In November, the Paris Climate Agreement goes into effect to reduce global carbon emissions. To achieve the set targets, experts say capturing and storing carbon must be part of the solution. Several projects throughout the world are trying to make that happen. Now, a study on one of those endeavors, reported in the ACS journal Environmental Science & Technology Letters, has found that within two years, carbon dioxide (CO2) injected into basalt transformed into solid rock.
Lab studies on basalt have shown that the rock, which formed from lava millions of years ago and is found throughout the world, can rapidly convert CO2 into stable carbonate minerals. This evidence suggests that if CO2 could be locked into this solid form, it would be stowed away for good, unable to escape into the atmosphere. But what happens in the lab doesn't always reflect what happens in the field. One field project in Iceland injected CO2 pre-dissolved in water into a basalt formation, where it was successfully stored. And starting in 2009, researchers with Pacific Northwest National Laboratory and the Montana-based Big Sky Carbon Sequestration Partnership undertook a pilot project in eastern Washington to inject 1,000 tons of pressurized liquid CO2 into a basalt formation.
After drilling a well in the Columbia River Basalt formation and testing its properties, the team injected CO2 into it in 2013. Core samples were extracted from the well two years later, and Pete McGrail and colleagues confirmed that the CO2 had indeed converted into the carbonate mineral ankerite, as the lab experiments had predicted. And because basalts are widely found in North America and throughout the world, the researchers suggest that the formations could help permanently sequester carbon on a large scale.
Similar results were found in Iceland.
Does injecting CO2 into rock really make more sense than not putting it into the atmosphere in the first place?
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Earlier this week, Y Combinator, which has backed companies like Airbnb and Reddit, put out a request for startups working on technology that can remove carbon dioxide from the atmosphere.
"It's time to invest and avidly pursue a new wave of technological solutions to this problem — including those that are risky, unproven, even unlikely to work," Y Combinator's website says.
Y Combinator is looking for startups working on four approaches that they acknowledge "straddle the border between very difficult to science fiction" — genetically engineering phytoplankton to turn CO2 into a storage-ready form of carbon, speeding up a natural process in which rocks react with CO2, creating cell-free enzymes that can process carbon, and flooding Earth's deserts to create oases.
Sam Altman, the president of Y Combinator, acknowledged that these ideas are "moonshots," but said that he wants to take an expansive approach to the issue.
Related: Negative Emission Strategy: Active Carbon Capture
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A Startup is Pitching a Mind-Uploading Service That is "100 Percent Fatal"
Carbon Capture From Air Closer to Commercial Viability
Y Combinator Spreads to China
Lab-Made Magnesite could be Used for CO2 Capture
NASA Announces CO2 Conversion Challenge, With Up to $750k Awards
(Score: 0) by Anonymous Coward on Sunday November 20 2016, @10:07AM
So, how much energy does it require to put all this carbon into the ground? How easy would it be to extract it again if we would need it in a far future?
(Score: 2) by maxwell demon on Sunday November 20 2016, @11:14AM
You can get the CO2 back from the rock by just adding acid.
The Tao of math: The numbers you can count are not the real numbers.
(Score: 3, Insightful) by Ellis D. Tripp on Sunday November 20 2016, @04:12PM
But why would we want it back? The useful carbon has already been oxidized, so there is no energy to be had from CO2, which is essentially the "ash" from burning fossil fuels...
"Society is like stew. If you don't keep it stirred up, you end up with a lot of scum on the top!"--Edward Abbey
(Score: 0) by Anonymous Coward on Sunday November 20 2016, @04:18PM
I asked the question. I also don't know why we would need it, at this time. But there might be a point in the future (even if it's 10.000 years in the future) that we might have a need for it. Making it completely inaccessible would be a wrong decision.
(Score: 2) by butthurt on Sunday November 20 2016, @11:31PM
Carbon is an essential part of plastics and every living thing. Carbon nanotubes and diamond nanothreads are among the materials being considered for building space elevators.
