How Are Solar Panels Made?

Although solar panels do the challenging job of generating solar energy from the sun, building a solar panel is pretty simple when built professionally in a well-run factory.

Here is a simple explanation of how solar panels are made:

• Thin silicon wafers become solar cells when they are treated with chemicals to produce an electrical charge when exposed to sunlight

• The cells are wired together in strings and sandwiched between layers of glass and EVA plastic

• The layers are heated to create a watertight seal

• The sealed layers are set inside a metal frame, and the wires are combined into a plastic junction box on the back of the panel, with two wires coming out of the junction box to carry electricity to other panels or a solar inverter

Now, let’s take a deeper look at the step-by-step process of how and where solar panels are made!

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Where are solar panels made?

You can find solar panel manufacturers in many places around the world, including the United States and Europe, but the vast majority of solar products (like polysilicon, silicon wafers, and photovoltaic cells) are produced in China, with panel assembly happening in China and many other southeast Asian countries.

Many companies have manufacturing in multiple locations. For example, Jinko Solar primarily manufactures its panels in China, Malaysia, and Vietnam, but also has a plant in Jacksonville, Florida. Similarly, Qcells solar panels are made by the Hanwha company in Korea, but Qcells also operates large manufacturing facilities in Dalton, Georgia. 

American-made solar panels are becoming more popular, as numerous companies have opened stateside facilities following the passage of the Inflation Reduction Act (IRA) in 2022. The IRA contains provisions that allow solar manufacturers to claim special tax incentives for building factories in the United States.

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What are solar panels made of?

At the most basic level, solar cells made of polysilicon or silicon, ethylene vinyl acetate (EVA plastic), metal, and glass are the key components of a solar panel. 

The most important component of a solar panel is the solar cells, which convert the sun’s energy into usable electricity. Solar cells are the photovoltaic (PV) component of solar panels, meaning they produce energy from the sun. 

Nearly all solar cells for residential panels are made with crystalline silicon, which is melted at high temperatures and cooled slowly. During this process, phosphorus or boron is added to the silicon to allow it to act as a semiconductor.

Most solar cells are made using monocrystalline silicon, which is formed into an ingot when a seed crystal is dipped into a molten bath of pure silicon and slowly rotated and lifted, allowing the crystal structure to grow. 

The silicon ingot is then sliced into thin sheets, and an anti-reflective coating is applied to capture the sunlight instead of reflecting it away from the panels. Thin lines are then cut into the cells to capture and move the electrical current within the cell.

Solar cells can be either p-type or n-type, referring to whether the base silicon wafer has a positive or negative charge. P-type silicon cells used to be the standard because they are easy to produce and more stable with ordinary manufacturing methods.  

More recently, better manufacturing methods have been developed to produce extremely high-quality n-type cells, which offer high conversion efficiency and lower susceptibility to light-induced degradation, or reduction in output when exposed to extreme sunlight.

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How are solar panels made?

Step 1: Build solar silicon cells that are either p-type or n-type, meaning positively or negatively charged. P-type silicon cells were the traditional structure of solar cells. A p-type silicon cell is built on a positively charged base, meaning the bottom layer is mixed with boron and the top layer is mixed with phosphorus.

But the n-type cell is built oppositely, with the phosphorus serving as the base. The main difference is that n-type cells offer more efficiency and they are not affected by light-induced degradation, or reduction in output when exposed to extreme sunlight.

Solar cells are made with crystalline silicon that is melted and mixed with gallium or boron to form wafers. Phosphorous is then added to the silicon, and along with the gallium or boron, these substances give silicon its electrical capability.

The silicon ingot is then cut into thin sheets, and an anti-reflective coating is applied to capture the sunlight instead of reflecting it away from the panels. Thin lines are then cut into the cells to capture and move the electrical current within the cell.

Solar cells become semiconductors of electricity, which is generated by the photovoltaic effect. When sunlight's photons are absorbed, electrons drift within the solar cells to create energy.

Monocrystalline solar panels are formed from one silicon fragment, but for polycrystalline panels, many silicon fragments are melted together in one large sheet to form the silicon wafers for the solar panel.

Step 2: Solder solar cells together to form one panel, usually 60 or 72 solar cells form one panel

Step 3: Install the backsheet which protects the bottom of the solar cells

Step 4: Install glass front. This allows light to filter through to the solar cells and provides a protective layer

Step 5: Seal a metal frame around the panel with silicon to fuse all of the layers together

Step 6: Install the junction box which protects the solar panel's electrical wires from damage

Step 7: Test solar panel for quality and strength before shipping it out for use.

After testing solar panels for quality, they are ready to be shipped out and installed on homes or for solar farm use. The manufacturing process for different types of solar panels is pretty similar, but there are a few types of solar panels, and each type has its own strengths.

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Testing the quality of newly manufactured solar panels

During the entire manufacturing process, the materials that are used to build the panels are monitored for any defects. For example, any cracked or bent solar cells are discarded.

Once solar panels are built, they go through rigorous testing to make sure that they can stand up to intense weather conditions, heat, and normal wear and tear. Additionally, it is important to test that the electrical current travels through the panels efficiently.

Finally, solar modules are tested for strength to make sure that they have a low likelihood of breaking due to hail or other falling debris. Testing the quality of solar panels is important to make sure they can generate electricity while being able to last their entire lifetime.

Should you make your own solar panels?

We do not recommend making your own solar panels, although it might seem easy to configure a panel with all of the proper materials. Errors in building your own panels, like starting a fire, outweigh the benefits of DIY solar panels.

It is best to rely on professionally built solar technology because they are built with rigorous standards and tested for durability. Finding the best solar panel company for your needs is is an important step to making sure your solar panels are made with high-quality materials that will provide solar power for their 25-year warranty, or more. Renewable energy from solar panels is one of the best electricity sources for reducing carbon dioxide from fossil fuels so adding them to your home is a great way to be part of the clean energy future.