Modified microbes turn carbon dioxide to liquid fuel

Mar 29, 2012
An integrated electromicrobial process to convert CO2 to gasoline substitutes. Image: Han Li

Imagine being able to use electricity to power your car — even if it's not an electric vehicle. Researchers at the UCLA Henry Samueli School of Engineering and Applied Science have for the first time demonstrated a method for converting carbon dioxide into liquid fuel isobutanol using electricity.

Today, electrical energy generated by various methods is still difficult to store efficiently. Chemical batteries, hydraulic pumping and water splitting suffer from low energy-density storage or incompatibility with current transportation infrastructure.

In a study published March 30 in the journal Science, James Liao, UCLA's Ralph M. Parsons Foundation Chair in Chemical Engineering, and his team report a method for storing electrical energy as chemical energy in higher alcohols, which can be used as liquid transportation fuels.

"The current way to store is with lithium ion batteries, in which the density is low, but when you store it in liquid fuel, the density could actually be very high," Liao said. "In addition, we have the potential to use electricity as transportation fuel without needing to change current infrastructure."

Liao and his team genetically engineered a lithoautotrophic microorganism known as Ralstonia eutropha H16 to produce and 3-methyl-1-butanol in an electro-bioreactor using carbon dioxide as the sole carbon source and electricity as the sole energy input.

Photosynthesis is the process of converting light energy to chemical energy and storing it in the bonds of sugar. There are two parts to photosynthesis — a light reaction and a dark reaction. The light reaction converts light energy to chemical energy and must take place in the light. The dark reaction, which converts CO2 to sugar, doesn't directly need light to occur.

"We've been able to separate the light reaction from the dark reaction and instead of using biological photosynthesis, we are using solar panels to convert the sunlight to electrical energy, then to a chemical intermediate, and using that to power fixation to produce the fuel," Liao said. "This method could be more efficient than the biological system."

Liao explained that with biological systems, the plants used require large areas of agricultural land. However, because Liao's method does not require the light and dark reactions to take place together, solar panels, for example, can be built in the desert or on rooftops.

Theoretically, the hydrogen generated by solar electricity can drive CO2 conversion in lithoautotrophic microorganisms engineered to synthesize high-energy density liquid fuels. But the low solubility, low mass-transfer rate and the safety issues surrounding hydrogen limit the efficiency and scalability of such processes. Instead Liao's team found formic acid to be a favorable substitute and efficient energy carrier.

"Instead of using hydrogen, we use formic acid as the intermediary," Liao said. "We use electricity to generate formic acid and then use the formic acid to power the CO2 fixation in bacteria in the dark to produce isobutanol and higher alcohols."

The electrochemical formate production and the biological CO2 fixation and higher alcohol synthesis now open up the possibility of electricity-driven bioconversion of CO2 to a variety of chemicals. In addition, the transformation of formate into liquid fuel will also play an important role in the biomass refinery process, according to Liao.

"We've demonstrated the principle, and now we think we can scale up," he said. "That's our next step."

Explore further: Achieving chemical-free natural cosmetics with the power of enzymes

More information: "Integrated Electromicrobial Conversion of CO2 to Higher Alcohols," by H. Li; D.G. Wernick, Science.

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that_guy
4.6 / 5 (9) Mar 29, 2012
Whether or not this turns out to be a productive method, it is still a very clever take on creating energy and fuel.
Callippo
1.5 / 5 (8) Mar 29, 2012
It's definitely more interesting, than the recent proposal involving expensive iridium - the problem is the yield of the biochemical reactions, because the concentrations of fuel achievable are low and its concentration from water solution will consume most of its energy. In general, the installation cost of solar cells with liquid circulating in it is high and it cannot compete with solid state solar cells.
Doc_aymz
2 / 5 (8) Mar 29, 2012
Its a shame that solar panels take so much energy to make in the first place and most never produce more than they cost to make.

