Guest post by John Goetz
I keep an active watch of the news for progress being made in the areas of renewable and alternative energy sources. One area that has caught my eye is algal fuel (biofuel produced by algae). One company that has been in the news lately is Sapphire Energy, which claims to be able to produce ASTM compliant 91-octane biogasoline. Sapphire Energy says their technology “requires only sunlight, CO2 and non-potable water – and can be produced at massive scale on non-arable land”.
I am not trying to pick on any one solution or Sapphire Energy in particular. I simply wondered how massive a scale of CO2 and non-arable land is needed to make a noticeable dent in our gasoline demand.
First, how much CO2 do we need? The IPCC guidelines for calculating emissions require that an oxidation factor of 0.99 be applied to gasoline’s carbon content to account for a small portion of the fuel that is not oxidized into CO2. To calculate the CO2 emissions from a gallon of fuel, the carbon emissions are multiplied by the ratio of the molecular weight of CO2 to the molecular weight of carbon, or 44/12. Thus, the IPCC says the CO2 emissions from a gallon of gasoline = 2,421 grams x 0.99 x (44/12) = 8,788 grams = 8.8 kg/gallon = 19.4 pounds/gallon.
Now let’s assume Sapphire Energy simply reverses the process and consumes the CO2 to produce gasoline. In other words, we take 19.4 pounds of CO2 out of the atmosphere for every gallon of gasoline we produce. This seems like is a nice “carbon neutral” process.
What is the cubic volume of atmosphere required to make 1 gallon of gas? Let’s assume for the moment an efficiency factor of 100%, meaning our process will consume 100% of the atmospheric CO2 it is fed. This is unrealistic, but it is unrealistic on the “optimistic” side. According to the EPA, one cubic meter of CO2 gas weighs 0.2294 lbs. At an atmospheric concentration level of 385ppm, one cubic meter of atmosphere contains 0.000088319 lbs of CO2. Thus, 19.4 / .000088319 = 219658 cubic meters (yes, I am ignoring the atmospheric density gradient as one moves from the ground upward, but hang with me). This equates to roughly 4553 gallons of gasoline per cubic kilometer of air.
According to the US Energy Information Administration, US gasoline consumption is currently averaging (4-week rolling) 9.027 million barrels of gasoline per day, or about 379 million gallons (42 gallons per barrel). Thus, to completely replace US gasoline consumption, Sapphire Energy would need to “scrub”, at 100% efficiency, just over 83000 cubic kilometers of air per day. Certainly there is plenty of air available – this volume represents less than 0.02% of the volume of air in the first 1 km of atmosphere. Nevertheless, it is an enormous amount to process each day.
Of course, Sapphire Energy’s near-term goals are much more modest. As CEO Jason Pyle told Biomass Magazine, “the company is currently deploying a three-year pilot process with the goal of opening a 153 MMgy (10,000 barrel per day) production facility by 2011 at a site yet to be determined.” Using my fuzzy math above, that equates to a minimum of 92 cubic kilometers of air a day. Still seems like a lot.
So where will all of the CO2 come from?
Presumably the answer is coal-fired power plants. But let’s see if that makes sense. According to Science Daily, the top twelve CO2-emitting power plants in the US have total emissions of 236.8 million tons annually, or 1.3 billion pounds per day. Now, if that can be converted completely to gasoline, it would amount to 67 million gallons per day, or roughly 1/6 of the daily gasoline consumption.
(Science Daily refers to the twelve as the “dirty dozen,” which I found somewhat humorous given that CO2 is colorless and odorless, and is presumably needed to sustain some forms of life. But then again, so is dirt.)
Sounds great, except that a lot of land is needed to grow all that algae. According to Wikipedia, between 5,000 and 20,000 gallons of biodiesel can be produced per acre from algae per year. Assume for the moment that biogasoline can be produced at the same rate per acre. If we attempted to produce 67 million gallons of gasoline from our “dirty-dozen” every day, we would need between 1.2M and 4.9M acres of land to do this on. The low-end of the scale puts the area needed at more than that of Rhode Island. The high-end adds in Connecticut.
I kind of doubt there is that much land around each of the dirty dozen facilities. This means the gas would have to be sent by pipeline to a giant algae field. Given our ability to pipe oil and natural gas all over the place, sending CO2 across the country via pipeline is probably doable. There may also be plenty of unused or abandoned land (think abandoned oil fields) available to produce the gasoline. Nevertheless, the production scale and transportation logistics required to make this a viable alternative do indeed look massive.
So while the technology holds promise at the micro-scale, it remains to be seen what can actually be done at a scale that matters.
Talk among yourselves.
