Solar energy is one of the largest technological breakthroughs of the last hundred years. You likely know that solar panels harvest energy from sunlight and convert it into electricity, but you may not understand how that process occurs and what components make it possible. Understanding the solar panel production process can be a big help when deciding on a solar system.
A Quick Guide to Solar Panel Production
Solar technology is always moving forward, making for more efficient and durable solar panels. Research and development of solar tech is a competitive and complicated field, but here are the basics of how all solar panels function.
How Do Solar Panels Work?
Solar radiation — the light from the sun — is a potent form of energy, even after traveling 93 million miles in 500 seconds to reach Earth. The U.S. Department of Energy estimates that the amount of sunlight that warms Earth over 90 minutes has enough energy to power the entire world for one whole year.
Photovoltaic cells inside the solar panels absorb sunlight in the same way a dark car interior does on a sunny day. A car interior grows scalding hot as particles at the atomic level become full of the sun’s energy.
Unlike your car’s interior, photovoltaic (PV) cells make good use of that energy. Layers inside the solar panel contain alternating positive and negative charges. This creates an electric field that is energized and activated when enough sunlight has been absorbed into the PV cell.
Energy from the sun pushes electrons out of the PV cell’s layers. These now-charged particles are ushered along a current. Metal in the grid lines along the solar panels allows electricity to flow out of the cells and into the wiring of a home or business.
What Are Solar Panels Made Of?
Solar panel production starts with the element silicon, a semiconductor found naturally in sand. Semiconductors are materials that conduct electricity better than insulators such as rubber and glass but not as well as metals. They’re useful in electronics because they can hold a current without overwhelming a system with too much electricity at once.
One of silicon’s properties is that it can hold a positive or negative charge, making it ideal for setting up electric fields inside photovoltaic cells. This discovery was made in the 1940s, and solar cells made of silicon have existed since 1954.
How Are Solar Panels Manufactured?
Of course, the manufacturing process for modern solar panels is nothing like it was with the first panels. Here is a basic step-by-step overview of solar panel production:
- Raw silicon is melted at 2,000 degrees Celsius and goes through a refining process.
- The resulting high-grade silicon is formed into ingots, which are then cut into thin plates.
- The plates get a coating of silicon nitride. This surface coating is roughened to make the plates less reflective. This way, the plates hold onto more sunlight instead of bouncing it back like a mirror.
- The plates go through an inspection, with any cracked plates diverting to less-intensive uses. Testing with artificial sunlight ensures the approved plates will operate at maximum efficiency.
- A machine applies a layer of adhesive to a large pane of glass. This forms the ‘canvas’ for the solar panel.
- More machines align the silicon plates and a grid of thin metal atop the glass. An extra layer of adhesive seals all of the components together. Since the plates may crack during this process, the panels are checked again on a lit-up surface for small fractures.
- Once the panels are completely in place and double-checked, lamination machines press the adhesive and components together in a heated vacuum-sealing process. This process, along with coatings, weatherproofs the solar panels.
- An aluminum frame is placed around the delicate panels, providing structure for easier transportation and greater overall durability.
- A junction box goes on the back of the panel. This piece collects and manages the electricity the panel produces.
After final testing, solar panel production is complete. The panel is ready to provide clean and reliable energy.
Where Are Solar Panels Manufactured?
Unbound Solar’s solar panels are built in America. It’s important to buy solar panels from a trusted source, as the silicon plates inside are delicate. They can be damaged at many points in the solar panel production process. Multiple rounds of accurate testing are vital to verify a solar panel’s efficiency.
How To Recognize a Quality Solar Panel
Not all solar panels are created equal, so pay special attention to the efficiency and cost per watt to choose the best solar panels. A good efficiency rating for a solar panel will fall somewhere in the range of 14% to 22%. You can find the cost per watt simply by dividing the price by the number of watts the solar panel provides.
Climate factors can slightly decrease the efficiency of your solar panels, as silicon is slightly worse at conducting electricity at higher temperatures. To find out how much this will affect your solar panels, look at the temperature coefficient. This number will tell you how much the efficiency will decrease for every degree of increased temperature past factory conditions.
Many solar panel manufacturers offer long warranties since modern solar panels are so durable. You’ll want to check not only the length of the warranty but also how long the manufacturer has been in business. Though solar technology is a booming field, not all companies survive, so opt for established manufacturers.
What Top-Grade Solar Panel Production Means for You
There has never been a better time to make the switch to solar power. The U.S. Department of Energy has invested over $125 million into funding solar research and development and promoting American manufacturing of solar panels.
Many steps of the solar panel production process — such as extensive testing, improved metal grid layouts and innovative weatherproofing — deliver high-quality solar panels that can more than meet the demands of modern life. Solar panels are a durable, cost-efficient and environmentally friendly energy solution. Contact us at Unbound Solar for a quote along with expert guidance in selecting and installing the best solar system for you.