Liquid fuel is definitely the answer - all alternatives for cars, planes and trucks will fail until they are as good as the existing system and infrastructure. Unfortunately Diesel is efficient, energy dense, easy to handle and convenient and its very tough act to beat.
Jeddy_Mctedder
2.1 / 5 (7) Mar 29, 2012
The more we know about formic acid the better "..........formic acid seems to be mentioned in so many research pieces on synthetic fuels. At some point, all this experrtise on firmic acid will come in very handy.
djr
5 / 5 (8) Mar 29, 2012
Its a shame that solar panels take so much energy to make in the first place and most never produce more than they cost to make.
Do you have any sources for that Doc? The ROI on panels is currently 3 - 5 yrs - depending on location http://cleantechn...options/ And the EROI is somewhere around 6 (not the less than one that you suggest).
http://sites.goog...analysis
RealScience
4.2 / 5 (9) Mar 29, 2012
@Doc_aymz - your information is over a decade out of date.
Silicon solar panels now repay the energy used to make them in less than 2 years in most climates, and thin film panels in roughly one year.

@djr - 3-5 years is for silicon panels in New Jersey, which is only a mediocre sun area. Payback is much shorter in California or Arizona, and also with other panel types.
Howhot
5 / 5 (5) Mar 29, 2012
Seems like an interesting concept just when we need to sequester vast gigatons of CO2! If all of the sudden we made are own fuel from the air (and solar) that could make a big dent on the GW issue.
kaasinees
1.9 / 5 (10) Mar 30, 2012
Does not mitigrate vast health issues with burning fuels. But as a more pure and refined fuel it should lighten health issues compared to conventional fuels. Also anything that lightens greenhouse gasses is a plus.
djr
5 / 5 (2) Mar 30, 2012
"Payback is much shorter in California or Arizona" Thanks RealScience - it is good to see the numbers coming down so quickly. Another interesting question that affects the numbers - is the length of time they will be producing. Most panels are warrantied now for 25 years - and I read that some are suggesting they may still be putting out 80 percent of rated value after those 25 years - so could still have many years life left in them - even though not producing at full value. Wonder what the per watt cost will be 25 years from now?
RitchieGuy
1 / 5 (5) Mar 30, 2012
Well, now that they've demonstrated the principle, let's hope that they scale up quite soon. And let's hope that the price of vehicles will fall and the fuel will be cheap enough that everyone can afford them, rather than high-priced vehicles that only the rich can afford.
Quite frankly, I'm tired of smelling gasoline at the pump when I fill up the tank.
antialias_physorg
4.3 / 5 (3) Mar 30, 2012
Its a shame that solar panels take so much energy to make in the first place and most never produce more than they cost to make.

I think your information on that is severly dated. That was the state of affairs 30 years ago. Today monocrystalline silicon solar have an energy payback time of between 1 and 2 years (as an aside: windfarms will pay for their energy cost in 2-6 months).
Seems like an interesting concept just when we need to sequester vast gigatons of CO2!

Unfortunately that CO2 is then againreleased upon burning it in a motor. So this, while great, is not the solution to too much CO2 in the atmosphere.

Certainly a step in the right direction for a mid term solution. Long term we'll want something that is completely clean, though (batteries or hydrogen)
RealScience
1 / 5 (1) Mar 30, 2012
@djr - the energy payback time is dropping almost as fast as the cost, driven both by thinner semiconductor materials and higher efficiencies.

The cost per Watt 25 years from now will be close to zero for the semi-conductor portion of the panel leaving the glass and the metal framing as the dominant module costs, and leaving labor and metal supports as the dominant installation costs.

For utility-scale installations the cost 25 years from now will be ~$0.75/W installed (counting everything but the lawyers). For home-owners the costs are much less clear but should be roughly twice that unless major installation changes are developed.
antialias_physorg
5 / 5 (3) Mar 30, 2012
leaving the glass and the metal framing as the dominant module costs, and leaving labor and metal supports as the dominant installation costs.

Maybe we'll just spraypaint it on (which will bring installation costs considerably down)
Or we'll have it as standard feature in windows or shingles (which will bring the extra installation cost close to zero - the only aditional cost being the hookup to the grid)
You can already buy solar shingles on the market.

Then there's already companies that pay YOU to put up solar on your roof (they get a cut from all the energy you sell to the grid for X number of years).

It seem the cost for having solar could already be negative from the start.
that_guy
1 / 5 (1) Mar 30, 2012
@Real science - Your numbers may be accurate if you could just drop the panel onto your roof with no electric, installation, or inverter.

Also, they *technically* do not pay for themselves if used by utility companies.

I live in AZ, and having researched the issue, there is no option that will pay back in two years, even with the tax rebate.

You're looking at 7-10 years payback if you buy and have it installed (most people do not have knowledge to do the inverter/electrical work).

