Carbon Capture System Turns CO2 Into Electricity and Hydrogen Fuel (newatlas.com) 155
Researchers at Ulsan National Institute of Science and Technology (UNIST) and Georgia Tech have developed a new system that absorbs carbon dioxide and produces electricity and useable hydrogen fuel. New Atlas reports: The new device, which the team calls a Hybrid Na-CO2 System, is basically a big liquid battery. A sodium metal anode is placed in an organic electrolyte, while the cathode is contained in an aqueous solution. The two liquids are separated by a sodium Super Ionic Conductor (NASICON) membrane. When CO2 is injected into the aqueous electrolyte, it reacts with the cathode, turning the solution more acidic, which in turn generates electricity and creates hydrogen. In tests, the team reported a CO2 conversion efficiency of 50 percent, and the system was stable enough to run for over 1,000 hours without causing any damage to the electrodes. Unlike other designs, it doesn't release any CO2 as a gas during normal operation -- instead, the remaining half of the CO2 was recovered from the electrolyte as plain old baking soda. The research was published in the journal iScience.
Energy budget? (Score:4, Insightful)
Re:Energy budget? (Score:5, Informative)
the hydrogen is in in the "organic electrolyte". the potential energy is in the sodium metal and possibly the electrolyte.
It's not free energy. It's an ordinary and expensive chemical reaction.
Re:Energy budget? (Score:5, Informative)
The paper can be downloaded (no paywall) from here [sciencedirect.com]. Equation 5 "Net equation" is
2Na + 2H+ -> 2Na+ + H2, E0 = 2.71V.
So yes, it works by consuming sodium metal. I am underwhelmed.
How much energy could we get from the metallic sodium if we didn't turn CO2 into NaHCO3 as a side reaction? What is our efficiency at making metallic Na? If these cells are sufficiently cheap, reliable, high power output, and efficient there might be potential for using this for grid scale energy storage in the form of metallic Na. Doing so would have an advantage of energy storage being limited only by your ability to store sodium, so it could work on seasonal timescales. Of course, then you'd have seasonal H2 production which would carry its own storage issues.
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If the CO2 can be converted into Hydrogen and electricity, both of which are useful byproducts of the process, it might be economically feasible to retrofit coal and gas power plants.
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Re:Energy budget? (Score:5, Informative)
The older production method is carbothermal reduction of sodium carbonate, which releases Carbon Monoxide, which will turn into CO2.
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or electrolysis of NaOH, which was the process originally used when Na was isolated.
That process is much better for small scale production of Na (far lower temperature),
but consumes a lot more electricity per g of Na, which is why it was replaced by NaCl
electrolysis.
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I think nature would rather strip oxygen out of the water rather than the chlorine, so you'd end up with oxygen and hydrochloric acid.
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If the CO2 can be converted into Hydrogen and electricity, both of which are useful byproducts of the process, it might be economically feasible
Whoa, whoa, whoa there buddy. Let me stop you right there. There's nothing economically feasible about metallic sodium at the moment. I guess the next step is for someone to figure that step out.
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CO2 cant be converted to Hydrogen cause there are no fucking H atoms in CO2.
The hydrogen comes from water. Water is cheap, the problem here is the sodium electrode. Want to make that coal plant green? They need a water supply (pipes already in place for cooling anyway) and then as much metallic sodium as coal!
Unfortunately, there are no sodium mines. Sodium can be produced from salt, but that needs more electricity than the now green power plant puts out. So this is no solution. Other CO2-cleaning solutions exists, that merely makes energy much more expensive (and so solar/wind en
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That you can't spend a few seconds reading an article is understandable but not even reading the blurb? Bad lazy stupid coward!!
Re:Energy budget? (Score:5, Interesting)
Reading a bit more (I am not a chemist):
"Because the potential of cathodic reaction is closely influenced by the pH of aqueous solution, the dissolution of CO2 renders a favorable electrochemical reaction environmentby acidifying the aqueous solution."
"Thus, notably, this combined cathodicreaction not only utilizes CO2 to generate H2 but also possesses highly efficient reaction kinetics,possibly overcoming the key issue of sluggish discharge rates for common metal-air batteries."
Figure 4 shows this is a rechargeable battery!
