As the solar industry continues to expand at an unprecedented rate, the problem of what to do with discarded solar panels becomes more pressing. With a lifespan of about 30 years, millions of tons of solar panels are reaching their end of life and need to be disposed of or recycled properly. This is a significant issue as many of the solar panel materials contain toxic substances that can cause severe environmental and health problems if not handled correctly.

Environmental Impact of Discarded Solar Panels

According to Nature Energy, by 2050, the number of discarded solar panels will reach 80 million tons, causing significant occupation of space in disposal sites. The environmental impact of discarded solar panels is a serious concern. Cadmium, lead, and tellurium are among the toxic substances that can be released into the soil, water, and air if solar panels are not disposed of properly. These substances can cause significant damage to human health, including respiratory, digestive, and nervous system damage, as well as carcinogenic effects. Furthermore, accumulated discarded solar panels can take up significant space in landfills and recycling centers, exacerbating pollution problems.

Current Disposal Methods for Solar Panels and Their Shortcomings

According to the The National Renewable Energy Laboratory (NREL) the cost of recycling a silicon PV module in the US is about 15-45$, compared to the 1-5$ cost of dumping it in landfills. Currently, the most common method for disposing of solar panels is through mechanical disassembly. This process involves crushing, shredding, and milling the panels to separate the glass, aluminum, and copper from the silicon solar cells. While this method allows for some recovery of valuable materials, such as glass and metals, it often results in the incineration of the silicon solar cells. This is far from an ideal solution, as it means that many of the valuable materials in the cells are lost, and the incineration process can release toxic substances into the air. It is estimated that for a very common standard photovoltaic module of 21 kg, it is possible to obtain: 15 kg of glass; 2.8 kg of plastic material; 2 kg of aluminum; 1 kg of silicon powder; and 0.14 kg of copper.

Innovative Recycling Technologies for Solar Panels

To address this problem, there has been a significant amount of innovation in the field of solar panel recycling in recent years. New processes have been developed that allow for much more efficient and effective recovery of valuable materials, such as silicon, silver, and copper, from discarded solar panels. For example, some companies are using chemical processes to extract silicon from solar cells, while others are developing new ways to recover silver and copper. These innovations not only help to reduce the amount of waste produced by the solar industry but also create new opportunities for the recovery and reuse of valuable materials. The importance of recycling has been underlined by some estimation from the International Renewable Energy Agency (IRENA), according to which by 2050, the recoverable value in CRM could cumulatively exceed 15 B$, equivalent to the amount of raw materials needed in 2016, to produce approximately 2 billion new panels.

Upcycling Used Solar Panels

In addition to recycling, upcycling or repurposing used solar panels is also a viable option that can help reduce waste and extend the life of these valuable resources. Before considering disposal or recycling, it is essential to check the condition of solar panels and evaluate whether they can be refurbished or used for alternative purposes. For example, used solar panels can be repurposed for use in small-scale projects such as charging stations, portable lighting, or powering small appliances. By promoting the reuse of solar panels, we can reduce waste and create a more sustainable energy system that benefits both people and the planet.

Robotics for Solar Panels Recycling

Robotic technology has increasingly been used in the recycling industry to improve efficiency and reduce costs. Specifically, in the recycling process of solar panels, robotics can help automate the dismantling process and the separation of the different materials used in the panels, such as glass, silicon, and metals, which are then sent to be processed further. This automation can help reduce the amount of manual labor required for this process, making it safer and more cost-effective. Robots can also be used to move panels in support of human or automated controls, to evaluate whether the device is reusable or has actually reached its end of life.

Conclusion

While the rapid growth of the solar industry has brought many benefits, it has also created a significant challenge in terms of the safe and effective disposal of discarded solar panels. However, by continuing to invest in innovative recycling technologies and practices, we can ensure that we maximize the environmental and economic benefits of solar energy while minimizing its negative impact on the planet. By doing so, we can help create a more sustainable future for all.