Can Microalgae Solve Global Fuel and Environmental Challenges?

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Microalgae present a promising solution to global fuel and environmental challenges, capable of producing biodiesel, ethanol, and hydrogen while also remediating waste and CO2. Research initiatives like the BEAM network focus on enhancing microalgal growth and efficiency for commercial biofuel production and environmental applications. Despite potential, there are significant technical and economic hurdles to overcome before microalgae can replace petroleum, although high oil prices may accelerate progress. Algae's ability to thrive on agricultural runoff and its high yield compared to traditional crops make it an attractive alternative. Overall, the discussion emphasizes the dual benefits of algae in energy production and environmental cleanup, highlighting its potential role in a sustainable future.
  • #241
Mark Nicholls: Algae, if the technology is got right, won't compete [for landuse] with food crops such as corn or sugar cane even. And it appears that the resultant biofuels may be more easily used in existing distribution systems and existing engines.
That's a complicated argument, and I think the various biofuel candidates should be plotted on some sort continuum to show competition for food crops. Granted corn is probably the worst offender and algae the least so, but its not all intrinsic. I suspect most algae biofuel will initially at least be grown on land as the sea based plans seem to be more problematic. Then there also the cellulosic crops like switch grass, which don't need the the same kind of land corn needs.
 
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  • #242
Exxon's R&D head said they weighed biofuels by these factors before ending up with algae:
1. Scale. How far can the fuel feasably scale?
2. Technical challenges.
3. Environmental Performance. Land use, water use, CO2 footprint.
4. Economics.

I'd like to see the outcome of that study.
 
  • #243
mheslep said:
The world's largest oil and gas company just http://online.wsj.com/article/SB124757174435338281.html" it is getting into Algae in a big way.


I find that interesting. Synthetic Genomics was founded by Craig Venter of human genome fame. $600 million will buy a lot of algae tanks and processing. In comparison to the other oil and gas firms, Exxon has previously been low profile on alternative energy. A few months ago they announced they're partnering with Electrovaya to make Lithium polymer batteries and now this algae move.

Here they're looking for yields of a fairly conservative 2000 gallons/acre-year. They're also intending to deliver the algae 'crude' directly Exxon responsibility.
http://www.exxonmobil.com/Corporate/energy_climate_con_vehicle_algae.aspx

Edit:
Per the recorded interview, the 3 primary areas of development will be
1. Find best algae strain that is productive and robust in making hydrocarbon
2. Best production system. Looking at all of them: open pond, closed pond, bioreactor.
3. Integrated production system.

This is great news:smile:. I've always wondered if the oil guys would pick up the slack and start investing in an alternately fueled future.
 
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  • #244
mheslep said:
Exxon's R&D head said they weighed biofuels by these factors before ending up with algae:
1. Scale. How far can the fuel feasably scale?
2. Technical challenges.
3. Environmental Performance. Land use, water use, CO2 footprint.
4. Economics.

I'd like to see the outcome of that study.
In theory, it's carbon neutral - algae convert CO2, H2O into more complex compounds of hydrogen and carbon with energy supplied by sunlight and O2 as a by-product - then the resulting fuel is combusted into CO2 and H2O.

Perhaps the goal is to identify the photochemical (basic chlorophyll-based photosynthesis?) process and scale it up to an industrial process. That could make carbon (CO2) capture more feasible/practical in a more or less closed cycle.
 
  • #245
mheslep said:
Then there also the cellulosic crops like switch grass, which don't need the the same kind of land corn needs.

One key difference is that algae can be collected by simply moving the water in which it grows. Other crops must be collected manually, which takes a great deal of energy relative to the yield. Also, with closed algae systems, there is no evapotranspiration. Also, to the best of my knowledge, algae is the most efficient solar converter [for fuel] found in the plant kingdom. At the least, this is stated to be true and I've never seen a counter-example. It is alleged to be true because of the simplicity of algae as compared to other plants used for fuel.

It is nice to see one of the big companies pursuing this. Ultimately, the ideal crop would be salt-water algae because the demand on fresh water would prove prohibitive. This is easy to see by counting hydrogen atoms in the respective molecules of fuel, and water, and then considering the total demand for fuel and [therefore] water. However, it seems to me that closed systems used to produce electrical power might be practical using fresh-water strains because virtually all of the water could be recovered from the combustion process by feeding the exhaust gasses back into the algae beds, which is already being considered for coal plants for CO2 remediation.
 
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  • #246
hmmm... How much of Death Valley lies below sea level? And how much would a canal cost to the Pacific?
Hey! That's almost the same route as the Vegas to L.A. bullet train.

