What’s the disposal plan for the cadmium in solar panels? Solar #16

Cadmium is a heavy metal that can make humans quite sick. Cadmium is a major ingredient in one particular type of solar panel called cadmium telluride. Dangers of putting that into a few hundred thousand panels, risks of leakage into ground water, and lack of disposal plans 30 or 40 years from now might, just maybe, possibly, be worth considering today.

A few minutes of research starts to outline the issues. My learning points are in bold italics, with article for each idea, and my comments on the article.

  • Cadmium is bad stuff.

4/21/11 – Energy Matters – Safety of Cadmium Based Solar Panels Questioned Again– Article points out cadmium dust is quite toxic. While encapsulated in a solar panel, it is safe, but if the panel is damaged, there is a significant risk of leaching into the ground or migrating to ground water or rain runoff. Since the panels are not considered hazardous by themselves, there are no restrictions on disposal, per the article. Oh, and silicon-based solar panels contain lead, which has the same issues, but not quite as dangerous as cadmium.

  • Cadmium is used in certain type of solar panel

Wikipedia – Cadmium telluride photovoltaics – Article gives lots of background that is way over my head. Suggests building cadmium telluride panels would reduce exposures to cadmium since it is encapsulated instead of sitting around waiting for disposal. Recycling in the manufacturing process is being addressed by the industry.  How the panels will be disposed in 20 or 40 years isn’t mentioned anywhere in the article.

  • The issues has been on the table for a long time.

9/24/08 – Gigaom – Cadmium: The Dark Side of Thin-Film? – This ancient article is one of the first that came up in an internet search – 2008 is a long time ago. Risks exist in using cadmium, even in cad-tel (hey, how cool am I to know that cad-tel is short for cadmium telluride? On the other hand, that was 6 years ago, so it might be an obsolete term and I’m already out of date. Oh well.).

Back in 2008 there wasn’t much visible in the marketplace addressing how to dispose of a few hundred thousand panels when they are taken out of service in 30 or 40 years. That’s the expected life of a cad-tel farm, according to the article.

  • How to dispose?  California regulators are trying to figure out what to do about solar panels…

9/28/12 – ReWire – When Green Becomes Garbage: State May Declare Used Solar Panels E-Waste – State regulators were considering categorizing solar panels as e-waste. That is a different category that hazardous waste.  This would make them subject to less regulation and apparently make it easier for recyclers to disassemble solar panels, salvage valuable contents, and safely dispose of non-reusable toxic components. Article is over my head, but helps.

  • …and realize the e-waste approach won’t work.

10/17/13 – ReWire – Trashing Old Solar Panels is a More Complicated Process Than You Think – The state agency decided against putting solar panels into the e-waste category. That would place far less requirement on disposing of the cadmium, lead, copper, and selenium left over after pulling out the reusable materials. Article provides helpful intro to the federal and state laws on disposing of dangerous stuff.

  • Whose going to pay for disposal in 20 or 40 years? Bankrupt companies won’t have any money to do so.

2/26/13 – Heritage – Bankrupt Abound Solar to Bury Unused Solar Panels in Cement – Solar panel manufacturer Abound Solar went bankrupt. They left behind 2,000 pallets of broken or unsold & unsellable solar panels (2,000 pallets, not panels). Had another 4,000 gallons of cadmium contaminated liquid in their shuttered facility.  State regulators ordered the panels to be encased in concrete and buried in a landfill. Oh, the EPA found the company didn’t have a hazardous waste permit, even though the article says they were generating 630 pounds of cadmium-laced waste a month while in operation.

This now-bankrupt company that left 2,000 pallets of unusable cadmium-laden solar panels illustrates my concern about disposal in 30 or 40 years. Lots of green companies are going under. As technology advances, lots more companies will do the same.

If a radical breakthrough in renewable energy technology makes those solar farms preposterously expensive instead of merely extremely expensive and if utilities then find some way to wiggle out of their 25 year contracts to buy overpriced electricity, there will be hoards of bankrupt solar farm owners each abandoning many square miles of solar panels.

Even if those solar farms stay alive for the full life expectancy of the panels, there’s still another question…. 

  • Whose going to pay for disposal? And where will the cash come from?

It will take a lot of cost and effort to safely dispose of all the cadmium and other toxic components of solar panels.

Those costs should be reflected in the accounting records (there’s a technical accounting rule that addresses that unless the companies and auditors are ignoring the rule). Setting aside sufficient cash to dispose of the panels ought to be addressed. The carbon footprint of disposing of those panels really should enter into the calculations of the environmental impact of solar energy.

It is probably more a reflection on my limited knowledge, but I’ve not read any discussion yet on what the plans are for disposing of hundreds of thousands of solar panels in about 2050 A.D.

Or who will pick up the tab.

Or how we can be sure the cash will be around to fund the cleanup.

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