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New Solar Cells Can Convert CO2 Into Hydrocarbon Fuel (nextbigfuture.com)
"Researchers at the University of Illinois at Chicago have engineered a potentially game-changing solar cell that cheaply and efficiently converts atmospheric carbon dioxide directly into usable hydrocarbon fuel, using only sunlight for energy," reports Next Big Future. Slashdot reader William Robinson writes:
This artificial leaf delivers syngas, or synthesis gas, a mixture of hydrogen gas and carbon monoxide. Syngas can be burned directly, or converted into diesel or other hydrocarbon fuels. The discovery opens up possibilities of clean reusable energy.
"A solar farm of such 'artificial leaves' could remove significant amounts of carbon from the atmosphere and produce energy-dense fuel efficiently..." according to the article, which adds that the process could prove useful in the high-carbon atmosphere of Mars. "Unlike conventional solar cells, which convert sunlight into electricity that must be stored in heavy batteries, the new device essentially does the work of plants, converting atmospheric carbon dioxide into fuel, solving two crucial problems at once."
"A solar farm of such 'artificial leaves' could remove significant amounts of carbon from the atmosphere and produce energy-dense fuel efficiently..." according to the article, which adds that the process could prove useful in the high-carbon atmosphere of Mars. "Unlike conventional solar cells, which convert sunlight into electricity that must be stored in heavy batteries, the new device essentially does the work of plants, converting atmospheric carbon dioxide into fuel, solving two crucial problems at once."
Whether or not this is interesting really depends on the expected power / area and cost (production and operating) of an engineering version. It is better than bio-fuels by those measures?
CO is usable and can be 'burned' which results in CO2 (oxidation.)
Because so far most of these carbon removing technologies fall way short of just planting a grove of trees. This seems like one of those problems where maybe nature is handing us a simpler solution. But for the sake of science (and keeping that funding flowing) we go out of our way to make a less efficient, more expensive machine to do the job that a tree will do for free.
Syngas can be converted to gasoline or diesel via the Fischer-Tropsch process.
love is just extroverted narcissism
I have a nice way to transform Hydrocarbon fuels into CO2
aaaaaaa
Because if not, I fail to see any significant advantage.
I'm not saying this to be just contradictory to any new development in the energy industry... this is a serious question. If the amount usable energy that can be obtained by the fuel it produces in terms of energy per dollar of investment spent on the technology is not any better than what you can get from modern efficient solar cells then it makes much more sense to use solar power and electricity instead.
File under 'M' for 'Manic ranting'
On mars? Yes much better than a tree.
Yes!
Where you can grow plants and get bio-diesel, plants are in competition with this device.
Where you can't grow plants efficiently or at all - like Mars or my apartment balcony (they keep dying because I keep forgetting to water them), this may be interesting if it's better than other sunlight-to-energy systems.
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It is not better than photovoltaic cells. It is just more compatible with our current energy infrastructure. There are billions of cars out there that run on hydrocarbons. It is way easier to give them a clean source of hydrocarbons than to scrap them and build billions of electric cars.
entropy happens
It does solve the storage problem though. Unlike plain solar, you don't need to buy a huge bank of batteries if you want to use it later. Much of the efficiency of solar comes from the fact that you get electricity directly, and electricity is what you use. As soon as you want the energy in a lightweight and portable form, solar loses its efficiency.
So the main competition for this technology is not regular solar, but plants and algae, which are much cheaper to grow.
What about seawater?
All of the other crap in seawater makes a mess of the delicate chemistry involved. As with most of these things, it needs pure water, or it will quickly stop working.
It is also clear that it will *consume* fresh water, which adds yet another drain on our already overtaxed fresh water supply.
TANSTAAFL
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Syngas can be converted to gasoline or diesel via the Fischer-Tropsch process.
Which also generates a bunch of heat at temperatures moderately above water's boiling point, which must be removed to keep the process in its optimal temperature range. This is suitable for co-generation, producing more electriity than is needed to run the plant. So in addition to clean diesel fuel (or gasoline with a little refining) and a bit of chemical feedstock, you get to feed the grid.