Lets see...
Pump Pacific water and all the L.A. poo into one end of the lake feeding the algae, and at the same time pushing it to the other end of the lake where it's harvested and the slightly saltier water is pumped back to the Pacific.
7800km2 = ~ 2,000,000 acres (wiki...)
yielding 2E10 gallons per year.(10k/acre yr)
@$2/gal diesel that comes to $40 billion dollars in algae oil per yr.

But what is the water to oil ratio?
If it's 10:1, we'll need to be pumping 500,000 gpm 24/7.

Well, I imagine if we're generating 50,000 gallons of fuel oil a minute, we could afford to run a couple of big pumps, not to mention pay for them in about about 10 minutes. :smile:
 
  • #247
Typically, one harvests when the algae-water is about 1% algae by weight [at that point it looks like pea soup!]. If we assume a 50% oil yield by weight, we need about 200 lbs of water for every lb of oil. However, the water consumed is a different matter.
 
  • #248
Astronuc said:
...
Perhaps the goal is to identify the photochemical (basic chlorophyll-based photosynthesis?) process and scale it up to an industrial process. That could make carbon (CO2) capture more feasible/practical in a more or less closed cycle.
That's not the Exxon/SGI goal, but it is an interesting question: Why can't we simply create a large scale chlorophyll based chemical reactor, a big macro vat of green goop sitting in the sun? With out lifting a finger to jog my biology course memories, I believe the answer is something like this: the chlorophyll based photosynthesis process doesn't work at a macro scale because it requires small concentrated 'islands' with lots of surface area per island to allow controlled diffusion of only particular molecules, also know as a 'cell'. Once we've identified that we need cells, there's likely no beating a biological factory using reproduction via DNA for creating cells in large numbers.
 
  • #249
Ivan Seeking said:
Typically, one harvests when the algae-water is about 1% algae by weight [at that point it looks like pea soup!]. If we assume a 50% oil yield by weight, we need about 200 lbs of water for every lb of oil. However, the water consumed is a different matter.
Perhaps that is one of benefits of Venter's claim in this announcement that he has created a strain that directly ejects the lipids into the solution instead of self containing the lipds inside the cell. Once in the solution the lipids should be separable from the water without destroying the crop, that is, the water and algae stays in place while the energy containing lipids are siphoned off.
 
  • #250
OmCheeto said:
hmmm... How much of Death Valley lies below sea level? And how much would a canal cost to the Pacific?
Hey! That's almost the same route as the Vegas to L.A. bullet train.

Lets see...
Pump Pacific water and all the L.A. poo into one end of the lake feeding the algae, and at the same time pushing it to the other end of the lake where it's harvested and the slightly saltier water is pumped back to the Pacific.
7800km2 = ~ 2,000,000 acres (wiki...)
yielding 2E10 gallons per year.(10k/acre yr)
...:
To replace the total world oil production of ~85 mbbl/day w/ a 2000gal/acre-yr process hoped for by Exxon, one needs about one million square miles of algae farm, or collectively 1000 miles on a side, and a very large source of concentrated CO2. That decreases by 10-20% if most of transportation is moved to electric power, and the algae oil is used to make electricity. Difficult, but at least there would never be a 'peak algae' problem.
 
  • #251
mheslep said:
To replace the total world oil production of ~85 mbbl/day w/ a 2000gal/acre-yr process hoped for by Exxon, one needs about one million square miles of algae farm, or collectively 1000 miles on a side, and a very large source of concentrated CO2. That decreases by 10-20% if most of transportation is moved to electric power, and the algae oil is used to make electricity. Difficult, but at least there would never be a 'peak algae' problem.

In closed systems, in principle one doesn't need any CO2 except for the first batch.

2000 gal/acre-yr is a pretty conservative number.
 
  • #252
mheslep said:
To replace the total world oil production of ~85 mbbl/day w/ a 2000gal/acre-yr process hoped for by Exxon, one needs about one million square miles of algae farm, or collectively 1000 miles on a side, and a very large source of concentrated CO2. That decreases by 10-20% if most of transportation is moved to electric power, and the algae oil is used to make electricity. Difficult, but at least there would never be a 'peak algae' problem.

My. That's a big pond.
Divided by the world population, that means everyone needs a 64' x 64' pond.
Still a big pond by my standards.

mheslep said:
Perhaps that is one of benefits of Venter's claim in this announcement that he has created a strain that directly ejects the lipids into the solution instead of self containing the lipds inside the cell. Once in the solution the lipids should be separable from the water without destroying the crop, that is, the water and algae stays in place while the energy containing lipids are siphoned off.

