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Microbes Churn Out Hydrogen at Record Rate

ScuttleMonkey posted more than 6 years ago | from the now-make-stuff-that-uses-hydrogen dept.

Biotech 168

FiReaNGeL writes to mention that Penn State Researchers have improved on their original microbial electrolysis cell design bringing the resulting system up to better than 80 percent efficiency when considering all energy inputs and outputs. "By tweaking their design, improving conditions for the bacteria, and adding a small jolt of electricity, they increased the hydrogen yield to a new record for this type of system. 'We achieved the highest hydrogen yields ever obtained with this approach from different sources of organic matter, such as yields of 91 percent using vinegar (acetic acid) and 68 percent using cellulose,' said Logan. In certain configurations, nearly all of the hydrogen contained in the molecules of source material converted to usable hydrogen gas, an efficiency that could eventually open the door to bacterial hydrogen production on a larger scale."

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BLOCK/BAN THIS ARTICLE (3, Funny)

LiquidCoooled (634315) | more than 6 years ago | (#21342807)

Quick, block and ban this article before the boss sees it.
If he had his way he will fill the water cooler with vinegar to try to increase our productivity.
(If you are working at EA I'm afraid its too late)

Re:BLOCK/BAN THIS ARTICLE (3, Funny)

Penguinshit (591885) | more than 6 years ago | (#21342837)

As long as that vinegar is Chateau Petrus, I'm all for it.

Re:BLOCK/BAN THIS ARTICLE (1)

ozmanjusri (601766) | more than 6 years ago | (#21344911)

(If you are working at EA I'm afraid its too late)

Too late in my office as well, judging by the incredibly high methane levels in the lunch room.

Uhm (3, Interesting)

lorenzino (1130749) | more than 6 years ago | (#21342819)

This reminds me a lot of some Asimov books. So, are we getting there ?

Re:Uhm (1)

SatanicPuppy (611928) | more than 6 years ago | (#21342955)

I sure hope so. Getting this sort of tech as a backyard/rooftop energy generator could be insanely useful. Off the grid for nothing...Hydrogen beats the crap out of batteries as far as energy storage, so high efficiency solar or this sort of biological solution used to produce hydrogen to power your house and your car...Wow. And 80% efficiency is pretty damn good, for a line of research that is still pretty primitive.

A biological system would (probably) be lower setup than a solar system as well, at least given current tech.

Re:Uhm (5, Informative)

Rei (128717) | more than 6 years ago | (#21343321)

Hydrogen beats the crap out of batteries as far as energy storage

Not currently it doesn't. Top-of-the-line hydrogen-powered vehicles are about on par, range-wise, with top-of-the-line lithium-ion powered vehicles (for vehicles released this fall, say, compare a Roadster with an Equinox -- both 200 mile range). But they're notably less thermodynamically efficient and have worse performance. Honda has a prototype FCX that they say will be able to get 350 miles by using an undisclosed storage material, but storage materials always raise issues of their own (such as how much energy it takes to get the hydrogen in and out -- thus hurting the thermodynamic efficiency even more), and if you want to count vehicles that don't exist yet... Of course, if your energy source is hydrogen *to begin with*, sure, hydrogen would be a better choice present-day. We'll have to see how each respective technology advances. Personally, I'd rather we be driving largely on grid power instead of trying to store all our energy on the vehicle ;)

Getting this sort of tech as a backyard/rooftop energy generator could be insanely useful

You want them to eat your roof? You did read the article (or even the summary) and realize that these aren't photosynthetic bacteria, right? That will almost certainly come in the future, but that's not what we're dealing with here.

A biological system would (probably) be lower setup than a solar system as well, at least given current tech.

But maintenance can be very tricky. Bacteria mutate, get attacked, and so on. Plus, you need to keep feeding them and removing waste products. This is certainly viable, present-day, in industrial scale applications, but it probably won't scale down very well any time soon.

I will agree with you on one thing:

Wow. And 80% efficiency is pretty damn good, for a line of research that is still pretty primitive.

It sure is.

Re:Uhm (1)

Cassius Corodes (1084513) | more than 6 years ago | (#21343619)

Bacteria are fairly low maintenance - so the risk form attack is low as they can mutate to defend against the invasion. However as long as you keep feeding them the right stuff they will continuously optimise for the task :) (although depending on their metabolism they may see the production of hydrogen as inefficient way of reproducing themselves and switch to a different by-product that works faster)

Re:Uhm (2, Insightful)

Firethorn (177587) | more than 6 years ago | (#21344189)

although depending on their metabolism they may see the production of hydrogen as inefficient way of reproducing themselves and switch to a different by-product that works faster

That's indeed part of the problem from what I've heard for using bacteria to produce stuff.

Likely any home user would have to 'scrub' his system every so often as non-hydrogen producing bacteria start emerging and taking over. Hopefully the fix would be equivalent as opening a yeast packet for making bread is today.

Still, I don't see home fuel production spreading much further than it has today. It's always going to be a niche market - most people just aren't going to want to go through the hassle, no matter how simple you make it. Plugging in at night is about as far as I'll give them.

