Managing solar panel waste

Solar panels convert solar energy into electricity through solar cells (also known as photovoltaic cells). Solar panels sometimes contain toxic metals, which means they may designate as dangerous waste. Proper disposal is essential to protect the environment and human health.

Learn which laws, regulations, and exclusions could apply to solar panels generated by your business.

Not a business?

If you are an individual or household, find out how to recycle solar panels.

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When do solar panels become waste?

Solar panels become solid waste when they reach the end of their life. This means the solar panel will no longer be used for its intended purpose and you’ve decided to discard it (e.g., due to damage or it’s reached its life expectancy).

How do businesses manage solar panel waste?

Reuse

If you reuse a solar panel, or send it off-site for reuse, it isn’t a solid waste and therefore the dangerous waste requirements don’t apply.

Solar panels are generally built very robustly and can function for many years after their warranty expires. They produce less electricity over time, but most are guaranteed by the manufacturer to produce 80% of their original labeled rate after 25 years of use.

Recycle

There are two exclusions that allow businesses to recycle solar panels.

Household hazardous waste exclusion
Interim electronic waste exclusion

If the solar panel is on a residential home, it likely meets the household hazardous waste exclusion (WAC 173-303-071(3)(c)). If your solar panel waste meets this definition, you can:

Recycle it at a recycling center that accepts solar panels, or
Dispose of it at a standard Subtitle D Solid Waste Landfill, with approval from the landfill.

Note: If a utility leases solar panels to a residential location, then this is a business waste and isn’t eligible for the household hazardous waste exclusion. See the interim electronic waste exclusion for another management option.

If your solar panels do not qualify under the household hazardous waste exclusion, they may qualify for management using the Interim Enforcement Policy for Conditional Exclusion for Electronic Wastes.

Under this policy, businesses have the option to:

Assume solar panels are dangerous waste (rather than designating them), or if you know they already designate, then
Follow all guidance within the interim policy, then
Send them to a recycler that accepts solar panels, or a manufacturer takeback stewardship program that recycles solar panels (contact your solar manufacturer to see if this is an option).

Solar panels must be legitimately recycled. This includes reclamation and reuse of parts. Solar panels sent for recycling can only be accumulated for up to 180 days and must be moved off-site to a facility for recycling within 180 days.

Manage as dangerous waste

If you choose not to or are otherwise unable to recycle or reuse your solar panels, then you must designate your solar panel waste to determine if it’s dangerous waste. This can be demonstrated by:

Analytical test results that show whether the panel is dangerous.
Using your knowledge of the materials in the panel.

Solar panels sometimes designate as dangerous waste by exceeding the limits for lead or cadmium (see Toxicity Characteristics List (WAC 173-303-090)) or designate as toxic for state-only criteria (WAC 173-303-100). You can also test if a waste meets state-only toxic criteria by using the method 80-12, Biological Testing Methods for the Designation of Dangerous Waste.

If your solar panels designate as dangerous waste and don’t meet either exclusion included above, manage them as fully regulated dangerous waste under the Dangerous Waste Regulations (Chapter 173-303 WAC), including disposal in a permitted Subtitle C hazardous waste landfill.

Frequently asked questions

There are generally two different types of solar panels:

Silicon solar panels (mono- and polycrystalline).
Thin-film solar panels.

Silicon solar panels are the most common. They may contain small amounts of metals within the panel, such as lead or silver.

Thin-film solar panels contain thin layers of semiconductor material, such as cadmium telluride or copper indium gallium diselenide (CIGS), layered on a supporting material. Cadmium telluride thin-film solar panels are more likely to designate as dangerous waste because they contain cadmium in significant concentrations.

Federal and state laws impact end-of-life solar panels and these laws continue to evolve as the industry evolves. In Washington, legislation passed to implement a solar panel takeback program.

The United States Environmental Protection Agency (EPA) plans to propose new rules in 2025 to add solar panels to the universal waste regulations (40 CFR 273), with a proposed final rule at the end of 2026. Until new rules are codified and adopted in Washington, follow all current regulations or the Interim Enforcement Policy For Conditional Exclusion for Electronic Wastes.

Learn more:

Most solar panels are a mix of glass, plastic, and metal. Around 80% of the solar panel’s weight is aluminum and glass, which are easy items to recycle.

With care, any solar panel can be recycled and turned into new products. Silicon, plastics, glass, and metals are all recovered in solar panel recycling. Manufacturers can reuse them to make new solar panels and other items. Recycled silicon is used to make new silicon wafers.

Contact information

Jared Mathey
360-706-3414
jared.mathey@ecy.wa.gov