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January 19, 2013 4:03 AM   Subscribe

How can we get CO2 out of the atmosphere? Get it out of the sea first. Making jet fuel from seawater is a pretty cool -- albeit energy intensive -- trick. But applying the same science to scrub CO2 out of seawater, where it is more densely concentrated than in the atmosphere -- and, by doing so, to reduce atmospheric levels of CO2 back to acceptable levels -- that's a game saver. "what would it take to draw atmospheric carbon down to 350 ppm with just this technology? . . . we would require the power of about 700 AP-1000 nuclear reactors. At the Chinese cost of $1.3b apiece and an 80 year lifetime this would cost a bit over $1 trillion dollars. That sounds like a lot of money. But its only about the cost of America’s 2003 Iraq War spread over the century, so I guess it’s a question of priorities."
posted by markkraft (68 comments total) 24 users marked this as a favorite

 
sadly, I'm guessing most ppl would prefer the CO2 over the nuclear reactors.

I've always wondered why no-one has proposed using the middle of the famously stable Australian interior for power stations. the water might be hard work (depending on where you put it) but its big, stable, and pretty safe from nimbys...
posted by sodium lights the horizon at 4:19 AM on January 19, 2013 [3 favorites]


We would require the power of about 700 AP-1000 nuclear reactors. At the Chinese cost of $1.3b apiece and an 80 year lifetime this would cost a bit over $1 trillion dollars.

He wouldn't happen to know where to find the uranium to fuel 700 more reactors for 80 years, would he?

We only have 500 so far (presently in operation plus those under construction, if my Googling is correct) and it's estimated that these reactors alone will already exhaust our planetwide supply of uranium within that time frame. We have less than 80 years to figure out how to switch to Thorium, or Fusion, or how to massively ramp up Solar capacity, or figure out how to actualize one of the various other magical technologies which propose to stretch out Uranium for thousands of years, in time for when Uranium-as-we-know-it starts to fail to meet our needs. His proposed project would advance that deadline considerably.

Maybe instead of using nuclear power, he supposes we build more plants that burn fossil fuel instead? In order to generate power for removing carbon from the environment?
posted by ceribus peribus at 4:39 AM on January 19, 2013 [6 favorites]


ceribus peribus: "We have less than 80 years to figure out how to switch to Thorium"

Depends on who you mean by "we", given the number of reactors already operating. Countries like India which have little uranium but huge thorium reserves are already facing this head-on. 80 years is really pessimistic.
posted by vanar sena at 4:49 AM on January 19, 2013 [3 favorites]


Don't get me wrong, I love the water based sequestration approach, and hope it's as effective as he claims it is. However, obtaining the quantity of energy he's proposing is more than a mere funding problem.
posted by ceribus peribus at 4:49 AM on January 19, 2013 [4 favorites]


"We only have 500 so far (presently in operation plus those under construction, if my Googling is correct) and it's estimated that these reactors alone will already exhaust our planetwide supply of uranium within that time frame."

Obviously, nuclear becomes more sustainable with fast breeder reactors and/or with Thorium-powered reactors.

However, you do not need a solution from the outset that is entirely sustainable... nor do you need one that is entirely nuclear. There are several countries bordering our oceans, such as Iceland, Norway, etc. that have significant excesses of clean energy, left untapped.
posted by markkraft at 4:54 AM on January 19, 2013


That's a huge relief, vanar sena -- I was under the impression that all thorium facilities had been shut down and/or were only operating on an experimental scale.
posted by ceribus peribus at 4:57 AM on January 19, 2013


One point twenty-one gigawatts!?!?!

I have a two-fold question:
a) If the extracted carbon is turning into hydrocarbon fuels, aren't you just cycling the carbon back into the atmosphere as soon as the fuel is used?

b) If so, what is the rate of uptake of carbon into seawater from the atmosphere? If it's taken up at a rate any slower than we're putting it back into the atmostphere, we've actually found ourselves worse off than before...
posted by kaibutsu at 5:05 AM on January 19, 2013 [1 favorite]


ceribus peribus: " I was under the impression that all thorium facilities had been shut down and/or were only operating on an experimental scale."

No, you're perfectly correct - the existing reactors are all old designs and are not practical in scale. The likely (perhaps overly optimistic?) timeframe to make a dent in India's current use of coal-fed thermal energy is around 15-20 years. That's still quite a bit less than 80 years though.
posted by vanar sena at 5:24 AM on January 19, 2013 [1 favorite]


"If the extracted carbon is turning into hydrocarbon fuels, aren't you just cycling the carbon back into the atmosphere as soon as the fuel is used?"

The two processes, fuel production and carbon sequestration, rely on the same extraction technology, but if used for carbon sequestration, you would create pure CO2, which can then be stored in spent oil and gas wells, etc.

There is, however, an interesting way of using that CO2 to produce fuel, which also relies upon the oceans for its implementation. It would be pretty convenient to combine these systems together, I suspect.
posted by markkraft at 5:40 AM on January 19, 2013 [2 favorites]


So we need energy, but it doesn't have to run 24/7 predictably, and it could be used to produce high energy containing fuels that would be nifty for transport as oil depletion (sorry, US fracking fixed that, right?).
How about solar?
Or does it have to be nuclear to gather enthusiasm?
posted by bystander at 6:20 AM on January 19, 2013 [3 favorites]


sadly, I'm guessing most ppl would prefer the CO2 over the nuclear reactors.

I've always wondered why no-one has proposed using the middle of the famously stable Australian interior for power stations. the water might be hard work (depending on where you put it) but its big, stable, and pretty safe from nimbys...


It's an obvious solution to this expat, but Australians view nuclear power like the panicked bystander in a Godzilla movie so good luck convincing them. And I'm obviously ignoring the unique Speckled Sand Lizard and the Sacred Rock.
posted by Charlemagne In Sweatpants at 6:41 AM on January 19, 2013 [1 favorite]


That's still quite a bit less than 80 years though.

