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I really hope this comes into fruition.There was a great radio 4 program that highlight the potential uses of CO2 in the production of various items. The problem was that the cost of production, and how we are used to low cost plastics.
This is something that is currently under development and being licensed for large-scale commercial production. This is one company active in the space:
Well of course. Plastics are syntasized from hydrocarbons and given sufficient electric power you can turn atmospheric CO2 and water into hydrocarbons. We've known how to do this with simple methane for over a hundred years and we have pilot plants for more complex hydrocarbons. The problem is where that electric energy comes from.
Here's hoping for continued progress in reducing the cost of solar panels, etc.
Newlight claims to have a new biocatalyst that is 9x more efficient than previous processes used in converting methane to plastic and that they can compete w/ petroleum based plastic on price when they scale up.
The one huge aspect this article doesn't even mention are the thermodynamics of the process. Of course CO2 can be used as a building block for plastic, but it contains far less energy than the plastic you want to create. That means you have to supply that energy difference somehow.
The reason we use mostly oil to synthesize plastic is that someone else already put in the energy to convert CO2: the plants.
Even though you can't avoid the thermodynamics here and cheat the energy difference, of course there could be more efficient, cheaper and cleaner ways to go from CO2 to plastic, and those would be interesting in terms of dealing with climate change.
Given the current solar boom, we'll probably end up using the same energy source that plants use. Perhaps even a chemical process similar to photosynthesis.
It's still would be more effective to use biomass to sequester the CO2 and then make biopolymers than it's to use an artificial process.
Also solar has it's own carbon footprint, and not as small as people think.
The raw materials for these panels are mined, transported, the factories in China that make those panels use likely coal as their primary energy source, then the panels are transported again and again and again, and finally installed and maintained by people who likely don't show up to work in an EV.
You need to be very careful abstracting the true carbon footprint of anything and sadly too many people seem to ignore this fact.
Just because the item you buy and it's use is environmentally friendly it doesn't mean that the supply chain is.
This solar has a carbon footprint argument is absurd. If you used this logic we would never have renewable energy because it creates a chicken and egg problem. It would only make sense if the amount of energy used to produce solar panels exceeded the amount of energy it produced over it's lifetime, which is not the case.
It does make a lot of sense to examine the expected EROI when installing them though. Buying power from the other side of a mountain might be a lot greener than installing solar panels in your own backyard (that probably requires much of the transmission infrastructure to already exist, but a lot of transmission infrastructure already exists).
No it's not an absurd argument, you need to understand the actual carbon footprint for the entire supply chain.
In this case you can easily end up releasing more carbon by building the solar panels and all the machinery needed for sequestering the CO2 than you can actually effectively sequester within the effectively lifespan of your machinery.
You also need to take into account in the cost since each dollar (or any other unit of currency) has a carbon footprint on it's own based on the economy it was generated in.
There is a good reason why some things are not effective, viable or just plain stupid, otherwise you end up planning your freaking solar roadways or worse building them.
This is what struck me when reading the article. The winner of the hackathon is the guy who goes out to the parking lot and plants a tree. :)
In all seriousness, they gather the solar energy themselves, absorb the CO2 themselves, after a small initial investment you can walk away and the result is plenty of useful materials (including bioplastics)!
Trees are a win-win all around, especially in urban areas.
They absorb CO2 and other particulate pollution, provide shade which has measurable reductions in cooling costs, divert storm water and improve property values.
The real question is, "Can CO2 be given more value by using it to make plastics than the value of the energy used to power the process?"
This is a much harder problem. A good start might be a thermodynamic analysis.
Ethylene monomers have an enthalpy of formation from pure CO2 and H2O of 12.9 kWh/kg, plus losses due to process inefficiency. It's only 7.3 kWh/kg if you have a "free" source of hydrogen to provide the remaining energy, but typically industrial hydrogen comes from fossil fuels.
Industrial electricity prices in the US and China are around 10c(=0.66 Yuan)/kWh, so that much electricity goes for about $1.30. But ethylene prices are only around $1.07/kg,[1] so from this admittedly simplistic analysis it would seem the answer is no, it's not worth it. This is before considering the extra energy required to concentrate CO2 from dilute form in the atmosphere or an exhaust flue.
