Slashdot Mirror
Scientists Use Microbes to Produce Hydrogen
An anonymous reader writes " Environmental engineers at Penn State University and a research scientist at Ion Power Inc. have created an electrically-assisted microbial fuel cell that can be used to produce hydrogen from organic material. The amount of electricity needed for the process is less than the amount required to power a standard cell phone. This advancement can be used to produce hydrogen as a byproduct of water treatment. " Coverage at ScienceDaily as well.
The amount of electricity needed for the process is less than the amount required to power a standard cell phone.
To power what? A 100-gallon microbial fuel cell or a very teensy one?
"A door is what a dog is perpetually on the wrong side of" - Ogden Nash
- One hundred thousand megatons of hydrogen are produced by less energy than is required to power a cell phone for one nanosecond.
- One molecule of hydrogen is produced by less energy than is required to power a cell phone from the moment it is activated with a completely charged battery until the moment it shuts off because its battery becomes completely discharged.
This is what I love about Slashdot articles.Will people be able to buy microbe tanks to generate hydrogen for their own homes? Imagine every home in the world adding to the hydrogen generating infrastructure. All of a sudden fuel cell cars would be a viable venture. Want wheels? Just add sea monkeys!
And what does that say? Nothing. I'm pretty sure I can create a couple of hydrogen molecules with that amount of electricity too and I won't even need any bacteria in the process.
Here's a more useful bit from the article, though it would be even more useful if they would just say what fraction of energy this process requires:
Did the Volt turned into a unit of power while I was sleeping? And I thought I did well in physics.
Tharkban (It is a signature after all)
The less than the amount required to power a standard cell phone statement is totally meaningless because it gives no indication of the efficiency of the process. Even at "0.25V", if the process requires tens or hundreds of electrons per molecule of hydrogen, then the process may be horribly inefficient. Even the "produces four times more hydrogen than would be typically generated by fermentation alone" is meaning less without some facts such as the molar conversion efficiency -- how many moles of hydrogen per mole of acetate does the augmented process create?
Moreover, this process is not the holy grail of pure electrolysis (e.g., splitting water into hydrogen and oxygen), it is an electrolyticly augmented chemical conversion of carbohydrates into carbon dioxide (green house gas), water, and hydrogen. In theory, this process could by part of a biomass-to-hydrogen fuel generation cycle, but as we have seen with ethanol production, the amount ethanol-based energy harvested is poor in comparison with the energy required to grow, reap, and process the plants (corn).
Don't get me wrong, this is a very intriguing finding, but there is far too little information in the article to determine if this process is thermodynamically better or worse than simply burning the carbohydrates in a furnace or standard combustion engine.
What frustrates and saddens me is that the analysis needed to make useful statements about this discovery are not that hard to make. Any competent chemist or chemical engineer could provide a useful back-of-the-envelop estimate of the energy inputs and outputs given an afternoon with the raw data from the experimenters. Either the scientists involved did not do this analysis (shame on them) or the journalists chose to ignore key results (shame on them) or the actual return on energy input is very poor indeed (to bad for all of us).
I hate articles that quote meaningless comparisons and leave the true question of practically total unanswered while holding out a vaporous promise that our energy problems are solved.
Two wrongs don't make a right, but three lefts do.
Of course I didn't RTFA, but if them lil microbe things are breaking off the hydrogen the carbon is going to have to go somewhere.... unless they're bonding it into a solid carbon form (diamonds or graphite or such) then it's going to be into CO2 or similar. Not exactly a huge leap forward in environmental friendliness.
Engineering is the art of compromise.
Rather than buying it and making money on it?
Why would they do that?
Oil companies could care less if they sell oil, Hydogen, ethanol, fuzzy dice, bottled farts or any other energy source. Their goal is to make money. If this is more efficent at making them money they'll jump on it.
But they are happy enough at the moment because the cheapest most efficient ways to make hydrogen use Fossil Fuels.
Once someone finds a more efficient cheaper way to make hydrogen everyone will jump on it, incluiding the oil comapnies.
Totally missing from the article, and the abstract:
Does the process produce as much fuel as is necessary to fuel the process? More? Less?
What's that you say? The article cleary states that this process is cheaper than the old process?
Great! But is it cheap *enough*?
Any sufficiently well-organized community is indistinguishable from Government.