Discarded solar panels are ending up in landfills, instead of being recycled, where toxic solar panel waste is leaking into the ground and water.
Solar photovoltaic panels, whose operating life is 20 to 30 years, lose productivity over time. The International Renewable Energy Agency estimated that there were about 250,000 metric tons of solar panel waste in the world at the end of 2016 and that the figure could reach 78 million metric tons by 2050. Solar panels contain lead, cadmium, and other toxic chemicals that cannot be removed without breaking apart the entire panel.
While disposal of solar panels has taken place in regular landfills, it is not recommended because the modules can break and toxic materials can leach into the soil, causing problems with drinking water. Solar panels can be recycled but the cost of recycling is generally more than the economic value of the material recovered. Used panels are also sold to developing world countries that want to purchase them inexpensively despite their reduced ability to produce energy. Regardless, solar panel waste disposal is a problem that needs to be addressed.
Washington State is the only U.S. state that requires the manufacturer to develop a recycle plan, but the state requirement does not address the cost of recycling. Adding a fee to the cost of solar panels would help ensure that the disposal issue is addressed in the event that the manufacturer goes bankrupt. Since 2016, at least seven solar panel manufacturers (Sungevity, Beamreach, Verengo Solar, SunEdison, Yingli Green Energy, Solar World, and Suniva) have gone bankrupt.
Because California’s solar panels end up in landfills at the end of their useful life, the state is in the process of implementing regulations to change that. California’s Department of Toxic Substances Control (DTSC) held a meeting with solar and waste industry representatives to discuss the disposal issue. The representatives and DTSC acknowledged that it would be difficult to determine whether a used solar panel should be classified as hazardous waste. The DTSC suggested building a database where solar panels and their toxicity could be tracked by their model numbers, but it is not clear whether DTSC will implement such a data base.
Natural events such as hail storms, tornadoes, hurricanes, earthquakes, etc. can cause damage to the panels. For example, in 2015, a tornado broke 200,000 solar modules at southern California’s solar farm Desert Sunlight. More recently, the second largest solar farm in Puerto Rico, generating 40 percent of the island’s electricity, was severely damaged during Hurricane Maria. With 100,000 pounds of cadmium contained in 1.8 million solar panels calculated for a proposed 6,350 acre proposed solar farm in Virginia, any breakage is a cause for concern. Further, even rainwater has been found to flush out cadmium within an intact solar panel.
Course of Action
The biggest problem with solar panel waste may be its large quantity. Because sunlight is dilute and diffuse, large collectors are required to capture and convert the sun’s rays into electricity. Those large surface areas require an order of magnitude more materials (glass, heavy metals, and rare earth elements) than other energy sources. Approximately 90 percent of most PV modules are made up of glass. However, this glass often cannot be recycled due to impurities such as plastics, lead, cadmium and antimony in the glass.