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Mutant Algae to Fuel Cars of Tomorrow?
Posted by
Zonk
on Sat Sep 29, 2007 04:17 AM
from the how-fuel-efficient-is-it-when-they-eat-your-face dept.
from the how-fuel-efficient-is-it-when-they-eat-your-face dept.
Hugh Pickens writes "Algae has long been known as a promising source of biodiesel. It's worth noting, though, that algae also produces a small amount of hydrogen during photosynthesis. The MIT Technology Review reports that researchers have created a mutant algae that makes better use of sunlight to increase the amount of hydrogen that the algae produce. Anastasios Melis and his team at the University of California have manipulated the genes that control the amount of chlorophyll in the algae's chloroplasts. Although the process is still at least five years from being used for hydrogen generation, Melis estimates that if 50% of the algae's photosynthesis could be directed toward hydrogen production, an acre could produce 40 kilograms of hydrogen per day. At the price of $2.80 a kilogram, hydrogen could compete with gasoline, since a kilogram of hydrogen is equivalent in energy to a gallon of gasoline."
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Feasible (Score:5, Informative)
Re:Feasible (Score:5, Insightful)
Just imagine the effect on world politics if nobody cared who had control of the petroleum in the middle east, because it was selling for $4/bbl.
-jcr
Parent
transition (Score:2, Interesting)
Re:transition (Score:4, Interesting)
Well that's not entirely true, Brazil didn't forget. But then again, they don't have corn lobbyists.
Parent
Re:transition (Score:5, Insightful)
1. grow the corn,
2. grow the beets,
3. press out the oils out of the corn for food use,
4. reclaim the used food stuff oils aned animal fats for biodiesel,
5 extract the sugars from the corn, feed the distiller's dried grain and roughage back to the cows (makes food and animal fat for step 4)
6. add beet sugar to the corn sugar and make Butanol [wikipedia.org] instead of inefficient Ethanol
7. profit!
I don't think there will ever be a one answer answer; the answer will be multi-use feed the waste of one almost economical process to the next almost economical process.
Parent
Re: (Score:3, Informative)
Re: (Score:2, Insightful)
Granted, there's an issue of oxygen removal from the water and disrupting the balance of an already stressed environment, but if it was done in largely dead ocean areas, this shouldn't be too much of a problem.
Now if
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Re: (Score:3, Informative)
Also I may be wrong, but I believe you'd still run into oxygen depletion in the ocean, though not directly from the algae. An algal bloom http://en.wikipedia.org/wiki/Algal_bloom [wikipedia.org] increases the amount of bacteria present to 'eat' the algae. These bacteria use the oxygen dissolved in the water, and eventually mo
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Re:Feasible (Score:5, Insightful)
Instead of thinking entirely in terms of big honking swaths of farmland covered in algae, think of 5 or 6 vertical tanks in every backyard, producing ~4kg of hydrogen a day. That would cover automotive energy needs for the average person, probably with some left over.
Also, while farming this stuff right in the ocean wouldn't make much sense, floating farms would be practical, and a good use of space.
I'm a big fan of the idea of using the kind of space that we already waste for energy production (e.g the tops of every wal-mart in america covered in solar cells). Even a land efficient method like this one could benefit from using parts of land that we already use for another, non-conflicting, purpose.
Parent
Re: (Score:3, Insightful)
Can you get enough sun light and CO2? (Score:3)
Can you get enough sun light and CO2 in your backyard?
Assuming you have 10 square meters yard, the sun shine's energy input is 1000W per square meter, you get 10 hours of sun shine per day, then you have 100,000Wh energy input. Assume 10% photosynthesis energy convert efficiency (this assumption is too high, 1%-5% is better but for the ease of calculation, I will use 10%), you will get 10,000Wh energy into hydrogen, that's 36MJ.
One kilogram of hydrogen has 143MJ of energy. Then to produce 1kg of hydro
Re:Feasible (Score:4, Informative)
Parent
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Re: (Score:3, Interesting)
There's another bonus with oil producing algae, it can grow in brackish water and eat sewage [unh.edu].
What algae lacks is a powerful lobby in Washington like the corporate farms and corn sweetener have. It would also threaten a large volume of the petroleum supply chain. Since so much of our foreign policy seems centered around protecting Saudi Arabia's cash flow (when we're not arming Israel), I can't imagine our government getting behind algae production.