Algae that poops oil? Now why didn't I think of that?
That's as good as my bacteria that eats algae and then farts methane idea, that was thought of 6342 times in the last 6 months by various people. :smile:
 
  • #253
OmCheeto said:
Algae that poops oil? Now why didn't I think of that?
That's as good as my bacteria that eats algae and then farts methane idea, that was thought of 6342 times in the last 6 months by various people. :smile:

Having the idea is the easy part. :wink:
 
  • #254
Ivan Seeking said:
In closed systems, in principle one doesn't need any CO2 except for the first batch.
Eh? Did you mean H2O? If carbon is continuously removed in the form hydrocarbon oils from the closed system, then it must be continuously inserted mole for mole via CO2 or other forms of hydrocarbon.

2000 gal/acre-yr is a pretty conservative number.
Yes, I know you have cited other sources in this thread w/ larger numbers. 2k is Exxon's number.
 
  • #255
mheslep said:
Eh? Did you mean H2O? If carbon is continuously removed in the form hydrocarbon oils from the closed system, then it must be continuously inserted mole for mole via CO2 or other forms of hydrocarbon.

When the oil or biomass is burned, the CO2 is returned to the system in the form of exhaust gasses to be absorbed by the next batch of algae.

In principle we have a closed system with only sunlight going in, and electrical power going out.

Yes, I know you have cited other sources in this thread w/ larger numbers. 2k is Exxon's number.

I know. It is still a conservative number. The aquatic species program obtained yields of 5000 gallons per acre-yr in open ponds, which is probably a practical upper limit. Note that "other sources" are citing ten and even twenty-thousand gallons, and more in some cases, per acre-year. However, simple energy calculations show this [the high numbers] to be impossible. The only exceptions to this may be the approaches that involve the introduction of other energy sources, like sugar, into the system.
 
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  • #256
Ivan Seeking said:
When the oil or biomass is burned, the CO2 is returned to the system in the form of exhaust gasses to be absorbed by the next batch of algae.
Oh that system, the big system, sure.
 
  • #257
mheslep said:
Oh that system, the big system, sure.

Hey, we only think big around here! :biggrin:

To me the idea of using algae for the remediation of coal gasses is a bit ironic considering that we might be able to replace the coal with algae and close the loop.
 
  • #258
mheslep said:
Perhaps that is one of benefits of Venter's claim in this announcement that he has created a strain that directly ejects the lipids into the solution instead of self containing the lipds inside the cell. Once in the solution the lipids should be separable from the water without destroying the crop, that is, the water and algae stays in place while the energy containing lipids are siphoned off.

If true, that is huge because it would not only eliminate the step of separating the algae from the water, but also removing the oil from the algae. Separating oil from water is relatively easy. Also, depending on the doubling time of the algae, it could drastically improve the rate of production per acre. Some of the best oil producers are also slow growing. For example, the "Algae 101" strain, Botryococcus Braunii, which has reportedly been measured at 80% oil by weight in one case, has a doubling rate of something like once every two or three days. Other strains with low oil yields - say 15% oil by weight - can have a doubling rate of one every few hours.

Interestingly, one scientist claims that no matter what strain is considered, the rate of oil production [for good oil producers] is nearly a constant, which may make sense from an energy standpoint. But there is no doubt that growing the stuff from a pure culture is a limiting factor for continuous production.
 
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  • #259
Here's only blurb available on the SGI site regarding the synthetic strain:

Current methods to produce fuel from algae include processes that resemble farming. Algal cells are grown, harvested, and then bioprocessed to recover the lipids from within the cells. In contrast, in one of our solutions, SGI has engineered algal cells to secrete oil in a continuous manner through their cell walls, thus facilitating the production of algal fuels and chemicals in large-scale industrial operations. Our first product in this area is a biocrude to be used as a feedstock in refineries.
http://www.syntheticgenomics.com/what/renewablefuels.html
 
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  • #260
Here's a particularly articulate http://www.xconomy.com/seattle/2008/10/23/vinod-khosla-speaks-at-seattles-algae-biomass-summit/2/" of the state of algae technology and barriers to exploitation from the venture capitalist guru Khosla:

General business model goals for any tech business:
—Relevant cost. Energy technologies are only scalable if they’re competitive without subsidies in places like China and India (what he calls the “Chindia price”)

—A scaling model. The technology’s growth has to be exponential and highly distributed (”we saw this in the Internet,” he says).

