Unravelling the Power of the Sun: How Do Solar Panels Work?

We are at the stage where concerns about climate change and the shift towards Renewable energy are growing rapidly. And to do this Solar Energy stands as a shining star. But many confusions and questions about solar energy and especially about Rooftop Solar are prevalent. Have you too pondered how these amazing technologies operate? We'll embark on an intriguing journey into the world of solar panels and examine the science that underlies their operation in this blog.

Solar energy is a very reliable source of energy. This energy can be captured by either capturing the light energy or the heat energy in the sun rays. Solar panels is a technology that captures the light energy in sun rays and converts it into electrical energy. Solar panels, which is the heart of a rooftop solar system, are made up of groups of photo-voltaic (PV) cells. Most commonly solar cells are made of silicon, which is abundantly available on earth.

So how does a solar panel work?

For this it is important to understand the anatomy of a solar cell.

Solar cells are made up 5 basic parts

1. P type semiconductor

2. N type semiconductor

3. Upper conductive layer

4. Lower conductive layer

5. Protective layer

There are two slices of semiconducting material (usually silicon) that are doped with other materials to give them a positive and negative charge. Generally phosphorus is used to give a negative charge (N type) and boron to give a positive charge (P type). These have a layer of conductive material and finally a glass protective layer at the top.

Sunlight consists of small energy packets called photons. When the sunlight falls on the solar cell, it knocks electrons loose from their atoms and an electric field is set in motion. The electric field is gathered and converted into an electric current by the attached metal contacts at the top and bottom of the PV cells. A DC current is created in the circuit. However, alternating current (AC) energy is used in the majority of households and businesses. An inverter is used to convert DC to AC. The inverter transforms the DC current into AC electricity, making it usable for feeding into the electrical grid or powering home appliances. In some situations, the electricity produced by solar panels can be stored in batteries for use at a later time, such as at night or on cloudy days, when sunlight is not available.

The solar panel technology can be dated back to 1883 when the efficiency was only 1%.

The solar panels available in the market today have efficiencies in the range of 10 - 20% meaning that they are able to convert 10-20% of the sun’s energy falling on them into usable energy. With advancement in technology, the efficiencies are getting better as well as there have been numerous experiments to make solar panels look aesthetically better.

There are different types of solar panels depending on the type of solar cells that they are made up of.

The technology is, for sure, a bit difficult to understand for a common person, but the benefit of solar PV technology makes solar panels a worthy investment. Compared to other renewable energy technologies, solar PV is a more accessible and affordable alternative. It allows any one with shadow free space to generate his or her own electricity and that’s the beauty of this technology.