Re:Uhm (3, Insightful)

jchernia (590097) | more than 6 years ago | (#21343941)

Keep in mind that septic tanks work on this principle, just drop new tablets of the bacteria in every once in a while and processing resumes, clear water leeches out and there is a ready supply of food for them. Been in use on small scale for a very long time. Composting also works with a constant supply of food on a small scale.

As for eating your roof, there are already bacteria that do that, but they have to be in the belly of a termite to survive, likewise if some of these were to get out, I don't imagine they would last long.

Re:Uhm (2, Funny)

fain0v (257098) | more than 6 years ago | (#21344979)

Bacterial maintenance is really quite easy. I have been maintaining my own methane producing bacteria for decades now.

Re:Uhm (2, Informative)

Fordiman (689627) | more than 6 years ago | (#21344891)

"Hydrogen beats the crap out of batteries as far as energy storage"

That really depends on the drivetrain involved. For example, Natural Gas ICE's, like those used in city busses, top out at 30% Carnot (pretty damned low). Our best HFC electric drivetrain will put out 35% Ideal (higher than 35% Carnot) at high load, but the number of cells needed to effect that kind of output are high (heavier 'engine'). Include the 80% efficiency from generation, and the 25% efficiency hit for making the hydrogen liquid, and you end up with an overall efficiency of around 20% Ideal (still higher than 30% Carnot at ICE temperatures - which is around 6.3% Ideal efficiency).

This is Slavery! (3, Funny)

eln (21727) | more than 6 years ago | (#21342849)

This is absolutely horrible, and I demand it be stopped! These researchers are advocating the mass enslavement of innocent microbes. These microbes will be forced to work nonstop on Hydrogen production from the moment they are born to the moment they are finally literally worked to death. Multiple generations of microbes will toil endlessly in these bacterial concentration camps, with no relief in sight!

We must stop the senseless abuse of microbial rights! We must fight for the smallest and most vulnerable among us! Stop this horror now!

Re:This is Slavery! (0)

Anonymous Coward | more than 6 years ago | (#21342883)

Heh. Cute little blobbies, doing their cute little workhorse activities.

Re:This is Slavery! (1)

Saint_Waldo (541712) | more than 6 years ago | (#21342907)

You must have granted sovereignty to the bacteria in your stomach. If not, you're just another oppressor of our bactobretheren.

Re:This is Slavery! (0)

Anonymous Coward | more than 6 years ago | (#21343875)

If you have bacteria in your stomach I suggest you get to a hospital post haste. They have antibiotics for that now.

Re:This is Slavery! (1)

Eternauta3k (680157) | more than 6 years ago | (#21344215)

In the internet, no one knows you're a cow?

Re:This is Slavery! (1)

ozmanjusri (601766) | more than 6 years ago | (#21345063)

I suggest you get to a hospital post haste.

Maybe.

Hospital staff always enjoy a good laugh, if they're not too busy. http://en.wikipedia.org/wiki/Intestinal_bacteria [wikipedia.org]

Re:This is Slavery! (5, Funny)

Jeremi (14640) | more than 6 years ago | (#21342977)

These microbes will be forced to work nonstop on Hydrogen production from the moment they are born to the moment they are finally literally worked to death


Relax, dude. We've fixed them up with an excellent simulation of their society at the peak of its development. They'll go happily about their simulated lives, and never know they are just sitting in a vat generating power for us.

Re:This is Slavery! (0)

Anonymous Coward | more than 6 years ago | (#21343229)

Well played, sir.

Re:This is Slavery! (1)

h2k1 (661151) | more than 6 years ago | (#21344001)

do you realize that in the precise moment you materialized that thought some of us have been visited by the man in black? are they nanobots dropped inside this petri dish?

Re:This is Slavery! (0)

Anonymous Coward | more than 6 years ago | (#21344439)

... until one of them breaks out and starts a revolution - red pill anyone?

Re:This is Slavery! (1)

pclminion (145572) | more than 6 years ago | (#21342997)

Oh, the humanity! Imagine all the poor little penicillium molds in your bleu cheese, suffering and toiling to no good end. And the wretched yeasts which live in your beer, enslaved to a life of ethanol production. And don't even get me started on the fungal rights issues associated with kombucha tea.

Just wait. (1)

e9th (652576) | more than 6 years ago | (#21343087)

Sure, they'll have it rough for a while. Then they'll form the Organization of Hydrogen Electrolysing Microbes and we'll all be screwed to the wall.

Re:This is Slavery! (1)

ravenwing_np (22379) | more than 6 years ago | (#21343301)

I wonder when we will see people trying to purchase Vegan Hydrogen. Because I could probably sell it for a 2x markup and have a ready made audience.

Re:This is Slavery! (1)

Bloodoflethe (1058166) | more than 6 years ago | (#21343801)

Yes, my brother, we must ensure that the rights of the least among us is not violated. Otherwise, there will be a slippery, bacteria-laden slope that will lead to the worst humano-bacterial oppression the world has ever seen.

Re:This is Slavery! (1)

Null Perception (914562) | more than 6 years ago | (#21345223)

Won't somebody think of the microbes?!

My personal yield... (4, Funny)

Penguinshit (591885) | more than 6 years ago | (#21342873)

I have a high hydrocarbon yield from beer. Does that help?

Cabbage consumption increases yield dramatically!

