DATE: August 22, 2020

SNIP: Solar panels are … complex pieces of technology that become big, bulky sheets of electronic waste at the end of their lives—and right now, most of the world doesn’t have a plan for dealing with that.

But we’ll need to develop one soon, because the solar e-waste glut is coming. By 2050, the International Renewable Energy Agency projects that up to 78 million metric tons of solar panels will have reached the end of their life, and that the world will be generating about 6 million metric tons of new solar e-waste annually. While the latter number is a small fraction of the total e-waste humanity produces each year, standard electronics recycling methods don’t cut it for solar panels. Recovering the most valuable materials from one, including silver and silicon, requires bespoke recycling solutions. And if we fail to develop those solutions along with policies that support their widespread adoption, we already know what will happen.

Solar panels are composed of photovoltaic (PV) cells that convert sunlight to electricity. When these panels enter landfills, valuable resources go to waste. And because solar panels contain toxic materials like lead that can leach out as they break down, landfilling also creates new environmental hazards.

Most solar manufacturers claim their panels will last for about 25 years, and the world didn’t start deploying solar widely until the early 2000s. As a result, a fairly small number of panels are being decommissioned today. PV Cycle, a nonprofit dedicated to solar panel take-back and recycling, collects several thousand tons of solar e-waste across the European Union each year, according to director Jan Clyncke. That figure includes solar panels that have reached the end of their life but also those that were decommissioned early because they were damaged during a storm, had some sort of manufacturing defect, or got replaced with a newer, more efficient model.

In the United States, [recycling] is the Wild West: With the exception of a state law in Washington, the US has no solar recycling mandates whatsoever. Voluntary, industry-led recycling efforts are limited in scope. “Right now, we’re pretty confident the number is around 10 percent of solar panels recycled,” said Sam Vanderhoof, the CEO of Recycle PV Solar, one of the only US companies dedicated to PV recycling. The rest, he says, go to landfills or are exported overseas for reuse in developing countries with weak environmental protections.

Even when recycling happens, there’s a lot of room for improvement. … Recyclers often take off the panel’s frame and its junction box to recover the aluminum and copper, then shred the rest of the module, including the glass, polymers, and silicon cells, which get coated in a silver electrode and soldered using tin and lead. (Because the vast majority of that mixture by weight is glass, the resultant product is considered an impure, crushed glass.) Tao and his colleagues estimate that a recycler taking apart a standard 60-cell silicon panel can get about $3 for the recovered aluminum, copper, and glass. Vanderhoof, meanwhile, says that the cost of recycling that panel in the US is between $12 and $25—after transportation costs, which “oftentimes equal the cost to recycle.” At the same time, in states that allow it, it typically costs less than a dollar to dump a solar panel in a solid-waste landfill.

“We need to face the fact that solar panels do fail over time, and there’s a lot of them out there,” he said. “And what do we do when they start to fail? It’s not right throwing that responsibility on the consumer, and that’s where we’re at right now.”