—Low adoption risk. “The only thing that solves the carbon-reduction problem in transportation is a liquid fuel-based solution,” he says. Something like hydrogen fuel requires too much development in infrastructure to make it go mainstream.

And algae specifically:
So why hasn’t he invested in algae yet? Khosla first gave his broader “venture rules of investing.” First, a company should “attack manageable but material problems.” Second, its technology should achieve “unsubsidized competitiveness”—which in the case of algae, would be prices competitive with oil prices of around $50 per barrel. Third, the tech has to scale to large numbers of users, and have declining costs with scale. And fourth, it should have “manageable startup costs and short innovation cycles. He pointed out that algae satisfies all of the above (”I can do a new strain of algae in 6 months”), except for the cost competitiveness.

Looking ahead, Khosla said, “To predict the future, invent it. It’s not what it is, it’s what it can be.” He proceeded to give a detailed reality check for algae, in that it is competing with things like biomass methods for producing ethanol and oil. Calculating a theoretical maximum output of 2000 to 6000 gallons of oil per acre per year for algae (based on solar energy availability and current conversion systems), he said, “Algae clearly has the potential to have very high miles driven per acre, but today it’s pretty low.”

Adding up the production costs for algae-based fuels—carbon dioxide, harvesting, containment, and energy, as well as systems to move, mix, and add light to the plants— he concluded, “I think algae can get above biomass in total gallons per acre, but the reason we haven’t invested is we haven’t believed the plans we’ve seen so far meet the [cost] criteria.”

To break through, Khosla advised pursuing “black swans,” technical approaches from outside the realm of traditional experience, with game-changing impact. “The strategy is more at-bats, more shots on goal,” he said. “Most of your approaches will fail, but a few will succeed. You will build from each others’ experience, and get better and better.” The examples of possible black swans he gave were companies like Algenol Biofuels (ethanol-producing algae) and Sapphire (oil-producing algae), and the idea of ocean farming for algae.

As for advice to startups in the space, Khosla said, “Don’t try to get to market quickly with a small improvement. Even a good process isn’t good enough, you have to be truly great to compete. That’s the right vein to build an algae company. I’d say we need to work on more fundamental breakthroughs in algae…Take your time, don’t be in a hurry where you’ll reduce your technical risk, but increase your market risk. Take two more years and do the research. The day you have good fuel out of algae that’s cost-effective, it’ll get into the market.”
 
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  • #261
Obviously Exxon sees it a little differently.
 
  • #262
While there were and are a good number of practical engineering challenges for algae-fuel production, as far as I know, there is one and only one reason why we didn't do this long ago: The price of crude was too low.

When the Aqautic Species Program concluded, http://www.nrel.gov/docs/legosti/fy98/24190.pdf it was estimated that biodiesel from algae might be competitive when diesel was over $2 per gallon. At that time, diesel was about $1 per gallon. Now that the price of crude has a floor near or above the critical threshold for biodiesel to be competitive with petrodiesel, we are seeing a growing interest in viable alternatives to crude oil.

I have yet to see any alternative that offers the range of benefits found in using algae derived biodiesel as our primary energy source. After studying this option for about six months, I began to see that it is truly the elegant solution to our energy problems:

1). Does not need to compete with food crops
2). Does not need to use fresh water
3). Highest energy conversion rate of any plant [with qualifer stated earlier]
4). Greatest yield per acre-yr of any biofuel option
5). About 1.6 times the energy density of ethanol, and as good as gasoline
6). High lubricity of biodiesel allows for more efficient operation of engine [as seen in the Boeing test flight]
7). Diesel engines are about 1.4 times more efficient than internal combustion enginers
8). CO2 neutral
9). Clean diesel cars are already sold in Europe. The Honda diesel gets better mileage than the Honda hybrid. The proof in in the pudding!
10). Compatible with existing energy infrastructure.
11). The conversion to a biofuel economy can be implemented relatively quickly
12). Algae can be used to produce diesel, ethanol, and Hydrogen. So the development of algae technologies could be a stepping stone to a Hydrogen Economy.
13). Having a value of ~ $600 Billion annually - money sent to foreign oil suppliers - a domestic algae program would eliminate at least 60% of the trade deficit [depending on the current price of crude].
14). Can be used to remediate CO2 as well as toxic and other waste products from agriculture, industry, and municipalities.
15). While not necessary, it could be scaled-up to provide 100% of the required energy for the world.
 
