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Comment by once_inc | Hacker News Reader

Honest question: doesn't the production of battery and photovoltaic cells require quite an investment of rare elements and significant carbon emission?

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> significant carbon emission

What is significant?

Photovoltaic panels take around 1/30 of the energy they provide to build (that number is constantly going down). So if you replace all of our energy production in one go, it will take about 1 year of pollution to create them.

What is obviously a crazy idea that will never happen in practice. On the real world, the panels are produced more slowly, and are replacing the most polluting energy sources first.

(Batteries, by their turn, do not need as much energy to create.)

I imagine OP means the mining and production of batteries at grid and transportation scale will require an enormous amount of energy expenditure and resources.

Most storage will not be batteries. Most energy expended building storage will be from renewables.

There can be a saturation a point where that becomes true, but I can’t see how that’s possible upfront.

Virtually all of the national and global manufacturing and logistics is fossil fuel driven.

I’m not saying it shouldn’t be done but unchecked and without care our industries will take shortcuts and warp good intentions (like ethanol).

Most storage will be built after there is renewable capacity to charge it from, therefore available to build it with.

I can see it if it’s purely domestic end-to-end.

But at least in the US, we have a bad habit of outsourcing our problems away: Out sight out of mind.

If there’s any significant portion of the build out that’s non-domestic, then I have reservations.

Nobody gets a price break on their power bills when they make panels or batteries, and nobody pays for it and fails to pass on the cost.

Every single kWh that goes into making any piece of kit, whether battery, wind turbine, solar panel, e-car, or what-have-you goes onto its price tag.

I don’t mean price breaks.

How does one account for manufacturing and mining that is offshored, to ensure that they don’t use fossil fuels (like coal) in their process?

It’s the manufacturing analogue of organic food certification.

If you have any pull, feel free to liberally use this as your own :)

By the time much storage is being built, renewable power will be the cheapest choice, by far. So, you are worried that somebody up the line will choose to use expensive fossil-generated power instead of cheap renewable power.

Just by preferring the cheaper product, you bias your choice toward being made with renewables. It is not a guarantee, but in aggregate it is good enough.

That's the thing. Highly optimized portable batteries need some expensive materials, but stationary ones do not.

There is no reason for them requiring enormous amounts of energy, unless your definition of enormous is a trainload.

It did, but it does not any longer. Lifecycle estimates vary from 5x worse than nuclear to 50x better for solar and 5x worse to 5x better for wind.

At 30c/W, even if the only activity required to make a solar panel were dumping anthracite on the ground as you mine it and setting fire to it you would still get more energy per kg of CO2 than gas.

The raw materials are sand, are copper and silver for current PV tech with trace amounts (milligrams per kw) or dopants. The amount of silver per panel is decreasing faster than the rate of panel production is increasing. Copper is mainly for wiring up and can be exchanged for aluminium if scarcity and thus cost is an issue, and inverters require substantial amounts of exotic materials (but less per capita than a phone or laptop).

A nuclear reactor requires more steel than PV requires silicon, and commensurable amounts of exotic materials.

Wind turbines require about the same amount of steel as nuclear but substantially more concrete.

They last 20 years though. The investment pays off over a long period.

not just a cost question but a resource availability/energetic cost of resource extraction question.

If it takes more and more fossil fuel use to extract the increasingly rare components of the renewables, then renewables may not be able to save us.

I don't know if it is true, but it is a legitimate question which is worth knowing the answer to...

There are no "increasingly rare components".

So, no, it is not any sort of legitimate question. It is, rather, concern trolling.

My guess is he's talking about Lithium and if so that's not concern trolling, Lithium mining is very expensive and if we want to go full renewable we'll need some major storage capacity. There's obviously ways around that, hydro storage being the most obvious, but it is something to think about.

The question was too vague to guess what it was about, if anything. It presupposes there is some resource used for renewables that is scarce and for which there is no viable substitute. Without identifying any, it is just trolling: there must be trouble somewhere, what can you come up with for me to carp about?

Lithium is about electric cars, not about renewable energy production.

To the popular imagination, it is easy to make a popular misconception linking renewable energy to rare earth minerals, because for good or for ill electric cars are a dominant facet of green technology. There is a not uncommon narrative that "electric cars are actually bad for the environment because they require scarce metals." News stories abound.

https://www.reuters.com/article/us-metals-autos-neodymium-an...

https://www.forbes.com/sites/kensilverstein/2022/02/06/the-f...

Rude pedantic ill-tempered dismissals of conversation as "carping" discredit a good cause more than a thousand fusion startups do. Perhaps if you want to win hearts and minds, engaging in both education and a little empathy would do wonders for your position. And to the betterment of the discourse hereabouts.

"Rare-earth" metals, are not, in fact, scarce. Insisting otherwise is misinformed at best, or disingenuous in your case, because you have already been told otherwise.

I am misinformed. But you are impolite.

A gram or so of silver per kW is the rarest component of PVs, and the total ammount of (recyclable) silver per year the PV industry uses is going down even as production increases. The copper is less than a commensurable amount of steam generation. Silicon refining energy is a hundredth or so of output and declining rapidly steel in a nuclear reactor outmasses the silicon and has a lower but rapidly closing energy requirement. Frames can be aluminium or even wood. The glass outmasses steel in a nuclear reactor, but not concrete, and has a lower carbon footprint than concrete and is reusable.

Wind uses copper and niobium, neither of which are essential to the concept. The copper is currently more than steam generation, but some can and is being swapped for abundant aluminium. Magnet free stators are being worked on extensively and are close to cost competitive. Steel use of the largest turbines is competitive with nuclear so iron alloying materials are a wash.

Nuclear uses zirconium, uranium, cadmium, silver, and a variety of other exotic elements as well as the copper for the steam turbines. It is difficult to find out how much, but back of the envelope (0.1% of the fuel assembly being control rod so 0.2g/GJ) would indicate it's more constrained by silver and cadmium than PV is by silver. Plus it is high level waste at end of life and you need it all up front.

The only question is whether the concrete in wind is worth the CO2 as this is the only resource where nuclear wins.

No and no. Solar panels use a little bit of silver and more copper, and no rarer materials.

There are numerous battery chemistries. None competing for utility-scale use involve any rare materials or substantial carbon emission. Likely chemistries include iron/air, zinc/bromine, and manganese/calcium.

And the overwhelming majority of utility storage built will not be "batteries" at all. Compressed air, liquified air, synthetic ammonia, electrolysed hydrogen, pumped hydro, and buoyancy will probably all be used in various places. Just now, almost all is pumped hydro.

Most future storage will be constructed after the majority of energy produced is from renewable sources.

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