Also, there's the leasing option, where you realize a smaller amount of savings immediately, and consistently.

There are too many factors involved to give the account the way you did. But point is, they pay for themselves from a consumer point of view.

@Anti-alias - A net zero emission fuel source (Such as sequestering CO2 from the air) is perfectly sustainable. Hy can also be net zero emission, depending on the energy required to make it. Hy would have no benefit in that regard.
RealScience
3 / 5 (4) Mar 30, 2012
@that_guy - I was referring specifically to the energy payback (how long it takes to generate as much energy as was used to mine and purify he ingredient, make the panels, box them, ship them and install them), as commented on by djr.

The economic payback is a different matter. 7-10 years sounds about right for Az, maybe 5 if you do the work yourself.
PaddyL
not rated yet Mar 30, 2012
Interesting, but can process ever become cost effective? The end product is alcohol whose btu content is lower the gas or diesel. With our plethora of crude oil and natural gas this process seems appropriate in the 22d century.

Of course, if CO2 is the raw material, should we be concerned that extracting it from the atmosphere will trigger the next ice age? Are we witnessing the unfolding of the scenario disclosed in the sic-fi thriller, "Fallen Angel".
mrlewish
1 / 5 (2) Mar 30, 2012
Energy payback for solar panels is a near useless measurement. The point of solar panels or any other energy source for that matter is to get the most bang for the buck. ie. the cheapest. If you don't think it's worth is by all means keep on buying that oil and coal.. I'm sure that will last.
RitchieGuy
2.1 / 5 (7) Mar 30, 2012
Interesting, but can process ever become cost effective? The end product is alcohol whose btu content is lower the gas or diesel. With our plethora of crude oil and natural gas this process seems appropriate in the 22d century.

Of course, if CO2 is the raw material, should we be concerned that extracting it from the atmosphere will trigger the next ice age? Are we witnessing the unfolding of the scenario disclosed in the sic-fi thriller, "Fallen Angel".


PaddyL. . . .there will always be plenty of CO2 in the atmosphere. Trees and other plants thrive on it.
And it's replenished by hydrothermal and geothermal vents in volcanoes. I doubt it's possible to run out of it.
antialias_physorg
4.2 / 5 (5) Mar 30, 2012
A net zero emission fuel source (Such as sequestering CO2 from the air) is perfectly sustainable.

That's not sequestration. CO2 sequestration is the removal of CO2 from the atmosphere AND STORAGE.
This removes it and then blows it right back out (which is what plants do, anyhow). It's 'merely' carbon neutral - which is good enough.
Eikka
2 / 5 (7) Mar 30, 2012
There's a gaping flaw in the idea: where to get enough CO2?

There's only 300 ppm of it in the air on average, so you need to cool and compress large volumes of air until the CO2 liquefies out, and this takes staggering amounts of energy.

We need to invent a device that makes the formic acid out of electricity, water and air, in a small form factor so that the process can be decentralized and placed where the CO2 is being released, and it has to be able to turn on and off at a moments notice to utilize the surplus energy from renewable sources.
Eikka
2.4 / 5 (7) Mar 30, 2012
That's not sequestration. CO2 sequestration is the removal of CO2 from the atmosphere AND STORAGE.
This removes it and then blows it right back out (which is what plants do, anyhow). It's 'merely' carbon neutral - which is good enough.


Technically, it is sequestering some CO2 because some amount of it will always remain in the liquid fuel that is being stockpiled for later use.

Same thing with the plants. They sequester the carbon in their bodies, since there are trees and grasses and all that stuff around all the time. This is also the reason why using biomass for energy increases atmospheric CO2 since it speeds up the cycle on the part where the carbon is trapped in the plant.
RealScience
3.4 / 5 (5) Mar 30, 2012
@paddyL - there's plenty of oil for quite a few decades, but it is increasingly shale oil and oil sands that are not easy or cheap to extract. And if we burn the fuel made from the CO2, then the CO2 is 'recycled' and it doesn't change the atmospheric CO2 content (unless we work hard to capture the exhaust).

@Ritchie - we've already added ~35% to the atmosphere's CO2, and we're just getting started. Of course if we 'recycle' the same CO2 it doesn't change the atmosphere's CO2 content (unlike what we are doing today).

