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Solar panel waste may not be as bad as we thought

fastcompany.com

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Re: Solar panel waste may not be as bad as we thought

#41

Post by Schroedingersat »

akira2501 wrote: post #37
nostromo wrote: post #33

Aren’t they mostly silicon and recyclable metals? If so, who cares about the waste? It depends on what’s in the waste that matters, not its raw volume. The materials used in solar panels are both highly recyclable and environmentally benign, a great combination.

It's the Gallium Arsenide, from my understanding. There are processes to recover the Gallium, but it produces a waste that's very high in Arsenic.

The only GaAs involved in solar is an optional amount in the power circuitry.

CdTe was briefly a thing for abiut 30% of the market, but peoplewill want the Telerium soon enough. Modern panels are sand and about 50g/kW net of silver. Recycling is mandatory.

Re: Solar panel waste may not be as bad as we thought

#42

Post by mschuster91 »

PaulHoule wrote: post #3

It’s a story similar to nuclear power, where people found it wasn’t that hard to extend the life of nuclear reactors a lot longer than originally planned.

> where people found it wasn’t that hard to extend the life of nuclear reactors a lot longer than originally planned.

France is showing right at this moment just how bad an idea that is. Over half their reactors are still down, most because of issues with cracks in pipes.

Re: Solar panel waste may not be as bad as we thought

#43

Post by Archelaos »

ThrowawayTestr wrote: post #16

It's mostly silicon, how bad could the waste be?

Solar modules contain lead for soldering and some contain cadmium telluride (CdTe).[1] If handled and recycled correctly, the risk of exposure of lead and cadmium into the environment is minimal. However, there is a possibility that such materials are released by accident (fire, cracks) or improper disposal. That is why there are demands that solar modules containing CdTe should be basically abandoned, as there exist alternatives. However, the overall risk appears to be comparable to that of other products containing these materials, such as many consumer electronics.

[1] CdTe has a low toxicity. However, it may pose a significant hazard if its cadmium is released by some chemical reaction, which cannot generally be ruled out.

Re: Solar panel waste may not be as bad as we thought

#44

Post by pjc50 »

akira2501 wrote: post #37
nostromo wrote: post #33

Aren’t they mostly silicon and recyclable metals? If so, who cares about the waste? It depends on what’s in the waste that matters, not its raw volume. The materials used in solar panels are both highly recyclable and environmentally benign, a great combination.

It's the Gallium Arsenide, from my understanding. There are processes to recover the Gallium, but it produces a waste that's very high in Arsenic.

Hmm.. there are a number of different chemistries, and they're not all clearly labelled like batteries. It appears the switch from phosphoros/boron dopants to gallium was quite recent: https://theconversation.com/the-sunlight-that-powers-solar-p...

But that's gallium dopant rather than GaAs.

There's also CIGS and CdTe "thin film" solar cells, which are extremely toxic in even small amounts. But those chemistries were never very popular.

As far as I can tell most cells currently installed are poly or monocrystalline silicon cells, which contain phosphoros/boron dopants and aluminium metallization for the contacts. Those are the cheapest and also least toxic formulation.

(Fun fact: you know what popular component uses GaAs? Red LEDs!)

Re: Solar panel waste may not be as bad as we thought

#45

Post by Schroedingersat »

thrown_22 wrote: post #22
ajuc wrote: post #14

Earlier quoted context omitted.

One of the reasons is that a lot of these downsides are overplayed, based on long-obsolete data or false altogether. For some examples: - electric cars are still burning fossil fuels cause powerplants burn fossil fuels (yeah, but electric cars go ~2 times further on 1 liter of fuel even if all our power came from fossil fuels which it doesn't) - rare earth minerals are limited which means we can't have everybody driv…

>- electric cars are still burning fossil fuels cause powerplants burn fossil fuels (yeah, but electric cars go ~2 times further on 1 liter of fuel even if all our power came from fossil fuels which it doesn't) No they don't. When you add the efficiency of the grid, the charging station, charging the battery and discharging the battery burning a lump of coal to power your Tesla has _no_ advantage over burning a bottl…

You forgot to include the other liter of fuel spent extracting, refining, and shipping the first one. Hence 2x. Also coal has double the emissions of oil per kWh so on an energy basis it's 1/4th

Re: Solar panel waste may not be as bad as we thought

#46

Post by delecti »

mschuster91 wrote: post #42
PaulHoule wrote: post #3

It’s a story similar to nuclear power, where people found it wasn’t that hard to extend the life of nuclear reactors a lot longer than originally planned.

