3 ms·
> What reasoning is holding us up? People turn their lights on when the sun goes down, and efficient energy storage is the holy grail. Also fun back of the na
by qppo 6y ago
> What reasoning is holding us up?
People turn their lights on when the sun goes down, and efficient energy storage is the holy grail.
Also fun back of the napkin math with overestimates, if we have a totally efficient Li+ battery with 0.25 kWh/kg energy density, and converted all the world's 40 billion kg of lithium in the crust and oceans to batteries, we'd get roughly 10 TWh of energy storage capacity. Which is enough to power California for 19 days (we generate around 200TWh annually).
In reality we only have access to a tiny fraction of the world's Lithium reserves, batteries aren't that efficient, they're heavy, dangerous, and all that makes for an expensive technology ill suited for grid energy storage (and alternatives like lead-acid are even worse).
Energy storage on the grid is going to look more like dams and reservoirs in the mountains than battery arrays. Even that's not great, ideally we'd invest more into nuclear energy for generating clean power on demand.
- philipkglass 6y agoAlso fun back of the napkin math with overestimates, if we have a totally efficient Li+ battery with 0.25 kWh/kg energy density, and converted all the world's 40 billion kg of lithium in the crust and oceans to batteries, You are confusing present estimates of lithium resources (a term of art used in the mining industry) with terrestrial abundance. Your estimate of 40 billion kilograms roughly corresponds to the USGS estimate of world lithium resources in 2015 (39.9 million tons): Mineral Commodity Summary, Lithium, 2015 [1]: https://s3-us-west-2.amazonaws.com/prd-wret/assets/palladium/production/mineral-pubs/lithium/mcs-2015-lithi.pdf https://s3-us-west-2.amazonaws.com/prd-wret/assets/palladium... Note that this year it has risen to 80 million tons: Mineral Commodity Summary, Lithium, 2020: Owing to continuing exploration, identified lithium resources have increased substantially worldwide and total about 80 million tons. https://pubs.usgs.gov/periodicals/mcs2020/mcs2020-lithium.pdf https://pubs.usgs.gov/periodicals/mcs2020/mcs2020-lithium.pd... And at the turn of the millennium identified resources were about 13 million tons: Mineral Commodity Summary, Lithium, 2001: https://s3-us-west-2.amazonaws.com/prd-wret/assets/palladium/production/mineral-pubs/lithium/450301.pdf https://s3-us-west-2.amazonaws.com/prd-wret/assets/palladium... The Earth's mass changes negligibly over a few decades. The reason lithium resource estimates change so much over a short time is that people have put in the effort to identify and quantify specific sources of lithium. That's what converts preexisting geology from not-a-resource into what miners call a resource. In generic geochemical terms, the Earth's crust is estimated to contain 17-20 parts per million of lithium by mass: https://en.wikipedia.org/wiki/Abundance_of_elements_in_Earth%27s_crust https://en.wikipedia.org/wiki/Abundance_of_elements_in_Earth... If the mass of Earth's continental crust is 2.1 * 10^22 kg, as given in [2], then lithium in continental crust masses about (2.1 * 10^22) * (17 / 10^6) = 357,000,000,000,000,000 kilograms, or 357 trillion tons. There's another couple hundred billion tons of lithium dissolved in the oceans. [1] USGS lithium statistics and annual reports from https://www.usgs.gov/centers/nmic/lithium-statistics-and-information https://www.usgs.gov/centers/nmic/lithium-statistics-and-inf... [2] https://ui.adsabs.harvard.edu/abs/2007AGUFM.V33A1161P%2F/abstract https://ui.adsabs.harvard.edu/abs/2007AGUFM.V33A1161P%2F/abs...
- akiselev 6y agoAccording to [1], a standard 2 Ah 18650 Li-ion cell has something like 0.6 grams of lithium. (2.0 Ah * 4.2 V / 0.0006 kg of lithium) works out to 14 kWh/kg or 560 TWh of capacity. That one battery chemistry alone would be enough to power the entire world for a week. Once you eliminate nonessential industrial power consumption - aka bring your own power storage or shut down machinery with the sun - the amount of lithium we'd need to store to make a transition to solar/wind feasible would be far smaller than global reserves. Edit: as noted by phillipkglass, this math is moot [1] https://batteryuniversity.com/learn/archive/is_lithium_ion_the_ideal_battery https://batteryuniversity.com/learn/archive/is_lithium_ion_t...
- java-man 6y agoAlso, we don't have to limit ourselves to lithium. Li makes sense in vahicular applications, but the grid storage could be perfectly fine with Na or any other technology. Here is, for example, a sodium ion chemistry based on prussian blue: [0] https://natron.energy/technology/ https://natron.energy/technology/
- notJim 6y agoAre you saying 19 full days of energy storage? Why do we need 19 days? Isn't it more like N hours per day, which can be recharged overnight and the following day? This seems like a very disingenuous presentation of this information.
- Gibbon1 6y agoI remember seeing academics analysis of various storage methods that showed how none of them could be scaled up to store 7 days worth of energy. And thus solar and wind were infeasible. There were two problems. One he was using 7 days worth of storage. It's true that in the fossil fuel industry 7 days of storage is standard. But that's because coal/oil/gas have supply chain issues to deal with. So he was intentionally increasing the required storage 10 fold. The second. He studiously avoided any mention of thermal storage methods. Or using natural gas as a back up. Both of which can be scaled up to meet his 7 day storage requirement.
- Gibbon1 6y agoI see I pissed someone off. Whatever, you are who you are. https://www.pv-magazine.com/2020/05/22/borehole-thermal-energy-storage-for-solar/ https://www.pv-magazine.com/2020/05/22/borehole-thermal-ener...
- mrj 6y agoInterestingly, batteries don't have to be lithium-based. https://qz.com/1355672/stacking-concrete-blocks-is-a-surprisingly-efficient-way-to-store-energy/ https://qz.com/1355672/stacking-concrete-blocks-is-a-surpris...
- idoh 6y agoThe point still stands that storing energy in chemical batteries for CA-levels of usage does not math out.
- paul_f 6y agoWe need to quickly get to the next generation chloride ion battery batteries! A whole lot more salt lying around than lithium.