Eikka - using power plant exhaust as a starting point greatly reduces the energy needed to capture CO2. And releasing the CO2 for use requires low-grade heat, which solar thermal or some CPV can provide as a by-product.
that_guy
2 / 5 (3) Mar 30, 2012
Unfortunately this turned in to a serious intellectual conversation that basically covered all the points. I have nothing left to say.
Eikka
1 / 5 (4) Mar 30, 2012
Eikka - using power plant exhaust as a starting point greatly reduces the energy needed to capture CO2. And releasing the CO2 for use requires low-grade heat, which solar thermal or some CPV can provide as a by-product.


But aren't you supposed to be getting rid of those powerplants that burn stuff, instead of making them necessary? It doesn't solve the problem, because you then need to find more stuff to burn as the fossil fuels run out.

Burning e.g. biomass to generate CO2 to generate formic acid to make butanol is like a really dumb rube-goldberg machine, because it both destroys nature and increases the atmospheric CO2, and wastes most of the energy by being needlessly complicated.
RealScience
3 / 5 (4) Mar 30, 2012
@Eikka - there will be plenty of power plants spewing CO2 for decades to come. In the short term it will be from coal and natural gas, but in the long term it could be from fuels made from reclaimed CO2.

No one would burn biomass to get CO2 to make formic acid to make butanol.
They might, however, burn biomass to produce electricity and then capture the CO2 to make formic acid to make biofuels for cars, thus getting double duty from the carbon while letting plants scrub the air of CO2 and concentrate it into useable carbon again.
However before too long we should be able to absorb CO2 from the air fairly efficiently, and be able to leave the plants for food or for other species.
mayan
1 / 5 (2) Mar 31, 2012
Any chemists here , I need to make calcium carbide, Al-carbide for ethanol,methanol. Using Ca & C or Al & C also solar heat, give me the output weight of CaC2 or Al2C3 for 100KW solar input/4 hours
RealScience
1 / 5 (2) Mar 31, 2012
@mayan - If you are starting with Ca & C or Al & C, the reaction should be exothermic, liberating rather than absorbing energy.

But pure Al and Pure C and Pure Ca are already efficient carriers of energy in our oxygen-rich environment, so it is thermodynamically kind of cheating to start with them producing methanol or ethanol.

Starting with Al2O3 and C gives you a process for producing aluminum metal (see http://www.osti.g...79.pdf).

However to be CO2-neutral, the process also needs to start with CO2. The best work I've seen on this was at Sandia a few years back using cobalt ferrite rather than carbides, but in principle the same could be done with carbides. Google finds "http://www.wired..../01/S2P" as a starting point.
Lurker2358
1 / 5 (4) Mar 31, 2012
Its a shame that solar panels take so much energy to make in the first place and most never produce more than they cost to make.


God, that's absolute BS.

I've done maths on this any number of times, and solar panels pay for themselves several times in their warranted lifetime, even at an average of half the rated power.

Wind and solar sure as hell make a lot more sense than burning fossil fuels or bio fuels, and then trying to use microbes to clean up the pollution afterwards.

I realize what they're trying to do here is come up with a high density renewable fuel for storing energy for later use, because we still have the battery/fuel transport issue in any solar or wind based energy economy.

Personally, I thought that could be solved by using a trolley line or a rail which would power cars, just like the little electric race cars tracks we all had as kids. It seems simple enough, and doesn't involve some exotic physics to accomplish.
Eikka
1 / 5 (4) Mar 31, 2012
They might, however, burn biomass to produce electricity and then capture the CO2 to make formic acid to make biofuels for cars, thus getting double duty from the carbon while letting plants scrub the air of CO2 and concentrate it into useable carbon again.


Even if the biomass works a second job somewhere else, it's still equivalent to asking us to fuel all our cars and vehicles directly by biomass. There isn't nearly enough biomass to do that. We simply can't grow enough to satisfy a fraction of the demand.

Most of the CO2 has to come from somewhere else.


However before too long we should be able to absorb CO2 from the air fairly efficiently, and be able to leave the plants for food or for other species.


And what if we can't?

Then we're stuck with burning coal for the CO2 and using all our arable land to grow biomass to supplement it.

Just like how we're building windmills now and pretending that future generations will solve the resulting lock-in issues.
antialias_physorg
1 / 5 (1) Mar 31, 2012
However before too long we should be able to absorb CO2 from the air fairly efficiently

What does that even mean "fairly efficiently"? We pumped the CO2 into the air at little efficiency (most motors are less than 33% efficient). So to get the CO2 back out we have to expend AT LEAST three times as much energy as we got from putting it there.
Eikka
1 / 5 (4) Mar 31, 2012


God, that's absolute BS.