Well, depending on which estimate turns out to be correct, we might not even have 80 years.

If you'll forgive me quoting myself from last summer:
Reports estimating uranium depletion vary wildly, to say the least. One of the more pessimistic ones was a study released by the European Commission in 2001, saying that the current level of consumption would exhaust all primary uranium sources within 42 years (72 years if secondary and military sources of uranium were included). However, those estimates assume that nuclear reactors continue to supply the same percentage of global energy as they do today -- replacing fossil fuel plants with nuclear plants would require a six fold increase in uranium consumption, reducing the global supply to only 12 years.

Other studies in the "pessimistic" category predict supplies of 70, 100, and 130 years, depending on the viability of secondary uranium sources and whether any attempt is made to displace oil and coal during that time.
However, I didn't mean to derail this thread into a resource depletion discussion.

We desperately need a viable means for massive scale carbon sequestration, since we've far overshot the point where cutting our emissions to zero would have been enough to avert climate change entirely. According to a World Bank report released in November, the world only has about five years to implement the necessary changes required to avert "the most severe impacts" of what could possibly be a 4C or greater warming by the year 21001 based on present conditions.

The biggest concern with the project Morgan describes is that it's questionable whether we have the planetwide resources to build and operate enough power plants to meet the energy needs, which is ironic since pollution from fossil fuel power stations are what created the problem in the first place. We could partially implement it and at least get some benefits, sure. I'm really hoping that it will serve as a basis for research that discovers a more efficient/lower power approach though, and soon.

1 Hey, that's just over 80 years away! Bonus: the report also says that if governments don't meet their current promises to fight climate change, the planet could reach the 4C increase by as early as 2060.
posted by ceribus peribus at 6:47 AM on January 19, 2013


The ocean contains something like 97-98% of the biosphere's CO2, and is only absorbing something like a third of the new CO2 we're adding to the atmosphere. Henry's Law suggests that this has to be a non-equilibrium effect, which would mean the oceans can't absorb more CO2 from current atmospheric levels nearly as fast as we're emitting it, which would mean that extracting CO2 from the ocean might be useful for restoring ocean pH but not for restoring atmospheric CO2 levels. Am I missing something?
posted by roystgnr at 6:49 AM on January 19, 2013 [3 favorites]


so I guess it’s a question of priorities.

And ours are all wrong. It's going to have to be a fix that requires multiple approaches, not a magic bullet (since there are no magic bullets). We need to reduce our CO2 emissions by reducing our demand on fossil fuels and transition to less damaging energy sources. We also need to improve our CO2 scrubbing and sequestration ability, while fighting all the other consequences of climate change.

But if we're trusting in the government and companies to select the correct priorities then we're in for a long wait.
posted by arcticseal at 6:57 AM on January 19, 2013 [5 favorites]


> I've always wondered why no-one has proposed using the middle of the famously stable Australian interior for power stations. the water might be hard work (depending on where you put it) but its big, stable, and pretty safe from nimbys...

It's an election loser. It's been proposed, just not out loud (and never in a federal election year). It stands as a Liberal Party Proposition, No. 24 (on Nuclear Industry):
The Federal Council believes that Australia should expand its current nuclear industry to incorporate the entire uranium fuel cycle, the expansion of uranium mining to be combined with nuclear power generation and worldwide nuclear waste storage in the geotechnical stable and remote areas that Australia has to offer.”

Proposition 23 (on Nuclear Power) reads:
That Federal Council believes that nuclear power is the most significant component of an immediate response to climate change and calls on the Australian Government to introduce a technical and regulatory scheme, including appropriate environmental and operation safeguards, and any other measures necessary for the development and provision of nuclear power on a market driven basis.
I think you'll find nimbyism is alive and well when it comes to Australia's beautiful outback -- which belongs more to Australia's first people than any new Australian could ever dare lay honest claim to, so much so Proposition 24 won't rate a mention in this year's federal election campaigning (unless some 'nimbys' shine some light its way).

Political suicide.
posted by de at 7:02 AM on January 19, 2013 [1 favorite]


ceribus peribus : He wouldn't happen to know where to find the uranium to fuel 700 more reactors for 80 years, would he?

"Spent" fuel in most reactors still contains approximately 95% of its original U235, as well as containing a host of much "hotter" isotopes that work just fine in a reactor. We have far, far more than enough fuel to power the world's reactors - And a few thousand more - For centuries, if we stop looking for a place to bury our waste in the desert, and start recycling the damned stuff.

Jimmy Carter really screwed the pooch (and the whole country) on this one. He effectively managed to create an artificial scarcity of the most practical* form of clean energy available to us, and in the middle of an energy crisis at that. Mighty fine presidentin' work there, Lou!

* Yes, I love solar. I love wind. I love tidal hydro. And although we need to expand all of those as rapidly as we possibly can, they just won't realistically suffice to meet the world's energy needs on their own.
posted by pla at 7:43 AM on January 19, 2013 [6 favorites]


We're all going to boil in the waste heat of our exponentially increasing demand for energy in a couple hundred years anyway. Either that or we drown in horseshit - I forget which it is
posted by JustAsItSounds at 7:43 AM on January 19, 2013


"How about solar? Or does it have to be nuclear to gather enthusiasm?"

The author involved no doubt suggested nuclear as it potentially delivers the most bang for the buck of the various green energy sources.