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
It doesn't add to the problem
Neither do photo-voltaic cells, and I notice that the article carefully avoided any mention of efficiency. I expect that is where this thing goes off the rails. If it can't muster at least 10% efficiency (comparable to an EV powered by solar cells), then whats the point? Photovoltaics would be better.
The whole idea of explosion powered vehicles is pretty stupid when faced with the infrastructure to transmit electrical power in vast quantities. 100 years ago, that infrastructure did not exist, and there was considerable doubt as to its ability to scale. Today, we have a successful, proven system that can scale to any amount needed for relatively cheap. Its time to move on from flammable materials as fuels.
I wish I had a good sig, but all the good ones are copyrighted
And 20 years later when the patent expires and no one wants a functioning, researched, unencumbered technology? How does your conspiracy handle that scenario?
I'm not the poster you are talking to, but I will give a reason why useful patent-unencumbered things may never make it to market, and by extension, why a competitor may want to buy up the rights to promising technology and put it on the shelf, knowing that economic forces alone will keep it from seeing the light of day even after the patents expire:
Many technologies are "partially researched" or "completely researched but still millions of dollars away from going to market for the first time." Maybe the device or drug or whatever requires expensive government approval, or maybe there are other "up front costs" that will be the burden of only the first company that brings it to market.
Without patent protection, it's a hard sell to investors if they know that 1) the first company to bring this to market will have $MILLIONS more in costs than any other company who brings it to market, and 2) without a patent, the "exclusivity window" will be very short: Just the time it takes for some other company to smell money and ramp up production.
This is one reason why some non-FDA-approved or "FDA-listed-as-schedule-1-because-nobody-has-shown-the-FDA-there-is-any-medical-use-for-it" drugs which are off-patent or patent-ineligible never make it to market: The cost of FDA approval is borne by the company that wants to bring it to market first, but once it's approved it can be copied fairly quickly.
Well-known examples include medicinal use of marijuana in the United States from the mid-20th century until 10 or 20 years ago (I think it's still technically not FDA-approved but the feds are looking the other way in states that have laws that allow for its use) and ibogaine as a treatment for opiate addictions.
Knowledge is how to play a game, intelligence is how to win, wisdom is knowing what game to play.
Then in ten years we will wonder what the fuck happened.
The main reason most of these things don't come to market is that inventions are coming so rapidly that something BETTER comes along and obsoletes them before they reach manufacturing and deployment.
Nevertheless, enough make it that things are improving substantially. For instance: Photovoltaic prices recently "crossed-over" grid power costs for much of the temperate-zone sunny sites - even without further government subsidies on manufacture and installation. That's a BIG change from a decade ago.
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
Dude this is older than photography ! :
https://upload.wikimedia.org/wikipedia/commons/3/33/A_Peep_at_the_Gas_Lights_in_Pall_Mall_Rowlandson_1809.jpg
By the mid to late 19th century sizable infrastructure was built to produce a mixture of carbon monoxide and hydrogen in huge complicated plants, and distribute it in major cities through pipes, for lighting - especially street lights - and maybe cooking and heating.
https://en.wikipedia.org/wiki/...
Coal gasification processes to create syngas were used for many years to manufacture illuminating gas (coal gas) for gas lighting, cooking and to some extent, heating, before electric lighting and the natural gas infrastructure became widely available.[citation needed] Although the syngas chemical composition can vary based on the raw materials and the processes, the syngas from coal gasification generally is a mixture of 30 to 60% carbon monoxide, 25 to 30% hydrogen, 5 to 15% carbon dioxide, and 0 to 5% methane. It also contains lesser amount of other gases.[19]
The syngas produced in waste-to-energy gasification facilities can be used to generate electricity.
Of course, a leak or poor piping might make you pass out and die from carbon monoxide poisoning or perhaps you might poison yourself with a gas stove. But indoor (or outdoor) open fires of wood or coal had their share of problems too.
We already have a working prototype cell that turns sunlight and CO2 into a burnable fuel.
You might already be familiar with them. They call them "trees."
You convert CO2 in CO. Then you oxidize it to get CO2 back.
No CO2 sequestration at all!
So, how would this be better than photovoltaic cells?
It's better because every time there's a story on photvoltaic cells, a bunch of self-appointed geniuses yell: "I'm the first person to realize that the sun doesn't shine all day! It won't do any good without energy storage!!1!"
