Science & Technology, Australia (Commonwealth Union) – Solar cells are a revolutionary technology that has the potential to change the way we generate and use energy. A solar cell is a device that converts sunlight into electrical energy. This technology has become increasingly popular in recent years due to its ability to produce clean energy and reduce reliance on fossil fuels.
The basic principle behind solar cells is the photovoltaic effect, which is the ability of certain materials to convert sunlight into electricity. The most common material used in solar cells is silicon, which is a semiconductor material that can conduct electricity. When sunlight hits the silicon, electrons are knocked loose from the atoms in the material, creating a flow of electricity.
The invention of microwave technology at Macquarie University is set to enhance the production of solar cells, also making them simpler for recycling.
As the fabrication of solar panels takes place, silicon passes through many high-temperature techniques referred to as annealing. The cells are presently cooked in an oven.
Research appearing in the US Journal of Applied Physics Letters recently, however, had researchers led by senior lecturer Dr. Binesh Puthen Veettil of the School of Engineering demonstrate that heating with the application of microwave radiation is almost as efficient. Additionally, saving a sizable time and energy, with other benefits.
As microwave radiation selectively heats silicon, it brings about nearly instantaneous effects with wider economic factors for energy. This is partly due to the remainder of the laminated panel of glass, plastic, and aluminum being primarily with no effect. This also brings about the property that brought about an unexpected recycling advantage for which the group is awaiting a patent.
In recent years there has been much focus across the world by researchers on enhancing the effectiveness of solar cells as cost and efficiency have been some of the main barriers to switching to solar, energy along with other environmentally friendly alternative energy options.
With the application of microwave treatment, the plastic coating that guards the silicon plate against moisture along with contamination softens to the extent that it may be removed mechanically. This gives indications that the plate can be simply delaminated and the components reapplied with no requirement for harsh chemicals.
“Until now it made economic sense to just dump the panels in the landfill,” said Dr Veettil. “In the rare instances when they are recycled, you crush the panels, heat them to about 1400°C, and wash them with chemicals to remove the plastic — a highly energy-demanding process. But now, as the solar panels which began to be installed in vast numbers about 20-30 years ago are reaching the end of their life and being decommissioned, governments are demanding they be recycled.”
Microwave annealing has many other benefits. These include the capability to draw attention to microwave radiation which means the heating it brings about is capable of being selective and highly tuned. Certain recent panels, for instance, utilize what is referred to as heterojunction technology, which has crystalline and amorphous silicon interleaved. The quicker, better-directed annealing is more beneficial for these cells according to researchers.
The specific focus further indicates that annealing can be directed to particular areas of the solar panel, making it most suitable for annealing solar panels having higher intricate internal structures fabricated for special applications.
Many more projects utilizing solar cells and sustainable energy are taking place at Macquarie University. A co-author of the annealing paper, Associate Professor Shujuan Huang, is leading a group exploring microwave annealing in perovskite solar cells. Perovskite solar cells have also shown remarkable progress in improving their efficiency and reducing costs, making them a promising alternative to traditional silicon-based solar cells. Perovskite materials are also being explored for use in other applications, such as light-emitting diodes (LEDs), photodetectors, and catalysis.
