1.Introduction To Solar Panels

Most solar panels produced today are made from Silicon, the second most abundant element on Earth and the primary ingredient in beach sand. The first step in making a solar panel is to create silicon ingots, giant blocks of high-purity (99.999999%) silicon.



To do this, we put hundreds of pounds of silicon chunks (i.e. rocks) into a giant crucible and add a little boron (called a ‘dopant’) to give the silicon positive polarity. Then, we cook it altogether at over 2,000 degrees Fahrenheit! To do this, we put hundreds of pounds of silicon chunks (i.e. rocks) into a giant crucible and add a little boron (called a ‘dopant’) to give the silicon positive polarity. Then, we cook it altogether at over 2,000 degrees Fahrenheit!







We let the large silicon ingot cool down before slicing it into thin wafers using wire saws. Each fresh-cut silicon wafer is less than 200 microns thick – similar to a heavy piece of paper. These wafers must be carefully handled, inspected and cleaned before further processing.



The next step is to reduce the reflectivity of the wafer from about 30% to 10% through a chemical surface texturing process that creates tiny pyramids on the wafer’s surface. Now, when a photon (sunlight) hits the wafer's surface, it is more likely to be reflected into the wafer rather than back into space.







It's time to turn our silicon wafer into something that converts sunlight into electricity. This is where the solar cell, the heart of a solar panel, is officially born. To do this, we first inject phosphorus into the silicon wafer at high temperatures. Then, we carefully clean the phosphorous off the rear surface and around the edges of the wafer.



Now we have a photovoltaic (photo = light, voltaic = energy; thus, “light into energy”) device! Next, we deposit metal contacts on the front and rear surfaces of the cell, allowing us to collect those electrons generated in the silicon. We also deposit a thin chemical layer on the cell's surface to reduce its reflectivity from about 10% to 1%.







To make a solar panel, we string together 48, 60, or 72 of our solar cells and lay them carefully within an encapsulant, which attaches high-transparency glass on the front surface and a highly durable, polymer-based backsheet on the backside. Then, we warm the whole stack (like a toasted solar sandwich to create a protective cocoon around the solar cells.



Next, for structural stability and long-term protection, we place rigid aluminum frames around the perimeter, bonded together with a waterproof adhesive. Finally, we add a junction box to the back of the solar panel: a connector to facilitate the flow of electricity. Now, the solar panel is ready for quality testing, packaging, and delivery.







Once your solar panel is installed on your rooftop, sit back, relax, and let the sun save you money. Write a book, make coffee, or watch a soccer match on TV: you choose what to do with your solar electricity.



Furthermore, solar panels don’t have any emissions and they don’t make noise: they just sit their and do their job. Finally, take pride in the contributions you have made to combat climate change and to ensure a sustainable future for all




1.1 The Global Solar Movement



It's Abundant.



Solar energy is everywhere. You may not be able to dig a coal mine or oil well in your back yard, but with Solar panels you can harness nature’s highest source of power.



The sun sends enough energy to Earth each hour to meet human energy demands for an entire year! It’s the world’s most abundant and accessible source of energy.




It's Affordable.



Any serious, long-term global energy source must be scalable. Fossil fuels are generally supply constrained: as demand goes up, so do prices. With solar panels, it’s the exact opposite: as demand goes up, prices tend to go down!



The solar industry’s learning curve has been unprecedented. For the last 30 years, each doubling in global solar panel production has led to a roughly 25% reduction in solar panel prices!





It's Sustainable.



How do we want to leave the Earth for our children?

Silicon solar panels generate electricity without noise or emissions, and are comprised almost entirely of recyclable materials (like silicon, silver, and aluminum). In addition, solar (photovoltaic) panels do not require water for operation, critically important for sustainable communities around the world.

2.       Manufacturing Process of Solar Panels

1)Solar Cells Test. As the manufacturing condition of solar cells is randomness, the cells performance has some difference, in order to group the solar cells which have the same or close performance, they need be classified according to their performance parameter. The cells test is to test their current and voltage, then classify them, to improve the use ratio of solar cells, then make quality conformance solar modules.
2) Front Welding. It is to weld bus bar on the frontside of solar cells (Positive Pole), busbar is tinning copper ribbon, the welding machine can weld solder ribbon on the main busbar by multipoint method. The hot source of welding is an infrared light ( it exploits the heat effect of infrared). The length of welding ribbon is about double length of cell side. The excessive solder ribbon connects with backside electrode of the next solar cell when welding on the backside.
3) Series connection on the backside. Backside welding is to series connect 60pcs solar cells to form a module series. The positioning of solar cells mainly rely on a mould plate, it has 60pcs grooves to put solar cells, the size of groove is relative with dimension of solar cells, the position of grooves have been set, different specification solar module need use different mould templates, The frontside pole (Negative) of solar cell would connect with the backside pole (positive) of the next solar cell, then connect 60pcs solar cells to form a solar module and outgoing line.
4) Laminated Laying. After completing back cascading and getting throng test, laying cells string, tempered glass, EVA, fiberglass and backboard according to certain layers, prepare to laminate. Tempered glass can be coated a layer of primer in advance to improve the bonding strength of glass and EVA. Need ensure the position of cells strings, glass and other materials when laying, to adjust the distance among solar cells, to create a good preparation for lamination. (From bottom to top, the layers of laying is tempered glass, EVA, solar cells, EVA, fiberglass, back sheet).

3.       Applications

• Dairy: Solar Panel can be used to generate power to which can be used in the dairy industry for the process of sterilization, pressurization, concentration, drying and boiler feed water.
• Tinned Food: Here, the solar panels can provide temperature which can prove useful for processes like sterilization, pasteurization, bleaching, and cooking.
• Textile: Textile industry depends on extensive use of solar panels for efficient use of solar energy. These are used for the process like bleaching, dyeing, drying, degreasing, pressing, etc.
• Paper: In this industry, use of heat is required for various processes and uses solar panels to provide heat for the process like drying, boiler feed water, bleaching, etc.
• Chemical: These industries use solar panels for generating heat which is used for the production of soaps, synthetic rubber, processing heat, preheating water, etc.
• Beverages: We can see major uses of solar panel in beverage industries for the processes such as washing sterilization and pasteurization.
• Timber and by-products: Solar panels are used in the timber industry in the processes of drying, thermodiffusion beams, pre-heating water and in the preparation of pulp.
• Plastics: Solar panels are used to generate heat which is used in the process such as preparation, distillation, separation, extension, drying, blending, etc.

4.       Summary