"On repeating the discharge-charge process, the cathode potential profile(Ecathode) presents discharging and charging plateau, clearly proving that this system is rechargeable."
"To confirm the reversibility of hybrid Na-CO2cell, the anodic charge profile (electrolysis profile) was observed. Because Na is one of the most abundant elements on earth, Na metal anode could be easily recycled through a charging process in Na-ion-containing aqueous solution, such as seawater. Figure 4A shows an oxidation rotating disk electrode profile for examining whether CO2 was reproduced during the charging process. Generally, the charging process is regarded as the opposite reaction of the discharging reaction. In this work, however, the generated H2 gas from the discharging process is naturally removed on the surface of electrode, and thus the oxidation reaction proceeds as the oxygen evolution reaction (OER) from the water oxidation (Equation 6).
2H2O -> O2(g) + 4H+ + 4e- Eo= 1.229 V"
As this equation does not involve Na, I'm still unclear on how they are regenerating their Na.
Help! Is there a chemist in the house?
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They aren't they are producing sodium bicarbonate. That's where your CO2 and your Na go.
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So yes, it works by consuming sodium metal. I am underwhelmed.
I'm slightly whelmed. Perhaps this could be a solution to soil salinity, or even desalination of sea water. We'd end up with a lot of chlorine, but i'm sure some enterprising person will find a way to monetize that; perhaps Milo Minderbinder could spray it on his cotton and convince people to eat it.
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I think nature would rather strip oxygen out of the water rather than the chlorine, so you'd end up with oxygen and dilute hydrochloric acid.
fireworks show (Score:1)
Sodium metal is a byproduct of production of chlorine, used for lots of things. I once worked on a tug-n-barge tasked with disposing of barrels of sodium metal waste way out in the Gulf of Mexico. It was quite a fireworks show! So the cost of sodium metal is already defrayed somewhat.
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Yes and no, if they are doing it right you don't taste the sodium except in a few special exceptions (pretzels, popcorn, fries) but rather the sodium facilitates the tasting of whatever it is being applied to. A properly salted steak doesn't take like steak with salt, it just tastes like a more flavorful steak.
Contrary to popular belief there IS a correct amount of salt and it is not a matter of personal taste. That said there are individuals who have ruined their palettes by consistently oversalting. The o
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This is not a place to argue with facts and reason or anything similar (if there is any). The current religion is that all and everything is dangerous and we are guilty. The later is especially true if you were the misfortune to be privileged white male or only male or feel male while being something else.....
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And 500 years ago, Paracelsus famously wrote: Everything is poison, and it's only the dose that makes something not poisonous. This is still valid today.
And all your arrogance will not change it. Life is misery, and everything is poisonous.
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Why do you think some people use more salt than others in the first place?
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Lots of reasons. The most likely being that they didn't. They were fed over-salted food coming out of a can as children from an elderly smoker generation that couldn't taste food.
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Happened to me but only selectively. I tend to slightly over salt chicken/turkey soup. I still know where the salt level should be and will salt the pot appropriately but I always add more to my own bowl because I grew up eating Campbells canned chicken soup as a kid.
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I also think there are a lot of dishes that have a wide "salt zone" wherein the dish still tastes okay. People who know how to salt will add in increments until they reach somewhere near the bottom of that range. People who do not will add salt from a recipe or in larger increments getting a result that seems to taste right but contains more. It's possible overtime this desensitizes them to salt.
The elderly have diminished taste buds as well. It is a common practice to replace salt with sugars in the shake
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You've strayed from the topic a bit, but since you're into culinary stuff, I'd recommend Salt, Fat, Acid, Heat [simonandschuster.com] if you haven't read it already. More of a food science book than a cookbook, it gave me a much deeper appreciation of salt and how to properly use it.
There's a lot of good food science in that book, and if you dork out about cooking at all, I'd highly recommend it as a solid reference book to have around. I've tweaked some of the things that I make regularly based on stuff I learned from that book
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https://www.youtube.com/watch?... [youtube.com]
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By all means continue not enjoying food to its maximum potential.
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So what happens to the carbon of the organic electrolyte after the reaction?
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I think nothing. They need a liquid electrolyte around the Na electrode, and it can't be aqueous because that would react violently with the Na. So they have an organic electrolyte into which the Na can dissolve, and then it passes through a membrane into aqueous solution where the rest of the reactions happen.
