The new technology should improve the manufacture of solar cells and make them easier to recycle
Spotted: As climate change continues to affect the planet, we need renewable energy technologies – including solar panels – now more than ever. The primary component of a solar cell is pure silicon. When making solar panels, the silicon goes through several high-temperature processes known as annealing, where the cells are cooked in an oven. However, a team at Macquarie University has found that heating using microwave radiation is almost as efficient.
Using microwave technology has many benefits. First, microwave radiation can be focused, meaning the heat generated can be tuned to selectively heat just the silicon. It also provides almost instant results, thus saving time and energy. Because microwave annealing can be directed to specific parts of the solar panel, this makes it ideal for heating newer solar panels with more intricate internal structures.
The rest of the laminated panel of glass, plastic, and aluminium is unaffected in the microwave annealing process, which ultimately makes the cell easier to recycle. The plastic coating softens so much that it can be peeled off mechanically. This means the plate can be easily delaminated, and all the components can be reused after the end of a solar panel’s usable life without the need for harsh and toxic chemicals and extremely high temperatures.
Crucially, the microwave process also takes place at room temperature and in a clean environment, unlike traditional annealing in a high-temperature oven, where chemical substances are shed from the walls.
The research, led by Dr Binesh Puthen Veettil, was enabled by funding from the Australian Centre for Advanced Photovoltaics, and the work has been further supported by the Australian Renewable Energy Agency.
Written By: Anam Alam