The increase in solar energy across the globe has also raised concerns over the waste this leads to, with solar panels hitting the end of their lifecycle. Solar panels, which operate for 20 to 30 years, are now being dumped at a rate of millions of tons. According to estimates, total weight of all panels that have reached their end of lifecycle will swell to between 60 to 78 million tons by 2050, which will account for more than 10% of all e-waste produced globally. Interestingly, silver is among the main components of solar panels. It might seem minor, but it contributes to about 15% to 50% of the value of recycling assets. The panels used usually contain about 20 grams of silver, with the levels of that metal becoming much higher in old plates (up to 300-500 parts per million), which is comparable to levels of primary ore deposits.
The Challenge of Silver Recovery
Historically, recovering silver from solar panels has been a daunting task. PV modules are complex composites: layers of glass, encapsulant polymers (typically ethylene-vinyl acetate, or EVA), silicon solar cells, and metal contacts are fused together, making disassembly difficult. Traditional recovery methods rely heavily on hydrometallurgical approaches – essentially, dissolving the silver using strong acids like nitric acid. While effective to a degree, these methods come with significant drawbacks: they consume large volumes of corrosive chemicals, generate hazardous waste including toxic nitrogen oxide emissions, and are costly to scale. The economics have been particularly challenging – recycling a solar panel currently costs around $10 to $15, compared with only a few dollars to send it to landfill.
Breakthroughs Across the Globe
But the landscape is changing rapidly. In 2026 alone, multiple research teams have announced remarkable breakthroughs that bring us tantalizingly close to recovering virtually all the silver from end-of-life solar panels.
Advanced Oxidation Process. The advanced oxidation process was developed by scientists from Zhejiang University, Xi'an Jiaotong University, and the Chinese Academy of Sciences. The novel peroxide monosulfate (PMS)-based technology makes it possible to recover 100% of precious silver from various types of crystalline silicon solar cells within 20 minutes. Another advantage of this technology is its low environmental impact, which is 5% of the energy consumption and 2% of the chemicals used in earlier studies. The combined leaching and electrodeposition method allows obtaining silver with a purity of more than 99% without the use of acids, cyanide, and volatile organic solvents.
Continuous Flotation. Meanwhile, researchers at the University of Newcastle in Australia have successfully scaled up a froth flotation process – a mineral-processing technique widely used in the mining industry – to recover silver from solar waste without acid. In the world's first continuous pilot-scale flotation trial, the team processed 22 kilograms of solar-cell material recovered from approximately 460 kilograms of end-of-life panels (equivalent to about 23 residential solar panels) and achieved nearly 100% silver recovery. Under steady-state conditions, the silver concentration was upgraded approximately 83-fold. Perhaps most importantly, the flotation-based process could be three to five times less expensive than conventional acid-leaching approaches.
Molten Chloride Direct Separation. A team at Wuhan University took a completely different approach, developing a method based on molten chloride salts. Using a low-cost, non-toxic NaCl-CaCl₂-CaCO₃ system, they achieved 99.0% recovery of both silver and silicon simultaneously – and completed the separation in just one minute. This method breaks free from traditional reliance on strong acids or bases, and each kilogram of recycled batteries yields a net benefit of $14.04 while reducing CO₂-equivalent emissions by 11.0 kg. The technology performs excellently across mainstream high-efficiency battery types, including Al-BSF, PERC, and TOPCon.
Other Emerging Technologies. Additional innovations are pushing the boundaries further. A one-step hydrothermal process using tetramethylammonium hydroxide (TMAH) achieved 99.9% silver recovery with a processing cost of just 7.18 CNY per cycle and energy consumption of only 0.69 kWh. Researchers have also explored pulse laser recovery, mechanochemical pathways achieving 98.39% extraction efficiency, and deep eutectic solvent systems with leaching efficiencies above 99%.
Why This Matters
These breakthroughs are not merely academic achievements – they have profound implications for both the solar industry and the global silver supply chain. Recovering silver from end-of-life panels changes the economics of solar recycling entirely. As Associate Professor Mahshid Firouzi from the University of Newcastle put it: "Silver is the highest-value material in a solar cell. Recovering it has the potential to make solar-panel recycling far more financially attractive".
For Australia alone, by 2050, more than one million tonnes of waste panels are expected, containing an estimated 300 to 500 tonnes of silver. "We're effectively burying silver in landfill when we have the ability to recover it and return it to the economy," Firouzi noted.
The Road Ahead
While these technologies have reached Technology Readiness Levels around 5 – meaning they have been validated in relevant environments but are not yet fully commercial – the trajectory is clear. The question is no longer whether silver can be recovered from solar panels, but whether it can be recovered at a scale and cost that makes recycling commercially viable. With multiple pathways now demonstrating near-100% recovery efficiency, lower costs, and dramatically reduced environmental impact, that future is rapidly approaching.
The silver lining to the solar waste problem, it turns out, is literal silver – and researchers are on the verge of capturing every last ounce of it.