Well, here's a solar technology with built-in energy storage.
Energy density (I assume you mean energy produced in a given amount of time with a given surface area, e.g. watts/square centimeter) isn't the only factor that counts.
How you intend to use or store the energy is also a factor.
Pure solar typically produces either heat (sterling engine) or DC power (typical solar cell) as its direct output. Some solar devices include add-ons to convert that energy into battery storage, mechanical energy, AC power, fuel, or some other form of energy.
This device appears to produce useful chemicals (hydrogen gas and carbon monoxide gas) as its direct output.
The decision of which is "better FOR YOU" needs to include the question "what form do you want the energy to be in, and what's the best way to get from sunlight to that form?"
Unless you want one of the "direct outputs" listed above, you are probably looking at using a multi-step process and the "energy density" of the first step is no longer the only factor.
If you do want one of the "direct outputs" listed above (DC power, heat, or CO+H2) , you probably will go with the technology that gives it to you directly unless there's a cheaper, but possibly more-complicated, process to get what you want (maybe you want CO+H2 but your investor or the agency that funds your grants will give you money for "proven technologies" but not for "novel or unproven ones" making the cost of traditional solar much cheaper FOR YOU).
Knowledge is how to play a game, intelligence is how to win, wisdom is knowing what game to play.
Powering transportation solely on electricity gives the state the ability to decide when, where, and how much you can use because it's a public utility but under the legal control of the state.
Uh, what? Powering transportation solely with electricity is the only way an individual can become energy independent. I can install enough photovoltaic panels to power a Tesla for literally all of my driving needs (I fly when I travel long distances). Those panels are not only not a public utility, but quite specifically my private property. If I lived in the country, I could put up a windmill, either instead of or in addition to photovoltaic panels. Again, private property. Install enough of them, and a battery bank in the basement, and I can disconnect my house from that public utility too.
I certainly can't drill an oil well in my backyard and run an oil refinery in my basement. I can't strip mine my backyard for coal and run a steam-powered car. I can't cut enough trees to burn wood and run a steam-powered car either. I can't even plant enough switchgrass, harvest it, and make enough ethanol. Even if I could strip mine my backyard for coal, it would have to be half a mile thick to handle my transportation needs for the rest of my life, and coal just doesn't come that way.
Neither fossil fuels nor biofuels can fuel my transportation needs. Either I'm not allowed to utilize them (and wouldn't want to, because of the stench), or they literally aren't energy-dense enough, respectively. Biofuels depend on plants, which are lucky to convert even 3% of the sunlight falling on them, and they convert into biomolecules that I have to do something dramatic to in order to utilize their energy (usually at further loss). Commercial off the shelf photovoltaic panels convert sunlight at 22% efficiency, directly into electricity I can use, or can convert into something I can use with well-understood, cheap circuitry.
Powering transportation, and indeed everything else, solely on electricity is the one and only path to personal energy independence that can be pursued by more than a handful of farmers with massive amounts of acreage. And it's physically possible today. Right now. For everybody in the world who lives in low density housing. It's not financially possible for most just yet, but at least physics isn't preventing it.
And how much energy does it take to extract CO2 from the atmosphere regardless of the conversion process?
You don't have to extract CO2 from the atmosphere. You could instead extract it from the exhaust pipe of a power plant.
How pure does the feedwater have to be to avoid poisoning the catalyst or the membrane? Maybe subtract the energy required to purify it.
What energy? Reverse osmosis and dionization resins can do it physically and chemically. No energy needed, aside from the pressure needed for RO to work. If you use a fiber/carbon/DI system then gravity is enough. You'll have to recharge the DI resins chemically more often though.
Solar Impulse 2 has no payload beside itself and one guy. I will agree that commercial flight will be a sound possibility, but not of the kind that does transportation of passengers and air mail.