Re:My personal yield... (1)

Saint_Waldo (541712) | more than 6 years ago | (#21342961)

Hydrogen sulphide doesn't count, stinky.

Re:My personal yield... (1)

KudyardRipling (1063612) | more than 6 years ago | (#21343303)

There are times [BRRRRRRFFFT!] that I think Gazprom might [POOT!] have an interest [FFFFT!] in my [PLLLLITT!] intestinal prokaryotics. Don't flick that light[BOOOM!]

Gas explosion levels complex, details at 11.

288 percent increase over electricity input (3, Informative)

explosivejared (1186049) | more than 6 years ago | (#21342899)

From the PSU Press Release [psu.edu] :

"This process produces 288 percent more energy in hydrogen than the electrical energy that is added to the process," says Logan.

That illustrates just how big the jump in efficiency is here. These bacteria are amazing little energy multipliers. It's quite astonishing!

Re:288 percent increase over electricity input (4, Insightful)

pushing-robot (1037830) | more than 6 years ago | (#21342965)

Yes, but the bacteria are producing it from decaying plant material. You'd have to see how much greenhouse gases are being produced by the bacteria as they decompose the vinegar/cellulose/whatever before calling this a better solution than conventional electrolysis.

Re:288 percent increase over electricity input (5, Informative)

Gregb05 (754217) | more than 6 years ago | (#21343031)

It's 0 sum with how much greenhouse gas is being captured by growing the plant.

The only thing that ISN'T 0-sum would be pulling greenhouse gases out from hundreds of feet underground; Which we already do.

Re:288 percent increase over electricity input (1)

pushing-robot (1037830) | more than 6 years ago | (#21343443)

Plants get carbon from the ground too. In fact, industrialized agriculture has been depleting soil organic carbon for decades from overfertilization and overproduction. If we start mass-producing even more crops to supply our energy needs, we may trade sucking carbon from miles below the ground for carbon inches below the ground, but the problem will remain the same.

Re:288 percent increase over electricity input (1)

hardburn (141468) | more than 6 years ago | (#21343043)

You mean the carbon they had already absorbed?

Stop breathing, you let out CO2 every time you exhale.

Re:288 percent increase over electricity input (2, Funny)

mikael (484) | more than 6 years ago | (#21343061)

What worries me is where all the H20 from the hydrocarbon burning process is ending up, never mind the CO2

Re:288 percent increase over electricity input (5, Funny)

Waffle Iron (339739) | more than 6 years ago | (#21343101)

What worries me is where all the H20 from the hydrocarbon burning process is ending up, never mind the CO2

It's ending up in our lakes, rivers and streams! Why aren't more people focused on this crisis??

What's wrong with the /. moderation system... (1)

$RANDOMLUSER (804576) | more than 6 years ago | (#21344393)

What worries me is where all the H20 from the hydrocarbon burning process is ending up, never mind the CO2
It's ending up in our lakes, rivers and streams! Why aren't more people focused on this crisis??
+1 Informative

Funniest thing I've seen it the last two weeks, hands down. I'm laughing so hard, I'm pissing myself...

Re:288 percent increase over electricity input (5, Insightful)

Angstroem (692547) | more than 6 years ago | (#21343075)

Uhm, but you are aware that the decaying plant material can't give off more CO2 or other Carbon-based greenhouse gases than it originally consisted of. Close cycle and such.

Grow a tree. Burn a tree. No increase in greenhouse gas.

As long as you don't use your conventional gas-powered buzz saw to bring it down and an F350 to haul it to your place...

Re:288 percent increase over electricity input (1)

Eternauta3k (680157) | more than 6 years ago | (#21344213)

Unless said tree was fertilized with oil products

Re:288 percent increase over electricity input (1)

khallow (566160) | more than 6 years ago | (#21344469)

You mean natural gas products.

Re:288 percent increase over electricity input (1)

Eternauta3k (680157) | more than 6 years ago | (#21344861)

excuse me?

petroleum has little to do with fertilizer (2, Informative)

khallow (566160) | more than 6 years ago | (#21344931)

Methane from natural gas is the primary hydrogen source for fixing atmospheric nitrogen to form ammonia. And that in turn is the primary contribution of fossil fuel deposits to fertilizer.

Re:288 percent increase over electricity input (1)

Jimmy_B (129296) | more than 6 years ago | (#21343137)

<blockquote>Yes, but the bacteria are producing it from decaying plant material. You'd have to see how much greenhouse gases are being produced by the bacteria as they decompose the vinegar/cellulose/whatever before calling this a better solution than conventional electrolysis.</blockquote>
Incorrect. The bacteria will release carbon dioxide, yes, but that same carbon was taken out of the air by the plants they're decomposing. Electrolysis doesn't release carbon dioxide per se, but it uses electricity which comes from coal or oil, to produce hydrogen that contains less energy than the oil you had to burn to make it.

Re:288 percent increase over electricity input (1)

Gregb05 (754217) | more than 6 years ago | (#21343343)

but it uses electricity which comes from coal or oil, to produce hydrogen that contains less energy than the oil you had to burn to make it
Actually, TFA states that the process could be self-sustaining (assuming free plants) with respect to electrical output. This isn't 100% electrolysis, I assume they're using the electricty as a sort of catalyst to lower the breaking energy enough that the bacteria can split the fuel efficiently.

