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Microbes Churn Out Hydrogen at Record Rate
Posted by
ScuttleMonkey
on Tue Nov 13, 2007 06:41 PM
from the now-make-stuff-that-uses-hydrogen dept.
from the now-make-stuff-that-uses-hydrogen dept.
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 (Score:3, Funny)
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 (Score:4, Funny)
Parent
Uhm (Score:3, Interesting)
Re:Uhm (Score:5, Informative)
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.
Parent
Re: (Score:3, Insightful)
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 imagin
Re:Uhm (Score:5, Insightful)
Parent
Re: (Score:3, Insightful)
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 s
This is Slavery! (Score:4, Funny)
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! (Score:5, Funny)
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.
Parent
My personal yield... (Score:5, Funny)
I have a high hydrocarbon yield from beer. Does that help?
Cabbage consumption increases yield dramatically!
288 percent increase over electricity input (Score:3, Informative)
"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 (Score:4, Insightful)
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Re:288 percent increase over electricity input (Score:5, Informative)
The only thing that ISN'T 0-sum would be pulling greenhouse gases out from hundreds of feet underground; Which we already do.
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Re:288 percent increase over electricity input (Score:5, Insightful)
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...
Parent
Re: (Score:3, Funny)
Re:288 percent increase over electricity input (Score:5, Funny)
It's ending up in our lakes, rivers and streams! Why aren't more people focused on this crisis??
Parent
A good step... but not carbon neutral. (Score:4, Insightful)
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: (Score:3, Insightful)
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 negativ
Re:A good step... but not carbon neutral. (Score:5, Informative)
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.
Parent
Re:A good step... but not carbon neutral. (Score:4, Interesting)
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)?
Parent
In Soviet Russia (Score:5, Funny)
Conservation of energy? (Score:4, Funny)
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.
Fuel Cell Bioterrorism (Score:3, Interesting)
Somehow, I doubt a city/state/country-wide quarantine on vehicles (and other devices) using such a system would be a trivial task.
An idea of what do with the CO2 (Score:5, Insightful)
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.
Parent
Re:scared of hydrogen (Score:5, Informative)
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])
Parent