(Score: 2) by stormwyrm on Monday November 21 2016, @02:35AM
It's material for the Sabatier reaction [wikipedia.org] which can convert hydrogen and carbon dioxide into methane. If you had a cheap and renewable source of electricity, e.g. wind power or solar, you could use any excess electricity to split water into hydrogen and oxygen, then convert the hydrogen into methane with the Sabatier reaction, storing the excess energy on days when there are strong winds or very bright sunshine. Then burn the stored methane in a traditional gas-fired plant during lean times when the sun doesn't shine or the wind doesn't blow, and try to capture as much of the carbon dioxide exhaust as possible for further reuse to make more methane when the sun comes out of the clouds again. You might ask why not just use and store the hydrogen directly, but do remember that hydrogen storage and transport is a non-trivial task, and has many unsolved engineering difficulties. Methane storage and transport on the other hand is pretty much a solved problem. I have a cylinder of stored methane in my kitchen that I use as cooking gas. The petroleum industry transports methane around the world all the time. Just about any petrol engine can be readily converted to use methane instead.
Numquam ponenda est pluralitas sine necessitate.
(Score: 2) by choose another one on Sunday November 20 2016, @12:47PM
The more interesting question is does the process require 24/7 power to run. If not, it can be supplied from excess renewable power that can't be used on the grid, and you can think of it as a kind of electricity storage (dig stuff out of the ground and burn it when solar/wind is low, put stuff back into the ground when you have excess solar/wind). If it needs 24/7 uninterrupted power then it is another datacentre / telco / blast furnace - part of the problem rather than the solution.
(Score: 2) by butthurt on Monday November 21 2016, @12:06AM
A National Renewable Energy Laboratory estimate said that a 600 MW coal-fired power plant could, with geological carbon sequestration, produce a net 457 MW of electricity. They estimated that the 600 MW capacity could be achieved by consuming 16% more fossil fuel, with a 71% reduction in atmospheric carbon dioxide emissions. They favour the idea of burning biomass for electricity, combined with geological sequestration, which would, on balance, remove carbon dioxide from the atmosphere.
https://www.bioenergykdf.net/system/files/Net%20Energy...Life%20Cycle%20Approach.pdf [bioenergykdf.net] (the "..." is part of the URL)
(Score: 2) by hash14 on Monday November 21 2016, @12:44AM
The study in question demonstrates that gaseous carbon dioxide can be stored away in basalt. Gaseous carbon dioxide is fairly useless and easy to create anyway (burning any organic material would probably achieve this), so it probably is not a major issue.
(Score: 2) by hash14 on Monday November 21 2016, @12:46AM
Correction: the process uses liquid CO2, not gaseous, although it is probably trivial to convert from one to another (though I am not sure myself). But that may mean that the process requires more energy than I would have thought originally.
(Score: 2) by Reziac on Monday November 21 2016, @02:57PM
I'd bet the work required to inject it creates, if one backtracks it completely, about double the CO2 of what's being stored.
In any event, higher CO2 is a good thing, not a problem. Because it's what plants live on, it greens the Earth and improves crop yields thus reducing hunger and poverty, and per the un-massaged data, has zilch to do with global warming.
This is worth a watch no matter which side you're on:
https://www.youtube.com/watch?v=4LkMweOVOOI [youtube.com]
(Ranker is perhaps being dense on purpose, given that he's a radical environmentalist.)
And there is no Alkibiades to come back and save us from ourselves.
(Score: 3, Insightful) by Anonymous Coward on Sunday November 20 2016, @10:39AM
> Does injecting CO2 into rock really make more sense than not putting it into the atmosphere in the first place?
Think of it like taking medication to counter your obesity. Make sense now?
(Score: 1) by garrulus on Sunday November 20 2016, @11:12AM
nt
(Score: 1, Informative) by Anonymous Coward on Sunday November 20 2016, @02:05PM
One barrel of oil is the energy equivalent of 2 large trees.
Oil consumption per day in the table below. You do the math on how many trees we need to plant.
1 United States 19,396,000 2015.
2 China 11,968,000 2015.
3 India 4,159,000 2015.
4 Japan 4,150,000 2015.
5 Saudi Arabia 3,895,000 2015.
6 Brazil 3,157,000 2015.
7 Russia 3,113,000 2015.
8 South Korea 2,575,000 2015.
9 Germany 2,338,000 2015.
10 Canada 2,322,000 2015.
(Score: 1) by khallow on Sunday November 20 2016, @02:57PM
One barrel of oil is the energy equivalent of 2 large trees.
We're not interested in energy equivalent. We're instead interested in carbon content.
From here [epa.gov], CO2 contribution from a barrel of oil is 0.43 metric tons CO2 per barrel of oil (calculation is in section titled "Barrels of oil consumed").