“hot water for the hoes”
Now that should sell a lot of solar! Excellent.
If it really works why don’t they just stop talking and start producing the stuff and getting rich?
Because it takes money to get started, and PR helps attract money.
You know, I think a useful summary of this discussion is that it sounds more feasible than at first glance: the back of envelope numbers are moving in the right direction, and the technical details seem to be coming together.
One thing, though, is to observe the whole land area issue is not a difficult one. Sure, it’s the size of Rhode Island, and while I might personally like to see the state of Rhode Island covered in slimy greasy green algae, it’s probably not the best weather for cost-effective production. But we’ve got a lot of land out here in the west, most of it sunny and a whole lot of it either not arable, or not really economical for farming. And 1.9 million acres is only 36 times the size of the cattle ranch on which I grew up — or about 1.2 times the size of the King Ranch.
Trent, you are correct. I misread the UIG table. Thanks for pointing this mistake out along with the one John M noted. I guess this calls for an update to the post, or at least a detailed correction in a comment.
What is the biofuel yield from algae growing in ponds that are frozen 6 to 8 months per year?
People who want energy independence should grow a few pollarded or coppiced trees. This was a widespread practice in the UK until well into the 20th century. The local woods were full of them when I was a kid in the 1960s. These practices produce a regular supply of wood that can easily be cut using a handsaw into convenient lengths for fire wood, unlike regular trees.
http://en.wikipedia.org/wiki/Pollarding
Shell has a process that they claim will produce light sweet from oil shale for about $50 per barrel. Why haven’t they started producing with oil prices over $100??
Well, why hasn’t anyone started drilling on the outer continental shelf or in ANWR!!! In spite of the rhetoric currently emanating from the Hot Air Capital of the US, Congress has them BLOCKED!!!!!
http://money.cnn.com/2008/06/06/news/economy/birger_shale.fortune/?postversion=2008060617
Basically the Democratic party wants to shut down use of non-renewable, Carbon based energy.
For all the algae comments about problems with ponds:
http://www.cnn.com/2008/TECH/science/04/01/algae.oil/
Vertical stands are most efficient and allow the best control of the growing environment and extraction of the algae for processing. It is also the most efficient use of the solar and land resources compared to horizontal.
Caleb,
“At some point (2005?) Realclimate actually had a post where they claimed to be able to use isotopes of Carbon 12 and Carbon 13 to tell the difference between “new” Carbon and “old” Carbon. (Let us hope we are not required to only use the “new” Carbon.)”
Carbon 12 and Carbon 13 are both stable isotopes (unlike Carbon 14), as a result they cannot be used as time markers (radiocarbon dating is based on the change of the ratio of C14 over time due to its rate of decay being precisely know; C13 is not radioactive, so its concentration in a sample does not change with time in any predictable way). The C12/C13 ratio could be used as a plant-origin marker since plants find it easier to absorb C12 over C13 in photosynthesis (someone has used that as an ocean temperature marker by detecting the C12/C13 ratio in ocean sediments, I believe), but since Oil (“old” Carbon?) and wood (“new” Carbon?) are both of plant origin (according to most theories) the C12/C13 ratio cannot be used to distinguish between CO2 from burning Oil and CO2 from a forest fire. The C12/C13 ratio could be used to distiguish volcanic from plant origin, though.
Still, are the radiative properties of (C12)O2 and (C13)O2 different enough for it to matter?
As for your primitivist impulses towards mon-and-pop energy production, you are welcomed to them; just make sure you do not dare make me pay for them (subsidies) or interfere (regulation) with my economies-of-scale more efficient energy generation; otherwise we will have a problem…
[…] Algal Fuels and Massive Scales « Watts Up With That? #biofuels #energy […]
Caleb, I discovered that reducing my electric water-heater usage was the single-most effective step in reducing the electric bill. This is done w/a simple water-heater timer. I set it to go “on” just a half-hour a day, and it prb’ly shaved 150 kwhrs a month off my usage.
Yes, I’m alone & a family prb’ly couldn’t cut usage that much. But I’ve found I can do without hot water almost completely, other than showers.
PS. I tried turning it off completely (just turning on an hour or two before showering every couple days), but iron bacteria in the well-water grew like gangbusters in the heater, so I have to warm it once a day to keep the well-water “sterilized”.
Ben Flurie
KuhnKat: Shell has a process that they claim will produce light sweet from oil shale for about $50 per barrel. Why haven’t they started producing with oil prices over $100??
The fundamental reason is that their process is still experimental. There’s no guarantee it will work on a commercial scale. And they’re reluctant to give it a shot if there is doubt they’ll have access to large amounts of shale in the event that it works. But if it works it brings up other serious concerns — namely, it could be destructive to the environment and stress water reserves in areas that don’t have a lot of water reserves. And that’s the fundamental reason for the impasse.