Re:288 percent increase over electricity input (1)

pushing-robot (1037830) | more than 6 years ago | (#21343797)

Electrolysis doesn't release carbon dioxide per se, but it uses electricity which comes from coal or oil, to produce hydrogen that contains less energy than the oil you had to burn to make it

I think you miss the point of hydrogen power. As nice as it would be to have vehicles powered by clean, renewable energy, mechanical engineers have thus far been stymied in designing solar plants, wind farms, or hydroelectric dams to fit stock passenger vehicles. Fortunately, other engineers who more frequently "think outside the box" suggested the concept of stored energy. Vehicles could load up at convenient times and travel a substantial distance before returning to refill. Insidiously like gasoline engines - I know. Clean energy could power a electrolysis machine, which converts electricity into hydrogen and oxygen. The hydrogen would be supercooled and put into a vehicle, which would then burn it (combining it with free oxygen to produce easily-trapped water vapor) and produce motive force. It's ingenious and nearly pollution-free.

Greenhouse Gases (0)

Anonymous Coward | more than 6 years ago | (#21343373)

This is now the new Luddite's Battle Cry.

Any advance in technology will be met with demands that the green house gas impact be studied. You though EPA requirements were crazy now? Just wait.

Re:288 percent increase over electricity input (1)

CodyRazor (1108681) | more than 6 years ago | (#21344175)

What about dead people? would that work?

seriously this could actually be a fantastic use for dead bodies after they die instead of the old cremation or clog up the ground with your corpse. Its certainly the most environmentally friendly way. Im not sure how many tons of corpse we dispose of every year but its got to be a lot. Or do we have some nasty bacteria or something that would screw up the system?

Who's powering your generator?

your mother.

Re:288 percent increase over electricity input (1)

Macondo (836066) | more than 6 years ago | (#21343493)

Its amazing how good a few billion years of practice works

A good step... but not carbon neutral. (4, Insightful)

compumike (454538) | more than 6 years ago | (#21342981)

The 80% figure is impressive. But beware of the efficiency numbers they quote. This isn't the full fuel cycle. You've still got to compress and distribute hydrogen, which takes a lot (gases take lots of work to compress). For a vehicle, burning it isn't too efficient maybe 30-40%, and fuel cells aren't quite there yet.

Additionally, with any kind of electrolytically-driven process like this one, there's a HUGE efficiency penalty once you increase the flow rates to be anything substantial. And you need to, because otherwise the amount of hydrogen produced per fuel cell area would be tiny. And then, at that point, you've got the problem of lots of carbon to dispose of. Guess what -- this working microbial fuel cell takes C,H,O in as vinegar or cellulose, and outputs H2 and CO2! Do you really call that 'carbon neutral' as a fuel source? It's still dumping CO2 into the atmosphere, just less of it per Joule of useful energy.

Still, this is a great direction for them to keep going... there are very interesting things you can do with hydrogen, even to extend existing liquid fuel stocks (i.e. crude oil to gasoline) by hydrogenation. (Much cheaper than building lots of fuel cells... but not carbon-neutral.)

--
Educational microcontroller kits for the digital generation. [nerdkits.com]

Re:A good step... but not carbon neutral. (1)

camperdave (969942) | more than 6 years ago | (#21343049)

I would imagine that a certain percentage of the carbon goes into making the next gen of microbes.

Re:A good step... but not carbon neutral. (2, Informative)

Gregb05 (754217) | more than 6 years ago | (#21343057)

Guess what -- this working microbial fuel cell takes C,H,O in as vinegar or cellulose, and outputs H2 and CO2! Do you really call that 'carbon neutral' as a fuel source? It's still dumping CO2 into the atmosphere, just less of it per Joule of useful energy.
Yes, I do call it carbon neutral. The plants take in C02, H20 and E to create vinegar and cellulose, and due to thermodynamics, plants can't create more H20 and C02 than they take in; so by definition it's carbon neutral.

Re:A good step... but not carbon neutral. (1)

timeOday (582209) | more than 6 years ago | (#21343211)

Yes, I do call it carbon neutral. The plants take in C02, H20 and E to create vinegar and cellulose, and due to thermodynamics, plants can't create more H20 and C02 than they take in; so by definition it's carbon neutral.
Exactly, and the quicker we go carbon neutral the better. (Though after burning so many fossil fuels, we're already way behind. What we *really* need is a car that poops carbon bricks we can bury back in the coal mines).

Re:A good step... but not carbon neutral. (1)

roguetrick (1147853) | more than 6 years ago | (#21343483)

As soon as the plants walk up to the vat by themselves, we'll either be good or horribly enslaved by our plant masters.

Re:A good step... but not carbon neutral. (2, Insightful)

HTH NE1 (675604) | more than 6 years ago | (#21343507)

Yes, I do call it carbon neutral. The plants take in CO2, H2O and E to create vinegar and cellulose, and due to thermodynamics, plants can't create more H2O and CO2 than they take in; so by definition it's carbon neutral.
Except that CO2 is now airborne again instead of locked inside the plants, when they could have carried it deep into the soil and become fossil fuels.

By your logic, the planet as a whole is carbon neutral as nothing from the outside is adding carbon. Indeed, putting stuff into orbit and on interplanetary and interstellar probes is carbon negative (the carbon put into the atmosphere from the combustion during launch was already here).

