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IIRC, there are some nasty heavy metals in some perovskites. Does anybody know which type is used in these projects? I'm 3000% in favor of solar, but still it bothers me if they use Pb etc...





I focused on PV in college and the fact is solar is dirty and they haven't planned for end of life recycling. The potential is great and we will get there im sure, but I always thought it was irresponsible to subsidize and widely roll out especially the early stuff in the 90s that was very inefficient and filled with heavy metals and REE. I'm not up to date now but the only thing I can say is at least the efficiency is better even if they are using similarly toxic elements.

I'm probably much less well-informed than you, but I can't understand the arguments about the disposal of the panels at the end of their life. I throw away a wheelie-bin worth of trash every single week, that's 1040 wheelie bins over a 20-year panel lifetime, yet those panels are probably equivalent to about two wheelie bins. It's a microscopic volume. What is in solar panels that is such a disaster compared to household trash? In 20 years I also expect to go through ten phones and five computers (although admittedly I'd chuck them into the local electronics recycling bin).

Heavy metals in thin film, mostly. Cadmium isn't great. They can be highly recycled though. Nevertheless, if a storm destroys a bunch of panels lots of cadmium will be dispersed

Cadmium telluride is not the prefered technology for solar cells. Silicon is still the major player, and it is free of any pollutants. I checked the wikipedia page for "solar cell". Given these informations, any consumer or technologist can adopt solar without compromising on pollutants.

The amount of oil or natural gas for the equivalent amount of energy that will be saved is worth it.

Old panels were bad, but without it we wouldn't have today's cheap and efficient panels, with more drops to come.

Just like with batteries, recycling will become more profitable and thus researched as we march forward


Batteries being made today will last 30 years, the first 15 will most likely be in a car and after that in a house battery. In 30 years we'll have drastically different ways of coping with waste so this concern about recycling is such a red herring.

If "recycling details" can be figured out later, then the same argument can be used to justify a massive investment in nuclear power, ie. 4th generation reactor, LFTR, you name it. It would generate more energy over its lifetime than PV ever would.

One key difference between solar and nuclear is that when solar goes wrong it goes wrong in a pretty small way.

Nuclear’s failure states are pretty awful, see Chernobyl, Fukushima for disasters, but just (something I learned as a kid) the Irish Sea being quite significantly radioactively polluted through normal operation of plants in the area.


The cost to dismantle millions, if not billions of tons of PV cell in 30 years is gonna be pretty higher, both in term of cost AND ecological impact than a localized power plant.

Also, Chernobyl is not a Gen4 reactor, the core design of RBMK reactor was highly unstable, and that the problem with anti-nuclear lobbying: we're stuck with old design we have since learned a lot from.


>The cost to dismantle millions, if not billions of tons of PV cell in 30 years is gonna be pretty higher, both in term of cost AND ecological impact than a localized power plant.

Got any figures for that? Higher than the ecological cost of dumping radioactive stuff into the pacific, or polluting the Irish sea?

As someone who might last another 40 years, but is hoping his kids last another 60 to 80, I'm OK if the cost is monetary in 30 years, as opposed to ecologically over that time.

> Also, Chernobyl is not a Gen4 reactor

Was Fukushima though?


> Got any figures for that?

Assuming a 15W per sqft, and an average weight of 3lb per sqft, and assuming the output of a nuclear power plant is around 1GW, you'll need about 9e+4T of solar panel that you're gonna need to recycle over a lifespan of 40 years. Just the volume of this waste is 4.5e+3 truck load, and I'm not even getting started about recycling the silicon cells themselves (ie. very nasty chemicals), and all this is just about 1 equivalent plants. US wide, you'd probably need 200x this (to be significant), plus a 5x extra capacity to deal with fluctuation and non-peak production, that's another 3 order of magnitude. You also need to factor into account a redesign of the grid to accomodate with the mesh production, and the extra battery on each site.

Compare this to burying a few hundreds tons per year of low volume wastes for ~eternity in a cave in the middle of nowhere.

> Was Fukushima though?

No, Fukushima used BWR design from the 1060's, so geneneration 2.


> No, Fukushima used BWR design from the 1060's, so geneneration 2.

Wow, animal-powered nuclear fission? These Heian period horse-drawn neutron beams were pretty ahead of their time though.


I'm totally happy if Nuclear becomes the major source that gets us off fossil fuels. But I'm also realistic. The cost, timeline, and red tape holding it back isn't moving fast enough.

Nuclear has been around for 70 years and it is still extremely expensive to dissemble nuclear plants and dispose of their wastes. In fact, in the US we still don't have a permanent solution to nuclear waste storage. And a lot of the radioactive materials in them are vastly more dangerous than what you find in solar cells.

Sorry, I checked and you are probably wrong, in the sense that silicon based solar panels (the vast majority) is free of heavy metals. The one you are maybe thinking about is cadmium telluride, and it's far from being widely adopted, precisely because of toxicity concerns.

Do solar panels eventually stop producing any power?

I have some second hand panels that are around 10 years old, I'm sure they are less efficient and I have had to replace diodes etc - but it seems to me that if you have lots of space (as we do in Aus) you could just keep adding new panels without getting rid of old ones


Solar panels you buy today just go down in efficiency - if you are installing them on say a house, they will continue producing good power output for the lifetime of the house (bar physical damage). Typically they will come with a waranty that after 25 years, they produce at least 80% of their rated output.

(You will probably need to replace the inverter during that time, but the panels will be fine)


Would it be viable to create a business to take the old panels and basically just mount them out in the desert to provide nearly free power (assuming you just do morning loads)?

The progress of PV technology over 3 decades means it's probably cheaper to recycle them for raw material and build out new PV.

Is there nasty heavy metals in current silicon panels? Have you more details? I'm (badly) surprised, I thought that would be merely the lead solder, solved by using lead-free one... Last I checked, I was under the impression that current technology was clean.

Photovoltaic is a fucking photodiode in the size of doors and windows right?

Unbelievable people think piles of huge diode in backyards is “green” somehow. I’m all in nukes since I realized that.


Why is a big photodiode not green?



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