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  • #263
Ivan Seeking said:
Obviously Exxon sees it a little differently.
Now. The Khosla speech was last October. Khosla said earlier in that same talk that he'd looked at 100 algae plans, so he clearly recognized the potential, but had yet to find anybody to carry the ball across the finish line, a line he defines clearly. No one else was giving money to Algae either last year. But this summer, we suddenly have the algae bloom of Dow Chemical, Solazyme, etc, and now Exxon/SGI.
 
  • #264
The problem that I saw that led to my own efforts was that far too many people were taking high-tech, high-cost-per-unit-area approaches in the form of exotic bioreactors. In some cases it was nothing more than a scam. In others, the people developing the systems didn't have even a fundamental understanding of the limits on production as determined by the solar energy input. In others, it was impossible to know because the information was proprietary. The bottom line is that the cost per unit area for the bioreactor must be very low. In my own plan, I was driven to a price of less than $1000 per acre with a three-year life for the hardware, in order to be competitive at around $3 per gallon [retail]. But this was for a fresh-water, land-based system, and assumed only traditional methods of production and the known strains of algae at that time. Needless to say, this required some very innovative approaches to bioreactor designs.

I think there is little doubt that closed, batch systems, are the way to go. At the least, we know that contamination problems in open systems are generally prohibitive to that approach. The only exception may be when indiginous and dominant strains are acceptable oil producers. But even then, there is no way to be certain that an existing strain, say in a lake, won't be replaced by another or simply die off. Also, strains can mutate quickly. Apparently there are effectively algae wars in the wild, in which each strain mutates until one has an advantage and displaces the other.

Probably one of the best ideas that we came across was that of using batch bags, if you will, that are suspended in water; say for example, in the ocean. This all but eliminates the problems of temperature regulation and contamination.
 
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  • #265
Ivan Seeking said:
...The bottom line is that the cost per unit area for the bioreactor must be very low. In my own plan, I was driven to a price of less than $1000 per acre with a three-year life for the hardware, in order to be competitive at around $3 per gallon [retail]. But this was for a fresh-water, land-based system, and assumed only traditional methods of production and the known strains of algae at that time. Needless to say, this required some very innovative approaches to bioreactor designs. ...
Yes, needless to say. I can't imagine a material or method of any kind that could enclose an acre for $1000. Perhaps there's something that amortizes out to $1000 per year over its lifetime.
 
  • #266
It is possible, but just barely. It took months to come up with something that might be mangeable. Part of the solution was to recognize the value of innovative land preparation. Would it have worked? It worked well at small scale, but things fell apart [financing] before we got any farther. My best hope for a major investor just went bankrupt due to the economy - he was heavily dependent on the auto industry.

Some designs out there can't even hope to be competitive until the price of fuel reaches $15 to $25 per gallon, retail.

However, if the processing costs can be reduced as in the example you gave [no need for dewatering or oil extraction], the cost per unit area can be increased signficantly. This because there are both high startup costs as well as high operating costs for the processing equipment.

One real advantage to using ocean-based systems, beyond the issue of water, is that the cost of land evaporates!
 
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  • #267
Why not just harvest kelp and other natural occurring algaes in open ocean or tideland areas and process in land based plants. Use solar energy to dry the kelp then process to extract the oils and other combustible components. I grew up in Southern California and saw kelp harvesting all the time. I think they were after Iodine and soda ash, but I'm sure there are a good source of energy products even methane. This would solve the land and water problem.
 
  • #268
PRDan4th said:
... but I'm sure there are a good source of energy products even methane. This would solve the land and water problem.
Why are you sure? Do you have a rough estimate as to how much a mass produced barrel of kelp oil or ethanol would cost to make?
 
  • #269
To the best of my knowledge, as for kelp, there is absolutely no evidence that would work. Also, as stated earlier, most wild algae strains tend to be poor producers of oil. This in turn means that the processing costs [dollars and energy] would be exceedingly high for each gallon of oil. While it may be possible to use wild strains of algae as biomass for the generation of electrical power [burned directly], this has yet to be demonstrated. Only in very rare cases would an indiginous and dominant wild strain be appropriate for oil production.
 
  • #270
About the Exxon numbers: I just noticed in another news release that they claim corn ethanol produces 250 gallons per acre-year. This is almost certainly a net yield - includes the energy required for processing - not the gross yield, which is normally cited as being 400 gallons per acre-year. If we assume the same is true for their number for algae - 2000 gallons per acre-year as a net yield - then that is about what I would expect as well. While I think there is reasonable hope for higher numbers over time, for now, 2000 GPAY net is probably reasonable.

All in all, an order of magnitude better than corn is a good start.
 
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