To my mind there is reason to be concerned. As this article explains, Shell’s process involves sinking a series of pipes into the ground and installing heaters to heat the shale to about 700 degrees for a period of about 3 years. Then they can pump the oil from an extraction well in the center. Apparently that process requires shooting hot water into the field to stimulate flow. To prevent contamination of the surrounding area they further intend to sink another series of pipes around the perimeter and creating freeze wall. Obviously, the process is rather energy intensive. And to obtain that energy Shell proposes to build a series of very large coal-fired power plants.
Now that you know what the process entails, can you understand why some people might be a little concerned? Personally, I’m all for going after our domestic resources, but not in ways that could create havoc.
While the state of Rhode Island or Conneticutt might be required in area, compare this to the current scheme for bio-fuels using food stocks. I suspect that the area required for new corn, sugar beets, or cane equal or exceed the same. Since someone decided to use a food stock as a fuel source, new growing area will have to used to meet demand. The algae can probably better use the resources such as waters with less infrastructure changes. Since it seems to be ‘stackable’ to an extent, the ‘crop’ density is probably higher too. Sounds like a better plan than corn to ethanol, by a good measure.
Trent- Good points. I believe 8% is the maximum theoretically achievable efficiency of photosynthesis in a laboratory cell, and 1-2% is more typical for plants that love sunlight (Hoffert et al, Scientific American Compass article, 2002 has more numbers on all sources of energy). If Algae needs to be shielded from direct sunlight, then the vertical growth arrangements are the only way you could capture most of the available solar insolation. For comparison, commercial solar PV farms are about 12% efficient at making electricity, and solar thermal can be as high as 15-20%. Of course, multi-stack quaternary semiconductor solar cells can achieve as high as 40% efficiency. But they are pricey!
My guess is that commercial-scale Algae farms will have efficiencies far below 1% when a complete energy budget is properly carried out on a commercial scale design. At 5 kWhr/m^2/day average insolation in sunny Florida (from NREL website), which from personal experience is an excellent location for growing all types of Algae, a 1% efficient algae farm would produce 50 Whr/m^2/day of energy in the form of fuel. That is 0.18 MJ/m^2/day. At 34 MJ/liter for biofuel (from an earlier post), that is 5.3 ml (about 100 drops!) of fuel per m^2 per day. An acre is 4047 m^2. So we get 21.5 Liters of fuel per acre per day, or 7830 Liters per acre per year, or 2066 Gallons per acre per year. Even at an impossibly high 8% efficiency, its 16,500 Gallons per acre per year, nowhere near 100,000 Gallons per acre per year claimed in the CNN report.
For a backyard system covering 1,000 square feet, you could produce (at 1% efficiency) about 1 Gallon per week.
Still, at $4/gallon, thats an incoming revenue stream of $8K (or more) per acre per year. The next question is how that compares with total production costs.
Saw a report on the History Channel that covered some of this.
Found this from a MIT guy at http://money.cnn.com/galleries/2008/fsb/0806/gallery.plot_save_planet.fsb/4.html
For his part, Berzin calculates that just one 1,000 megawatt power plant using his system could produce more than 40 million gallons of biodiesel and 50 million gallons of ethanol a year. That would require a 2,000-acre “farm” of algae-filled tubes near the power plant. There are nearly 1,000 power plants nationwide with enough space nearby for a few hundred to a few thousand acres to grow algae and make a good profit, he says.
Still would require 10+ coal fired plants. Doesn’t say what the cost/power requirements the coal plants would loose to get the flue gas ready for the plants
[…] Novel Energy Production Method + Abundant Source of Fuel for NEPM = Energy Crisis… Solved! […]
do it. eat the carbon now. in the mean time: Drill here. Drill now. Pay less.
[…] Algae Power […]
This will certainly help the world to go GREEN !!!
Let’s not use the vast amounts of land for algae. Instead, let’s use the technological breakthrough from Origin Oil.
With their new cascading process, the use of massive amounts of land is no longer needed. Plus, it can be produced right next to the refineries, so we won’t need nor incur all the costs of oil transportation to refineries.
We don’t need to drill our oceans nor Alaska.
This can now be produced on a massive basis and we won’t be reliant on foreign countries for our oil once it gets ramped up around the country.
ETHANOL-PRODUCTION WITH BLUE-GREEN-ALGAE
A SOLUTION AFTER PEAK-OIL AND OIL-CRASH
University of Hawai’i Professor Pengchen “Patrick” Fu developed an innovative technology, to produce high amounts of ethanol with modified cyanobacterias, as a new feedstock for ethanol, without entering in conflict with the food and feed-production .
