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Climate Rewind: Scientists Turn Carbon Dioxide Back Into Coal

posted by mrpg on Thursday February 28 2019, @08:46AM   
from the don't-dig-it-up-again dept.

janrinok writes:

Arthur T Knackerbracket has found the following story:

Researchers have used liquid metals to turn carbon dioxide back into solid coal, in a world-first breakthrough that could transform our approach to carbon capture and storage.

The research team led by RMIT University in Melbourne, Australia, have developed a new technique that can efficiently convert CO₂ from a gas into solid particles of carbon.

Published in the journal Nature Communications, the research offers an alternative pathway for safely and permanently removing the greenhouse gas from our atmosphere.

Current technologies for carbon capture and storage focus on compressing CO₂ into a liquid form, transporting it to a suitable site and injecting it underground.

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Original Submission

• Re:Energy storage? Re:Energy storage? (Score: 4, Informative) by bradley13 on Thursday February 28 2019, @02:11PM (2 children)

  by bradley13 (3053) on Thursday February 28 2019, @02:11PM (#808107) Homepage Journal

  "Just dig the hole deeper and stack them batteries higher."

  Easier said than done. Energy density of a lithium-ion battery is (according to Wikipedia) somewhere around 500wh/liter. By comparison, the energy density of carbon (assuming it would be burned to CO2) is about 20000wh/liter. Looked at simplistically: batteries are 97.5% wasted space and materials, and only 2.5% actual energy storage.

  If you start talking about national levels of power, you're not talking measly GWh, you talking PWh or more. Aside from the cost of making that many batteries, there just isn't that much lithium available, not in all the active lithium mines on the entire planet.

  Now, your criticisms of their method may well be valid. Still, to solve the energy storage problem on a national scale, we need to produce fuel, not charge batteries. A solid fuel like carbon has the advantage of being relatively inert and safe to handle - as opposed to hydrogen, for example.

  --
  Everyone is somebody else's weirdo.

  Parent

  Starting Score:	1		point
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• Re:Energy storage? (Score: 2) by c0lo on Thursday February 28 2019, @03:00PM

  by c0lo (156) on Thursday February 28 2019, @03:00PM (#808130) Journal

  By comparison, the energy density of carbon (assuming it would be burned to CO2) is about 20000wh/liter.

  Which means that any attempt to abate CO2 by using (renewable) energy is shit - you are gonna waste a lot of energy for little results.

  So, how about using the renewable energy to create better condition for the nature to do what has done for hundred millions of years and capture CO2 as organic matter?
  You know? Something like grow algae and let them capture the sun and use some renewable energy to pump water or otherwise control the process, then filter the algae you grew and use it as compost or biomass for biofuel?

  If you start talking about national levels of power, you're not talking measly GWh, you talking PWh or more.

  Me? It was you that jumped to GWh.
  I said "Energy which I can use to run an algae "pond" to scrub CO2 and sequester carbon as organic fertilizer", don't see how one can expect that me, a single person, to manage GWh.

  there just isn't that much lithium available, not in all the active lithium mines on the entire planet.

  _{You mean available in easy to extract concentrations. Otherwise, the lithium in the sea water is estimated to 230 billion tonnes}

  Still, to solve the energy storage problem on a national scale, we need to produce fuel, not charge batteries.

  Algae fuel [wikipedia.org] is exists already if you aren't concerned about costs (from your "work at even a relatively poor efficiency" I take you are not)

  If the annual biomass production capacity is increased to 10,000 tonnes, the cost of production per kilogram reduces to roughly $0.47 and $0.60, respectively. Assuming that the biomass contains 30% oil by weight, the cost of biomass for providing a liter of oil would be approximately $1.40 ($5.30/gal) and $1.81 ($6.85/gal) for photobioreactors and raceways, respectively. Oil recovered from the lower cost biomass produced in photobioreactors is estimated to cost $2.80/L, assuming the recovery process contributes 50% to the cost of the final recovered oil.

  Speaking for myself, I didn't even had in mind cultivating algae. Something I do intend to do, though, is a small auxiliary hydroponic operation involving Azola [wikipedia.org] (captures nitrogen) and duckweed [wikipedia.org] (five to six times as much starch as corn per unit of area) - I need organics in the soil of a farmlet I bought about 5 years ago.

  --
  https://www.youtube.com/watch?v=aoFiw2jMy-0 https://soylentnews.org/~MichaelDavidCrawford

  Parent

• Re:Energy storage? (Score: 2) by fritsd on Thursday February 28 2019, @04:49PM

  by fritsd (4586) on Thursday February 28 2019, @04:49PM (#808182) Journal

  Tepco ((in-)famous for the Fukushima nuclear plant) was working on Sodium-Sulphur batteries [wikipedia.org] for grid storage.

  Then at least the electrolyte materials are a lot cheaper and more abundant than Lithium.

  Disadvantage is that it needs to operate at elevated temperatures (to melt the Sodium), and that it's of course quite .. reactive .. so you wouldn't want too much of it in 1 location because terrorists.

  Parent