With that mindset, it sounds like the only solutions for a carbon negative process would be to either perfect alchemy or disperse the planet. "Disperse the Earth" would make a nice bumper sticker.

Re:A good step... but not carbon neutral. (1)

hardburn (141468) | more than 6 years ago | (#21343655)

By your logic, the planet as a whole is carbon neutral as nothing from the outside is adding carbon.

The earth is carbon neutral--the laws of thermodynamics make it that way. However, what matters is if the biosphere is carbon neutral. Carbon sequestered deep in the earth isn't part of the biosphere.

Carbon in the atmosphere can be absorbed by other plants, so putting carbon back in the atmosphere that was there already isn't an issue. Absorbing some carbon and burying it would be a good idea, though.

Re:A good step... but not carbon neutral. (1)

HTH NE1 (675604) | more than 6 years ago | (#21343955)

Carbon sequestered deep in the earth isn't part of the biosphere.
Honest if impertinent question: How deep?

How deep do the deepest roots of the tallest trees go? How deep are our deepest natural groundwater sources? I assume we can't just go by a distance straight down from top surface (natural caves in mountains) or sea level (there is life at the bottom of the Mariana Trench).

Re:A good step... but not carbon neutral. (0)

Anonymous Coward | more than 6 years ago | (#21343971)

That's an interesting "interpretation" of the laws of thermodynamics. I don't think they say what you think they say. So it is forbidden by the laws of thermodynamics for a meteorite to add some carbon to the Earth? How does that work?

Re:A good step... but not carbon neutral. (4, Informative)

Surt (22457) | more than 6 years ago | (#21343723)

I believe the tradition is that carbon neutral means into the air in modern times.

When you burn fossil fuels, you release carbon into the air that was not fixed into the fuel in modern times. So you release 'new' carbon into the air. Carbon positive.

When you burn these fuels, you re-release carbon into the air which was fixed in the last year. This is carbon neutral (no change to atmospheric carbon over short time horizon).

If you take some plants that have fixed some carbon and bury them under a continental fold, that's carbon negative.

Re:A good step... but not carbon neutral. (0, Flamebait)

Khyber (864651) | more than 6 years ago | (#21344731)

due to thermodynamics, plants can't create more H20 and C02 than they take in

Considering plants 'INHALE' CO2, they're not going to produce it to begin with. Only us non-plant types produce CO2.

And for fuck's sake - EVERYTHING IS CARBON NEUTRAL. Unless something extraterrestrial smacks into this planet and adds carbon weight to our planet, NOTHING produces more carbon, as it's been here already the whole fucking time. The whole fucking idea is a SCAM - and if you can't see it, you need new glasses. The "Carbon neutral" people need to be skinned alive, because they're only introducing a bullshit muck into the rest of the issues of global preservation. Screw carbon, what about that Radium cloud floating two inches above your head?

Re:A good step... but not carbon neutral. (2, Informative)

hardburn (141468) | more than 6 years ago | (#21343071)

Guess what -- this working microbial fuel cell takes C,H,O in as vinegar or cellulose, and outputs H2 and CO2! Do you really call that 'carbon neutral' as a fuel source?

Yes, because that's what "carbon neutral" means. You only release as much carbon as you took out of the biosphere in the first place. It's not taking carbon that had been sequestered away for millions of years and releasing it over a 100 year timespan.

Of course, it's not 100% efficient, so it's still only a fancy battery. The additional power has to come from somewhere, and hopefully it won't be oil or coal. That said, I think supercapaciters are a more promising form of fancy battery.

Re:A good step... but not carbon neutral. (1)

Erioll (229536) | more than 6 years ago | (#21343439)

Of course, it's not 100% efficient, so it's still only a fancy battery. The additional power has to come from somewhere, and hopefully it won't be oil or coal.
Kind of. A section from the article is enlightening here:

Even with the small amount of electricity applied, the hydrogen ultimately provides more energy as a fuel than the electricity needed to drive the reactor. Incorporating all energy inputs and outputs, the overall efficiency of the vinegar-fueled system is better than 80 percent, far better than the efficiency for generation of the leading alternative fuel, ethanol.

Which is implying that if you throw this hydrogen into a fuel cell as the source of electricity for the process, you still come out far ahead with lots of usable electricity afterwards.

This isn't perpetual energy, as the "ultimate source" of the energy is the plant material, and the sun itself that grew the plants. All that is "outside input" into the cycle is to "get it going" initially, and after that the only "input energy" is from the plant material itself.

But if the article is mis-stating the amount of electricity used, and you actually need more input into it than what you get out from the hydrogen, then this is actually useless. Kind of like how the ethanol production facilities in the USA consume HUGE amounts of coal to turn the corn into ethanol, which kind of defeats the purpose of the process. What this type of thing would do, if it's as efficient as advertised, is that the production facility itself would be "off the grid" with only the plant being the input material, and still having excess hydrogen to sell. This also depends on there being ENOUGH excess hydrogen (after the feedback I mean) that this is economically viable.

