Solar panel material: What are solar panels made of?
Solar panels are made of a variety of materials which can be classified by their performance characteristics. In this blog let us discuss with you the three of the most abundantly used materials in solar panel production which are polycrystalline silicon, monocrystalline silicon and thin film. We will also explore the advantages and disadvantages of each material and look at some ways to choose the best one for your project.
The science behind how solar panels work
There are different types of solar panels, and each one functions with a slightly varying efficiency level to the other. For this blog, we will be talking mostly about polycrystalline silicon solar panels. To delve deep into the science behind how solar panels work, we need to take a closer look at what silicon atoms are. This is important since silicon is the main solar panel material used in constructing solar panels.
Silicon is a semiconductor that has an atomic number of 14, which means that it has 14 protons in its nucleus and 14 electrons orbiting around it. A solar panel consists of multiple smaller units called “solar cells”. Solar cells contain two layers of silicon, one which is negatively charged (more electrons), the other which is positively charged (fewer electrons). The negatively charged side is dubbed n-type and the positively charged layer is dubbed p-type.
When light shines on silicon, the energy from the light (photons) knocks out electrons from the n-type layer. The free electrons create a flow of electricity through the circuit all the way to the edge of the solar cell, which contains a thin metal strip. This strip is linked to an external circuit, which is where the power generated from the solar cell is used to power electric appliances.
The electrons then flow back from the electric appliance to solar panel, back into the solar cell, and into the p-layer of the solar cell, thus completing the circuit. This means that no electrons are permanently lost from the solar panel in generating electricity, which is why they remain functional for several decades.
The amount of current depends on how much light is shining on the silicon, how dense the material is, and how much space there is between the silicon atoms. Solar panels use this electric current (flow of electrons) to power electronic devices like laptops and cellphones.
Monocrystalline silicon is a very good material for solar panels because it has high efficiency when converting sunlight into electricity. Monocrystalline silicon also has a long lifetime and can be easily repaired if it starts to fail. However, monocrystalline silicon has one major drawback: it is expensive. In order to make solar panels more affordable, other materials are sometimes used in place of monocrystalline silicon.
Types of Solar Panels
There are different types of solar panels available for sale in the market made of different solar panel material. The most common four kinds are
- Polycrystalline solar panels
- Monocrystalline solar panels
- Amorphous silicon solar panels which is a Thin-film solar panel
- Cadmium telluride solar panels this is also a Thin-film solar panel
What Are The Solar Panel Materials?
The three main solar panel materials are glass, aluminum and silicon. Glass is the most common surface material because it’s affordable and can withstand high temperatures, Most importantly, glass is clear and lets sunlight pass through to the silicon layers that are underneath it. Aluminum is durable, lightweight and serves as a great frame for a solar panel.
Underneath the glass on the surface are several solar cells connected together, which is what generates electricity. These are the main ingredient for the power generation.
Solar cells are mostly just made of silicon. As we have mentioned at the beginning of this blog, not all solar cells are made the same way using silicon. While polycrystalline and monocrystalline solar panels are made of pure silicon, thin-film (amorphous and cadmium) solar panels are made of different materials. These include Cadmium telluride, amorphous silicon, and copper indium gallium selenide.
The solar panel material used affects its cost, efficiency, and durability.
How to Choose the Right Solar Panel for Your Home
Choosing the right solar panel depends on a few factors, such as your location, energy production needs and budget. To help you choose the right solar panel for your home, here is a look at different types of solar panels and their materials.
The three main types of solar panels are crystalline silicon, polycrystalline silicon and thin-film. Thin-film solar panels are further divided into cadmium telluride solar panels and amorphous silicon solar panels.
Monocrystalline silicon is made from a large block of single cells that are polished to a smooth finish. Polycrystalline silicon is made from smaller blocks of cells that are not polished. Thin-film cadmium telluride is made from small, flat pieces of CdTe that are printed onto a sheet.
Choosing the right solar panel is mostly down to how much they cost. Monocrystalline is generally the most expensive solar panel material, costing about a dollar and 50 cents per Watt. Then follows Polycrystalline, which costs about a dollar per Watt. The other options are relatively cheaper while also less efficient.
If you’re looking to make your own solar panel, the first place to start is by knowing all the materials that are used in the making of a solar panel. Silicon is used for the solar cells that collect sunlight and turn it into electricity, which are arranged in layers underneath the surface.
Aside from silicon for the solar cells, the surface is often made of glass since it is transparent enough to let the majority of sunlight through, and hard enough to protect the delicate solar cells underneath.
The frame is made of aluminum most of the times, since it is light weight and durable enough to hold the solar panel components in place.