The Solar Panel Trash Problem

There is an interesting post up on the Harvard Business Review site about the “dark” side of solar. This side consists of the increasing amount of waste generated by solar panels. As the economics and efficiency of solar panels become favorable for mass consumption, their numbers will increase. More solar panels installed means more future panel retirements. The latter will result in more solar panel trash.

A 2016 report by the International Renewable Energy Agency (IRENA) predicted that approximately 78 million tonnes of solar panel waste will be generated by the year 2050. How will we dispose of all that solar panel trash?

The Problem with Solar Panel Recycling

Most solar panel recycling plants remove silver and copper and burn contaminated steel and glass casings in cement ovens. But the process is costly and time-consuming. Based on current estimates, it costs around $30 to properly dispose of a solar panel through recycling. On the other hand, sending it to a landfill, where it is crushed along with other waste, costs anywhere between $1 to $2 depending on the landfill access fee.

Another problem is that of recovering expensive materials, such as silver, from solar panels in a cost-effective manner. A crystalline silicon solar panel is mostly composed of glass which can be crushed into different densities and sizes. The silver and aluminum encasings are more expensive to extract from the overall panel. But leaching of metals like lead that are contained in the casings is hazardous to human health and plants. Given the effort and time required, several solar companies send solar panels to, no prizes for guessing this one, third-world countries for disposal.     

Regulations Can Help   

Regulations can force proper disposal of solar panels. The Waste from Electrical and Electronic Equipment (WEEE) directive in the European Union ensures that solar panel manufacturers incorporate the cost of recycling into the sale price of panels. Since the directive also makes producers responsible for taking back panels after use, it forces them to incorporate recycling principles and components into the manufacturing process itself.

In Japan, project developers are responsible for disposing of solar panel and contributing to a decommissioning fund. Australia has formed a National Working Group to assess regulatory options for solar waste disposal. Victoria, the second most populous state in the country, already bans panels from landfills. India has a solar recycling plant, funded by the Netherlands, and is in the process of formulating regulations.

But China and the United States, the world’s biggest and second-biggest consumers of solar panels, are yet to sign onto a federally-mandated solar panel disposal regulation. Most solar panels in the United States are disposed in landfills. Sam Vanderhoof, CEO of Recycle PV Solar, estimated that only 10 percent of solar panels installed are recycled. (But it should also be remembered that, with an average life expectancy of between 21 to 25 years, not a lot of solar panels are retired in the United States).  With the exception of Washington State, no state has passed regulation concerning solar panel disposal. California, the biggest consumer of solar panels, considers them universal waste, making it easier to dispose of them as compared to hazardous waste. The Department of Environmental Conservation (DEC) in New York is also considering adding solar panels to their universal waste program.  

Can A Circular Economy Help?  

The recycling of solar panels at scale would be much easier if the solar panel industry had a standardized approach to the manufacture and design of solar panels. Multiple types of solar panels – crystalline silicone, cadmium telluride, copper gallium indium diselenide – are present in the market today. The cost to material recovery ratio for each of these panel types is also different.

For example, according to research by Bloomberg BNEF, the silver encasing present in solar panels has declined between 2016 and 2019. Therefore, it has become less cost-effective to recover silver from a panel in 2019 than it was in 2016. Panel design – cell width and size, wafer sizes – also differs between different solar panels. Establishing a circular economy is not possible unless there is scale and standardization in manufacturing practices. In January this year, solar panel manufacturers in China, which manufactures 80% of the world’s panels, called for standardization in the wafer size of panels.