Someone else on this thread said it best -- the tree wins the technology contest. Self replicating, solar powered, soil building, carbon sequestering, water/air cleaning, etc. Oh yeah, and trees are literally[2] what makes it rain.
[2] By transpiring coastal rainfall, trees "kick it back up" and transport water to the inner parts of the continent like an irrigation system. Hence why deforestation leads to desertification.http://www.nature.com/nature/journal/v496/n7445/abs/nature11...
Here's a crazy idea I've been thinking for a long time. Is tthere a way to artificially create a way to trap sunlight and turn it into gasoline in an artificial process. Basically what earth does in thousands of years but with human ingenuity we make it a lot faster and free reproducible in other countries.
I see the core problem as. We already have great gasoline infrastructure. It's very energy dense. We just need to learn how to make green gasoline.
We make a lot of green gasoline already. It's called biofuel. The problem is that it takes farmland away from producing food for people into producing food for cars. And cars are much hungrier, filling landscapes with rapeseed https://en.m.wikipedia.org/wiki/Rapeseed
The US navy is planning on introducing the ability to generate jet fuel from seawater on its nuclear aircraft carriers in the 2020s. The process works, it just takes a tremendous amount of energy (hence the nuclear carrier part) and it requires a lot of water to create a gallon of jet fuel (20,000 gallons I believe for a singe gallon of jet fuel).
The toughest part, however, is that the process would release methane gas into the air. So it's unclear if it's really greenhouse-gas neutral.
In theory, though, if you could trap the methane and then sequester the hydrocarbons you made, you'd have a way to pull CO2 out of the atmosphere.
EVs are simply better than gasoline for pretty much anything with wheels. And we have a great infrastructure for that too. There's no point in producing synthetic fuels for 99% of wheeled vehicles. Planes on the other hand are a different story.
This was debunked years ago. Making plastics from CO2 is possible, but an energy hungry process which does not suck up any relevant amount of carbondioxide from our atmosphere. It isn't going to be the climatesaver they claim it to be. This is not a manufacturing issue, but depends on basic thermodynamics.
That's for supercritical CO2 as it would be transported in pipelines, at a density about 0.6 times that of water.
IIRC we need to store many tens of Gigatonnes of CO2 per year. If you make it into plastic, you can divide by 5 (roughly). Total world plastic production is around 0.3 Gigatonnes
Sure but then we can just use the energy to suck all the co2 out of the atmosphere and blow it out into solar orbit or something. There are better materials to use for making plastics with infinite energy, although I'm probably not qualified to make that statement.
Why would fusion power result in "enourmous abundance" of usable energy? A fusion power plant would not run on magic, it is an extremely complex, very expensive high-tech system which requires human oversight, maintainance, and fuel.
Yep - our already built fission plants are starting to go out of business because the power they produce is too expensive. I don't think we should bank on fusion plants being incredibly inexpensive to operate.
Ted Grozier, flagship programme manager on the EnCO2re initiative, explains the thinking. He says: “The idea of a hackathon is you basically lock people in a room, you give them pizza and energy drinks, and they solve problems quickly.”
I always makes me sad when I see people talking about hackatons as a "tool" the can use by giving "pizza and energy" drinks. Hackatons have become a corporate tool.
Appart from things other comments have already mentioned there's some issue that the article doesn't properly reflect: Where does the CO2 come from?
You can grab the CO2 from the atmosphere and thus produce (temporary) negative emissions. But then you need even more energy in the first place. So naturally you'd get the CO2 from somewhere where you already have large amounts of CO2, e.g. a coal power plant. So you have created a justification to keep the coal plant running (with a supposedly imperfect co2 extraction process). How's that going to work out in a supposedly CO2 free energy future?
Also it should be considered that the CO2 in the plastic isn't gone for good. Plastic has a limited lifetime and will eventually end up in a landfill or a waste processing plant where it'll release its stored carbon back to the atmosphere.