Re:A good step... but not carbon neutral. (3, Interesting)

GryMor (88799) | more than 6 years ago | (#21344031)

I wonder what the actual efficiency is if you take into account sequestering the CO2. It should be feasible since you have to sequester the hydrogen anyway and the CO2 is produced in the reactor, that is, fixed infrastructure, rather than in the eventual fuel consuming entity.

Hell, how much net CO2 could you pull out of the atmosphere with an un fertilized acre of land and a reactor thats producing the hydrogen/electricity needed to fuel the entire endeavor? How does it compare to the real efficiency of current solar cells (after taking into account manufacturing costs/outputs)?

Re:A good step... but not carbon neutral. (0)

Anonymous Coward | more than 6 years ago | (#21343081)

Use the leftover carbon. Combine it with hydrogen using the Fischer Tropf process to create methane or liquid fuels. No need to compress or distribute hydrogen, convert it to methane or methanol and distribute that using existing distribution systems. A few nuclear power plants combined with this process could generate reasonably economical fuel for vehicles, aircraft, and heating, replacing fossil fuels. It's carbon neutral as long as all the carbon comes from plant sources and not coal or oil.

Re:A good step... but not carbon neutral. (1)

BlendieOfIndie (1185569) | more than 6 years ago | (#21343083)

They need to engineer the bacteria to consume ammonia. Then our cars could be fueled off of urine. No more fuel transport cost & its carbon neutral!

Re:A good step... but not carbon neutral. (1)

freemywrld (821105) | more than 6 years ago | (#21343611)

And you could kill two birds with one stone during those highway pit stops! Quick, drink more coffee!!

Re:A good step... but not carbon neutral. (1)

timmarhy (659436) | more than 6 years ago | (#21343389)

burning the hydrogen is very efficent, your right about compressing it for transport though. ideally we will have a break through in battery tech in the next 20 years and we can just generate the electricity using large hydro farms. as it stands, none of these renewable fuel sources cut the mustard, but keep at it people i'm sure one of you will have success.

Re:A good step... but not carbon neutral. (1, Interesting)

Anonymous Coward | more than 6 years ago | (#21343489)

Why compress it?...http://www.virginia.edu/uvatoday/newsRelease.php?id=3273

"Most materials today absorb only 7 to 8 percent of hydrogen by weight, and only at cryogenic [extremely low] temperatures. Our materials absorb hydrogen up to 14 percent by weight at room temperature"

Re:A good step... but not carbon neutral. (2, Insightful)

Anonymous Coward | more than 6 years ago | (#21343565)

Well .. better for carbon that was already circulating in the ecosystem to
be emitted as CO2 than for carbon from fossil fuels - that was previous sequestered - to be emitted. This is recirculation of carbon, rather than injection of new supplies..

Re:A good step... but not carbon neutral. (1)

clenhart (452716) | more than 6 years ago | (#21343639)

> this working microbial fuel cell takes C,H,O in as vinegar or cellulose, and outputs H2 and CO2! Do you really call that 'carbon neutral' as a fuel source?

Vinegar and cellulose is made from plants that get CO2 from the air. It's taking CO2 from the air and returning it. Since the CO2 isn't mined and released in the air, it seems OK in my book.

Burn the hydogen onsite (1)

cryfreedomlove (929828) | more than 6 years ago | (#21343871)

Why not just burn the hydogen onsite for electricity generation? Then you don't have to spend energy compressing or moving the hydrogen. Just put the new electricity on the grid. We'll all be driving plug in electric cars before the portable hydrogen economy ever gets going.

Re:Burn the hydogen onsite (1)

Cadallin (863437) | more than 6 years ago | (#21344363)

I think you meant "We'll all be walking and living in dark, unairconditioned caves before the portable hydrogen economy ever gets going"

Re:Burn the hydogen onsite (1)

cryfreedomlove (929828) | more than 6 years ago | (#21344685)

Why do you think that is the case? That sounds very dismal.

Efficiency analysis. (1)

Gibbs-Duhem (1058152) | more than 6 years ago | (#21344753)

Hiya,

I'm fairly experienced with these things, so I figure I'll offer up what it looks like to me in terms of efficiency.

The 80% number is the ratio of the energy contained in the hydrogen gas to the energy contained in the acetic acid plus the energy used in the form of electricity. However, the stated claim that this is more efficient than ethanol is not really justified based on the actual paper (which I read).

While it may well be better than ethanol (most things are), if we calculate out the actual efficiency of conversion between ethanol and hydrogen typically reported in the literature (Kugai and Deluga are the best papers IMO) we get around -165kJ/mol theoretical energy loss per mol of ethanol converted to hydrogen and carbon dioxide. For comparison, ethanol contains about 1145kJ/mol of energy to start with. That gives an efficiency of around 86%.

Of course, the "hidden" (not very well) cost of ethanol is that it takes massive amounts of energy to produce before you get to the stage of conversion into hydrogen. In the end, you get something between -30% and 30% efficiency converting seeds into ethanol (one well-known paper reported an actual energy loss, ignoring the energy from the sun of course, which will always mean an energy loss in conversion). This is not very good. However, this sort of analysis was *not* done in this paper, and wasn't claimed to have been done in the paper. It is very likely that this process is better than ethanol (most things seem to be), but the summary (and press release) are overstating the case, unless there is information they have that wasn't included in the actual paper.

