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That's why we should build renewables right? Then there's pretty much no waste.



Rare-earth extraction is pretty nasty

https://www.theguardian.com/environment/2012/aug/07/china-ra...

And e.g. neodymium extraction for wind turbine magnets produces waste with radioactive thorium https://inis.iaea.org/collection/NCLCollectionStore/_Public/...


Rare earth is also not a necessary component for wind turbines.

https://www.evwind.es/2017/05/31/rare-earths-and-wind-turbin...


But you need batteries to store energy for non-windy times, right? And those batteries will require rare earth materials.


For some chemistries, but there are multiple grid battery contenders which do not involve rare-earths. Even in chemistries that use it, Rare earth materials are being minimized or designed out.

https://rmi.org/rmi-reality-check-greener-friendlier-alterna...


No, you do not need batteries. Batteries are the most expensive form of energy storage, and societies usually choose the lower-cost of alternatives where presented them.

Furthermore, batteries do not require rare-earths. (A formerly-popular chemistry needed cobalt, which is not one.) Finally, "rare-earths" is just a name; the ones used industrially, including in some wind turbines, are not rare, and are anyway recycled.

So, no, no, and no.

We will need energy storage, eventually, after we have built out enough renewable generating capacity to charge it from. Fortunately, storage cost is falling very fast.


So what I'm reading is that "we don't have to do it this way, there are better options", but are the better options actually being used and getting traction? Right now batteries are what we're using to store spare energy as far as i know (could be wrong for sure here though).

I certainly might be using the term "rare earth" imprecisely, but cobalt is used in most batteries and mining it is in fact detrimental to the environment. It's just much more localized pollution than releasing methane or carbon, which is for sure a win in the climate change fight.

You say storage cost is falling very fast, but again, what are the technologies being used backing up that storage you mention? I'm pretty sure it's batteries, but I'm totally open to facts saying otherwise.


Existing storage is, by a very large margin, pumped hydro. Current hydro storage is mostly shared with hydro generation reservoirs, all of which encompass a watershed. New pumped hydro often uses just an elevated depression, dammed box canyon, or even a diked level spot -- no watershed needed -- and can bank sea water.

Storage as anhydrous ammonia or liquified hydrogen is attractive because tankage is cheap and transportable, and it can be burned in existing turbines or sold to other utilities or to industry as feedstock, fertilizer, or fuel. International shipping is has begun converting to ammonia fuel.

Storage as liquified nitrogen is similarly attractive. The production equipment is very mature tech. LN2 is boiled in ambient air to drive a turbine.

Underground compressed air is attractive because it is simple and cheap. Extraction is via turbines, optionally spiked with fuel.

Underground hydrogen is common because it is simple and slots into existing NG infrastructure.

Various underwater methods -- compressed air, evacuated-cavity, buoyancy -- are very cheap if the mechanical parts remain onshore.

Battery chemistries competing with lithium use cheaper, often heavier, sometimes less inflammable materials. Iron, molten metal, sodium-ion, "flow".

In all cases, the determiner of competitiveness is economics. It is far from clear which aspects will dominate, and which will end up cheapest in them. Batteries cost per max MWh stored. Some cost per max MW in or out, with cheap tankage. Some are very cheap to construct and add onto. Some produce saleable surplus. Round-trip efficiency is all over the map, and in some is improving fast. Round-trip efficiency doesn't matter like it did when top-line generation was costly.

One thing we know is that Energy Vault, a $2B market-cap property, will not be in the mix.


Now dig up all metals and other construction material used for the steam side and generators in fossil plants and make a comparison if that question is even worth to ask yourself.

Also consider that we will be able to recycle the materials used so the extraction should level off to only supplying potential market expansion and loss.


> Now dig up all metals and other construction material used for the steam side and generators in fossil plants and make a comparison if that question is even worth to ask yourself.

Is iron mining and refining as toxic as, say, lithium? Particularly when adjusted for how much extra mining you have to do for a particular amount of end product?

Just throwing out factors to consider like you are doing (and I just did) is not very useful unless you also include some numbers for scale. Do some research and share.


I believe these types of arguments should start with "What about..." sir. Also not sure how we got to fossil plants...


Coal and nuclear have equivalent steam sides. Well, nuclear often has even more complexity with separate loops with heat exchangers to minimize contact between the reactor water and rest of the plant.

CCGT turbines are a bit different in that they have turbine first, and then the same steam boiler to turbine setup.

That is why I ask. All generation from mechanical sources needs generators, they need control circuitry. Steam plants need boilers, cooling towers and what not.

Just wanted to point out that singularly focusing on "hurr durr renewables need to dig stuff out from the ground and not made using pixie-dust" is quite the irrelevant take since the entire energy generation industry shares so much complexity, no matter the source of energy.




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