Re:Energy budget? (Score:5, Informative)
So the energy balance becomes
Na + H2O + CO2 => NaCO3 + H2
0 - 237.1 kJ/mol - 394.4 kJ/mol => -851.0 kJ/mol + 0
-631.5 kJ/mol => -851 kJ/mol
So it works out. The reaction is exothermic and a net 291.5 kJ of energy is released per mole.
But as you point out, the wild card is the Na. The above assumes you can get elemental sodium at zero energy cost. Sodium is extremely reactive and you just don't find it in its elemental state in nature. Depending on how much energy you had to use to refine some sodium compound to create the elemental Na needed for this reaction, it could be a net energy loss.
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The reaction is exothermic and a net 291.5 kJ of energy is released per mole.
We need publication of the net energy balance of the system as a whole. If the energy required to bring the electrolyte and the Sodium metal to the lab is more than that 291.5 kJ/mol (and I'm pretty sure it is), then this is not sequestering Carbon. they're burning the carbon to produce the inputs to the reaction. "50% efficiency" at sequestering the CO2 is meaningless without taking into account the CO2 released to make the reagents.
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There are ways to obtain usable energy that do not involve the production of CO2, like solar, wind, nuclear fission, eventually nuclear fusion. Maybe you've heard of them?
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There are ways to obtain usable energy that do not involve the production of CO2, like solar, wind, nuclear fission, eventually nuclear fusion. Maybe you've heard of them?
Yes, but it also takes carbon to build a solar or wind power system. How much? There is no such thing as a free lunch.
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It is sequestering the carbon. Sodium bicarbonate can be pretty easily stored.
Sequestering carbon (dioxide) isn't about generating power. That's not possible. It's about converting the CO2 to some form that's easy to store, preferably using the least amount of energy possible.
If it were just bringing the ingredients to the carbon scrubber, that would be a massive win. The energy input in this process is making elemental sodium.
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Depending on how much energy you had to use to refine some sodium compound to create the elemental Na needed for this reaction, it could be a net energy loss.
The laws of thermodynamics demand a net energy loss.
From what I understand, the typical way to make metallic sodium at the moment is electrolysis of NaCl, which would consume more electricity than this produces.
However, nothing says that electricity has to come from a CO2-producing source. So this could be valuable as a carbon sequestration technique, which happens to also include a battery.
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Very good review, thanks!
I wonder if there is an unstable compound available that can be expected to yield Na under the right conditions. Because otherwise it looks like the fuel here (Na) is going to be more expensive than the "income" (energy) it is going to help generate.
Re: Energy budget? (Score:2, Informative)
The power has been put in upfront to produce the elementary sodium used as one of the electrodes. Not sure if you remember those nice and impressive basic experiments in school, when the teacher took out a tiny piece of elementary sodium, which much be kept away from water and is typical stored in some inert organic solvent. From the scheme that was posted, I would conclude that the sodium electrode is consumed during the process. Producing elementary sodium is a very energy intense process.
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The storage is never ideal, and the metal quickly tarnishes and contaminates the storage medium. After several months it's not unusual to fish black lumps out of some brown mineral oil. I can't imagine the shelf life of these chemical batteries to be all that great.
It might be the small samples, but it's really expensive to buy sodium too. I'm not sure if the price reflects the energy it takes to produce, the losses in storage, the complexity of safely shipping it, or a little of all of those.
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It might be the small samples, but it's really expensive to buy sodium too. I'm not sure if the price reflects the energy it takes to produce, the losses in storage, the complexity of safely shipping it, or a little of all of those.
Sodium metal is about $3000-4000/tonne at current market rates. Of course that only matters if we know how much Na metal is needed per MwH of storage this battery needs. There are Sodium-Sulfur batteries which the Japanese use but they have the problems you think they do. They explode and catch fire if damaged which creates problems when trying to build really big storage. I would doubt that this new battery will be even as effective as Sodium-Sulfur. The only way this thing is economical is if there i
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Its energy is coming from the reaction of the Sodium metal anode into Sodium Bicarbonate -- NaHCO3. The graphic in the referenced article is clearly showing Sodium ions migrating from the Anode to NaHCO3 in solution, so I call bullshit on their claims it doesn't damage the electrodes.