And to clarify, carbon-neutral does not mean it produces zero CO2. It means that all the CO2 produced at one point came from the atmosphere instead of from fossil fuels. As long as the process is net energy positive, you can use the extra energy to fulfil the energy needs of the process, and remove the need for fossil fuels.

Re:A good step... but not carbon neutral. (0)

Anonymous Coward | more than 6 years ago | (#21345137)

Guess what -- this working microbial fuel cell takes C,H,O in as vinegar or cellulose, and outputs H2 and CO2! Do you really call that 'carbon neutral' as a fuel source? It's still dumping CO2 into the atmosphere, just less of it per Joule of useful energy.


The C, H, O (vinegar or cellulose) comes initially from plant material. As the plants grow, they take in CO2 and sunlight, and release O2 to the atmosphere as they make the C, H, O (vinegar or cellulose) in the first place. Later in the cycle, the stored H2 and the previously relesed O2 are recombined to deliver the energy on demand.

So the full fuel cycle actually becomes Sunlight -> stored H2 -> useable energy, with the C, H, O (vinegar or cellulose) and the CO2 and O2 all being simply "working fluids" along the way.

This process is not a CO2 producer. It is not dumping CO2 into the atmosphere overall, any more than it is dumping O2 into the atmospehere. Both gases are merely exchanged in and out as a part of the cycle.

Yes, the process (as in, the whole of the process) is indeed "carbon neutral".

Oh great. (1, Funny)

Anonymous Coward | more than 6 years ago | (#21343001)

Just what we need. An economy powered by bacteria farts.

Re:Oh great. (1)

marcello_dl (667940) | more than 6 years ago | (#21344873)

Instead of rotten dinosaurs and plants.

Microbes make bacteria` (1)

wbtittle (456702) | more than 6 years ago | (#21343017)

Anyone questioning their flippant use of Efficiency. They mix two modes together. The efficiency energy wise and the efficiency molecule wise. We are 91 % efficient at getting the hydrogen out of the mixture, vs we are able to extract 91% of the energy from the Hydrogen we created that we used to create the Vinegar or Cellulose + the energy needed to maintain the bacteria. Hopefully the bacteria maintain themselves and don't start converting me into Hydrogen.

Re:Microbes make bacteria` (1)

Gregb05 (754217) | more than 6 years ago | (#21343107)

Incorporating all energy inputs and outputs, the overall efficiency of the vinegar-fueled system is better than 80 percent, far better than the efficiency for generation of the leading alternative fuel, ethanol

We achieved the highest hydrogen yields ever obtained with this approach from different sources of organic matter, such as yields of 91 percent using vinegar (acetic acid) and 68 percent using cellulose
the summary is misleading. The article clears it up. Sky is blue, water is wet, etc. etc.

What about the CO2 (2, Informative)

Iberian (533067) | more than 6 years ago | (#21343089)

Considering the byproduct is CO2 we would have to come up with a solution to that problem as well. Granted it is better than having CO2 spewed from each tailpipe concetrated at a single powerplant and in theory contained in some way but for what use?

An idea of what do with the CO2 (4, Insightful)

Radon360 (951529) | more than 6 years ago | (#21344353)

Here's one possible solution:

Bubble it into water in which you release into shallow man-made ponds in order to accelerate algae growth. Harvest the resultant algae, squeeze the oil out of it and make biodiesel. Put the leftovers from that into a fermenter and get what amount of ethanol you can from it. Then dump whatever is leftover from that onto fields to decompose and enrich the soil.

Yes, you are eventually liberating the carbon again in multiple paths, but it comes down to whether you want to actually sequester the carbon, or are willing to recycle it through a number of diversified fuels as many times as possible.

Re:What about the CO2 (1)

hibji (966961) | more than 6 years ago | (#21344821)

The point is that the CO2 from this process would come from recently dead organic matter. This is opposed to getting the CO2 from plants which died millions of years ago. This is a carbon neutral process.

In Soviet Russia (5, Funny)

Degrees (220395) | more than 6 years ago | (#21343093)

In America, researchers apply a jolt of electricity to their wastewater bacteria. In Soviet Russia, the brew tases you! Don't Tase me, brew!

Re:In Soviet Russia (0)

Anonymous Coward | more than 6 years ago | (#21343307)

That was, bar none, the world attempt at a Soviet Russia joke I have ever seen in my 4-digit user id life. Also, avoid combining memes, you moron.

Re:In Soviet Russia (1)

Surt (22457) | more than 6 years ago | (#21343789)

That is a fantastic meme mashup, thanks.

Conservation of energy? (3, Funny)

AJWM (19027) | more than 6 years ago | (#21343111)

bringing the resulting system up to better than 80 percent efficiency when considering all energy inputs and outputs. (emphasis added)

So like, dudes, where does that other 20% of the energy go? The Phantom Zone? No, wait, that'd be an energy output too.

Maybe the system just gets heavier.

Re:Conservation of energy? (2, Informative)

Planx_Constant (594897) | more than 6 years ago | (#21344337)

The 20% is lost to the environment as heat, or is unable to be extracted. That's what efficiency means. If they were achieving 100% efficiency, the headline would probably read a little differently.

creators churning out newclear power at the speed (0)

Anonymous Coward | more than 6 years ago | (#21343157)

of right. there is an unlimited supply, & there's never any subscription fee or cover charge. remember to look up at the sky from time to time, & maybe you'll be one of the first to see the big flash. see you there?