Sure you can use solar... but it will cost you considerably more than a trillion dollars to pull it off. That, incidentally, is why I suggested Iceland's vast geothermal and Norway's hydro green energy sources as excellent alternatives to nuclear.
posted by markkraft at 7:50 AM on January 19, 2013 [2 favorites]


This assumes that we can permanently sequest massive amounts of CO2, which is far from proven.
posted by Dasein at 8:00 AM on January 19, 2013


[A few comments deleted; there is no reason to lob accusations at other people.]
posted by LobsterMitten at 8:01 AM on January 19, 2013


sodium lights the horizon: why no-one has proposed using the middle of the famously stable Australian interior for power stations.
Transmission losses, just to the coast of that continent, would be enormous. Unfeasible.
posted by IAmBroom at 8:23 AM on January 19, 2013 [1 favorite]


markkraft: However, you do not need a solution from the outset that is entirely sustainable... nor do you need one that is entirely nuclear. There are several countries bordering our oceans, such as Iceland, Norway, etc. that have significant excesses of clean energy, left untapped.
An excess of energy for Iceland != 1.21 GW. Let's get data:

Total electricity consumption in Iceland was 9,925 GWh in 2006. That's 1.1 GW average usage. And all of it comes from renewable sources (same source).

OK, to my surprise... Iceland seems to have the power to pull this off.
posted by IAmBroom at 8:35 AM on January 19, 2013


Ocean acidification is already becoming a problem; perhaps there's a better place to stash our excess CO2 than in the sea?
posted by anadem at 8:35 AM on January 19, 2013 [6 favorites]


It seems to me that this post has multiple things that are trying to be accomplished at once:
1. Extraction and sequestration of CO2 from seawater;
2. Extraction of CO2 from the atmosphere as a byproduct of the sequestration of CO2 from the sea;
3. Production of carbon based fuel using the carbon from CO2;
4. To facilitate these goals, adoption of nuclear energy.

Very ambitious. Maybe too ambitious.

Breaking down what he says:

1. CO2 can be extracted from seawater can be done using a specialized filter system and the value of it is that CO2 is 140 times more concentrated in the sea than it is in the air. The sequestration then occurs in wells drilled at sea although later he cites the cost of the Navy's "ocean-going platform" as being a reason to put the project on land which then begs the question of sequestering the CO2 beneath the ocean. Putting that aside (let's assume we sequester the CO2 on land or under the continental shelf), the process requires a lot of energy in order to produce the H+ ions from electrolysis that are needed for the process or removing CO2 from seawater.

2. He makes the assertion that "There is substantial equilibration between ocean and air on a timeframe short enough to be relevant to climate." but provides no numbers on the timescale for the transfer of CO2 from the atmosphere to the ocean and whether enough CO2 can be removed to make a difference. He simply says "Does it matter whether CO2 is captured from the ocean or from the atmosphere? I’ve assumed not, so long as CO2 is removed from the biosphere. Atmospheric CO2 causes global warming, oceanic CO2 causes ocean acidification. Both have serious consequences." True, but will this accelerate ocean acidification? Will it effectively remove CO2 from the atmosphere? He simply says removing CO2 from the biosphere is good. I believe this is in general true, but more details on time, quantification of effects and possible side effects need to be examined.

3. The production of synthetic fuel puzzled me initially. It's obvious why the Navy wants to do this, even if it is not cost effective. But why would he propose its production as part of a sequestration effort? He initially states that "Liquid hydrocarbons account for about one third of fossil carbon dioxide emissions, and ...it is simply not feasible to substitute for liquid fuel in most long haul transport, aviation, or agricultural and industrial prime movers." Others have challenged this assertion, but let's take the statement at face value. Why would he want to take this up in this context? There are two or three possible reasons, all of which are discussed or hinted at: 1. Hydrocarbon extraction from the earth requires energy and releases CO2 as a byproduct of the extraction process independent of the energy use. (Ever seen the flare off of dangerous hydrocarbons at a well? What about methane leakage from extraction, including fracking?); 2. Most extracted hydrocarbons have nasty polluting impurities like sulfur, etc (c.f., Beijing pollution this week; 3. Refining extracted hydrocarbons is extremely energy intensive.

These are interesting points, but as far as I can tell, there is no quantification of the purity of the synthfuel, nor a clear separation of energy costs vs. cost of refining. He implies both are better, but there are no figures that I cans see for this part of the effort.

4. To make all this work, he needs a pretty significant power source and he proposes nuclear power as being necessary to prevent more CO2 emissions that would tip the scheme over the edge into CO2 polluting rather than removing. Given this, the question about energy cost to produce synthfuel is rather relevant as if it is more expensive to produce synthfuel than to extract and refine hydrocarbons, then why not just use nuclear power to generate the power to refine extracted hydrocarbons? I'm guessing synthfuel is not more power intenstive, but without numbers it's just a guess.

Summing up, this is an interesting combination of ideas, but I'd like to get answer to questions such as: How much energy does it take to sequester the CO2 without also making synthfuel? Why not just focus on a system that sequesters CO2? Is the ratio of CO2 extracted from the air after removing CO2 from seawater equal to the amount sequestered? If not, what is the ratio? Does it just de-acidify the oceans, or does it remove CO2 from the air but not appreciably change the acidity of the oceans or both? What is the energy cost to make synthfuel from seawater compared to the cost to extract it and refine it from extraction hydrocarbons? Are there any pollutant side effects from synthfuels?
posted by BillW at 8:38 AM on January 19, 2013 [1 favorite]


Where exactly are they intending to put all the CO2? Is it really feasible to store it by pumping it into empty natural gas chambers?

I think you coudl probably find the power to extract the CO2 but I just don't understand how its possible to store it away somewhere that it won't be able to escape eventually. Seriously how can you hide away millions of tons of any gas?
posted by mary8nne at 8:39 AM on January 19, 2013


we would require the power of about 700 AP-1000 nuclear reactors. At the Chinese cost of $1.3b apiece
From Wikipedia:

In 2007, the reported cost for the first two AP1000 units under construction in China was $5.3 billion.

In 2009, the published cost for 4 AP1000 reactors under construction in China was a total of $8 billion.

