Converting Sunlight Into Liquid Fuel With a Bionic Leaf

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Converting Sunlight Into Liquid Fuel With a Bionic Leaf

Posted by Soulskill on Wednesday February 11, 2015 @05:29AM from the who-needs-dead-dinosaurs dept.

hypnosec writes: Artificial leaf techology made waves the moment it was announced by Daniel Nocera back in 2011. His latest research, published in PNAS, involves gathering hydrogen from this artificial leaf, carbon dioxide from another source, and feeding it to Ralstonia eutropha bacteria to create liquid fuel. Once the materials are fed to the bacteria, "An enzyme takes the hydrogen back to protons and electrons, then combines them with carbon dioxide to replicate—making more cells. Next, ... new pathways in the bacterium are metabolically engineered to make isopropanol." Researchers say the same process could be used to make vitamins.

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Curiosity question - by Anonymous Coward · 2015-02-11 05:33 · Score: 1

Honestly, how many stoners saw the phrase "Bionic leaf" and went "WOOHOO!" at the title before being very disappointment at the summary/article?
Animal, not plant by MrLogic17 · 2015-02-11 05:36 · Score: 4, Informative

The headline implies that we have a machine replicating the process of a plant. The summary indicates that what they have is a vat of bacteria that are making alcohol. Not nearly as attention grabbing, considering mankind has been using yeast & bacteria to make alcohols of various forms since the dawn of time.
If they have a more efficient process with simpler (cheaper) inputs, kudos to them. But this ain't no artificial leaf.
1. Re:Animal, not plant by itzly · 2015-02-11 05:40 · Score: 2
  
  mankind has been using yeast & bacteria to make alcohols of various forms since the dawn of time
  Not from hydrogen and carbon dioxide, though.
2. Re:Animal, not plant by gstoddart · 2015-02-11 05:50 · Score: 5, Insightful
  
  The summary indicates that what they have is a vat of bacteria that are making alcohol
  Hmmmm ... are you sure?
  
  Their work integrates an "artificial leaf," which uses a catalyst to make sunlight split water into hydrogen and oxygen, with a bacterium engineered to convert carbon dioxide plus hydrogen into the liquid fuel isopropanol.
  
  So, they're clearly doing more than just making alcohol with yeast.
  
  "This is a proof of concept that you can have a way of harvesting solar energy and storing it in the form of a liquid fuel
  In fact, I'd say it sounds quite different.
  
  --
  Lost at C:>. Found at C.
3. Re:Animal, not plant by rgbatduke · 2015-02-11 06:41 · Score: 1
  
  That's right, I like to include Nitrogen and Phosphorus and Uranium in my beer. None of this wussy carbon, oxygen and hydrogen. You know you've been drinking when you drink molten thorium fluoride salts.
  Oh, you mean from hydrogen and carbon dioxide only...
  Never mind.
  
  --
  Even when the experts all agree, they may well be mistaken. --- Bertrand Russell.
4. Re:Animal, not plant by taiwanjohn · 2015-02-11 08:20 · Score: 1
  
  For actual artificial photosynthesis, check out Nate Lewis's work at Cal-Tech. In a nutshell: They note that natural photosynthesis is only about 2% efficient, so they are looking to improve on nature in this process, using off-the-shelf semiconductor printing processes. IIRC, they build a "forest" of upright conductive columns a few nano-meters apart, in order to mimic the band-gap of visible photons. He describes it in some detail in this lecture from a couple of years ago.
  
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5. Re:Animal, not plant by jdschulteis · 2015-02-11 13:46 · Score: 1
  
  If they have a more efficient process with simpler (cheaper) inputs, kudos to them. But this ain't no artificial leaf.
  It's a two-step process.The artificial leaf step uses sunlight to split water. The second step has bacteria combine the resulting hydrogen with carbon dioxide to produce isopropanol. Rather different from the time-tested use of yeast to convert sugars into ethanol.
6. Re:Animal, not plant by jdschulteis · 2015-02-11 13:56 · Score: 3, Insightful
  
  If it is so good, why not just store the hydrogen for fuel? Wouldn't it be cheaper/easier to skip the last steps?
  Hydrogen is difficult to store in a lightweight, compact system. One good way to store hydrogen is to chemically combine it with carbon and oxygen and put the resulting liquid in tanks at ordinary temperatures and pressures.
Re:I'd be more impressed... by Ginger+Unicorn · 2015-02-11 05:54 · Score: 1

If you want a break you can eat off a plate like everyone else.

