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I'm fact checking the statement: "There isn't enough Lithium in the planet (Earth) to store enough energy to make it 4 months through the Winter" here: https://youtu.be/fzzWVLSPgK4?t=192

What assumptions need to be made to answer this question, and what is the answer, based on these assumptions?

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    I don't know the answer, but why would you need to store 4 months' worth of energy? Plenty of wind and hydro power available in the winter.
    – andyyy
    Oct 5, 2022 at 9:21
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    Also, thinking further about it, for longer term storage, flow batteries would be more appropriate anyway. So perhaps the question should really be about the abundance of Vanadium.
    – andyyy
    Oct 5, 2022 at 10:01
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    Why fixate on renewables that need batteries? Inherently safe, next-generation nuclear, preferably MSR, is the way to go, actually.
    – Life5ign
    Oct 11, 2022 at 2:35
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    There're way more great energy storage ideas, and each works for a different use. Wanna heat your house? Pump excess energy in an insulated silo full of sand, then retrieve the heat over the winter. etc, pp.
    – Erik
    Oct 18, 2022 at 7:04
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    Read rethinkX. The cheapest strategy is to overproduce electrity when it is easy and have a small amount of storage. Or watch a video about it youtube.com/watch?v=UUySXZ6y2fk Dec 10, 2022 at 21:20

2 Answers 2

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TL/DR Yes, but it is meaningless. The meaningless is well covered by juhist's answer.

Lithium in the earths crust: Estimates for the Earth's crustal content range from 20 to 70 ppm by weight. Middle = 55/1,000,000

Mass of Earths Crust: Earths crust is 2.3-2.8 *10^19 tonnes Middle = 2.55 * 10^19 tonnes or 2.55 * 10^22 Kg

(2.55*10^19) * (55/1000000) = 1.4 * 10^15 tonnes or 10^18 Kg

Lithium in a battery: 7% Li

Electricity in a battery: 360 to 900 kJ/kg Middle = 630 * 10^3 J/Kg

Electricity stored by all Lithium as batteries:

(1.4 * 10^18)/0.07 * (630 * 10^3) = 1.26 * 10^25 J

Energy use: The annual global energy consumption is estimated to 580 million terajoules = 5.8 * 10^20, so 4 months = 1.45 * 10^20

Therefore there is about 100,000 times as much Lithium in the earths crust alone than it would take to store 4 months worth of electricity.

This is meaningless from both sides; batteries are useful for dealing with differences between demand and supply over time scales of seconds to hours, and perhaps longer in the future, but no one would try and store four months worth of electricity in batteries. On the other side it would be completely impossible to extract all Lithium from the earth's crust.

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  • The calculation looks good. Can you expound on your statement that no one would store 4 months of electricity in batteries? Do you mean they would store less (perhaps the difference between total average demand and average supply from renewables during all of Winter, minus the amount of energy obtained elsewhere), or they wouldn't store it at all?
    – Life5ign
    Oct 5, 2022 at 18:50
  • @Life5ign I have expanded that point. Does it make sense now?
    – User65535
    Oct 5, 2022 at 21:05
  • This answer isn't very useful. We can only extract highest grade lithium ores and brines near enough the surface of this planet. Calculating the total amount of lithium in this planet and using that figure, I'm afraid, isn't useful, because we can't access all of that -- as the answer correctly states.
    – juhist
    Oct 6, 2022 at 16:44
  • @juhist yes it is. it's a fact check on an arbitrary statement, giving the most possible generous amount of lithium: all of it, not only the amount that could be mined; the ad extremum is the point, to show that the statement is wildly incorrect (even though I agree with him on other points). If there were enough in the the crust, the answer could be further refined to reflect how much could be mined. Do you see how the simpler, extreme calculation is more powerful, faster, and by definition rules out the more complicated "how much can we mine?" calculation. That is not necessary.
    – Life5ign
    Oct 6, 2022 at 21:18
  • @juhist I tried to address that in the last paragraph, without adding too much text critiquing the question rather than answering it.
    – User65535
    Oct 6, 2022 at 21:27
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No there isn't, but we don't need lithium for that. The lithium reserves are barely adequate to make all cars electric. They are not adequate for grid energy storage.

We need about 500 hours worth of storage (three weeks, not four months, since presumably in areas with real winter, power production is predominantly wind power, and presumably electric grids of tomorrow are strong to allow transferring electricity from windy areas to non-windy areas) to allow electricity usage during long large-area calm periods in winter when neither solar power nor wind power is available in big enough quantities. If average annual energy use per person is 10 MWh in a developed world of tomorrow, and world future population will reach 10 billion, then we need 100 PWh of energy per year. That's about 11000 gigawatts assuming constant energy use.

So 500 hours * 11000 gigawatts is 5.5 PWh. (Actually the real figure is slightly larger because 11000 gigawatts assumes constant energy use and the 11000 gigawatts should be adjusted for momentary higher-than-normal energy use, but in any case, the figure is below 10 PWh).

There is a paper in Nature Communications that shows we can store more than 5.5 PWh, in fact we can store 17.3 PWh, at reasonable cost using pumped hydroelectricity. So grid energy storage is possible.

However, what about lithium? A plug-in hybrid (10 kWh) requires about 1.6 kg of lithium. So to store 5.5 PWh, we need 880 billion kilograms or 880 megatonnes of lithium. Unfortunately, lithium reserves are between 17 and 21 megatonnes, and in 2020 resources were 80 megatonnes. Nowhere close to what is needed.

Even if the paper in the highly rated Nature Communications journal is wrong and we can't construct enough hydroelectric energy storage at a reasonable cost, then there's another possibility: it's possible to create hydrogen from water using electrolysis and burn that later to electricity in internal combustion engine or gas turbine power plants. That has a round-trip efficiency of about 37%, in contrast to 80% round-trip efficiency of pumped storage hydroelectricity.

Also, battery energy storage is so expensive that storing the 5.5 PWh in batteries is nowhere near competitive to storing it in pumped storage hydro or as hydrogen stored underground as compressed gas.

Only a fool would create electricity with 100% solar power, and then try to use 4-month long storage to allow using electricity in winter. The solution is not solar, it's wind. And only a fool would use batteries for long-term energy storage. For short-term use (charge at every day with solar, discharge at every night) batteries are ok.

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