In 2010, the Chinese nuclear commission expect construction costs would fall significantly once full scale mass production is underway. In addition, a domestic CAP1400 design based on the AP1000 is due to start construction in April 2013 with a scheduled start of 2017. Once the CAP1400 design has been proven, work is scheduled for a CAP1700 design with a target construction cost of $1000/kW

Clearly there is a difference between aiming for $1000/kW and actually getting there. It is worth noting that using this nuclear plant in the US or western Europe is going to cost more than one built in China, probably a lot more, and it seems likely that this cost does not include the cost of decommissioning the plant, which is substantial. Costs for some plants has reached $4000/kW but is always into the $100s of millions. This would clearly impact the economics of the project proposed here.

The other issues is this 'gives a carbon capture cost of about $114 per tonne CO2'. This figure is way above the marginal abatement cost of carbon from nuclear, so unless you ave already decarbonised the energy system it would make more sense to use any nuclear capacity built to displace emissions from coal and gas power stations. Additionally, this would likely save more CO2 per plany anyway since there would bit be any efficiency losses from the scrubbing you get the saving purely from swtiching off the coal station.
posted by biffa at 8:42 AM on January 19, 2013 [2 favorites]


mayr8nne/anadem, the proposal is to sequester it beneath the seabed, not in the ocean. Since the natural gas had to be extracted artificially, presumably putting another gas into the ground and then sealing the hole would keep it there, though as others have mentioned, the effectiveness of sequestration is an open debate. That said, sequestering it under ti ocean has the advantage that the ocean exerts a lot of pressure to keep the gas from escaping or, it does escape, reducing the amount or preventing it from rising to the surface.
posted by BillW at 8:46 AM on January 19, 2013


Is Carbon Sequestration actually taken seriously though? It has always sounded like an absurdity to me.

Looking at the methods described on: http://en.wikipedia.org/wiki/Carbon_sequestration It just doesn't seem like a realistic solution for the size of the problem.

It would be like saying - "After we burn all this Coal, Oil and Gas, we collect EVERY little bit of CO2 and put that back in the hole it came from." All of it. Back into each of the little holes they came out of and then we seal those up somehow so it can't escape.

We already inject a lot of CO2 into natural oil and Gas "reservoirs" (ie the holes in the ground that he Oil and Gas was in) but we do this to help get more of the Oil and Gas out. It just seems doubtful that you could continue putting loads of CO2 in there after thats finished.

What about earthquakes, leakage etc? There are already pockets of CO2 in the earths crust that occasionally leak out again.

What about these BioChar things? Wikipedia claims they actually produce more energy? Seems a bit perpetual motion machine to me.
posted by mary8nne at 9:03 AM on January 19, 2013


The nuclear thing is a needless distraction. Unlike most uses of our electric grid, this kind of operation can run whenever there is power coming in. So it's a perfect fit for solar/tidal/wind.

Build an excess of wind turbines. Use the excess to suck CO2 out of the oceans.

Done.
posted by ocschwar at 9:07 AM on January 19, 2013


Either that or we drown in horseshit - I forget which it is

This could solve the topsoil loss issue. Rotting human flesh combined with horseshit will make excellent compost.
posted by srboisvert at 9:15 AM on January 19, 2013 [1 favorite]


ocschwar, power density. It takes *a lot* of energy to produce hydrogen by electrolysis - hydrogen and oxygen like binding together. To produce enough power using wind turbines to produce the H necessary for this, well, you do want to be able to see the ocean from the shore again, don't you? ;-)

Geothermal is an interesting idea where it is already in the power grid, but that is a fairly limited portion of the world...
posted by BillW at 9:18 AM on January 19, 2013


thorium also has the potential to make use of exisiting spent nuclear waste that must otherwise be stockpiled:

Is Thorium A Magic Bullet For Our Energy Problems?:

MARTIN: However - you're welcome. However, some of those conclusions are just wrong. So when we talk about the waste, one of the things that skeptics of the liquid fuel thorium reactor ignore is the fact that because the core is a liquid, you can continually process waste, even from existing conventional reactors into forms that are much smaller in terms of volume, and the radioactivity drops off much, much quicker. We're talking about a few hundred years as opposed to tens of thousands of years.

So to say that thorium reactors, like any other reactor, will create waste that needs to be handled and stored, et cetera, is true, but the volume, we're talking tenths of a percent of the comparable volume from a conventional reactor. And not only that, but we've got all that waste from our existing nuclear reactor fleet, just sitting around, and we've got no plan for it.

And so we're talking about building a reactor that can process that into forms that are much, much easier to deal with. And so that's the waste issue.

But I also want to take just a step back, here, if I may for a moment, and talk about this whole issue of risk. We've been focusing in on some details of protactinium and the build-up of U-232 and so on, but my question to Dr. Makhijani would be: OK, you have concerns about thorium-based nuclear power, and those are not to be dismissed lightly. But what is the answer if this is not it?

Because as I demonstrate in "SuperFuel," the book, renewables are not going to solve our problem in the time scales that we need it - in other words, in the next 30 to 50 years. Solar and wind and so on are just not going to be at large enough scales and at the prices to really replace a significant fraction of fossil fuel-based energy in the timeframes that we need.

So we're talking about two different risks, here: the risks associated with an innovative form of nuclear power based on a very abundant and safe material versus the risk of a three-degree-Celsius, let's say, rise in global temperatures over the next 50 years, within, you know, my son's lifetime. So, as a society, I don't think we're very good at calculating risk. And so to hone in on these pretty technical issues of, well, there might be some proliferation risk with thorium, there's no question that thorium - liquid-fueled thorium reactors can be used to consume the existing waste from conventional reactors.


New Age Nuclear:
BY THE END OF this century, the average surface temperature across the globe will have risen by at least 1.4˚C, and perhaps as much as 5.8˚C, according to the United Nations Intergovernmental Panel on Climate Change.