I've done maths on this any number of times, and solar panels pay for themselves several times in their warranted lifetime, even at an average of half the rated power.


Then you might consider that the actual average output is typically only 1/10 of the rated power in real world applications. You drop down to half the rated power for the simple fact that half of the time it's night and there is no sunshine, so that's the upper limit for what you can expect from a solar system anyways. Then comes facts like latitude, air mass reductions during different parts of the day, weather, installation and implementation details.

They still pay back though, in most of the cases. It just isn't that simple to calculate.
Eikka
1 / 5 (4) Mar 31, 2012
What does that even mean "fairly efficiently"? We pumped the CO2 into the air at little efficiency (most motors are less than 33% efficient). So to get the CO2 back out we have to expend AT LEAST three times as much energy as we got from putting it there.


That's... not how it works.
The efficiency of the engine has nothing to do with it.

What he means is that in the future we'll develop some new technology that can distill air efficiently, i.e. using very little energy, to recapture the CO2 to make more butanol for fuel. This technology needs to be extremely efficient, or else the process of making butanol for fuel would just be a pointless waste.

The danger is that if we implement the butanol economy and then fail to obtain the unobtainiums, we get locked in to the cheap CO2 sources that make the system work - namely the fossil fuels.

We'll just use slightly less of them, kinda like how every gallon of corn ethanol is figuratively 75% oil.
antialias_physorg
1 / 5 (1) Mar 31, 2012
Well, there is a certain energy balance involved. To make some fuel (e.g. butanol) involving CO2 as a source you have to put the energy in there from some other source, since CO2 of its own accord doesn't supply any. CO2 is the end result of taking (almost) all energy out of a fuel. You can't cheat thermodynamics that way.

Then you burn that fuel at low efficiency and you have to put the power back in. The whole cycle is very inefficient.

However, it DOES have its place in an energy mix. No one is arguing we should go 100% biofuel. (at least I have heard no one in the alternative energy scene ever argue that)

Biofuels will just be one aspect in the mix for those applications where storage/availability is more important than efficiency (e.g. in backup generators for cloudy, windless days) - or where it's dirt cheap to make.

So I see no danger of getting locked into anything, here.
RealScience
1 / 5 (1) Mar 31, 2012
However before too long we should be able to absorb CO2 from the air fairly efficiently

What does that even mean "fairly efficiently"? We pumped the CO2 into the air at little efficiency (most motors are less than 33% efficient). So to get the CO2 back out we have to expend AT LEAST three times as much energy as we got from putting it there.


Even with today's technology absorbing the CO2 out of the air doe not require anywhere near the energy released by oxidizing carbon. And the comment was made in response to running out of readily available CO2.

If we then split the absorbed CO2 to reclaim the carbon, that's what takes more energy than we got from oxidizing the carbon. But that energy can be solar, which is where this conversation started. And the great thing is that the intermittency of solar won't matter for such a process.
Eikka
1 / 5 (3) Mar 31, 2012

Then you burn that fuel at low efficiency and you have to put the power back in. The whole cycle is very inefficient.


You don't have to use the butanol fuel to gather the CO2 for the butanol fuel. That's not what this is about at all, and that would be extremely stupid anyhow.
antialias_physorg
not rated yet Mar 31, 2012

YBut that energy can be solar, which is where this conversation started.

Point being: There are more efficient ways to use the solar or wind than making butanol. Put it in batteries or hydrogen and run electric motors (via fuel cells). Only for those applications where we really need an energy medium that can be stored for really long times (or work at all kinds of temperatures) would butanol make sense. (Backup powerplants, for vehicles in areas where it gets really cold, ... )
But efficiency-wise that's a pretty bad road to go. So it's not going to be the mainstay of alternative energy storage anyhow.

And the comment was made in response to running out of readily available CO2.

That's pretty ludicrous. Why would we run out of CO2? There's no chance of that.
RealScience
1 / 5 (1) Mar 31, 2012
And the comment was made in response to running out of readily available CO2.

That's pretty ludicrous. Why would we run out of CO2? There's no chance of that.


