How Solar PET panels are made? and its uses
A form of plastic known as PET (also known as Polyethylene Terephthalate ethylene-vinyl acetate (EVA) is often used for bottled water, takeaway containers (for food), and domestic products (for cleaning supplies) due to its material stability, wear resistance, and non-toxic nature.
Researchers in China are proposing a new technique to recover this polyethylene glycol terephthalate (PET) and ethylene-vinyl acetate (EVA) inat the end of their lifecycle. The two materials represent around 15% of the total material in a wasted solar cell, with a share of 10% for EVA and 5% for PET, respectively.
Because of PET and EVA’s high transparency and superior scratch resistance, it is appropriate for use as a protective layer atop the solar cell in some applications. The solar cells that are employed might be either monocrystalline or polycrystalline in nature.
This enables excellent sunlight absorption while still keeping thelightweight and portable. (compared to glass laminated solar panels).
- Exceptional clarity
- Resistant to ultraviolet radiation
- Resistant to humidity
- Good scratch resistance is a plus.
- Surface with a consistent textured pattern
- The appearance that is appealing
A common application for this technology is in compact plug-and-play outdoor solar LED lights, folding solar chargers, solar backpacks, and other solar-powered devices. In most cases, it is employed in applications requiring low voltage and low power.
Solar PET panel making process
Scientists from China’s Sun Yat-Sen University and the Shanghai Jiao Tong University have proposed a vacuum-gasification-condensation technology to recover polyethylene glycol terephthalate (PET) and ethylene-vinyl acetate (EVA) in solar panels at the end of their lifecycle.
For the PET & EVA decomposition and gasification process, a vacuum tube furnace is used. The furnace consists of a vacuum ionization gauge, a vacuum mechanical pump, a diffusion pump, and a control panel. Copper, tin, silicon, and silicon dioxide, which are all brittle materials, are crushed into particles with a size of less than 5mm, and the particles of PET and EVA, which are ductile materials and cannot be destroyed by the crusher, were fragmented into larger particles, with a size of between 5 mm and 20mm.
The PET and EVA are completely decomposed when the furnace temperature reaches 490 degrees Celsius. At the stage of 297-386 degrees Celsius, the weight of mixed PET and EVA start decreasing slowly, which indicated that the long bond of PET and EVA breaks in this stage. At the stage of 386-490 degrees Celsius, the decomposition process is the fastest mass loss at 461 degrees Celsius.
When the temperature reaches 505 degrees Celsius, the furnace’s pressure returns to the initial level and the PET and EVA are decomposed and gasified completely.
Finally, PET laminated solar panels are created by laminating layers of this gasified PET, EVA, and a solar cell together in a rectangular shape. They are then laminated by a machine operating at a temperature of 135 degrees Celsius for approximately 22 minutes, which causes the enclosing materials to melt together and produce a watertight seal.