| Work Detail |
The solar modules have an energy conversion efficiency of 10.8% and “adequate” tensile and impact strength, according to their developers. The research group claims to have used natural fibre composites as an environmentally friendly alternative to conventional polyethylene terephthalate (PET) backsheets.
An international research team has developed a solar panel that uses a backsheet made from a natural polyester resin and zeolite as an alternative to conventional polyethylene terephthalate (PET) backsheets.
The proposed innovation, according to its creators, aims to reduce the environmental impact of PET sheets and improve the thermal and mechanical properties of the solar module. The natural fibre backsheet was manufactured using vacuum-assisted resin transfer moulding (VARTM), which, according to the scientists, ensures optimal thermal management and insulation.
In the article « Comprehensive study on zeolitepolyester composite coated sheet for eco-friendly solar panels for enhanced panel performance and reduced panel temperature » published in scientific reports , the research group explained that the use of a natural fiber coated with zeolite-polyester resin was key to improving performance and reducing heat build-up in the panels.
“The use of zeolite-polyester composites with natural fibres ensures excellent structural integrity, uniformity and reliability,” the scientists stressed. “Although the initial cost may be higher, the long-term benefits include lower maintenance costs and improved performance, especially under harsh conditions.”
The VARTM process uses vacuum to facilitate the flow of resin into a fiber layer contained in a mold covered by a vacuum bag. After impregnation, the composite part can be “cured” at room temperature, and sometimes optional post-curing is performed.
The researchers began the process by waxing the surface of the fabrication table, marking out the dimensions, placing coiled tubes and applying sealing tape. They then used the film to make a “smooth” finish for the backsheet and placed additional fiber mats on top of the film. Another layer of peelable film and green mesh was then placed on top, after which the vacuum tube was connected to the coiled tube using a T-connector.
In addition, a feeding port was placed in the center for the monolayer fibers and two other feeding ports were placed diagonally. They then placed a vacuum cover on the perimeter of the sealing tape. “The dimension of the backsheet was 20 x 20 cm, and the thickness of the sheet was kept between 1.5 and 3 mm,” the researchers stated. “For each layer of supplied fibers, 90 g of zeolite and 135 g of polyester were used.”
The group built a 4.5W polycrystalline solar panel using Ecolam Max 3, an automatic solar module laminator with loading and unloading tape.
The 20cm x 20cm panel uses an aluminum frame and cells arranged in two columns, each of which is connected to the bypass diode to form an independent string of cells.
According to the research team, the coated version showed an 8% increase in voltage and 6% increase in current flow compared to conventional panels, while the pure sisal panels exhibited 4% more voltage and 3% more current.
“Coated pure sisal panels showed a 12% increase in energy output, while uncoated pure sisal panels demonstrated a 7% increase compared to conventional panels,” it further explained. “The efficiency of the solar panels improved from 9.75% to 10.8% with coated pure sisal and to 10.2% with pure sisal fiber backsheets.”
The academics also found that the production of sisal fibres emitted 60% less CO2 and required 50% less energy than PET backsheets. “Solar panels with sisal fibre backsheets exhibit adequate tensile and impact strength and reduce the operating temperature by 2-3°C, ensuring stable operation and minimising heat loss,” they added.
Looking ahead, the group says sisal fiber backsheets can be “effectively” used in solar panel manufacturing to improve performance and sustainability. “The application of natural fiber-reinforced zeolite-polyester composites in solar panels not only addresses environmental concerns, but also offers a pathway to developing high-performance, durable and sustainable solar energy solutions,” it concluded. |