> where people found it wasn’t that hard to extend the life of nuclear reactors a lot longer than originally planned. France is showing right at this moment just how bad an idea that is. Over half their reactors are still down, most because of issues with cracks in pipes.

That's less an inherent problem with extending the reactors' lifespans, and more a problem with all of the reactors being old. They built a bunch of reactors, and then stopped, so now they're all on the same maintenance schedule. If instead they had kept building over time, then they'd have a bunch of new ones, and advance warning to tackle problems those reactors might face eventually.

https://en.wikipedia.org/wiki/File:Histogramme_des_%C3%A2ges...

Re: Solar panel waste may not be as bad as we thought

#47

Post by Schroedingersat »

howmayiannoyyou wrote: post #19

Recycling solar panels is tough because glass fines are created, often inseparable from items that adhere to them. Those fines don't currently have secondary demand and they're a health and possibly environmental hazard. The CAPEX for recycling panels is high because size reduction and separation requires expensive (and expensive to maintain) equipment. I expect companies like American Battery Recycling, et. al., to…

Al, Si and trace amounts of silver have no health or environmental hazard, and the silver is the valuable bit. Please stop gas lighting based on obsolete technology that was only briefly popular in one country.

Re: Solar panel waste may not be as bad as we thought

#48

Post by ajuc »

ilyt wrote: post #28
ajuc wrote: post #14

Earlier quoted context omitted.

One of the reasons is that a lot of these downsides are overplayed, based on long-obsolete data or false altogether. For some examples: - electric cars are still burning fossil fuels cause powerplants burn fossil fuels (yeah, but electric cars go ~2 times further on 1 liter of fuel even if all our power came from fossil fuels which it doesn't) - rare earth minerals are limited which means we can't have everybody driv…

> - electric cars are still burning fossil fuels cause powerplants burn fossil fuels (yeah, but electric cars go ~2 times further on 1 liter of fuel even if all our power came from fossil fuels which it doesn't) So do hybrids. Burning fuel at power station isn't 2x as efficient as burning it in ICE engine; most of the savings come from not wasting power while braking

> Burning fuel at power station isn't 2x as efficient as burning it in ICE engine

ICE engines are under 30% efficient (not counting the losses to accelerating/breaking and standing on idle in traffic jams), multi-stage turbines at powerplants are 50-60% efficient (but the 60% ones are rare).

Re: Solar panel waste may not be as bad as we thought

#49

Post by haberman »

ilyt wrote: post #28
ajuc wrote: post #14

Earlier quoted context omitted.

One of the reasons is that a lot of these downsides are overplayed, based on long-obsolete data or false altogether. For some examples: - electric cars are still burning fossil fuels cause powerplants burn fossil fuels (yeah, but electric cars go ~2 times further on 1 liter of fuel even if all our power came from fossil fuels which it doesn't) - rare earth minerals are limited which means we can't have everybody driv…

> - electric cars are still burning fossil fuels cause powerplants burn fossil fuels (yeah, but electric cars go ~2 times further on 1 liter of fuel even if all our power came from fossil fuels which it doesn't) So do hybrids. Burning fuel at power station isn't 2x as efficient as burning it in ICE engine; most of the savings come from not wasting power while braking

> most of the savings come from not wasting power while braking

That doesn't check out for me. ICE engines are inefficient because much of the energy from the fuel is converted into heat rather than kinetic energy. Every ICE engine has a radiator whose sole purpose is to vent off waste heat from the engine. ICE engines don't even need a distinct heating element to keep the cabin warm, the waste heat from the engine is more heat than the cabin will ever need.

I don't know that much about how power stations work, but surely it is not this inefficient.

EDIT: Did a bit of reading on gas/coal power plants and it sounds like they are indeed very inefficient: as bad as 20 percent, as good as 60 percent: https://www.energy.gov/fecm/how-gas-turbine-power-plants-wor...

That is mildly horrifying.

Re: Solar panel waste may not be as bad as we thought

#50

Post by Schroedingersat »

Archelaos wrote: post #43
ThrowawayTestr wrote: post #16

It's mostly silicon, how bad could the waste be?

Solar modules contain lead for soldering and some contain cadmium telluride (CdTe).[1] If handled and recycled correctly, the risk of exposure of lead and cadmium into the environment is minimal. However, there is a possibility that such materials are released by accident (fire, cracks) or improper disposal. That is why there are demands that solar modules containing CdTe should be basically abandoned, as there exist…

They've been completely abandoned for a while now. If you stack the small portion of CdTe ones neatly somewhere, someone will want the Te soon enough.

Lead is already mostly phased out.

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