current inside the solar panels.
Photons get created inside the sun through the fusion of atoms. Any photon takes around one million years to reach the solar surface. Once it becomes free it takes just 8 minutes to reach earth. It is this energy originating in the form of a photon in the sun that is already powering lives on the planet including feeding plants, refreshing and redistributing water and creating other types of energy, including fossil fuel.
In the last few decades, there has been huge growth in the technology designed for harnessing solar power that doesn’t cause any pollution, radiation or noise. In addition, the new source of energy is not affected by the economical conditions that drive up the price of fossil fuels and hydro power every year.
Types of Solar Energy Conversion
Basically there are two approaches for conversion of solar energy into useful energy. These approaches are solar thermal and photovoltaic.
Solar thermal approach utilizes the energy from the sun to generate heat directly. In this case, solar panels are used for collecting heat from sunlight and transfer it for a wide range of heating applications including water and space. Usually, this type of solar panels are placed in such a way that they absorb maximum amount of heat from the sun for the maximum period during daytime.
This type of system also contains tubing that circulates water. Usually, this tubing is also called solar thermal collector. In this indirect technique some anti-freeze liquid is utilized in place of water. This liquid is warmed by the sun, which is then transferred to water collected inside a tank.
The photovoltaic approach uses the sun’s energy and converts it into electricity. Photovoltaic cells, also known as solar cells are usually made from silicon materials and they function by absorbing the sun’s light and not the heat from the sun. This is different from the thermal approach. A solar panel usually consists of several of these photovoltaic cells working together. And, several solar panels are linked together to generate higher amount of power.
Direct and Indirect Solar Energy
There is another set of approach followed when it comes to using solar energy. It can be used either directly or indirectly.
Direct Solar Energy
Electromagnetic radiation is the process used in this approach where useable energy is generated from sun’s energy. Some of the leading examples of using direct solar energy are as following:
- Generating instant electricity by using solar cells.
- Solar thermal collectors where the dark surface absorbs sunlight and warms water.
- Fibre optic cables fitted outside buildings for lighting purpose absorb sunlight.
- Solar sails used in spacecraft for moving it using direct sunlight.
Indirect Solar Energy
In the indirect method, several steps are involved in converting sun’s light into useful energy. The best examples of this approach are as following:
- Photosynthesis is one of the best examples of indirect use of solar energy. Plants transform the sun’s energy into chemical energy. And, this energy is converted into creating befoul, hydrogen and methane gas.
- Wind turbines and hydroelectric dams get their energy from wind and rain caused by sun’s energy.
- The ocean thermal energy is also indirect form of solar energy as it is caused because of the difference in temperature between the different ocean depths.