@AP - I didn't make the comment about running out of CO2. I had already said "there will be plenty of power plants spewing CO2 for decades to come", but Eikka said that we'd "need to find more stuff to burn as the fossil fuels ran out". I simply pointed out that we can absorb it from the air if we need CO2. We might also want to absorb CO2 from the air to reduce CO2 levels to reverse warming or reverse ocean acidification.

Regarding "more efficient ways to use solar":
If batteries advance significantly or wireless energy transfer works efficiently, then yes, that is true.
But until those are proven, having a 'liquid sunshine' compatible with our current automotive/petrol infrastructure is worth working on.
pauljpease
5 / 5 (2) Mar 31, 2012
Wow, after reading these comments I'm really starting to believe the studies that find, time and time again, that science education in the US is third rate. I've also taught high school math and science, also confirming that observation. To the person saying that the separation of the liquid fuel from water will use up all the energy...higher alcohols like butanol have low solubility in water so naturally separate, like oil and water. To the person saying that if we use CO2 from the air we will trigger an ice age, this is a carbon NEUTRAL technology, not carbon NEGATIVE, because the fuel will be burned shortly after being made, thus reforming the CO2. But keep on with your simple-minded ignorance of facts, that seems to be the most common approach in the US these days. Edakashun, who need that, we the best cuntry in the wurld!
Lurker2358
1.6 / 5 (5) Apr 01, 2012
You drop down to half the rated power for the simple fact that half of the time it's night and there is no sunshine, so that's the upper limit for what you can expect from a solar system anyways. Then comes facts like latitude, air mass reductions during different parts of the day, weather, installation and implementation details.


I already took all that into consideration.

What the hell? Do you think I'm some sort of moron or something? Anybody knows you don't get 24 hours power from solar PV.
Lurker2358
1.8 / 5 (5) Apr 01, 2012
I was just watching "How it's made," or something, on the History Channel yesterday, and the topic was Ethanol.

On their video, they claimed it requires 1 gallon of fossil fuels equivalent to make just 1.3 gallons of Ethanol, not even counting the labor costs, transport costs, and other materials costs of the process.

As you can see, that is only about a 30% net energy gain in the entire process, and I doubt the value of the difference pays for the other costs. Which is the real reason gasoline prices keep rising higher and higher in spite of oil having dropped off a bit and then plateaued near $108 per barrel.

Until somebody comes up with a cellulose method to use the entire corn stalk, or else a more efficient ethanol fuel crop, I don't see how biofuels will ever play a real role in our energy.

The existing processes are probably costing nearly double their net value and pollution by the time you take everything into consideration, yet we ignorantly, blindly charge forward.
ACW
5 / 5 (1) Apr 01, 2012
@Lurker--as far as efficiency is concerned, Algae cannot be beat as it produces between 3-20 times the next best option (corn is much further down the list).
@Eikka--since several industrial processes produce CO2 in abundance, it can be harnessed at the source--even before it is produced as a by-product after the fuel is burned.
Egleton
1 / 5 (4) Apr 02, 2012
Well done everyone. Nice polite thread.
The CO2 could be captured in the Antarctica. I believe that it gets cold enough there to freeze.
packrat
1 / 5 (4) Apr 03, 2012
One possible way to use solar would be to dual Stirling engines with one running off the sun's heat driving the other one to make liquefied air. You could distill the co2 that way. I have no idea how efficient it would be or how much it would end up costing but it would work.
RealScience
1 / 5 (1) Apr 03, 2012
@Egleton - While the record low temperature in Antarctica would solidify CO2 with about 10C to spare, the colder areas are at high altitude (~3500 meters) and are thus at the lower pressure, so conditions for naturally freezing CO2 would be extremely rare even in Antarctica.

Cold temperatures would make the refrigeration process much more efficient, but whether that would be enough to overcome the logistical challenges of finding/bringing energy to run the process in Antarctica and then hauling the CO2 elsewhere for storage is not a given.
jselin
1 / 5 (1) Apr 04, 2012
If you sent a variable fraction of the organics formed into plastic manufacturing you could manage atmospheric CO2 levels at the same time. Maybe create a lumber substitute? I wonder if the costs could be made favorable...
Howhot
5 / 5 (1) Apr 05, 2012
This looks like a potentially very important technology that should be fast tracked and scaled up. But it has to happen fast; with in 10 years or peak oil panic will take over and development won't happen.