Not like energy independence should be a national stra
Nice work, but... (Score:4, Interesting)
Something I find rather more promising is the work described in an earlier MIT review article, where bacteria are being modified to make gasoline directly. [technologyreview.com] Just like petroleum-based gasoline, except that it's carbon-neutral, and sulphur-free. We're talking gasoline from anything that E. coli can ferment.
-jcr
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So many problems to solve? Yes. But chalking one off the list is a good thing, reducing the fundamental problem with hydrogen power - the fact that the variable cost was so high. If there's an abundant energy ri
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Is it to much to ask (Score:3, Interesting)
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Wikipedia requires some basic understanding (Score:3, Insightful)
Persistent opinions ARE accurate opinions in many fields (to the best of human knowledge), and in other fields they're not.
The only strong "limitation" of Wikipedia's model is that it requires readers to understand which field falls into which category. If you wish to accuse Wikipedia of not being 100% useful to totally non-perceptive readers, then yes you're right, one would have to agree with you. It's only useful to totally non-p
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"The types of fields in which persistent opinions are accurate opinions are those ruled by verifiable fact, the rule of mathematics and logic, and cooperative progress through explicit reasoning, not through debate. That includes mathematics and logic themselves, plus all the hard sciences and branches of engineering."
No, beliefs in the hard sciences are not ruled by verifiable fact, at least not when you get beyond the very basics. Most of science is based on hypotheses and theories. One cannot verify
Re: (Score:2, Interesting)
Um, the hard sciences *are* the very basics because they're directly verifiable.
Which is why string theory isn't science.
If by "verify", you mean, "we can't go back in time to witness it", yes.
H2 Panacea (Score:2, Interesting)
Re: (Score:3, Interesting)
Once it's produced, how do you store it? I confess that I now (sort of) work for evil "big oil" but I do have some experience with the practicalities of storing and transporting hydrogen.
Thats a pretty good question there! I'd recommend using Metastable Metallic Hydrogen [wikipedia.org] personally, except there's a small issue that nobody has exactly figured out how to make the stuff yet.
That being said, I always thought that good old Ammonia (NH4) had some nice potential for hydrogen storage. Its easily liquefied at
The requirements... (Score:4, Insightful)
If "a kilogram of hydrogen is equivalent in energy to a gallon of gasoline" then, estimating [howstuffworks.com] about 400 million gallons of gas per day used by the US, we will need 10 million acres of algae farm. That is with the assumption that they obtain their optimal output, and no additional energy is expended for processing, transport, etc.
By contrast, an average nuclear power plant produces 1000 megawatts of energy. Also assuming optimum efficiency, we get (10^9 joules pers second * (60 * 60 *24) seconds per day / (237.1*10^3 joules to electrolyze 1 mole of hydrogen at 298K) * 1.01 grams/mole = 368,047 kilograms of hydrogen per day.
So... 10 nuclear plants, or 10 million acres of algae farm?
Let's not forget that your algae farm will stop photosynthesizing when it's cloudy out.
Re:The requirements... (Score:4, Interesting)
You are right on one thing though - probably better to just generate & use electricity directly than to mess about with Hydrogen, etc. Think of all the plastic/glass you would need to contain the algea and collect the gas..
Parent
Re: (Score:3, Informative)
Nuclear + Hydrogen + Batteries (Score:2)
My tech is better! (Score:3, Funny)
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Omits depth of shit considerations (Score:3, Insightful)
same question (Score:2)
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If this actually turns out to be viable... (Score:2, Interesting)
a. stifle it while there's still fossil fuels to be had (ie with prohibitive taxation)
b. stifle the technology which utilises it (by classifying it for military use)
c. bud off private concerns (or use existing military contractors) who then go on a patent grab for said technology, making an example of anyone who tried it (yes, you, Mr. Hobbyist!)
d. license favoured concerns to (under)develop and (under)utilise the technology until such time as
Chlamydomonas (Score:3, Interesting)
These little fellas are tough. Give them a few basic nutrients (phosphates, trace minerals) sunlight and air and they will grow like weeds. They can be autotrophic (using light) or heterotrophic if you give them a carbon source (like those found in sewage and agricultural waste). People have also had great success growing these by bubbling the exhaust from incinerators through liquid cultures (exhaust is rich in CO2 and NOx which Chlamy can use). Chlamy has been extensively studied (the genome of C. reinhardtii has been sequenced) and there is a huge library of mutants already available. I saw a presentation at an algae conference last year by people working on this. Holy grail is getting hydrogen while they are growing, then extract oil.
