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> without wind as a kind of a complement, solar is completely not feasible

This is not correct, and there is no reason to even suspect it might be true.

> the one message where I got sloppy and referenced only solar panel[sic] with a passing reference to 'rare earth minerals'

It wasn't a passing reference; it accounted for the vast majority (99.9% to 99.99%) of the resource and environmental impact you attributed to "a typical solar panel":

> A typical solar panel weighs around 40 pounds. All that material has to be mined from somewhere, then transported, then processed. Some of that material are rare earth minerals that have an outsized mining requirement (like for every 1 pound, you need to turn over 1000 pounds or 10000 pounds of earth). All of that material will need to be landfilled at some point in the future as well, no matter how recyclable the solar and wind collectors are (and today, they aren't recyclable at all).

Your describing it as "a passing reference" reinforces the impression that you have no interest in what might or might not be true, only in finding excuses to attack people. The question of whether making a 40-pound solar panel requires 30 kg of rock or 20 000 kg of rock is absolutely central to your purported primary concern here: the environmental impact of mining and waste management. Yet you dismiss this as "a passing reference"? How is it of no consequence to you whatever if a problem you are concerned about is literally a thousand times less serious than you had thought?

The only correct thing in your paragraph quoted above is that a typical solar panel weighs around 40 pounds (18 kg in non-medieval units), and that materials cannot be incorporated into a panel without being mined, transported, and processed. (And some stuff about wind generators I'm not even going to address.) As you can easily verify, a square meter of 100-μm-thick silicon wafer only accounts for 230 grams of that; the other 98% of the weight is mostly glass, aluminum, silver, and copper, which are extremely recyclable and have been thoroughly recycled since their discovery — centuries at least, millennia in some cases.

It's true that nobody's recycling the silicon at present, but that's not because it's difficult — it's that there isn't enough scrap solar-grade silicon out there to recycle, because the vast majority of the panels ever made are still being used, not scrapped.

> You forgot that Solar[sic] and Wind[sic] need to be overprovisioned

I did no such thing. I referred to PV capacity factors explicitly in about half a dozen places in the comment you are responding to. Depending on how you count, about a third of the text in the comment to which you are responding, saying that it "forgot that solar...need[s] to be overprovisioned" is specifically about capacity factors; that is to say, it is specifically addressing the fact that solar needs to be overprovisioned, and calculating by roughly how much. I could not be further from forgetting that solar needs to be overprovisioned.

As for wind, my comment didn't mention wind at all.

My notes on batteries are in https://dercuano.github.io/notes/lithium-supplies.html.

> also enough to store to bridge the daily, seasonal and inter-annual intermittency

No, that is a bad idea. You may need to store energy to bridge daily intermittency, but for seasonal and interannual intermittency you need to overprovision. (Except in the Arctic and Antarctic, where you should probably just get fuel or electricity shipped to you.) Where do you think the seasonal and interannual intermittency problem is worst, and how bad is it? Then we can calculate by how much extra we need to overprovision to handle it, or how far we need to run transmission lines to avoid it. Please stop this vague gesturing at potential problems and provide specific, verifiable data and careful reasoning, as I have done.

> you're placing high-tech devices in that area. Devices that need maintenance. Devices that break-down. Devices that need to be decommissioned

Solar panels do not need maintenance, although they are more efficient if you dust them occasionally. Some of them do break down, but this is unusual, usually due to design or manufacturing defects or very extreme weather. They generally do not need to be decommissioned. Typically they have a design lifetime of 25 years but continue to produce slightly reduced amounts of power for decades after that. https://www.nrel.gov/state-local-tribal/blog/posts/stat-faqs... https://www.nrel.gov/pv/lifetime.html Silicon solar cells haven't existed for long enough for us to see how long they last naturally; the first ones manufactured 60 years ago are still working.

Inverters and charge controllers do break down and need to be replaced every ten years or so, but there are many fewer of those; the maintenance load is similar to that of any other kind of power plant serving the same load.

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