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I have not read the paper in detail but I assume they add sodium to the "organic electrolyte" around the sodium electrode to supply the reaction and so long as they replenish the sodium in the electrolyte fast enough then the electrode itself won't lose mass.
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That sounds odd... where's the power coming from?
The energy comes from the oxidation of the metallic sodium.
So where does the metallic sodium come from? From burning fossil fuels to reduce sodium carbonate, of course.
They have discovered perpetual motion. Then they just bleed off the excess energy as hydrogen gas.
Global warming is solved! Whew, what should we work on next?
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How about...
Renewable be used in the metallic sodium manufacturing?
None of this is about energy production... Only storage. Batteries aren't production either. Nukes, wind and solar are production. Technically the sun is nuclear too and wind is derived from the effects of solar heating, but....
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Renewable be used in the metallic sodium manufacturing?
If you are generating renewable energy, you can just put that into the grid to displace electricity from fossil fuel. Why use it to create sodium metal, and then just turn around and oxidize the metal back into what you started with? That makes no sense.
The process described in TFA is completely pointless. Sodium metal is made by the reduction of sodium carbonate, using electricity as the energy source. The battery in TFA converts the sodium metal back into sodium carbonate, with the excess energy relea
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The sodium metal isn't consumed so long as sodium is added to the electrolyte. In other words just add salt.
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> In other words just add salt.
The sodium in salt is already oxidized by whatever makes it a salt (e.g. Chlorine, if you use common table salt). This poisons the reaction as the chlorine ions are more oxidative than the carboxyl groups formed from dissolving CO2 in water... Na+ ions aren't going to readily react with anything that wants extra electrons.
=Smidge=
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You might want to learn the difference between ions and atoms, because it makes quite a big difference here.
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Because there is often too much renewable generated to be consumed at the time.
As I said... STORAGE.
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Because there is often too much renewable generated to be consumed at the time.
As I said... STORAGE.
But why not use something efficient instead, so you don't waste most of the energy?
Even if you want to fixate on sodium, there are far better methods, such as sodium ion batteries [wikipedia.org] that have a round-trip efficiency of over 80%.
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a.) Batteries are immobile
b.) batteries are HEAVY
and finally referencing your comment about waste,
c.) moving energy via "the/a grid" is lossey.
It's not the sodium that is important, it's the hydrogen produced and the CO2 capture that is important.
What IS this fetish about batteries!
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But why not use something efficient instead, so you don't waste most of the energy?
Because this includes CO2 sequestration (assuming you get your Na from something like electrolysis of NaCl).
This is a carbon sequestration scheme that happens to include a battery. Not a fantastic new battery.
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Because you cannot always displace the energy into the grid, precisely. In Europe at least they have massive peaks of overproduction of wind power they have to get rid of by selling it at negative prices. Totally not dispatchable. And the reversible hydroelectric plants ability to store electricity is overwhelmed. In the bargain, it is often the nuke plants that reduce their output so it is totally useless.
And in the U.S. the different electricity grids are not even well connected.
Hence a demand for electri
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overproduction of wind power they have to get rid of by selling it at negative prices. ... see below.
It is usually not the renewables that are sold for negative prices
it is often the nuke plants that reduce their output so it is totally useless. :D at least not when you need it in an "dire situation".
No, their power gets sold for a negative price. Because it is cheaper to keep them running and sell the power for a negative price than to power them down and later up again.
Totally not dispatchable
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IF the process is reasonably energy efficient, it could solve several problems at the same time. Renewable power needs storage (except reservoir hydro, which mostly provides its own).
This process is a battery: you store excess power in the form of elemental sodium. When you need that power back, you react the sodium with CO2. Unfortunately you get hydrogen, which you then have to burn in a power plant, adding complication. As a benefit, you get carbon locked up in a stable, easily storable form.
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Very insightful! This is why the Aussies are lining up H2 generation/export.
You're not in the US are you?
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- Because remote places with lots of sunlight (deserts, or close enough) typically don't have a convenient grid connection you can hook into?
So you are going to haul truckloads of sodium carbonate into the desert, use solar energy to convert it into metal + CO2, and then haul out the metal?
If the goal is to make the world's most expensive electricity, this is a good way to go.
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You could pump some sea water into a desert. There are several of them in close proximity to oceans.