--
(1.21 gigawatts) / (88 miles per hour) = 30 757 874 newtons
Re:That's nothing by l0ungeb0y · 2015-02-11 05:55 · Score: 1

When the shit dries, it can be used as fuel.
Re:I'd be more impressed... by codeButcher · 2015-02-11 05:57 · Score: 1

I'd be more impressed if they could change cucumbers into sunlight.
I've been working on it at the Academy for years. I'm close to a break trough, but I need more funding and a bit more time.
Some people have the sun shine out of their arses. You should co-op them and feed them only cucumbers.

--
Free, as in your money being freed from the confines of your account.
Re:Bionic. by BreakBad · 2015-02-11 05:57 · Score: 1

Got clicks
energy balance doesn't work out by Noah+Haders · 2015-02-11 05:59 · Score: 3, Interesting

The energy balance doesn't work out here. Max solar intensity is 1 kw / m^2, or 1 kj per square meter every second, or 3.6 MJ per square meter per hour. A gallon of gasoline is 120 MJ. So assuming 100% efficiency and 100% peak sunlight, it would take 30 hours to make a gallon of gas from one square meter of artificial leaf. Considering the average solar intensity is about 10% the max, and any process involving the sun is max 20% efficient, it starts to take a very long time to make one gallon of gas. Not even including the energy requirements of the leaf / enzyme process.
1. Re:energy balance doesn't work out by itzly · 2015-02-11 06:15 · Score: 1
  
  And what happens if you use 100 square kilometer instead of a square meter ?
2. Re:energy balance doesn't work out by gstoddart · 2015-02-11 06:18 · Score: 3, Funny
  
  Hmmmm .... 100 square kms ... producing flammable alcohol.
  Have you seriously thought about this?
  The first guy to realize he can light a match and have hilarity ensue will probably create something visible from orbit, and get himself a Darwin award.
  Actually, scratch that ... bring it on! That would be funny.
  
  --
  Lost at C:>. Found at C.
3. Re:energy balance doesn't work out by grimmjeeper · 2015-02-11 06:19 · Score: 1
  
  What does gasoline have to do with the isopropanol they are creating here?
4. Re:energy balance doesn't work out by itzly · 2015-02-11 06:22 · Score: 1
  
  Have you seriously thought about this?
  Yeah, I figured that somebody could be clever enough to not leave the alcohol out in the open where it can evaporate away.
5. Re:energy balance doesn't work out by Smidge204 · 2015-02-11 06:25 · Score: 1
  
  It's not at all clear what you're trying to prove or argue....
  The process produces isopropyl alcohol, not gasoline.
  The published article abstract clearly states that the overall efficiency for the process is "up to" 3.2% efficient.
  No claim was made as to the rate of production.
  Basically, while your math is correct it's completely irrelevant and inapplicable here. Thanks for sharing, I guess?
  =Smidge=
6. Re:energy balance doesn't work out by mlts · 2015-02-11 06:35 · Score: 1
  
  I wonder why isopropyl alcohol is used. If I had the choice of alcohols, I'd go with ethanol, just because it is the safest in the bunch, and a lot of vehicles can use some alcohol mix (E85) without damage.
7. Re:energy balance doesn't work out by itzly · 2015-02-11 06:39 · Score: 1
  
  If I had the choice of alcohols
  They probably didn't.
8. Re:energy balance doesn't work out by gstoddart · 2015-02-11 06:40 · Score: 1
  
  What, and spoil all the fun?
  Sorry, but if you have 100 square kms of alcohol producing farm ... someone is going to be looking at that.
  
  --
  Lost at C:>. Found at C.
9. Re:energy balance doesn't work out by smithmc · 2015-02-11 06:48 · Score: 2
  
  I don't know, except that the energy density of propanol is roughly similar to that of gasoline.
  
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10. Re:energy balance doesn't work out by Bob+the+Super+Hamste · 2015-02-11 07:36 · Score: 1
  
  If you have a vehicle that can run on E85 running on isopropanol wouldn't be a problem. Going up to butanol would be even better as it can basically be use in unmodified gasoline engines. As you point out neither of these is safe for human consumption but then neither is gasoline.
  
  --
  Time to offend someone
11. Re:energy balance doesn't work out by itzly · 2015-02-11 08:25 · Score: 1
  
  This would be just another facility that could go boom that we'd have to secure
  All you need to do is pipe the alcohol to a central storage facility, and then secure that. People routinely secure storage facilities containing in excess of 100.000 cubic meter of crude oil and derivatives, so this would be fairly easy.
12. Re:energy balance doesn't work out by Noah+Haders · 2015-02-11 10:44 · Score: 2
  