So if your process is "burn coal -> capture CO2 -> use CO2 to create plastics -> plastic ends up in waste processing plant" you have delayed the emissions from the coal plant and you can argue that you have used the coal in a more efficient way, but the CO2 still ends up in the atmosphere.
There are many processes that produce CO2. The article mentions cement. Cement production accounts for about 5% of CO2 emissions according to a quick Google.
But you end up with a similar problem: You disincentivize carbon reductions in cement production.
If we ever want to get serious about climate change then cement has to reduce its environmental impact. This is a hard problem (I am actually right now researching for an article about the topic), but all models with serious carbon reductions assume that on the medium term co2 emissions have to go down ~95%. As there are other things were carbon reduction is really hard cement can't use up all the remaining 5%.
There are and were some startups trying to create greener cement, but all that went nowhere. The one that made most headlines - Novacem - went bankrupt and no longer exists.
But it might not even make that much sense even in that scenario... If our goal is to reduce the amount of CO2 in the atmosphere, it may be more effective to just add the renewable power source to the grid and further decarbonize our grid. Getting rid of all our coal plants would probably have a bigger impact than designing and building a system that sucks a bit of CO2 out of the atmosphere and makes plastic with it.
Turning CO2 from a coal plant into useful material seems like an oxymoron. The reason that we produce CO2 in the first place is that we get so much energy from turning it into CO2. Going the other way will cost about as much (probably more) energy than we got from burning the original fuel.
That is not to say that bad policy can't cause such practice.
I agree with most of what you say, and agree this is an uneconomical idea. However, I think the more likely scenarios at the end of the process are that the plastic either ends up in a landfill after use or ends up being recycled. Both of these outcomes will not release all the CO2 back into the atmosphere since common plastics do not break down when buried in landfills.
The 20% CO2 is great, but I'd rather see more innovation in replacing that 80% Petroleum with bioplastics. When the oil runs out we can solar up the wazoo, but if we can't find something alternative plastic sources we're going to have problems
There are reasonable plant plastic processes. The simple alcohols are pretty good chemical feedstocks and we are pretty good at making them from plants.
CO2 already has value, if it's concentrated enough (stack emissions, unfortunately, aren't). There are CO2 mines in multiple western US states where the CO2 is dug up, sent through pipelines, and reinjected into oil wells. "Enhanced oil recovery", they call it, and it's big business. So big, in fact, that the supply from the McElmo dome in the SW corner of Colorado, pipelined across the entirety of New Mexico, into Texas, is oversubscribed and you can't buy any.
CO2 needs hydrogen, pure and simple, to become almost any other substance of value (I suppose lithium extraction could use the gas instead of trona, but not a big market there considering the supply). Any plastic, polymer, or vegetation needs hydrogen to exist.
So the CO2 problem is the hydrogen problem, but on steroids. You can't get reduced atmospheric CO2 with hydrogen if making that same hydrogen molecule created 2 or 3 CO2 molecules. This leaves you with plant-based approaches (photosynthesis is ridiculously inefficient, which itself is probably a good thing considering how much we like some of the greenhouse effect), or "clean" hydrogen.
I don't know of any process that makes plastics directly from CO2, but the gas can be used to produce several intermediates.
Saudi Aramco recently acquired Novomer's Converge polyol technology, which uses CO2 to make polypropylene carbonate polyols. Polyols are a main component of polyurethanes. The Converge-based polyurethanes are used in coatings, adhesives, sealants and elastomers.
Covestro is also producing polyols made from carbon dioxide.
As mchannon noted, these companies cannot use the CO2 emitted from power plants. The gas needs to be pure so companies can do chemistry on it.
There are also some renewable routes to making plastics from CO2.
We already produce ethanol from sugar fermentation. This ethanol can be dehydrated to produce ethylene, the building block for polyethylene. Braskem is already doing this in Brazil. I believe Braskem is the ONLY company doing this, so that should tell you how cost effective the process is.