It's not a power generation technique, it's a power storage and carbon sequestration technology.
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It's not a power generation technique, it's a power storage and carbon sequestration technology.
Sodium is made this way: Na2CO2 + Energy = 2*Na + CO2
The process in TFA does this: 2*Na + CO2 = Na2CO2 + Hydrogen
The CO2 in the two process CANCELS OUT. ZERO carbon is being sequestered.
The net effect is to convert electricity into extremely expensive hydrogen ... presumably so the H2 can then be converted back into electricity.
If your goal is to time shift the electricity by storing the H2, then you need to also account for the electricity needed to compress or liquify it, making it even more expensive
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Your information seems to be a bit out of date. Sodium was originally made from sodium carbonate, but Wikipedia says most sodium production today is from electrolysis of molten NaCl: https://en.wikipedia.org/wiki/... [wikipedia.org]
Regardless of your caps, you can certainly make sodium from the chloride salt, so the process can sequester net carbon. If you use some sort of partial-availability zero carbon energy source (maybe solar to heat up the NaCl and electrolyze it) then you have a chemical battery (a sodium-air batt
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You're consuming a sodium atom, so it's not free energy. The sodium will need to be replaced in the system in fairly large quantities, but we have a few huge salty water sources that could provide it.
Great news! (Score:1)
Not a capture system. (Score:2)
This isn't really a CO2 capture system because it does nothing to actually capture CO2. Instead, this is a use for captured CO2: batteries. This is a good thing because we need to start pulling billions of tons of the stuff out of the sky.
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This isn't really a CO2 capture system because it does nothing to actually capture CO2
Uh....it converts atmospheric CO2 into sodium bicarbonate (aka baking soda). That makes it a capture system.
Interesting. Now let's see how it scales. (Score:2)
We need more of this kind of research if we're going to successfully attack the problems involved in climate change and excessive atmospheric CO2.
Because gamified economic schemes aren't going to cut it.
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Absolutely. We will need several or many tools to take care of these problems. Economic carrots and sticks are only one method, albeit a proven one, that can help.
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Absolutely. We will need several or many tools to take care of these problems. Economic carrots and sticks are only one method, albeit a proven one, that can help.
Sure, we could hope that a host of technological innovations in battery technology, electric grids, improved solar cells and more efficient turbines can patch together a solution that over time takes the place of fossil fuels at great cost over 30 years (and that doesn't consider fuels or any of the other major sources of CO2 other than electricity). That *could* work even though all the rates of improvements of those technology are nowhere near what we need to replace fossil fuels.
Or we could just use n
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Or we could just use nuclear and take care of all the problems at once doing far less damage to the environment in the process. With nuclear you can cheaply make synthetic fuels to replace gas, diesel and natural gas that renewables can't really do anything about
How can we make synthetic fuel using nuclear plants? At scale to replace gas, diesel and natural gas?
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You could replace gasoline and diesel easily enough. Carbon-neutral synthetic hydrocarbon production is a fairly well refined process, the product is just not economically competitive with the stuff you pump out of the ground, because it requires energy to produce. The US Navy Research Lab developed a demonstration system that made jet fuel.
Making natural gas is even easier, but you probably wouldn't do that as much because most of the places we use natural gas would be fine using the raw electricity.
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Build in sufficient capacity with a non-peaking source like nuclear.
Use excess power production during low-demand times to do things like desalinate seawater and crack CO2 to produce hydrocarbon fuel.
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How can we make synthetic fuel using nuclear plants? At scale to replace gas, diesel and natural gas?
Easy, we just have to build a few thousand nukes.
Per country, of course. Bigger countries more, smaller countries less, of course.
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Environmentalist don't like wind turbines or hydro power plants either they kill the wild life. Wind turbines are illegal where I live, for an individual solar isn't always an option, and hydro power isn't an option. Leaving me with no options as an individual though a wind turbine would be a great investment in my area.
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Solar also kills wildlife.
And the land usage involved can create ecological disruption problems.
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As an individual just putting up panels on my roof isn't feasible unless I want to cut down a bunch of trees and even then it might not be since I live part way up the east side of a hill.
I live in eastern kansas with an average 13.1 mph wind speed for the area though I live between some rolling hills that channel the winds coming off the great plains and get a just little bit better than the average.