  134 billion gallons. based on your math, it's 140,000 km^2 of bionic leaf to make the gasoline for USA.
  134 billion gallons / (266,666 gallons per day per 100 square km (calculated above) * 365)
  What else is 140,000 square km? new York state. so is north Carolina. so is iowa. it's a lot of room.
  another perspective: it took millions of years of sunshine to grow plants to feed dinosaurs to be melted into oil and used today. it's really hard to replace that with a solution that runs in steady state, as in we produce enough for our annual consumption in one year. Maybe we need a dyson sphere...
13. Re:energy balance doesn't work out by Noah+Haders · 2015-02-11 10:45 · Score: 1
  
  it's just an order of magnitude thing. Fermi approximation. converting the energy in from sunline to energy out in terms of a unit we use each day.
14. Re:energy balance doesn't work out by Noah+Haders · 2015-02-11 10:46 · Score: 1
  
  it's just a quick Fermi approximation. it's a useful way to get a quick estimate of something within an OM or so.
15. Re:energy balance doesn't work out by Smidge204 · 2015-02-12 22:44 · Score: 1
  
  But the approximation makes no sense since it has zero applicability to the topic at hand. It's like estimating the number of piano tuners in Chicago by starting with the number of cab drivers in New York and concluding that light rail public transit isn't viable in rural Iowa.
  Just because the math works doesn't mean it's apropos of anything.
  =Smidge=
16. Re:energy balance doesn't work out by Noah+Haders · 2015-02-13 02:13 · Score: 1
  
  It's like estimating the number of piano tuners in Chicago by starting with the number of cab drivers in New York and concluding that light rail public transit isn't viable in rural Iowa.
  so you're saying that even though the methods are roundabout, the conclusion is sound. I agree!
17. Re:energy balance doesn't work out by Smidge204 · 2015-02-14 04:38 · Score: 1
  
  so you're saying that even though the methods are roundabout, the conclusion is sound. I agree!
  No, I'm saying your conclusion has nothing to do with your opening premise.
  I already said there's nothing wrong with your math.... it's simply irrelevant to your opening premise and unrelated to the topic at hand.
  You start by stating that the energy balance doesn't work. Nothing you said demonstrates that it doesn't work, and the assumptions you make (e.g. gasoline, efficiency) have nothing to do with the main article.
  =Smidge=
18. Re:energy balance doesn't work out by Noah+Haders · 2015-02-14 05:58 · Score: 1
  
  The point is, the article says that this bionic leave can be used to create fuel. What I'm arguing is that fuel requires so much energy that there's no way the bionic leaf capturing energy from the sun could produce enough fuel to meet our needs, using practical assumptions.
  The honest truth is there is a ridiculous amount of energy in a gallon of gasoline. It's like gods energy source. it's extraordinarily energy dense. it's a liquid at room temperatures. it's relatively non-toxic in that it won't kill you right away. It's relatively energy in that if you spell it it's not going to burst into flames. Even if you throw a match on it the surface will light on fire but only in the presence of oxygen. It will never explode unless you actively turn it into an aerosol. We've gotten good enough at refining and distribution that it's relatively cheap and ubiquitously available. It's really really hard for any alternative fuel to compete with gasoline, because gasoline is gods fuel.
19. Re:energy balance doesn't work out by Smidge204 · 2015-02-14 08:21 · Score: 1
  
  The point is, the article says that this bionic leave can be used to create fuel.
  And that's exactly what it does.
  
  What I'm arguing is that fuel requires so much energy that there's no way the bionic leaf capturing energy from the sun could produce enough fuel to meet our needs, using practical assumptions.
  But at no point did you include how much energy we'd actually need, nor did you account for how much space in total we'd need to dedicate to harvesting in order to meet that demand. Only after including those factors could you argue that the bionic leaf could not meet our needs...
  
  The honest truth is there is a ridiculous amount of energy in a gallon of gasoline.
  About 36 KWHr. That's pretty tame; a gallon of diesel has about four times as much... Maybe you have a strange concept of "ridiculous" amounts of energy, though.
  And while liquid hydrocarbons are fairly good in terms of specific energy, they are horribly inefficient compared to alternatives. I suppose it's good that you can easily carry that much energy around with you when you will inevitably piss 80% of it away as waste.
  And I'm pretty sure "god's fuel" would be hydrogen, used in the form of nuclear fusion. That literally powers the universe and is the source of all complex matter that we know of.
  =Smidge=
20. Re:energy balance doesn't work out by Noah+Haders · 2015-02-14 10:26 · Score: 1
  
  first, diesel is maybe 10-15% more energy rich than gasoline.
  
  But at no point did you include how much energy we'd actually need, nor did you account for how much space in total we'd need to dedicate to harvesting in order to meet that demand. Only after including those factors could you argue that the bionic leaf could not meet our needs...
  what are you smoking? that's exactly what I said. The actual amount of energy was however many billion gallons per year, the space requried was however many square kilometers. isn't that exactly was I said?
  