From here [typepad.com], the carbon content of a 12 meter tall sycamore tree was calculated and determined to be 2 metric tons roughly (roots, leaves, and all at max foliage). That's roughly 7 metric tons of CO2 when fully burned. That's 16-17 times as much CO2 instead of merely twice. It's still an enormous number of trees, but an order of magnitude less than you claimed.
(Score: 2) by TheLink on Sunday November 20 2016, @05:10PM
We're not interested in energy equivalent. We're instead interested in carbon content.
More relevant is CO2 absorption per day of trees.
You can burn an entire 2 ton tree in a day but it doesn't grow to even half that size in one day. So the enormous number of trees required is likely magnitudes more than you imply with your calculations.
Remember those numbers are barrels per _day_ not per year or decade. Not all of those barrels of oil are burnt per day, but a substantial percentage does get burnt every day.
So I'm wondering if this CO2 injection method can scale. Can it take the CO2 output of a typical power plant without consuming too much energy?
(Score: 1) by khallow on Sunday November 20 2016, @07:07PM
You can burn an entire 2 ton tree in a day but it doesn't grow to even half that size in one day. So the enormous number of trees required is likely magnitudes more than you imply with your calculations.
Not sure where you're going with that since one can grow lots of trees (example was 4 metric ton tree which is 50% carbon BTW) at a time and they'll steadily consume carbon over the course of a tree's lifespan. The real problem as you said is not the length of time it takes to grow trees, but rather the enormous quantity of carbon dioxide that one needs to sink.
(Score: 2) by TheLink on Monday November 21 2016, @09:48AM
You said:
We're not interested in energy equivalent. We're instead interested in carbon content.
That's roughly 7 metric tons of CO2 when fully burned. That's 16-17 times as much CO2 instead of merely twice. It's still an enormous number of trees, but an order of magnitude less than you claimed.
But that's incorrect and missing the forest for the trees. Neither the carbon content nor the effective CO2 locked up is relevant. As I said: More relevant is CO2 absorption _per_day_ of trees. You could have a 4 ton hardwood tree but if it absorbs CO2 at a low rate and takes 200 years to reach that size it barely counts.
Not sure where you're going with that since one can grow lots of trees
Never said we couldn't grow lots of trees. My point is can we grow enough to absorb the CO2 from the millions of barrels of oil burnt per _day_?
Those oil consumption figures are not per year, they are per day. The time scales for trees are typically "year" or even years than "day".
These sites say a tree can absorb 48 pounds of CO2 per _year_:
https://projects.ncsu.edu/project/treesofstrength/treefact.htm [ncsu.edu]
http://www.arborenvironmentalalliance.com/carbon-tree-facts.asp [arborenvironmentalalliance.com]
So one barrel of oil per day = 0.43 metric tons CO2 per day= 947.9877 pounds per day.
One tree at 48 pounds/per year = 0.131506849 pounds per day
So you need about 7200 trees to counter each barrel of oil burnt. Let's assume 40 million barrels of oil burnt per day worldwide (US and China combined use 30 million barrels of oil per day). So you need an _additional_ 288 billion trees.
Apparently there are 3 trillion trees in the world. A 10% increase is probably doable, but how long will it take to plant 300+ billion trees (not all will survive), and where will you plant them?
If it would take a very long time then keep in mind that within that time we are very likely to run out of cheap oil and stop burning so much of it.
(Score: 1) by khallow on Monday November 21 2016, @06:02PM
A 10% increase is probably doable, but how long will it take to plant 300+ billion trees (not all will survive), and where will you plant them?
Which is a fine point. But we need to keep in mind that IF we have space for them, it's just not that hard to plant that many trees with a reasonable factor of excess to cover the ones that don't survive. I think you could get all those trees planted inside of five years.
(Score: 2) by TheLink on Tuesday November 22 2016, @09:07AM
Assuming 600 trees per acre - https://www.state.sc.us/forest/nurspa.htm [state.sc.us] you'd need 2 million square km. That's a bit more than the entire land area of Mexico. Just getting/preparing that amount of land could take a while and a lot of money. I'm sure we have that much spare space in the whole world but it might take longer than 5 years to just to get that land and projects started. You wouldn't need all of it at once but you'd still need to acquire and prepare it at a high rate if you actually want to do it within 5 years. You'd need about 80000 additional tree planters assuming each person can do about 15000 seedlings per week.