That may not sound like much, but small changes in the global average can mask more dramatic localised disruptions in climate. Some changes will be global: we can expect sea levels to rise by as much as 0.9 metres, effectively rendering a huge proportion of what is now fertile coastal land uninhabitable, flooding low-lying cities and wiping out a swathe of shallow islands worldwide.
The principal culprit is carbon dioxide, a gas that even in quite small quantities can have a dramatic impact on climate, and has historically been present in the Earth's atmosphere at relatively low concentrations. That was until human activity, including burning fossil fuels, began raising background levels substantially. Yet while we're bracing ourselves to deal with climate change, we also face soaring demand for more energy - which means burning more fossil fuels and generating more greenhouse gases.


so what's the point of removing all that CO2 if we just continue to generate more? there needs to be a wholesale move AWAY from burning carbon as our primary energy source. and Thorium, right now, is the only real viable way to accomplish that. electric transportation on a massive scale becomes a possible reality.

nuclear power generation is absolutely relevant in this discussion.
posted by ninjew at 9:28 AM on January 19, 2013 [1 favorite]


The nuclear thing is a needless distraction. Unlike most uses of our electric grid, this kind of operation can run whenever there is power coming in. So it's a perfect fit for solar/tidal/wind.

mmmm, maybe. The process may not lend itself to start/stop operations. there are lots (most) of industrial chemical processess that require a set temperature range and process speed for effeciency and sometimes to just work, so it is not clear that the on/off/variable range of most renewables would lend itself to the process.

OTEC (ocean thermal energy conversion) might work, nuclear will work, it seems solar would be a great fit in the tropics for this and wind could be since it is usually dependable on certain coastline to a pretty great degree.

And using CO2 from the oceans to make synthfuel seems a great way to still have the plusses of liquid fuel (ease of transport, energy density, storage safety) without the minuses (enviroment damage from extraction, aquifer contimination, cost of refining, so on). The carbon used would be neutral to the biosphere since that is where it is coming from, the biosphere.
posted by bartonlong at 9:52 AM on January 19, 2013


With that much power, we can just separate it straight from the air and not have to pull it through the ocean. Just give me 700 nuclear reactors, and a place to stand on, and I can move the Earth.
posted by Made of Star Stuff at 10:02 AM on January 19, 2013


And thorium is not the only viable way to reduce our CO2 output. Robert Socolow proposed 15 possible strategies that we could ramp up over the next 50 years to reduce our carbon output. We only need to use 9 of them in order to stop increasing our carbon output. A mixed strategy is doable, and some strategies are already ramping up, though not fast enough. I love thorium reactors as much as the next girl, but let's not pretend that we're going to solve everything with only thorium.
posted by Made of Star Stuff at 10:08 AM on January 19, 2013 [1 favorite]


That we are even talking of such a boondoggle is mind boggling conflagration.

See also carbon cycle chart and oceanic carbon cycle.
posted by stbalbach at 10:38 AM on January 19, 2013 [2 favorites]


Given that people are still thinking in terms of cost benefit when it comes to carbon capture, I wonder how many other scientists (of all stripes) have stopped bothering to come up with miracle solutions and are instead looking at home to make life livable and +3C or more...
posted by Slackermagee at 10:58 AM on January 19, 2013


The main article in the OP seems more focused on extracting dissolved carbon to make liquid fuel, which, as its title suggests ("A Zero Emissions Vehicle Fuel?"), would be carbon-neutral at best, since we'd be taking it from the ocean but putting it right back into the air.

The pullquote in the OP, speculating that we could use this technology to get atmospheric CO2 back to 350 ppm with the equivalent of 700 nuclear reactors, is based on extracting 4 Gt of CO2 from the ocean every year for 100 years. Leaving aside the question of where to put it, I was curious how much water that would involve.

4 Gt CO2 = 4 billion metric tons = 4e15 grams CO2 extracted per year. The total concentration of dissolved inorganic carbon (DIC) in the ocean today, which includes all the equilibrium forms of CO2 in water (CO2, H2CO3, HCO3-, and CO3-2), is about 0.0021 mol/kg seawater, or 2.1 mol per cubic meter. One g-mol of CO2 weighs 44 grams, so that's about 92 grams of CO2 per cubic meter of seawater.

Extracting 4e15 grams CO2 per year would require 4.3e13 cubic meters of seawater, which is about 1.1e16 US gallons. Divided by a world population of say 6 billion people, that would be about 7,200 cubic meters, or about 1,800,000 gallons, per person, per year. Roughly 20 tons of seawater, per person, per day. For 100 years. By comparison, the annual flow of the Amazon River is about 6.6e12 cubic meters, so this proposal would mean processing over six Amazon's worth of water every year, more than all the world's rivers combined. That's a lot of water.
posted by Dixon Ticonderoga at 11:04 AM on January 19, 2013 [5 favorites]


Why isn't it easier to extract the CO2 at the smokestacks of the coal plants?

You got your electricity, you got your heat, you got your concentrated pinpoint source of the stuff you want to sequester.

Letting it go into the air, then into the ocean, then trying to extract it seems -- irresponsible.
posted by hank at 11:11 AM on January 19, 2013 [2 favorites]


we would require the power of about 700 ... nuclear reactors.

So, then, it's the power that's needed, not the 700 nuclear reactors (and the waste and the centuries of security and etc.). So this could be done with offshore wind turbines. Or tidal or wave generators. Etc.
posted by Twang at 11:13 AM on January 19, 2013


Why isn't it easier to extract the CO2 at the smokestacks of the coal plants?

You got your electricity, you got your heat, you got your concentrated pinpoint source of the stuff you want to sequester.


You know what's even easier than that? Building a nuclear reactor (thorium, uranium, fast breeder, whatever) on the other side of the coal power plant and using that heat source to turn the generator. And storing nuclear waste is considerably easier (technically, not politically) than sequestering carbon in a geological time scale meaningful way.

So yea, putting all this money into carbon sequestration then continuing to burn coal, when we have much cleaner sources of power available? just crazy, crazy on stilts even. No matter how you feel about the climate change debate, spending money to dig something up, burn it, than rebury it cause the burning is hurting you worse than just leaving it buried? HOLY SHIT, THATS CRAZY.

