Are Solar Panels Recyclable?

Solar panels
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Solar panels are mostly made from materials that can be recycled or reused. Components like glass and certain metals make up 80% of the mass of the solar panel and are relatively easy to recover. Polymers and electronic components from solar panels may also be recycled.

The reality of recycling solar panels is more complicated than simply taking them apart and reusing the components. The current recycling processes are not very efficient, and recovering the materials often costs more than producing a new panel.

However, there are significant incentives to optimize solar panel recycling: reducing costs, lowering the environmental impact of manufacturing emissions, and keeping toxic e-waste out of landfills. Given the rapid expansion of solar technology, solar panel recycling is an increasingly important part of the solar energy market.

Why Solar Panel Recycling Is Important

Solar panels reach the end of their useful life after about 30 years. As the use of solar panels grows, so does the amount of waste from broken or decommissioned panels. A significant increase in solar panel waste is coming. In fact, by 2050, waste from solar panels could account for 10% of the total electronic waste in the world.

Today, about 90% of solar panels end up in landfills, where, like all e-waste, they eventually leach toxic chemicals into the ground and water supply. (Thin-film solar panels, in particular, contain relatively large amounts of the toxic metals cadmium, tellurium, and indium. One study showed that cadmium telluride solar panels leached as much as 62% of their cadmium into the water after only one year.)

In addition to being better for the environment, recycling solar panels has an economic benefit. Over the next 30 years, recycled solar panel parts could have an estimated 15 billion dollar value and may be able to produce as much as 630 GW of electricity if used in new modules.

Solar Panel Recycling by the Numbers

  • Global solar electricity generation grew by 16% in 2020
  • Almost 78 million tons of solar panel waste will be generated by the top five countries by the year 2050
  • 96% of materials from silicon-based solar panels can be recycled
  • 97% of materials from non-silicon based solar panels can be recycled
  • Recycling one solar panel can cost between $15-$45 dollars
  • Disposal in a non-hazardous waste landfill costs around $1
  • Disposal in a hazardous waste landfill costs around $5
  • By 2030, materials recovered from solar panels could be worth up to 450 million dollars
  • By 2050, the value of recovered materials could exceed 15 billion dollars 

How Solar Panel Recycling Works

Glass, plastic, and metal—the main components of a solar panel—can all be recycled independently. But in a working solar panel, all those materials are combined to form a single product. The recycling challenge lies in separating the component parts in order to recycle them efficiently, as well as addressing the silicon cells, which require a more specialized recycling process.

For all types of solar panels, the cable, junction box, and frame must first be removed from the panel. Panels made of silicon are often crushed or shredded, and the materials are then mechanically separated and sent to different recycling processes depending on the type of material. In some cases, panels undergo a similar process of mechanical separation of the components, but then have to go through a chemical separation process known as delamination to remove the polymer layer from the glass and semiconductor material.

Components like silver, copper, aluminum, insulated cable, silicon, and glass can all be mechanically or chemically separated and recycled. Recycling components of a cadmium telluride (CdTe) solar panel is more complicated than the process used for solar panels with cells made from silicon. It involves several steps of physical separation as well as chemical separation and metal precipitation.

Other recycling processes involve thermally burning the polymers in the panel, or even cutting the components apart. “Hot knife” technology separates the glass from the solar cells by slicing through the panel with a long steel blade that has been heated to 356-392 degrees F.

Innovations aimed at optimizing the recycling process and recovering the highest purity materials are ongoing. For example, Veolia, a French company, uses robots to separate parts of silicon-based solar panels for recycling and has the ability to process 1,800 tons of solar panel materials per year. It plans to expand that capacity to 4,000 tons in 2021.

The Current State of Solar Panel Recycling

In the U.S., when solar manufacturers take back used solar panels, they can either dispose of or recycle them. Unfortunately, because of the labor-intensive process of recycling panels and the economics of the process, most solar panels in the U.S. end up in landfills. (If a particular type of panel has a higher amount of rare earth or valuable metals, it is more likely to be recycled since the benefit of recovering the metals is higher than the cost.)

When solar panels are recycled, it is most often done at glass recycling plants. The specialized glass from the solar panels is blended in with regular glass to be used as insulation. However, there is a lot of focus within the solar industry on optimizing the recycling process, and countries are exploring the possibility of building new recycling plants specific to solar panels.

In 2012, the European Union issued the Waste Electronic and Electrical Equipment (WEEE) directive, which requires the recycling of e-waste like solar panels in order to protect human health and the environment. Because of this regulatory mandate, Europe became the only continent that has recycling centers dedicated to recycling solar panels.

Other countries, including Australia, India, Japan, and South Korea, are currently developing guidance and mandates for solar panel recycling. In the U.S., the question of solar recycling mandates is left to the states; currently, Washington is the only state with such a mandate.

Can Solar Panels Be Reused?

Used solar panels are an emerging market. When solar panels are returned to the manufacturer under warranty because of a defect, they are often refurbished and sold again if repairs are possible. They may need a new frame, junction box, or even new solar cells. They are then labeled to indicate that they are not new and therefore not as reliable and resold at as much as 70% less than brand new panels. These solar panels are marketed as “second generation” and are sold by various suppliers.    

How to Recycle Solar Panels

Solar panel recycling is in its early days. For consumers in the U.S., that means that recycling your solar panels at the end of their usable life will require a bit of time and research. Start by checking a global database of solar panel recycling companies, or check to see if your state maintains its own directory for solar recycling, like this one from North Carolina.

Some solar panel manufacturers, such as First Solar, offer their own take-back and recycling program. Customers can return solar panels at the end of the panels' life and the manufacturer will recycle them. Contact your manufacturer to find out if they offer this service.

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