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It's not an "either/or" problem.
They can be used together.
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Yes we need to attack the problem in multiple ways. But the evidence is that carbon pricing / taxing (choose your name) can be very effective at improving efficiency and reducing waste - and it's something that can be implemented relatively quickly.
If you have 5 min, this video includes some good reporting of what happened when Australia brought in, and later repealed (for bonkers political reasons), a carbon pricing scheme. And it lists some of tangible changes that it (briefly) made:
https://youtu.be/6fV6
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The problem is, simply implementing such gamified carbon trading systems locally are masturbation.
They don't make a huge dent in the problem.
Unless we're talking universal buy-iin from places like Europe, China and India as well, you're pissing into the wind.
The problem is, China and India aren't ever going to actually implement and follow this.
They'll game it at every opportunity. Or just outright ignore it.
We need to concentrate on real-world engineering solutions for this, because you're not simply goin
CO2 Scrubber. (Score:4, Interesting)
Sell it to NASA.
They've been looking for ways to get rid of captured CO2 for decades. If you can use it to generate electricity too, I'm sure they'll be interested.
Much more likely though - this requires an input (the sodium?) that will cost more to source than you'll ever save.
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Not to worry, electrolysis can be used to separate sodium from salt. Just apply some electricity to some abundant seawater...
Oh, wait...
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And that's where it goes full circle... this doesn't consume the sodium from the expensive sodium metal electrode, it consumes the sodium from the salt you've added to the electrolyte.
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The O comes from the water in one of the electrolytes. That's why this releases hydrogen.
The thing you'd have to add to this system is the Na. Which is not that hard to produce.
Keep in mind the most efficient CO2 scrubber consumes an H2O per CO2 molecule (photosynthesis).
Plant Famine (Score:1)
It takes CO2 as an input? But that's food for plants! Won't someone please think of the plants?! They remove greenhouse gas from the atmosphere, leave them alone! /s
Useless contraption? (Score:1)
This basically uses Na (sodium), water and CO2 to produce NaHCO3 + H2 (hydrogen) + electricity.
But consider the following. Just react Na with water and you get NaOH + H2, plus some heat (and usually some explosions but that can be worked around). NaOH can react quite easily with CO2 in aqueous solution to form NaHCO3, netting you virtually the same result. Well, except that you get heat instead of electricity, and of course electricity is more useful, I agree.
The problem is, to capture CO2 with this process
This Method is Uses a TON of Energy (Score:5, Informative)
Carbon Dioxide is a very stable molecule, getting it to react requires a large amount of input energy. While TFA make it sound like we are gaining energy from this process, there is no free lunch.
The reason why this reaction produces energy is because it is consuming pure metallic sodium and converting it to sodium bicarbonate. Pure sodium does not exist in nature at all, because it is so reactive. Manufacturing metallic sodium is an extremely energy intensive process that involves splitting molten salt (Sodium Chloride) into sodium and chlorine gas using electrolysis. This is Downs' Process [wikipedia.org]. The sodium bicarbonate that this process produces has industrial applications, some of them involve reactions that release the CO2 we just spent of ton of energy capturing back into the atomsphere, baking breads and cakes for example.
Any method that involves electrolysis is going to use a ton of energy. If we are going the electrolysis route, then might as well produce hydrocarbons using electrolysis to convert water and CO2 to syngas, which can then be used to produce hydrocarbons via the Fischer–Tropsch process [wikipedia.org]. Hydrocarbons are way more useful from an industrial standpoint. The most obvious is we can burn them to power legacy Internal Combustion Engine vehicles, which closes the carbon feedback loop; but that is just one use. Hydrocarbons can be used as feedstock for all kinds of organic chemistry processes, we can make tons of plastics, polymers, lubricants, carbon fiber, etc. All of these things cannot be produced without oil mining today. The nice thing about hydrocarbon synthesis is that it can replace mined fossil fuels in all our existing petrochemical manufacturing processes. The same cannot be said about baking soda.
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I think we will see a shift from energy conservation and efficiency to choosing processes which can use excess electricity that isn't continuously available. Energy is not scarce at all. Non-renewable sources are scarce, but solar in particular is not scarce. Instead of storing energy and trying to tailor electricity production to closely follow demand, dirt cheap solar panels will allow us to produce enough electricity in practically all weather conditions (assuming a big enough electrical grid is availabl
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Just keep adding more energy until the product needed is produced and the energy politics works.