And for the 80 years of fuel, if we are processing that much water surely we can spare some of the gigawatts to filter the uranium out of seawater(I remember reading there is quite a bit of dissolved uranium in seawater, and hey, lots of dissolved potassium and phosphorous that could fertilize crops) and use THAT for fuel? if we need to use nuclear at all...
posted by bartonlong at 11:28 AM on January 19, 2013


The only thing I have to offer here:

1. Oceanic CO2
2. ????
3. Carbon fibre bicycle frames
4. Profit!

Geothermal???
posted by jimmythefish at 11:30 AM on January 19, 2013 [1 favorite]


Why isn't it easier to extract the CO2 at the smokestacks of the coal plants?

CO2 is super-concentrated at the smokestack-- roughly 10% by volume, or 100,000 ppm, so 250 times the atmospheric concentration. Even at the source, it's still a very large volume of gas to scrub, meaning a large extraction plant, plus then having a very large volume of collected CO2 that needs to go somewhere. Power plants are built near the end-users and usually aren't anywhere near a suitable underground formation, so large-scale sequestration would probably mean long pipelines carrying pressurized CO2. Frankly, that thought terrifies me far more than n oil or gas pipeline. I've always thought sequestration of CO2 in gas form is just a crazy idea.
posted by Dixon Ticonderoga at 11:32 AM on January 19, 2013 [1 favorite]


What's the waste heat generated by 1000 nuclear reactors?
posted by weston at 11:33 AM on January 19, 2013


OK, to my surprise... Iceland seems to have the power to pull this off.

This is a common units mistake. Using that wiki page Iceland uses about 10,000 GWh and has an installed capacity of 1707 MWe *24hrs/day*365days about 15,000 GWh with some downtime etc. Each of those 700 AP1000 is 1117 MWe. So Iceland's entire current capacity gets you at best about .2% of the total.
posted by a robot made out of meat at 11:44 AM on January 19, 2013


Also, also. The statistic about CO2 being 140 times more concentrated in seawater is only true in the sense that seawater is about 1,000 times denser than air. A cubic meter of seawater contains about 92 grams of CO2 while the same volume of air contains about 0.7 grams.

But if you take equal masses of seawater and air, CO2 is way more concentrated in air. That cubic meter of water, containing 92 grams of CO2, has a mass of about 1,000 kg. But the same mass of air contains about 600 grams of CO2. This makes it less clear to me that extraction from water has an advantage.
posted by Dixon Ticonderoga at 11:49 AM on January 19, 2013 [4 favorites]


Can we just plant a large variety and number of trees? We probably have the space and time to nurse them, the lightweight trucks to transport them, and the land to let them take root...

I'm particularly tempted to say why not plant them within relative close proximity of major CO2 producers. Say a 5-10 mile radius.
posted by JoeXIII007 at 12:01 PM on January 19, 2013


Charlemagne In Sweatpants: "And I'm obviously ignoring the unique Speckled Sand Lizard and the Sacred Rock"

Actually, since the Aborigines don't want people climbing or generally fucking around on/close to Uluru, making the area dangerously radioactive might solve several problems.
posted by Joakim Ziegler at 12:15 PM on January 19, 2013


Carbon-neutral fuel generation is a fantastic idea. It wouldn't reverse global warming, but assuming wide-scale adoption, it could slow or even stop the process. Is it as good as carbon-negative energy? Of course not. But it's far more realistic.

Assuming his numbers are correct (which I kind of doubt), $6.75/gallon is a completely workable cost. Oil-derived gasoline will almost certainly be as expensive within 15-20 years, so it seems likely that it will eventually become a cost-effective alternative, even in the absence of government intervention.

If solar or wind power is used to drive the conversion, even better. There are tons of environmental costs associated with coal burning, mining, fracking, and so forth, that could be eliminated by switching to a system based purely on liquid fuel extracted from sea water.
posted by dephlogisticated at 1:31 PM on January 19, 2013


Build an excess of wind turbines. Use the excess to suck CO2 out of the oceans.

Why not use electrification to help coral build coral reefs?

In fact, such a use could be "dump loads" for said turbines. And designs like Doug Selam's floating turbines would be rather cheap to install and perhaps service.
posted by rough ashlar at 1:40 PM on January 19, 2013


That we are even talking of such a boondoggle is mind boggling conflagration.

Nuke plants and their supporters are looking for an excuse to build the nuke plants. This conversation gives 'em that excuse.

Its like the "lets build space power and beam it down with Microwaves" people are looking for an excuse to put rockets into space and build a space elevator.

And unless I say "why not use LESS to begin with" or "perhaps you'll should be trying to figure out how to live in an energy budget of what you can harvest and use via sunlight and wind VS demanding a 24x7 all you can eat buffet" - odds are no one is going to express such on Technofix Pespi Blue. Because people who use a technological medium like technological solutions such as 'a tablespoon of Uranium gets you all the power you need for a year'.
posted by rough ashlar at 1:51 PM on January 19, 2013


And unless I say "why not use LESS to begin with"

You can say whatever you want to say, but it's worth considering what people will actually *do*. A lot of the increase in future carbon emissions will come from the developing world, who are pretty much guaranteed not to listen to westerners on the internet telling them to use less energy.

Developing a technological replacement for fossils fuels is the only option we have. The culture war is already lost. People have been pounding their fists down demanding sustainability for decades while our actual "progress" has been perfecting new technologies for strip-mining and fracking and removing mountaintops and drilling in mile-deep ocean and the melting arctic slush to extract every barely-useable atom of carbon from the earth's crust, turn it into a liquid, and put it in an SUV.
posted by crayz at 2:09 PM on January 19, 2013 [3 favorites]


2. ???
3. Carbon fibre bicycle frames
4. Profit!