FWIW the Gobi Desert is "only" 1.3 million square km. Imagine all the environmentalists protesting if China somehow managed to destroy the entire desert with trees: https://en.wikipedia.org/wiki/Green_Wall_of_China#Measuring_success [wikipedia.org]
http://www.bbc.com/news/science-environment-35496350 [bbc.com]
Note that that is a closer to a 70 year project than a 5 year one. So if it's going to be a 300 year project we'd probably have burned up most of the cheaper oil and would be locked in to the consequences for decades by then.
(Score: 1) by EETech1 on Sunday November 20 2016, @10:37PM
It's crazy to think that a 300-pound barrel of oil can produce 950 pounds of carbon dioxide when burned!
I had no idea that you produced three times as much carbon dioxide in the exhaust as fuel into the burner.
Wow...
(Score: 2) by butthurt on Sunday November 20 2016, @11:41PM
It's because a carbon atom has a mass of 12 atomic mass units, but an oxygen atom has a mass of ~16 atomic mass units, so in a CO2 molecule most of the mass is due to the oxygen. Most of the mass of petroleum is due to the carbon in it.
(Score: 2, Interesting) by EETech1 on Monday November 21 2016, @03:49PM
I understand the chemistry involved, i just never thought about it in tons per barrel.
With a coal plant, seeing tons of carbon dioxide being emitted makes sense, but seeing the numbers for a barrel of oil really surprised me.
It really drives home the fact that we need to stop burning oil!
Cheers!
(Score: 0) by Anonymous Coward on Monday November 21 2016, @10:38AM
Let's see:
Oil is mostly hydrocarbons. Hydrocarbons, as the name already says, are made of carbon and hydrogen (other than methane which is gaseous and therefore not part of oil) and have at most three hydrogen atom. Let's go to the upper limit and assume three hydrogens per carbon (despite that the average is way below, but then, this may compensate for other substances).
The mass of an atom is basically determined by the number of nucleons; in forst approximation, each nucleon has the same mass, and we will ignore the mass defect.
The by far most common carbon isotope has 12 nucleons. Normal hydrogen has only one nucleon. So an upper estimate of the mass of a certain amount of oil is 15 nucleon masses per carbon atom.
Carbon dioxide is made of carbon and oxygen (the oxygen being taking from the air on burning). In particular, carbon dioxide is CO2, so it's made of 1 carbon atom and two oxygen atoms. A normal oxygen atom has 18 nucleons, therefore the mass of a carbon dioxide molecule is 2×18+12=48 nucleon masses.
Now when perfectly burning oil, every carbon atom gives one carbon dioxide molecule. So the total mass of carbon dioxide from burning oil is 48 nucleon masses per carbon atom.
So 15 nucleon masses of oil give 48 nucleon masses of carbon dioxide. That is the mass of carbon dioxide produced by burning the oil is by a factor 48/15 = 3.2 larger than the mass of oil we started with.
That is, burning 300 pounds of oil gives about 3.2 × 300 pounds= 960 pounds of carbon dioxide.
(Score: 3, Interesting) by mendax on Sunday November 20 2016, @05:56PM
I prefer the idea of planting trees, especially when one considers how useful they are. Not only are they beautiful, they can be turned into many useful products such as houses, books, toys. I like the idea of someone considering the building, funding, and stocking of a library because it is a carbon repository. Of course, we'll need a lot of libraries in order to make a dent in the overall carbon footprint.
It's really quite a simple choice: Life, Death, or Los Angeles.
(Score: 1) by nethead on Sunday November 20 2016, @06:43PM
When my wife complains that I haven't broken down and recycled all the damn Amazon boxes I just tell her it's carbon sequestration.
How did my SN UID end up over 3 times my /. UID?
(Score: 2) by mendax on Monday November 21 2016, @04:42AM
Well, it is!
It's really quite a simple choice: Life, Death, or Los Angeles.
(Score: 3, Interesting) by t-3 on Sunday November 20 2016, @07:43PM
(Score: 0) by Anonymous Coward on Sunday November 20 2016, @08:46PM
What fun! We get to deny the laws of physics in coming up with solutions. I propose we increase the size of the earth by 2x. More space for everyone and more room for planting trees.