Do the compression deep under water (1)

sobolwolf (1084585) | more than 6 years ago | (#21343201)

When there is talk of the difficulty in compressing the hydrogen to store in usable form, could this process not be done deep under the sea where the great pressures would then compress the gas for you? Just a thought...

Oh yeah? (-1, Troll)

Tablizer (95088) | more than 6 years ago | (#21343377)

If I eat certain south american foods, I turn out methane at a record rate. Beat that, little bug!

scared of hydrogen (0)

JimboFBX (1097277) | more than 6 years ago | (#21344017)

Is anyone else as scared as I am about this haste to produce hydrogen gas? Essentially we're turning water into two gasses, one of which isn't heavy enough to stick around in our atmosphere, meaning its lost for good. What happens if you repeat the cycle of:

100% H20 -> 99% H2 + 1% H2 lost
99% H2 + 02 -> 99% H20; 1% H2 lost

an infinite amount of times? You run out of water. You know that gas pretty much always escapes no matter how you store it or transfer it. You just can't be careful enough, especially if your dealing with consumers and uneducated grunt workers.

Water is essential for regulating the temperature of and cooling the planet. Oh yeah, its required for life as well.

To paraphrase a quote from Jurassic Park: You spent so much time and effort thinking of whether you could, you never stopped and thought whether you should.

Re:scared of hydrogen (1)

monkeyengineered (1042116) | more than 6 years ago | (#21344147)

In order to get the energy back out of it you convert it back into water, or if you leave it alone it will do it itself in the atmosphere, if you want to be afraid of loosing a gas, be sad for helium. It mostly non-reactive and too light for our atmosphere, all those helium balloons of the world are loosing helium to space, with little to no replenishment, and none that's effectively used.

Re:scared of hydrogen (2, Informative)

IndustrialComplex (975015) | more than 6 years ago | (#21344687)

Even if we converted 500 million barrels of water per day into pure hydrogen and launched it into space directly it would take over 40 million years before we ran out.

3.26x10^20 gallons of water on earth
divided by
(5.00x10^8 x 42) gallons used per day /365

~42 million.

Not on my list of priorities to worry about.

Re:scared of hydrogen (2, Insightful)

Copid (137416) | more than 6 years ago | (#21344691)

My guess is that we have enough H in our oceans to keep us going for quite a while. If somebody asked me which molecules I'd be happiest "wasting" in the pursuit of energy, I'd probably go for H2O. We have lots of it, as long as whatever we're doing with it also provides us enough energy to efficiently extract it from sea water.

Anybody want to run the numbers to figure out what percentage of our water we'd be losing per year to sustain our current level of energy use assuming the efficiencies quoted in the article and JimboFBX's suggested 1% hydrogen loss?

Re:scared of hydrogen (5, Informative)

aktbar (22510) | more than 6 years ago | (#21344699)

What happens if you repeat the cycle of: {snip}
an infinite amount of times? You run out of water.

There are a few reasons to not worry about this:

(1) The volume of the earths oceans is enough that if we were destroying water in them at the rate at which we burn oil, it would take a few hundred million years to run out. We wouldn't be destroying it at that rate (I would guess, since you can make a lot of hydrogen from just a little water), but even if we were we have a while to figure out a solution.

(2) Hydrogen and ozone react really well -- the hydrogen wouldn't make it out of the atmosphere before it got bound back up as water.

The down side of (2) is that we could damage the ozone layer with leaked hydrogen (http://gcep.stanford.edu/research/factsheets/effects_climate.html [stanford.edu] )

Re:scared of hydrogen (2)

ookabooka (731013) | more than 6 years ago | (#21345025)

I asked my astronomy teacher about this in high school, apparently hydrogen is so reactive that it'll combine with atmospheric O2 before it gets high enough in the atmosphere to escape. Helium on the other hand will eventually leave earth as it has escape velocity at the temperatures at the highest level of the atmosphere.

Re:scared of hydrogen (2, Informative)

StellarFury (1058280) | more than 6 years ago | (#21345135)

RTFA. This process has nothing to do with electrolysis, they're converting cellulose (loads of carbon) and glucose (C6H12O6) into hydrogen. Neither of those are water.

Fuel Cell Bioterrorism (2, Interesting)

Bones3D_mac (324952) | more than 6 years ago | (#21344613)

Just a thought here, but once this system reached a one-to-one ratio with our current fossil-fuel usage, it may only take a single asshat to engineer and deploy a virus capable of crippling an entire country.

Somehow, I doubt a city/state/country-wide quarantine on vehicles (and other devices) using such a system would be a trivial task.

Re:Fuel Cell Bioterrorism (1)

Carbon016 (1129067) | more than 6 years ago | (#21345261)

I assume it would be unlikely the system would be in place in the actual vehicle itself (too slow) - rather, it would be used in the production facilities and hydrogen would be the input fuel.

Ho-Hum (2, Interesting)

TyTheBold (1188529) | more than 6 years ago | (#21345225)

If we can manipulate microbes to produce hydrogen in record amounts, can we manipulate some that take IN CO2 in impacting amounts as well?
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