With just a bit more pressure compress the carbon into a much more compact form and then fund the program with "saved the world" diamonds!
posted by sammyo at 2:19 PM on January 19, 2013


Nuke plants and their supporters are looking for an excuse to build the nuke plants. This conversation gives 'em that excuse.

Guilty as charged. Australia's fear of nuclear power is such a backward Luddite response that it makes me angry every time it's brought up. They're 50 years in the past!
posted by Charlemagne In Sweatpants at 2:46 PM on January 19, 2013 [1 favorite]


Assuming his numbers are correct (which I kind of doubt), $6.75/gallon is a completely workable cost. Oil-derived gasoline will almost certainly be as expensive within 15-20 years

Light Sweet Crude Oil (WTI) Futures: Dec 2021: 84.24 (still in backwardation)

IEA predictions have oil at between $120 and $140 in 2035.

If you couple this with increased fuel efficiency and electric automobile usage in 15-20 years, and the fact that the US is expected to be an oil exporter by that time, it doesn't seem obvious to me that gasoline prices will double in the US in 15-20 yrs (in today's dollars) without an oil/gasoline tax increase or other intervention.

I like the idea of having international trade agreements include a "carbon tax" of some sort. Use the tax revenue to fund alternative energy projects. With the latest horrific global warming projections, it seems there should be a global outcry demanding this sort of thing. The tax could be adjusted on a per country basis dependent on current cost of living and state of "development" or something and adjusted depending on global economic conditions (increase the tax during boom times and decrease during recessions). Leading energy companies and industrial and academic experts could be part of a panel that decides how to invest the tax revenue. Obama needs to try to do something real to address this in the next four years, or it should be considered a significant failure on his part.
posted by Golden Eternity at 3:24 PM on January 19, 2013


In the spirit of Brand New Day, CiS, I feel it necessary to point out that you're starting to become tiresome again…
posted by Pinback at 3:24 PM on January 19, 2013 [1 favorite]


Australia's fear of nuclear power is such a backward Luddite response that it makes me angry every time it's brought up. They're 50 years in the past! is shared by almost everyone, all over the world.

I agree that the health costs of coal are widely ignored, and under-rated, and that nuclear is a lot "cleaner" on that score, but to act like opposition to nuclear is a uniquely antipodean response is ridiculous, and it is a source of constant amusement to me, how many nuclear boosters can only refer to the success and costs of plants on paper, as all of the, you know, actually-built plants cost literally billions of dollars more to run and build than expected and outputs are typically lower too.

Nuclear as its pros and cons, a panacea it's not. Mocking aboriginal cultural heritage and efforts to preserve endangered species and biodiversity is both anthropocentric, and racist. Aboriginals own a tiny proportion of the land in central Australia, and you want to fucking take that away from them, too. Lovely.
posted by smoke at 3:57 PM on January 19, 2013 [4 favorites]


But in the rest of the world it's a minority position held by hippies and MeFites. Countries still build nuclear plants. In Australia is a mainstream government position, which is a huge red flag that the hippies have power.
posted by Charlemagne In Sweatpants at 4:07 PM on January 19, 2013


Charlemagne In Sweatpants : Mocking aboriginal cultural heritage and efforts to preserve endangered species and biodiversity is both anthropocentric, and racist.

Sorry, but poking fun at primitive superstitions crosses mere lines of "race". Not racist, but rather, realistic.

They don't want people to climb... their magic... rock? Seriously guys? Stewards of the planet, protectors of the outback, preservers of a lost culture, and your big peeve involves thwarting a stereotypical geek sport?


The problem here doesn't significantly differ between nuclear power and protecting sacred rocks - We have exactly two choices - Improve our futures by embracing science, or go back to the energy needs of a pre-industrial-revolution planet. The "compromise" of burning coal like a magic heat-producing rock has brought the planet to the brink of environmental collapse.
posted by pla at 4:31 PM on January 19, 2013


But in the rest of the world it's a minority position held by hippies and MeFites.

This is total nonsense that you clearly made up on a subject you have strong opinions about but know little of. cite:

Are you in favour or opposed to nuclear power in your country?

Only 20% of people overall were clearly in favour of nuclear with 36% having balanced views and 37% clearly opposed....

The risks of nuclear power as an energy source outwiegh its benefits to just 53% of respondents....

...Only 51% think their country's national nuclear safety authority is capable of ensuring safe nuclear operation....

Half of Europe's citizens think radioactive waste cannot be desposed of safely...


That's Europe, and across the world:

59% of respondents do not favour new nuclear power plants being built.

Yeah, it's such a freaking edgy, out-there position that only crazy people who are crazy would hold. Sigh.

They don't want people to climb... their magic... rock? Seriously guys? Stewards of the planet, protectors of the outback, preservers of a lost culture, and your big peeve involves thwarting a stereotypical geek sport?

And you have the temerity to call them ignorant. You clearly know nothing about Aboriginals, Australia, Uluru, or Native Title and possibly many other things.
posted by smoke at 5:35 PM on January 19, 2013 [6 favorites]


I'm not sure why the spiritual beliefs of this one group are nonsense. Can I irradiate the wailing wall, or bury waste at Arlington? Why are those places allowed to have 'magic' properties?
But this is beside the point.
The article cites a US Navy study where nuclear was suggested as a power source to produce synfuel, because the US Navy has mobile, floating nuclear reactors, so it is a useful source of energy for them.
The optimistic figure of $1000/kW for nuclear power was cited above, a figure that solar power (for example) has already bettered, with no ongoing fuel costs, better reliability and no catastrophic failure mode.
Please explain why nuclear is needed or desirable in this power scenario, if solar is proven cheaper, safer and less controversial?
I understand the nuclear industrial complex repeats ad nauseum that renewables can never scale etc. but in this application, solar would be safer, more cost effective, less polluting and more community acceptable.
posted by bystander at 8:47 PM on January 19, 2013 [2 favorites]



How Germany Is Getting to 100 Percent Renewable Energy
Since 2000, Germany has converted 25 percent of its power grid to renewable energy sources such as solar, wind and biomass.