  While liquid hydrocarbons are fairly good in terms of specific energy, they are horribly inefficient compared to alternatives. I suppose it's good that you can easily carry that much energy around with you when you will inevitably piss 80% of it away as waste.
  this is a good point.
  
  And I'm pretty sure "god's fuel" would be hydrogen, used in the form of nuclear fusion. That literally powers the universe and is the source of all complex matter that we know of.
  this is also a good point.
21. Re:energy balance doesn't work out by Smidge204 · 2015-02-14 12:46 · Score: 1
  
  first, diesel is maybe 10-15% more energy rich than gasoline.
  Mea culpa - I got KWH confused with BTUs since I'm more used to using BTUs for diesel equivalents. Yes, it's about 15% more.
  
  The actual amount of energy was however many billion gallons per year, the space requried was however many square kilometers. isn't that exactly was I said?
  The closest you come is stating insolation as joules per square meter but at no point did you bring total energy required or total area required in your original post. It took you several hours before someone prompted you to actually go back and do that.
  Basically you only managed to be relevant in hindsight after you got dogpiled.
  =Smidge=
22. Re:energy balance doesn't work out by Noah+Haders · 2015-02-14 13:10 · Score: 1
  
  What dog piled? We had an interesting conversation. In my initial post I estimated the time it would take to make a gallon of gas (a unit of energy) from a square meter of bionic leaf, starting with an estimate of solar insolation (a unit of power density). Looks like an energy equation to me.
Re:That's nothing by Austerity+Empowers · 2015-02-11 06:00 · Score: 1

For that, we'd need a fan...
Re:That's nothing by Anonymous Coward · 2015-02-11 06:15 · Score: 1

When the shit dries, it can be used as fuel.
It can also be thrown all over the porch and doorstep of that asshole neighbor whose dog keeps crapping in your yard. In an area with leash laws.
Frankenfuels by JazzHarper · 2015-02-11 06:15 · Score: 1

Anti-GMO villagers with pitchforks will kill the project.
Re:How does that work, now...? by Crashmarik · 2015-02-11 06:34 · Score: 1

H2 - > 2H+ (2e)
Re:I'd be more impressed... by beelsebob · 2015-02-11 06:57 · Score: 1

That's easy - dehydrate it, then burn it.
Re:That's nothing by nobuddy · 2015-02-11 07:02 · Score: 1

Be happy it is only that much. When I was in Denver they outlawed them entirely and sent animal control around to snatch any they find in a yard and put it down.
Re:That's nothing by davester666 · 2015-02-11 07:18 · Score: 2

And it dries faster when you spread it out everywhere.

--
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Re:How does that work, now...? by Dragonslicer · 2015-02-11 08:26 · Score: 1

An enzyme takes the hydrogen back to protons and electrons...
Isn't that nuclear fission? That must be one hell of an enzyme. I hope the terrorists don't get their hands on it!
The idea that there were electrons in the nucleus of an atom went out of fashion when the neutron was discovered.
No, it's chemistry. by Ungrounded+Lightning · 2015-02-11 09:49 · Score: 2

An enzyme takes the hydrogen back to protons and electrons...
Isn't that nuclear fission?
No, it's chemistry. Specificially, ionization.
Monatomic hydrogen has a single proton (and very occasionally one or two neutrons) for its nucleus, "orbited" by a single electron. Molecular hydrogen has two atoms of hydrogen - two protons bound together into a molecule by sharing their associated electrons in a chemical bond.
Separating the individual nuclei from their chemical bonds (typically dragging along all but one or all but a few of their electrons) is a chemical process, producing a dissolved positive ion. Because hydrogen has a single proton and electon per atom, a positive ion of (non-heavy) hydrogen, missing one electron, is a bare proton.
Now if you wanted to change the number of protons and/or neutrons in the nucleus, change a proton to a neutron or vice-versa, or rearrange a multi-nucleon atom into or out of an excited state (say by adding or releasing a gamma ray), you WOULD be talking nuclear processes. If it cosisted of separating the nucleons of a single nucleus into two groups it would be nuclear fission. But separating the nuclei of different atoms from a molecular bond and/or removing electrons from them, is just chemistry. Energies per operation are measured in single-digit electron volts, rather than kilovolts or higher.

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1. Re:No, it's chemistry. by angel'o'sphere · 2015-02-11 10:14 · Score: 1
  
  No, it's chemistry. Specificially, ionization.
  No it is not.
  An enzyme takes the hydrogen back to protons and electrons...
  This is utter nonsense. An attempt to try 1337 speak perhaps? But cool that you defend its usage and think everyone in the thread who stumbled over that dumb wording is an idiot.
  
  --
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