(Score: 2) by t-3 on Sunday November 20 2016, @09:03PM
Where are the laws of physics being denied?
(Score: 2) by dry on Monday November 21 2016, @03:02AM
Trees only grow when they have water and fertile soil. Places without trees usually are deficient in one or both of the requirements.
(Score: 2) by t-3 on Monday November 21 2016, @05:09AM
Not true. cacti grow well in the desert, and there are many tree-trees that can thrive in very dry and infertile conditions. Not to mention, landscaping and engineering can take care of water deficiencies. It's not like you go from a sand dune to an oak forest overnight, you have to work in succession just like nature. Plant cacti and other things that can survive easily at first, and baby what you need to. Manipulate the landscape to create systems that exploit all available water; even deserts have rain and there's always moisture in the air and underground. On top of this, modern infrastructure and technologies like desalination make importing water feasible. Organic matter can be imported as well, but in both cases, these just speed up the process, they aren't necessarily essential. If you're ever in AZ near the Saguaro National Park, stop by the office and ask them about the swales (or just look it up on google maps). These were put in place during the great depression to control floodwaters and never touched again, now they're densely vegetated and lush because the water that would normally rush away in a flash flood is slowed by the massive earthworks and soaks into the ground. Windbreaks, rock-wells, deep-planting, pit gardens, shade plants, terracing, etc. None of this stuff is new, it just hasn't been done on the massive scale I described above.
(Score: 2) by bzipitidoo on Sunday November 20 2016, @11:51AM
Could injecting CO2, rather than burying pure carbon, cause an imbalance of oxygen?
(Score: 1) by khallow on Sunday November 20 2016, @02:59PM
(Score: 2) by requerdanos on Sunday November 20 2016, @12:01PM
When I was a kid, I was taught in school that storing chemicals in the Earth mucked with nature and was called "pollution." And that pollution was bad.
(Score: 5, Insightful) by choose another one on Sunday November 20 2016, @12:40PM
Yeah, so we put them in the sky instead. Worked out really well that did.
When I was a kid the solution to industrial smog was to build taller chimneys, and in fact it worked. It caused acid rain thousands of miles away in another country, but hey can't have everything, and anyway that wasn't our problem...
(Score: 3, Informative) by maxwell demon on Sunday November 20 2016, @12:59PM
Carbon dioxide is unlike the usual pollution. It is a gas that naturally is in the atmosphere (you yourself are adding some with every breath). The problem is not that it is released at all (indeed, without any CO2 our planet would be doomed), but that we are adding more of it than is removed by natural processes (note that one of those natural processes is the formation of carbon minerals).
So you would have to argue that the increased formation of carbon minerals is a problem. However I have a hard time to imagine how that would be the case.
The Tao of math: The numbers you can count are not the real numbers.
(Score: 2) by requerdanos on Sunday November 20 2016, @01:12PM
Fair enough...
Are we planning to add more CO2 to the ground in the form of carbon minerals, than is removed by natural processes? :)
(Score: 2) by dry on Monday November 21 2016, @03:06AM
The natural process is for carbon to be sequestered as minerals. It rains, the water weathers silicates and you end up with carbon containing minerals.
Note that as the CO2 content of the atmosphere goes up, you get more rain which reduces the CO2 content, though it takes at least a 1000 years. This is just speeding up a natural process.
(Score: 2) by mcgrew on Sunday November 20 2016, @05:32PM
When I was a kid, I was taught in school that storing chemicals in the Earth mucked with nature and was called "pollution."
Not every chemical is a pollutant. The chemical H2o, for example. Carbonates are not pollution.
mcgrewbooks.com mcgrew.info nooze.org
(Score: 2) by requerdanos on Sunday November 20 2016, @06:51PM
No, H2O isn't a pollutant. But it does enjoy the position of being the most abundant greenhouse gas [nasa.gov] by a wide margin...
(Score: 0) by Anonymous Coward on Sunday November 20 2016, @08:56PM
So are you proposing we should try to reduce H2O evaporation rates instead?
(Score: 2) by dry on Monday November 21 2016, @03:09AM
It is also the greenhouse gas that self regulates the most, leaving us at a comfortable temp rather then the -30 that it would be without the H20 and other greenhouse gases.