Best of all, they are completely harmless (trust me, if they were in any way dangerous I would be dead by now).
Algal biodiesel and butanol from agricultural waste are our best hope. Ethanol from food crops is basically a big give-away to agribusiness companies. While hydrogen is promising, biologically derived liquid hydrocarbons can take advantage of the extensive infrastructure that has been built for petroleum fuels.
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Solar cells, or a combination of mirrors and sterling engines, will probably always beat out organisms for pure efficiency. Doesn't mean we don't also
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So, the middle east could still be a major fuel-producing region, even when it's no longer worth the cost to pump petroleum out of the ground?
-jcr
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Why go all that distance? The US at least has no shortage of sunny desert, and coastal access to two oceans. Either land or sea based biofuel production would be feasible. And after Iraq, I think an increasing number of Americans will want energy independence. Why import fungible goods you can make cheaply and locally? Particularly if the countries exporting said goods are a long way from friendly?
I think the only countries that would actually need fuel imports, if biofuel wor
Re: (Score:3, Insightful)
A major reason why this won't ever be as economical as biodiesel production is that this requires mutant algae, as you said. This means the culture needs to be kept isolated from the outside world to keep it pure (the mutants have reduced fitness compared to wildtype algae).
Biodiesel, on the other hand, is produced by wildtype algae that are capable of holding their own against competing organisms.
If I had more time, I'd dig up photos of t
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Re: (Score:3, Interesting)
What I can't seem to get anyone to explain is why we want a hydrogen economy anyway. Liquid fuel for vehicles seems like a much better plan. The only reason to go hydrogen is if you want to fuel vehicles with coal or nuclear plants, and even then, I think it is a better plan to con
Re:Give me figures. (Score:5, Insightful)
Look, carbon that's locked away underground in the form of fossil fuels isn't part of the carbon cycle. It's been sequestered by geological processes for millions of years, removing it from the air. When we dig it up and burn it, we bring it back into circulation. The total amount of airborne carbon increases; the greenhouse effect gets stronger. This is, in a nutshell, anthropic global warming.
Carbon that's already in the atmosphere can be trapped by photosynthesis. If the plant that trapped the carbon is then burned, or eaten, or even if it just dies and rots, the carbon returns to the air. This is the regular carbon cycle, with or without human intervention, and it doesn't alter the net balance of Co2. It's this process that we employ when we make biodiesel.
Biodiesel doesn't contribute to global warming. At all. The "bio" part means the hydrocarbons were synthesized from plant matter; the carbon in those hydrocarbons came from airborne Co2. As long as you plant biofuel crops, process them, and burn them, the total amount of airborne Co2 will never increase. Every ounce of carbon added to the air is matched by an ounce of carbon removed from the air by the fuel plantation.
Parent
True but needs a little refining (Score:3, Insightful)
This ceases to be true when biofuels become totally self sufficient. This means that fertiliser plants, the plants that manufacture everything used in the biofuel production cycle, stora
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This is true if and only if you don't chop down a bunch of trees in order to make room for
Re: (Score:3, Interesting)
First you have to look at the carbon used to make the biofuels - some will be used for fertiliser, tractors, transport, etc.
Biodiesel production is cheap, easy, spontaneous, and produces no harmful waste. If your starting source is lipids from algae (as GP was talking about) then you need no fertilizer or tractors. And to be honest, you're transporting fuel. Transport isn't carbon input, it just decreases the net yield a bit because you use some of the fuel to transport the rest.
Also if you are using plant matter that currently is being left to rot back into to the soil, (as proposed) then you are burning carbon that would otherwise be sequestrated - and stripping the soil of natural nutrients - and so on.
Plant matter that rots back into the soil releases it's carbon into the aptmosphere through the rotting process. It actually takes very special ci
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You need a unit for time as well.
But the article did have kilograms of hydrogen per acre per day. If we accept the assertion that 1kg of H2 is roughly equivalent to 1 gallon of gas (for automotive use), you are really only some very simple arithmetic away from a fair comparison with gas.
As for water usage, the algae live _in_ the water, not on the ground, so the water will be enclosed, probably in transparent pipes or covered pools. There would be no evaporation, and
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You may be thinking of Jeff Wayne's Musical Version of The War of the Worlds [wikipedia.org], and specifically the section of it about the red weed [wikipedia.org].