A company called Proterro was in the early stages of using a cyanobacteria that consumes bacteria to produce sugar. This sugar could then be fermented to produce ethanol, which could then be the feedstock for polyethylene.
Other companies have developed microorganisms that can ferment sugar to produce lactic acid. Polymerise this and you get polylactic acid (PLA), another plastic. This is one of the plastics used to make filament for 3D printers.
Other companies were developing micro-organisms that could produce polyhydroxalkanoates (PHAs).
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[ 82.2 ms ] story [ 1264 ms ] threadInstead, it seems to be preferred that you simply upvote the post without replying.
http://www.bbc.co.uk/programmes/b081lkm1
https://www.newlight.com/aircarbon/ https://www.newlight.com/newlight-technologies-signs-15-year... https://www.newlight.com/newlight-signs-10-billion-pound-pro...
Here's hoping for continued progress in reducing the cost of solar panels, etc.
http://www.biofuelsdigest.com/bdigest/2015/07/13/one-billion...
The reason we use mostly oil to synthesize plastic is that someone else already put in the energy to convert CO2: the plants.
Even though you can't avoid the thermodynamics here and cheat the energy difference, of course there could be more efficient, cheaper and cleaner ways to go from CO2 to plastic, and those would be interesting in terms of dealing with climate change.
Also solar has it's own carbon footprint, and not as small as people think.
The raw materials for these panels are mined, transported, the factories in China that make those panels use likely coal as their primary energy source, then the panels are transported again and again and again, and finally installed and maintained by people who likely don't show up to work in an EV.
You need to be very careful abstracting the true carbon footprint of anything and sadly too many people seem to ignore this fact.
Just because the item you buy and it's use is environmentally friendly it doesn't mean that the supply chain is.
In this case you can easily end up releasing more carbon by building the solar panels and all the machinery needed for sequestering the CO2 than you can actually effectively sequester within the effectively lifespan of your machinery.
You also need to take into account in the cost since each dollar (or any other unit of currency) has a carbon footprint on it's own based on the economy it was generated in.
There is a good reason why some things are not effective, viable or just plain stupid, otherwise you end up planning your freaking solar roadways or worse building them.
The guy that commutes in a coal rolling SUV pays more so he stops and buys an EV pickup instead.
The coal burning power station that he charges it with pays more so they get replaced with gas or solar or wind.
The company that ships the panels chooses between different shipping methods based on price, which includes a cost of carbon.
And so on. The magic of free markets (I'll end this sentence early since we're not doing politics this week.
In all seriousness, they gather the solar energy themselves, absorb the CO2 themselves, after a small initial investment you can walk away and the result is plenty of useful materials (including bioplastics)!
They absorb CO2 and other particulate pollution, provide shade which has measurable reductions in cooling costs, divert storm water and improve property values.
The real question is, "Can CO2 be given more value by using it to make plastics than the value of the energy used to power the process?"
This is a much harder problem. A good start might be a thermodynamic analysis.
Ethylene monomers have an enthalpy of formation from pure CO2 and H2O of 12.9 kWh/kg, plus losses due to process inefficiency. It's only 7.3 kWh/kg if you have a "free" source of hydrogen to provide the remaining energy, but typically industrial hydrogen comes from fossil fuels.
Industrial electricity prices in the US and China are around 10c(=0.66 Yuan)/kWh, so that much electricity goes for about $1.30. But ethylene prices are only around $1.07/kg,[1] so from this admittedly simplistic analysis it would seem the answer is no, it's not worth it. This is before considering the extra energy required to concentrate CO2 from dilute form in the atmosphere or an exhaust flue.
Someone else on this thread said it best -- the tree wins the technology contest. Self replicating, solar powered, soil building, carbon sequestering, water/air cleaning, etc. Oh yeah, and trees are literally[2] what makes it rain.
[1] http://asia.nikkei.com/Markets/Commodities/Ethylene-prices-u...
[2] By transpiring coastal rainfall, trees "kick it back up" and transport water to the inner parts of the continent like an irrigation system. Hence why deforestation leads to desertification. http://www.nature.com/nature/journal/v496/n7445/abs/nature11...