(Score: 0) by Anonymous Coward on Sunday November 20 2016, @08:38PM
Your honor, plaintiffs have been observed dumping gallons of Dihydrogen Monoxide into soil on public school property on multiple occasions, yet they have the nerve to make accusations against my client, who is one of the largest employers in our state.
(Score: 2) by bradley13 on Sunday November 20 2016, @02:08PM
Let's assume that injecting CO2 into rock formations is a desireable goal. An honest question that I haven't seen answered anywhere: What is the energy requirement to extract CO2 from the atmosphere, liquify it, and inject it? Does this energy exceed the energy once gained by burning carbon to produce the CO2 in the first place?
I really don't know, but my intuition is that this is likely to have a negative energy balance, and much of that energy will come from carbon-based fuels...
Everyone is somebody else's weirdo.
(Score: 1) by khallow on Sunday November 20 2016, @03:07PM
Let's assume that injecting CO2 into rock formations is a desireable goal.
What has that rock formation ever done for us? It's just holding us back! Well, it and 6*10^24 kg just like it.
What is the energy requirement to extract CO2 from the atmosphere, liquify it, and inject it?
Rather low, if you just take it directly from the exhaust of a coal burning plant. And even if we extract CO2 directly from atmosphere, it's worth noting at low concentrations, a doubling of CO2 results in almost halving the energy cost of extracting that CO2 from atmosphere (assuming you're aiming for a moderately pure final concentration of the gas). So as the CO2 problem gets worse, the effort to remove it from atmosphere would get better.
(Score: 2) by linkdude64 on Sunday November 20 2016, @03:53PM
I imagine we would see increasing returns on conversion/extraction technology if it were opened to the free market and used by companies to offset pollution in response to tighter environmental regulations.
Rather than re-design your whole plant or throw away your perfectly good old machinery that just isn't efficient enough, bolt on a CO2 extractor and call it a day.
(Score: 0) by Anonymous Coward on Sunday November 20 2016, @05:21PM
It might be possible to do at an energy profit. The trick is to burn plants, which get their carbon from the atmosphere, in a biomass power plant, and run the concentrated CO2 from that plant through this process. The reason this works is that the reaction that locks the CO2 in the rock is slightly energetically favorable, it's just a question of bringing concentrated CO2, water, and rocks into the same place for long enough. The reason it doesn't happen fast enough for our needs in nature is probably a question of low concentration, and possibly the reaction results shielding the reactants from each other.
And to another questioner's question about getting the carbon back should we need it: that's actually really simple. Just heat up the rocks enough, and they'll release the bound CO2. It's the same process we use to turn limestone into concrete.
(Score: 1) by nethead on Sunday November 20 2016, @07:07PM
Does this energy exceed the energy once gained by burning carbon to produce the CO2 in the first place?
Since this was done on the Hanford Reservation I'm guessing the energy was nuclear.
How did my SN UID end up over 3 times my /. UID?
(Score: 0) by Anonymous Coward on Sunday November 20 2016, @03:14PM
if the plants (and algae) could vote, they'd massively vote 99% against this idea (unless they are suicidal).
Further more, plants and algae argue that they make oxygen for the guys that dig up energetic carbon and oxidized it
so we humans can stay alive and keep on giving them more carbon-dioxide.
burying carbon dioxide buries the carbon AND also the oxygen with it?
asshater says we will have to buy oxygen made from ocean water that used carbon-burying fossil fuels plants for power ...
(Score: 1) by fustakrakich on Sunday November 20 2016, @06:11PM
it's a drag being a rock [youtube.com]
La politica e i criminali sono la stessa cosa..
(Score: 0) by Anonymous Coward on Sunday November 20 2016, @10:21PM
Even little kids know that paper beats rock.
(Score: 2) by zeigerpuppy on Sunday November 20 2016, @10:50PM
The real story of carbon capture and storage is hundreds of millions spent on paying coal companies to run CC&S trials that have shown marginal viability at best. The main problem is that most power plants are nowhere near appropriate rock formations. The exception is places like Iceland where they are re-injecting carbonated water into geothermal deposits.
Carbon capture and storage is a distraction and uses up "green grants" to pay polluters to do nothing. It also vastly reduces energy return on coal (by about 30%), making it even less viable.
The solutions are very apparent: use solar and wind power; let the market mechanism operate properly without ongoing state subsidies to polluters and stop making up science to justify giving more money to coal companies.