With the first wave of solar power systems up for retirement within the next 10 years, and the International Renewable Energy Agency predicting continued exponential growth through 2050, the need to figure out how to “de-manufacture” complex component parts is growing, as well.

“The industry standard lifespan [for a solar panel] is about 25 to 30 years,” Ensia reports. So beginning around 2020, and for each year thereafter, “more and more will be pulled from service—glass and metal photovoltaic modules that will soon start adding up to millions, then tens of millions of tonnes of material.”

“We’re going to have a waste management issue,” said Garvin Heath, senior scientist at the U.S. National Renewable Energy Laboratory.

And recycling will be no easy feat: “The longevity of these panels, the way they’re put together and how they make them make it inherently difficult to, to use a term, de-manufacture,” said Mark Robards, a director for ECS Refining, one of the largest U.S. electronics recyclers.

On one hand, notes Ensia, some of the materials that go into a solar panel are hazardous (like cadmium). On the other, “75% of the material that gets separated out is glass, which is easy to recycle into new products but also has a very low resale value.”

With a view to encouraging the market for recycling end-of-life solar modules before they begin to pile up, “the solar industry is creating programs to train commercial recycling companies to understand what’s in manufacturers’ products and how to break them down,” said Evelyn Butler of the U.S. Solar Energy Industries Association.

But dealing responsibly with the rising tide of defunct PV parts will also require government standards and regulation, Ensia notes, despite the current lack of federal legislative oversight in the U.S. At the state level, regulations to date have been spotty: while Washington State, “not one of the largest solar-dependent states”, took the initiative last year to pass legislation “requiring manufacturers to finance the recovery and recycling of panels sold in the state,” solar leader California is “still likely years away” from enforcing a complete chain of custody. Washington’s regulation won’t likely be fully implemented until 2021.

The European Union’s Waste Electrical and Electronic Equipment Directive, by contrast, “requires producers to finance end-of-life treatment of solar panels sold in Europe,” Ensia notes.