I see the core problem as. We already have great gasoline infrastructure. It's very energy dense. We just need to learn how to make green gasoline.
The toughest part, however, is that the process would release methane gas into the air. So it's unclear if it's really greenhouse-gas neutral.
In theory, though, if you could trap the methane and then sequester the hydrocarbons you made, you'd have a way to pull CO2 out of the atmosphere.
Nobody knows what it's really producing.
IIRC we need to store many tens of Gigatonnes of CO2 per year. If you make it into plastic, you can divide by 5 (roughly). Total world plastic production is around 0.3 Gigatonnes
1 - https://www.co2.earth/global-co2-emissions
Perhaps self-replicating solar array in space level of abundance?
You can grab the CO2 from the atmosphere and thus produce (temporary) negative emissions. But then you need even more energy in the first place. So naturally you'd get the CO2 from somewhere where you already have large amounts of CO2, e.g. a coal power plant. So you have created a justification to keep the coal plant running (with a supposedly imperfect co2 extraction process). How's that going to work out in a supposedly CO2 free energy future?
Also it should be considered that the CO2 in the plastic isn't gone for good. Plastic has a limited lifetime and will eventually end up in a landfill or a waste processing plant where it'll release its stored carbon back to the atmosphere.
So if your process is "burn coal -> capture CO2 -> use CO2 to create plastics -> plastic ends up in waste processing plant" you have delayed the emissions from the coal plant and you can argue that you have used the coal in a more efficient way, but the CO2 still ends up in the atmosphere.
But you end up with a similar problem: You disincentivize carbon reductions in cement production.
If we ever want to get serious about climate change then cement has to reduce its environmental impact. This is a hard problem (I am actually right now researching for an article about the topic), but all models with serious carbon reductions assume that on the medium term co2 emissions have to go down ~95%. As there are other things were carbon reduction is really hard cement can't use up all the remaining 5%.
There are and were some startups trying to create greener cement, but all that went nowhere. The one that made most headlines - Novacem - went bankrupt and no longer exists.
That is not to say that bad policy can't cause such practice.
The 20% CO2 is great, but I'd rather see more innovation in replacing that 80% Petroleum with bioplastics. When the oil runs out we can solar up the wazoo, but if we can't find something alternative plastic sources we're going to have problems
CO2 needs hydrogen, pure and simple, to become almost any other substance of value (I suppose lithium extraction could use the gas instead of trona, but not a big market there considering the supply). Any plastic, polymer, or vegetation needs hydrogen to exist.
So the CO2 problem is the hydrogen problem, but on steroids. You can't get reduced atmospheric CO2 with hydrogen if making that same hydrogen molecule created 2 or 3 CO2 molecules. This leaves you with plant-based approaches (photosynthesis is ridiculously inefficient, which itself is probably a good thing considering how much we like some of the greenhouse effect), or "clean" hydrogen.
Saudi Aramco recently acquired Novomer's Converge polyol technology, which uses CO2 to make polypropylene carbonate polyols. Polyols are a main component of polyurethanes. The Converge-based polyurethanes are used in coatings, adhesives, sealants and elastomers.
Covestro is also producing polyols made from carbon dioxide.
As mchannon noted, these companies cannot use the CO2 emitted from power plants. The gas needs to be pure so companies can do chemistry on it.
There are also some renewable routes to making plastics from CO2.
We already produce ethanol from sugar fermentation. This ethanol can be dehydrated to produce ethylene, the building block for polyethylene. Braskem is already doing this in Brazil. I believe Braskem is the ONLY company doing this, so that should tell you how cost effective the process is.
A company called Proterro was in the early stages of using a cyanobacteria that consumes bacteria to produce sugar. This sugar could then be fermented to produce ethanol, which could then be the feedstock for polyethylene.
Other companies have developed microorganisms that can ferment sugar to produce lactic acid. Polymerise this and you get polylactic acid (PLA), another plastic. This is one of the plastics used to make filament for 3D printers.
Other companies were developing micro-organisms that could produce polyhydroxalkanoates (PHAs).