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I don't seem to see a whole lot of discussions pertaining to the recycling of renewables which looks to be a huge issue.

Turbine blades are near impossible to recycle.

Solar panels are equally bad.

My question is, where does all this stuff go? Doesn't this stuff cost too much in terms of using rare Earth elements? Aren't we going towards the very bleak future when e.g. instead of containing our power appetites, limiting or reversing the population growth and increasing nuclear power plant output we are instead rushing towards a ... non-sustainable future?

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Initially addressing the issue of recycling wind turbine blade.

Apparently Kaunas University of Technology in Lithuania and the University of Strathclyde in Glasgow and Norwegian offshore wind developer Aker Offshore Wind worked out how to recycle glass-reinforced polymer composites (GRP) used in wind turbine blades.

The process is a two step process.

First, thermoset composites are split into fiber and epoxy. Second, the epoxy is further broken up into base components similar to virgin materials using a chemcycling process. These materials can then be reused in new turbine blades.

It remains to be seen whether turbine blades will be recycled this, or another way.

One possibility I thought of, and this is just an idea, it may be possible to grind the blades into a powder, or something similar, and use them as components of road making materials.

Concerning solar panels, they are being recycled in some parts of the world, but in very small quantities. Not enough to prevent most replaced solar panels from being dumped into land fill sites. The solar panel recycling industry needs to expand. This may happens as older solar panel are replaced in the future when the industry can rely on a steady supply of a minimum number of solar panels each year to enable recycling facilities to continuously operate at a required scale of operation throughout the year.

Up to 95 per cent of a solar panel can be recycled, with the most valuable parts being the glass, aluminium frames, polymers, silicon, copper and silver paste. The silver paste and aluminium frames are particularly valuable to obtain through this process. About 80 per cent of crystalline silicon can also be recovered through a refined recycling process.

Apparently,

Solar recycling is far more advanced in Europe when compared to the U.S.

In Europe,

European regulators are leading they way, and have developed a set of standards for recycling solar panels, requiring manufacturers to take back their panels at the end of their lives at no charge to the owners, and send them to a recycling facility where the components are broken down, sorted, and re-sold to make new solar panels and other products.

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Doesn't this stuff cost too much in terms of using rare Earth elements?

If this means these rare chemical elements, then no, it doesn't cost too much.

Turbine blades contain no rare Earth elements. What does contain is the magnets in the generator. Those can and will be recycled, unlike turbine blades for which recycling is hard. Actually rare earth elements are not necessary because induction generators can be used if we ever run out of rare earth elements.

Similarly, solar doesn't use rare earth elements at all so that's a non-issue.

For solar panels, the limiting factor is silver. Very little silver is used, so if you recycle used panels, you don't get much useful silver at all. Yet silver reserves are not huge, so every panel is gradually eating away our silver reserves.

The main component of solar panels is silicon. You could recycle it, but you get some impurities that are deposed on the panels during manufacturing stage. So for this reason, it probably makes sense to get our new silicon from as pure as possible silicon dioxide deposits.

You often hear it said that silicon is very common so solar panels can be made out of dirt. Actually this is not economically feasible. If we have orders of magnitude more silicon available than what we need, only the very purest deposits have significance, because the purer the deposit is, the less it needs to be purified after mining, so the cheaper it is.

If we ever run out of very pure silicon dioxide deposits (unlikely), we could use less pure deposits, and also recycle old solar panels.

Another significant component of both solar and wind power are the copper wirings. Those can and will be recycled.

Also remember the scale of the problem. A 1.5 megawatt wind turbine weights 164 tonnes. During its lifetime, it generates 100 000 megawatt hours of electricity. So waste is 164 tonnes per 100 000 megawatt hours or 1.64 kg / MWh.

Electricity generation from coal generates 1000 kg / MWh of carbon dioxide.

The wind power waste that is 1.64 kg / MWh is solid, so easy to store and contain. The coal power waste is 1000 kg / MWh and gaseous, so hard to store and contain.

A 1 kW solar panel weights 60 kg, and it creates 26 MWh of electricity during its lifetime. That's 2.3 kg / MWh waste, far less than coal power even though it's somewhat more than wind power. (Actually with solar, you need inverters too which creates slightly more electronic waste -- a 1 kW inverter weighs 10 kg, less than the panels though.)

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  • A great answer, thanks! What's your take on nuclear power? How does it slot in? Apr 2, 2022 at 13:40
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    Nuclear power is a very good way to create constant electricity without weather causing production interruptions. Waste can and will be handled properly, for example by storing it in Onkalo in Finland. However, constructing new nuclear plants today is perhaps bit too expensive, so I believe renewables will have a more dominant role than nuclear.
    – juhist
    Apr 2, 2022 at 18:28

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