We do have 1000 mpg cars. They barely fit the definition of a car, and would likely be a death trap on the roads. In fact, you may as well build a bicycle/tricycle in the same shape and reach legal road speeds. But to fit four people and minimal luggage you'll have a lot of trouble reaching even 100 mpg (while not topping out a hybrid's battery on the way)
PV panels generate very little power on an overcast, winter day. In fact, in Germany, even on a good day they average under 1 full sun hour equivalent and that includes sunny days. It varies depending on where you live. You need to calculate the amount of overcapacity ijn panels you'd need to cover a weeks worth of home and car usage first, then you can start talking about battery sizes. A fridge size battery won't keep you going for a week even if you're energy use is half of the average home. A battery can only hold so much energy, you can't carry over for multiple weeks unless you buy a battery that is five or maybe even ten times the size you need just manage daily usage during sunnier seasons.
Saying it sounds easy till you do the math. Calculate the panels and battery capacity required, the cost will be a lot higher than you seem to think. Most people significantly underestimate the cost of such a system until they do the math.
This is already done for CO2 purification plants. Where do you think the CO2 for dry ice, carbonation, flash-freezing, etc. comes from? And don't forget that CO2 (that evil gas that's supposedly killing the planet) only makes up 0.04% of the atmosphere.
Here is the basic construction of the device from TFA:
"The UIC artificial leaf consists of two silicon triple-junction photovoltaic cells of 18 square centimeters to harvest light; the tungsten diselenide and ionic liquid co-catalyst system on the cathode side; and cobalt oxide in potassium phosphate electrolyte on the anode side."
So, the cathode is immersed in a combination of water and ethyl-methyl-imidazolium tetrafluoroborate (from TFA).
The anode is immersed also in an electrolyte.
The result is that "hydrogen and carbon monoxide gas bubble up from the cathode, while free oxygen and hydrogen ions are produced at the anode." (From TFA)
There's a big piece missing here: how does the CO2 from the atmosphere get to the cathode to be catalyzed, as it is immersed in this ionic fluid? Where does the Hydrogen come from - the electrolyte? It must, because there is no other place for it to come from. This means that the electrolyte is consumed unless it reclaims the Hydrogen, which we've been told is not the point.
So, the questions I have are:
1) How does CO2 get from the atmosphere to the cathode?
2) If the electrolyte is consumed in the process, does the H come from the water in the mix or from the ethyl-methyl-imidazolium tetrafluoroborate? (Slightly less bad if all we have to do is add water, but the fact they don't answer this question leads me to believe the H comes from the ethyl-methyl-imidazolium tetrafluoroborate)
3) Since we're releasing H and CO from the electrolyte in which the cathode is immersed, then we must also necessarily release Oxygen, both from the CO2, and from the electrolyte if it is the water being electrolyzed. Why do they not mention Oxygen bubbling up from the cathode, as it must?
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Of course, it must be said that by now we also have an infrastructure to power those explosion-powered vehicles.
Contrary, say, to the claims of some that hydrogen would be the new way to go. And insisting the infrastructure is already there, so it would be cheap to implement. Alas, our infrastructure for gasoline is NOT suited for hydrogen, and all the pipelines and storages would need a complete overhaul, making it prohibitively expensive for little added benefit.
On the other hand, artificial gasoline or syngas *CAN* use exactly the same infrastructure we already have.
You're last sentence, thus, seems rather to come forth from personal ideological preferences, rather than objective reasons. When looking at it economically, it does not follow one should move on, provided the efficiency of the system is high enough. Looking at it environmentally, it is not clear one should move on, since with this system, it would be CO2 neutral. Looking at it technically, there is no reason to move on, since the infrastructure is already there and poses no technical problems.
Not to say electricity won't trump every other energy/system out there in the end - it did with streetlights that used to be all on gas - but it foremost will only transplant those systems, where the advantages are most clear. There were the alternative systems are not inferior (in certain situations), they won't (rapidly) get replaced. The main argument and reason to go for electric cars, for instance, is the environmental issue. But if that were to disappear (with syngas or artificial petrol that re-uses the CO2) an important reason in favour of electric cars would disappear as well. For airplanes, which need light weight, high-density energy, it's even more clear that gasoline won't go away for batteries for a long time... And even Musk agreed that rockets will never fly on battery-packs. ;-)
There are whole industries needing, and revolving around petrol. This won't change any time soon. It would be a good thing if technologies like these would take care of the major disadvantages it has, in the meantime.
That said, being realistic: it all depends on the efficiency, and I don't see anywhere mentioned in the article what the de facto efficiency was of the system - which is always a bad sign.
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