Fields of solar panels are sprouting across co-op country. The amount of photovoltaic (PV) generation that electric cooperatives own or purchase increased nine-fold in the past five years, hitting 868 MW in 2017. Half of all co-ops now offer solar power to their members.

That growth means more clean, renewable power on the grid. But it also comes with a longer-term challenge.

Solar panels have an average useful life of 25 to 30 years, meaning within 10 years or so, the earliest solar power adopters will be looking at how to dispose of their panels. Beyond that date, the number of end-of-life panels will measure in the tens of millions.

In 2017 alone, more than 35 million new solar panels were installed in the United States, according to Solar Power World Magazine. A study by the International Renewable Energy Agency estimates that if PV panels were simply thrown away, they could amount to 60 million tons of waste worldwide by 2050.

The good news is, PV panels are largely recyclable. The U.S. solar power industry already has five national recycling centers, according to the Solar Energy Industries Association (SEIA), and is continuing to expand its efforts to prepare for a future when those panels begin coming down.

“Many of the manufacturers have plans in place for recycling their technologies,” says Jeff Pratt, president of Green Power EMC, a cooperative based in Tucker, Georgia, that provides renewable energy to 38 Georgia electric co-ops.

More than 80 percent of the material in PV panels by weight is glass and aluminum, both of which can be recycled and used in new panels, according to the SEIA. Copper, another commonly recycled material, is also a prime panel ingredient. Lesser amounts of other metals, silicon, and sealants present more of a recycling hurdle, but they can be separated out.

Overall, analysts say, some 90 percent of the material in panels can be recycled.

In Europe, where recycling procedures are more established, PV modules are typically crushed or shredded, and glass and aluminum are separated. Thermal processing uses high heat to recover copper and other valuable metals.

Photovoltaic thin film presents slightly different challenges, but First Solar, which manufactures the majority of PV thin film, has been a leader in solar recycling. The company says it can recycle more than 90 percent of the semi-conductors in PV modules and just under 90 percent of the glass substrate.

First Solar is one of the companies in SEIA’s national recycling program. The other four companies handle crystalline silicon PV modules, and some also handle other equipment, such as inverters.

“Anyone can use these companies’ fee-based services. It is likely that one of these companies will be able to help arrange for shipment or drop-off of the PV modules to a recycling facility,” says Dan Whitten, SEIA vice president of public affairs. “Our partners will also be able to walk you through any requirements unique to the given state where the PV modules reside or may traverse.”

Recycling in the United States has not been profitable so far, in part because of the relatively small number of panels available. But an International Renewable Energy Agency study estimated that by 2050, the raw material from recycled panels would be worth $15 billion and could be used to create millions of new panels.

‘Starting to ask questions’

Government, at least at the state level, has begun to address the issue of solar panel disposal. In Europe, PV module recycling has been required since 2012 through the Waste Electrical and Electronic Equipment (WEEE) Directive. The United States has not developed a national policy regarding panel recycling or end-of-life management, although some panels may fall under hazardous waste regulations because of small amounts of toxic elements, such as the metal cadmium. In today’s environment, analysts say, it’s possible for panels to end up in landfills.

The relative youth of most U.S. solar panels means disposal hasn’t been a major issue. But Dorothy Kellogg, NRECA’s regulatory director for environmental policy, says it’s attracting increased attention.

“People are starting to ask questions, and we’re starting to talk about the issue,” she says, “whether it’s within NRECA or the industry more broadly.”

In 2017, Washington became the first state to mandate solar panel recycling. Manufacturers who sell PV panels there will have to provide the last owner of the unit with locations where they can deliver used solar modules for recycling at no cost. Manufacturers who do not provide recycling will not be able to sell PV modules in the state after Jan. 1, 2021.

The requirements were part of a larger state bill that includes incentives to expand solar energy. Rep. Norma Smith, one of the bill’s supporters, noted, “It would be shortsighted to introduce a bill that expands the number of solar units in our state and not have a strategy for safe recycling when they’re no longer functional.”

Other states, including California and New York, are considering programs to further regulate PV disposal. The industry is working with state regulators to develop policies and strategies to make it landfill free, SEIA’s Whitten says. It’s also working to educate commercial recyclers on solar technology and what’s required to recycle PV products.

End-of-life issues

With the industry’s rapid growth and the possibility of more state or even federal regulation down the road, Kellogg says cooperatives that have their own solar arrays or are operating in partnerships with solar developers need to make sure they know the limits of their liability for panel disposal should the developer or manufacturer go belly-up.

She notes that severe weather, such as hurricanes, tornados, or even hailstorms, can necessitate replacement of large numbers of panels unexpectedly.

“There is time to develop the infrastructure for their end of life,” she says. “But co-ops should be thinking about how to manage liability for disposal of damaged PV.”

On the surface, the question of how to handle end-of-life issues for PV modules might not seem to be of significant concern for electric co-ops. Some co-ops have built and operate their own solar generation, but the bulk of cooperative solar energy comes from partnerships with developers and power purchase agreements with utility-scale solar farms.

In these cases, the installation—including the PV modules—are owned by the developers, and the handling of damaged or end-of-life units is their responsibility. And when panels malfunction, says Pratt of Green Power EMC, “many times, this equipment is under warranty, and we return them to the manufacturer because they want to do a root-cause analysis of the issue.”

Green Power EMC was organized in 2001 to support Georgia’s co-ops as they expanded their renewable energy portfolios. The co-op’s charter includes renewables of all kinds, but Pratt says their involvement in solar projects has exploded most dramatically because of the steep price decline of PV modules—70 percent in the last decade.

Green Power’s experience mirrors the national growth of solar.

Jan Ahlen, NRECA director of energy solutions, says economics have been a primary driver of solar adoption, given recent cost declines. The other important factor is “consumer demand for clean energy,” he adds. “Co-ops have been very responsive to their members when it comes to providing them with clean energy options.”

Pratt believes those member concerns, along with the historic co-op commitment to community, means electric cooperatives need to be thinking about and helping to develop responsible disposal and recycling standards.

“It is important. We need to look at the sustainability of all our [solar] processes and procedures and equipment, just like we do any other part of our energy production business,” he says. “It’s going to take some time for this to shake out economically and practically, but we need to be engaging and asking the questions today.”