Germans are baffled that the United States has not taken the same path. Not only is the U.S. the wealthiest nation in the world, but it’s also credited with jump-starting Germany’s green movement 40 years ago.

“This is a very American idea,” Arne Jungjohann, a director at the Heinrich Boll Stiftung Foundation (HBSF), said at a news conference Tuesday morning in Washington, D.C. “We got this from Jimmy Carter.”

“Everyone has skin in the game,” says Davidson. “The movement is decentralized and democratized, and that’s why it works. Anybody in Germany can be a utility.”
I wonder how much co2 is produced by biomass, though - would pellets are used to generate electricity in some places in Europe.
posted by Golden Eternity at 9:20 PM on January 19, 2013 [1 favorite]


would pellets are used to generate electricity

How much wood would a wood pellet plant use?
posted by stbalbach at 9:28 PM on January 19, 2013 [1 favorite]


How much wood would a wood pellet plant use?

Not sure if that was facetious, but I found this:

Biomass co-firing in high percentages - opportunities in conventional and advanced coalfired plants
• Biomass co-firing is established technology for co-firing percentages up to 10-20% (e/e)
• Biomass co-firing at high percentages (30-50% e/e) is (possibly) feasible
• Many technical bottlenecks in biomass co-firing are ash related.
(wood/cellulose pellets are also used for heating fuel).

This article claims Biomass burning is a major carbon polluter

Wikipedia: A report[4] by the Manomet Center for Conservation Sciences, "Biomass Sustainability and Carbon Policy Study" issued in June 2010 for the Massachusetts Department of Energy Resources, concludes that burning biomass such as wood pellets or wood chips releases a large amount of CO2 into the air, creating a "carbon debt" that is not retired for 20–25 years and after which there is a net benefit.

Sorry for the derail. The FPP article seems like a promising indication that long term solutions to global warming may not be impossible.
posted by Golden Eternity at 10:48 PM on January 19, 2013


I wonder how much co2 is produced by biomass, though - would pellets are used to generate electricity in some places in Europe.

The problem with burning biomass isn't the CO2 output-it is nominally carbon neutral. It is the loss of organic material going back in the soil as compost fertilizer. When farmers harvest a crop, typically the sileage (leftover inedible crop residue) is, ideally, either plowed under or fed to livestock than the manure is plowed into the soil. Using non edible food biomass is not good for sustainable agriculture. Using cleared wood from forest thinning project is probably a better scheme, not sure which Germany is using (BTW the second method IS being used in Oregon by a commercial forestry corporation with some success).

Like I said, it may not be possible to power this kind of chemical process in a start/stop way like most renewable power schemes have (its really their major weakness and in some locations their only). LOTS and LOTS of industrial power users CAN'T switch on and off without significant wasted product and fixed costs like heating up vats and cooling down stuff and so on, this is the reason we need a dependable, strong backbone grid system for our society-industrial power MUST be on and available 24/7 for our current setup, and good luck changing THAT. However for lots and lots of commercial and especially residential a supplemental renewable system makes a lot of sense.
posted by bartonlong at 10:54 PM on January 19, 2013


sigh...the main problem is that the oceans are quickly becoming devoid of fish because we assume we can just keep fishing them clean forever and put nothing back...because, for some idiotic reason we assume to do otherwise would violate the principle of 'least harm'. seed the ocean with a bit of iron, feed the plankton, the fish eat it...more fish, less dissolved carbon, less co2 in the atmosphere, cost miniscule.
posted by sexyrobot at 11:50 PM on January 19, 2013


The problem with burning biomass isn't the CO2 output-it is nominally carbon neutral. It is the loss of organic material going back in the soil as compost fertilizer. When farmers harvest a crop, typically the sileage (leftover inedible crop residue) is, ideally, either plowed under or fed to livestock than the manure is plowed into the soil. Using non edible food biomass is not good for sustainable agriculture. Using cleared wood from forest thinning project is probably a better scheme, not sure which Germany is using (BTW the second method IS being used in Oregon by a commercial forestry corporation with some success).

There is something of a problem concerning biomass in current EU RE policy in that all the EU Member States have set targets for achieving agreed fractions of total energy (ie not just electricity) from RE by 2020. Biomass is likely to be key to the changeover in electricity but also in heat and especially in transport. Biomass is currently the leading renewable heat source and is pretty much the only significant source of renewable transport within the EU. All good so far, but the problem: These targets have meant growth in the demand for biomass which the EU struggles to meet from internal supply. This means it has to look outward but there are problems with sourcing sufficient volume sustainably. How to make sure that you won't displace food crops is a big issue, as is whether biomass is actually at or close to being carbon neutral if you can't be sure how it was grown (i.e. with lots of fertiliser, etc) or if it has been shipped from India or somewhere similarly far away. The EU has talked about a certification scheme but I don't think that progress towards getting this right has been substantive so far.
posted by biffa at 4:37 AM on January 20, 2013


mary8nne: Is Carbon Sequestration actually taken seriously though? It has always sounded like an absurdity to me.

It is. An International Energy Agency document from two years ago suggested that CCS would account for as much decarbonisation globally as all renewable energy sources by 2030. Personally I really struggle to see how this could be the case when you consider that:

(1) it is a technology which barely qualifies as proven and is a long way from mature (capturing the CO2) combined with a technology which is unproven (permanently keeping the CO2 underground) and
(2) how little deployed CCS technology there is in the world. There are only a few plants with fitted scrubbers. New systems have encountered problems and uptake of the technology is slow. In the UK, the Government has been trying to give away a grant of £1bn for the last five years, so far without uptake.
posted by biffa at 4:51 AM on January 20, 2013 [4 favorites]


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