James Elston

James Elston

Published June 8, 2024

Solar panels are made by extracting silicon from quartzite for the silicon wafers needed in solar cells to harness energy from the sun.

This is just a simple overview though. Solar panels go through extensive manufacturing and testing processes before they reach your home or business.

Let’s take a more in-depth look at this process as well as the testing and quality control methods used to ensure the panels are both safe and efficient.

What Is the Solar Panel Manufacturing Process?

Let’s delve into the specifics of the solar panel manufacturing process to give you a better idea of how they convert solar energy to generate electricity.

1. Raw materials and silicon processing

Silicon is the primary material used in the solar panel production process. However, glass, metal and various polymers are also used.

To produce solar panels, silicon is extracted from quartzite, which is a form of quartz sandstone rock. The silicon is then processed in an arc furnace to create metallurgical-grade silicon. This material is then further refined to achieve high-purity polysilicon through the Siemens process.

This process involves a chemical reaction that produces trichlorosilane, which is then distilled and decomposed at high temperatures to end up with pure polysilicon​.

2. Wafer production

The next step in this process is the production of silicon wafers. Using the purified polysilicon, the Czochralski process is undertaken to melt and form the silicon into cylindrical ingots.

These ingots are then sliced into thin silicon wafers using diamond-coated wire saws. Any irregularities are removed before processing them further.

3. Solar cell fabrication

In the next stage, the silicon wafers go through a doping process, which introduces boron or phosphorus to create p-type or n-type solar cells. Forming a p-n junction is essential for solar panels to generate an electrical current.

An anti-reflective coating is then applied to the panel to enhance light absorption. Lastly, metal conductors are screen-printed onto the wafers to form the grid pattern necessary for electrical connectivity.

4. Solar panel assembly

The thin film solar panels can now be assembled:

  1. The solar cells are interconnected in a series configuration using tabbing wires.
  2. These cells are encased between a thin layer of glass and a polymer back sheet to protect them from environmental damage.
  3. The entire panel is framed with aluminium to provide structural support and ensure durability.
  4. The final step is to seal the panel to prevent moisture build-up.

How Are Solar Panels Tested and Quality Controlled?

Polycrystalline and monocrystalline solar panels need to undergo rigorous testing before they can be sold. Here are some key steps involved in the testing process:

  1. Visual inspection: This initial step involves checking the solar panels for any visible defects such as cracks, scratches or manufacturing flaws. The idea is to ensure the physical integrity of the panels.
  2. Electrical testing: Panels are subjected to various electrical tests to verify their functionality and safety. The IEC 62446 standard outlines the requirements for system documentation, commissioning tests and periodic verification of PV installations.
  3. Performance testing: Performance tests, such as the flash test, simulate sunlight conditions to measure the electrical output of the solar panels. This test helps confirm that the panels meet their specified solar power ratings and efficiency levels.
  4. Durability and environmental testing: Solar panels are exposed to various stress tests to assess their durability under different environmental conditions. These tests include high-temperature, humidity and mechanical load tests to ensure they can withstand harsh weather and mechanical stresses.
  5. Grounding and safety checks: Ensuring proper grounding is essential to prevent electrical shocks and fire hazards. Regular checks are conducted to verify that the grounding system is intact and effective.
  6. Documentation and compliance: Lastly, comprehensive documentation of test results is maintained to ensure traceability and compliance with industry standards. Providing customers with detailed reports on the system’s installation, performance, and safety checks is also a key part of the process.

These stringent testing procedures help ensure that solar panels installed in the UK are safe, reliable and capable of delivering the expected energy output.

What Are the Environmental and Ethical Considerations for Solar Panels?

In line with the sustainable nature of solar panels, there are certain environmental and ethical considerations that form part of the manufacturing process.

  • Silicon mining: The extraction of silicon involves mining quartzite, which can lead to habitat destruction and pollution if not managed sustainably.
  • Energy consumption: The manufacturing process, particularly the production of silicon wafers, requires substantial amounts of energy. While the overall carbon footprint of solar panels is lower than fossil fuels, the initial energy input remains a concern. Efforts to use renewable energy sources during manufacturing can reduce this impact.
  • Waste generation: The production of silicon wafers generates waste, including silicon dust and slurry. Efficient recycling and waste management practices are essential to minimise environmental impact.
  • Recycling: Solar panels have a lifespan of about 25-30 years. As they reach the end of their life, recycling becomes important to recover valuable materials and reduce landfill waste. The UK is developing a better recycling infrastructure to handle the anticipated increase in solar panel waste.
  • Supply chain transparency: Companies must ensure that their supply chains are free from exploitative labour practices, including child labour and forced labour. This requires rigorous auditing and certification processes.
  • Ethical sourcing: Some materials used in solar panels, such as certain metals for conductors, may come from regions with conflict minerals. Ensuring that these materials are sourced ethically, without funding conflicts or human rights abuses, is essential.


What manufacturing standards are used in the UK for solar panels?

Solar panels that are produced in the UK are measured against the following manufacturing standards:

  • IEC 61215
  • IEC 61730
  • IEC 62466
  • Microgeneration Certification Scheme
  • BS EN 61215 and BS EN 61730
  • ISO 14001

What are solar cells?

Also known as photovoltaic cells, solar cells convert sunlight directly into electricity through the photovoltaic effect. They are the fundamental building blocks of solar panels and are essential for harnessing solar energy.

How does a junction box work?

A junction box is a critical component in electrical systems, including solar panel installations. It serves several important functions, ensuring the safety, reliability, and efficiency of the electrical connections.

The junction box acts as a central hub where multiple electrical wires are joined. In relation to solar panels, the box typically contains the terminals where the positive and negative leads from the solar cells converge.

Final Thoughts

There’s a lot of thought, time and effort that goes into bringing you the technology that can help reduce your energy costs and carbon footprint.

Understanding how solar panels are made and tested can help you make a more informed decision when it comes to choosing products and brands that specialise in solar technology.

At Eco Happy, we’re here to guide you on your solar panel journey by making it easier to source and install a system that works for your home or business.

If you’re looking for expert guidance on solar panel options or the installation process, we can help, all while ensuring you choose from the best, most ethical brands on the market.

Contact us for a free quote today.

James Elston

James Elston

Boiler Expert

James Elston is the top boiler replacement and heating expert at Eco Happy. He has over 20 years of experience in the industry, focusing on Gas Safe boiler installations and offering home-heating and energy-saving solutions to homeowners across the UK. From sourcing the most energy-efficient combi boiler to providing specialist heating advice, James ensures that Eco Happy maintains the highest standards and best customer service.

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