Fu has developed strains of cyanobacteria — one of the components of pond scum — that feed on atmospheric carbon dioxide, and produce ethanol as a waste product.
He has done it both in his laboratory under fluorescent light and with sunlight on the roof of his building. Sunlight works better, he said.
It has a lot of appeal and potential. Turning waste into something useful is a good thing. And the blue-green-algae needs only sun and wast- recycled from the sugar-cane-industry, to grow and to produce directly more and more ethanol. With this solution, the sugarcane-based ethanol-industry in Brazil and other tropical regions will get a second way, to produce more biocombustible for the worldmarket.
The technique may need adjusting to increase how much ethanol it yields, but it may be a new technology-challenge in the near future.
The process was patented by Fu and UH in January, but there’s still plenty of work to do to bring it to a commercial level. The team of Fu foundet just the start-up LA WAHIE BIOTECH INC. with headquarter in Hawaii and branch-office in Brazil.
PLAN FOR AN EXPERIMENTAL ETHANOL PLANT
Fu figures his team is two to three years from being able to build a full-scale
ethanol plant, and they are looking for investors or industry-partners (jointventure).
He is fine-tuning his research to find different strains of blue-green algae that will produce even more ethanol, and that are more tolerant of high levels of ethanol. The system permits, to “harvest” continuously ethanol – using a membrane-system- and to pump than the blue-green-algae-solution in the Photo-Bio-Reactor again.
Fu started out in chemical engineering, and then began the study of biology. He has studied in China, Australia, Japan and the United States, and came to UH in 2002 after a stint as scientist for a private company in California.
He is working also with NASA on the potential of cyanobacteria in future lunar and Mars colonization, and is also proceeding to take his ethanol technology into the marketplace. A business plan using his system, under the name La Wahie Biotech, won third place — and a $5,000 award — in the Business Plan Competition at UH’s Shidler College of Business.
Daniel Dean and Donavan Kealoha, both UH law and business students, are Fu’s partners. So they are in the process of turning the business plan into an operating business.
The production of ethanol for fuel is one of the nation’s and the world’s major initiatives, partly because its production takes as much carbon out of the atmosphere as it dumps into the atmosphere. That’s different from fossil fuels such as oil and coal, which take stored carbon out of the ground and release it into the atmosphere, for a net increase in greenhouse gas.
Most current and planned ethanol production methods depend on farming, and in the case of corn and sugar, take food crops and divert them into energy.
Fu said crop-based ethanol production is slow and resource-costly. He decided to work with cyanobacteria, some of which convert sunlight and carbon dioxide into their own food and release oxygen as a waste product.
Other scientists also are researching using cyanobacteria to make ethanol, using different strains, but Fu’s technique is unique, he said. He inserted genetic material into one type of freshwater cyanobacterium, causing it to produce ethanol as its waste product. It works, and is an amazingly efficient system.
The technology is fairly simple. It involves a photobioreactor, which is a
fancy term for a clear glass or plastic container full of something alive, in which light promotes a biological reaction. Carbon dioxide gas is bubbled through the green mixture of water and cyanobacteria. The liquid is then passed through a specialized membrane that removes the
ethanol, allowing the water, nutrients and cyanobacteria to return to the
photobioreactor.
Solar energy drives the conversion of the carbon dioxide into ethanol. The partner of Prof. Fu in Brazil in the branch-office of La Wahie Biotech Inc. in Aracaju – Prof. Hans-Jürgen Franke – is developing a low-cost photo-bio-reactor-system. Prof. Franke want´s soon creat a pilot-project with Prof. Fu in Brazil.
The benefit over other techniques of producing ethanol is that this is simple and quick—taking days rather than the months required to grow crops that can be converted to ethanol.
La Wahie Biotech Inc. believes it can be done for significantly less than the cost of gasoline and also less than the cost of ethanol produced through conventional methods.
Also, this system is not a net producer of carbon dioxide: Carbon dioxide released into the environment when ethanol is burned has been withdrawn from the environment during ethanol production. To get the carbon dioxide it needs, the system could even pull the gas out of the emissions of power plants or other carbon dioxide producers. That would prevent carbon dioxide release into the atmosphere, where it has been implicated as a
major cause of global warming.
Honolulo – Hawaii/USA and Aracaju – Sergipe/Brasil – 15/09/2008
Prof. Pengcheng Fu – E-Mail: pengchen2008@gmail.com
Prof. Hans-Jürgen Franke – E-Mail: lawahiebiotech.brasil@gmail.com
Tel.: 00-55-79-3243-2209