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Thanks for this. Every time you see something like this which isn't leading with the news of how efficient the process is, you know it consumes too much energy to be workable. If it were actually useful, that would be the headline.
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It works if you can get alternative energy. As usual, energy is the bottleneck. Humanity can do pretty much anything if it can get enough clean energy.
Distilling seawater in monster distilleries is a cheap solution for fresh water...with enough such energy.
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It works if you can get alternative energy.
No, it works if you can get free energy, but you can't. Alternative energy might be the cheapest energy, but we still have lots of other places to apply it. Also, the first place you'd put it would be reducing carbon release, by shutting down plants which are emitting CO2. That's going to be more efficient than putting the genie back into the bottle.
There is no free lunch (Score:3)
Transforming CO2 in something else requires an amount of energy comparable to the creation of that CO2. So unless this device gets its energy from an otherwise inaccessible (or not efficiently accessible) source, this is not a solution for anything as long as we're still producing CO2 for energy because obviously, it's a better idea to not turn on this device and in turn shut down a CO2 source. Only once we have eradicated all fossil fuel use, using energy to take CO2 out of the system begins to make sense.
That is: unless the energy powering this thing (the energy making metallic sodium if I understand correctly) is obtained in an otherwise not (efficiently) accessible means. I don't know how metallic sodium is created, but if we could use concentrated solar power for that, which is potentially way more efficient than PV, this might actually make some sense. But other than that, in general, there's no free lunch.
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You could actually. You can get sodium from cracking the sodium chloride in sea water. You can do that using electricity (input from PV or wind) or thermally (concentrated solar). Most current production is a bit of both, you liquefy the salt and then electrolyse it.
Efficient carbon sequestration can be useful even if it's not quite as efficient as turning off a carbon source. You can use excess peak renewable energy, geographically limited renewable energy (like geothermal or solar in the desert) or you mi
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The energy input is the creation of metallic Na, which from my understanding is usually done by electrolysis of NaCl.
So if one was going to use this as part of a carbon sequestration scheme, you'd want to use excess electricity from non-CO2 producing sources to electrolyze NaCl, transport the battery somewhere useful, then have it capture CO2 while it's being a battery.
Interesting Technology - Questionable approach? (Score:1)
This is interesting technology, no question. For the situation of more CO2 in the atmosphere than may be healthy, this isn't going to be much help if any. Nor will it add to the usable energy resources of technological humans.
Basically, interesting technology being spinmeistered into a salvation that it isn't.
As a battery, this is generating energy by oxidizing sodium metal, and removing the reaction products. Obtaining the reduced sodium (ie the metal) takes energy, as you can not mine sodium on earth. So
Fake News (Score:1, Redundant)
If real, this can be used with methane (Score:2)
Solv3 (Score:3)
We have a solution: fast-growing plants buried in non-biodegrading landfills. Or used as construction if wood. Hint: "Running out of landfill space" is leftover 1970s innumeracy, and chemical leeching isn't an issue.
...recovered as plain old baking soda... (Score:2)
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The sodium is a pain in the ass to recovery. But you can add a little acetic acid to the sodium bicarbonate and you can get the CO2 back easily enough. (and turn your useful vinegar into less valuable acetate)
NaHCO3 + CH3COOH --> CO2 + H2O + Na+(aq) + CH3COO-(aq)
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From my skimming of the paper, they'd be getting replacement sodium from sea water, not from the sodium bicarbonate which they produce. That would be sequestered somewhere.
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From my (not a chemist) reading of the paper:
If you have a battery which is consuming sodium to produce electricity, you want the electrolyte around the cathode to be acidic, and the reaction will be producing OH-, neutralizing acids. Continuously dissolving CO2 into this water produces a source of acidity, so the CO2 not only makes the battery works better, but it simultaneously sequesters the CO2 as NaHCO3.
I think this really is the core of the proposal - make the battery work better and sequester CO2 at
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Out of curiosity, where are you located?
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Ok, then rising sea levels ain't that big a problem for you, I have to give you that. Actually, with a hint of luck it might even increase your real estate soon.