CORN STOVER: The remnants (or 'stover') of corn after it's harvested can be a good source of biofuel, especially when combined with the right enzymes.
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"Visualize three tons of moldy bread." It's not the most appealing image, perhaps, but it's a description of the moist mound of growth media tended by bioscientist Cliff Bradley and his partner, chemical engineer Bob Kearns at their biofuel facility in Butte, Mont., that could help cut ethanol costs at the fuel pump.
Selected soil fungi that eat cellulose—the hard-to-digest, structural component of woody plants—thrive on the big pile of putrefaction from which Bradley and Kearns harvest certain powerful enzymes. The special enzymes allow standard biofuel plants to produce ethanol at lower cost by replacing some of the high-priced corn (starch) they process with cheaper corn stover "waste"—the leaves, stalks, husks and cobs of the maize plant itself.
Replacing 35 percent of the corn (which goes for $4.28 a bushel) now used in a typical ethanol plant with inexpensive corn stover (at $65 per ton) could save a quarter on each a gallon of ethanol the facility produces, the researchers calculate. And that's before any blender's credit or tax benefits from government for processing cellulose. Bradley and Kearns say that the basic integrated starch–cellulose process also works for biofuels produced in Brazil where ethanol is distilled from sugarcane and bagasse, or highly cellulosic cane plant residue.
Supporting development of the promising new technology is Cupertino, Calif.–based AE Biofuels, which has constructed a commercial pilot facility in Butte, where the pair demonstrates their integrated fermentation technology to potential licensing customers. The patent pending process "can be a bridge to cellulosic ethanol," says Andy Foster, executive vice president at AE Biofuels. The use of cellulosic feedstocks effectively enables farmers and producers to squeeze more ethanol from each acre of farmland, he states.
AE Biofuels is one of several companies in the U.S. that is trying to jump-start progress toward greener biofuels made from nonfood feedstocks with high cellulose content. But most of the demonstration efforts have slowed or halted "since the banking meltdown which made it very tough to arrange capital," says biofuels expert George W. Huber, a chemical engineer at the University of Massachusetts Amherst. Despite last year's economic turmoil, however, new pilot cellulosic biofuel plants were opened by KL Energy, Verenium Corp., and POET, LLC, he notes.
For the past few decades, Bradley and Kearns—self-styled "industrial fermentation guys"—have focused on developing effective ways to raise hard-to-cultivate soil fungi that secrete the crucial enzymes. Unlike their competitors, they grow fungi on the moist surfaces of solid nutrient particles. Standard large-scale fermentation processes, in contrast, take place in water-filled tanks. "They put an organism in a tank where everything's in a water solution," Kearns explains, "and then they try to get enough oxygen in there to make the aerobic fungi happy." Rather than "trying to adapt the organism to a desired environment," the two researchers created an environment that suits the organism.
One of the pair's special enzymes readily degrades cellulose and another has the unique ability to break down corn starch at ambient temperatures, a talent that enables existing corn ethanol plants to incorporate cellulosic feedstocks into their standard starch fermentation processes. "The integrated process uses the same equipment, which is important now that capital financing is so hard to get," Bradley says.
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28 Comments
Add CommentHow much of the stover was supposed to go back into the land in soil making?
Reply | Report Abuse | Link to thisAn ecological system uses "waste" of one aspect as "resources" for other aspects. This is starkly contrasting to technofix perspectives. Technology has inputs, processes and outputs, but also "waste products" as "side effects". With "special enzymes" that have been available in soil organisms (bacteria, fungi, etc.) the "waste" is a "resource" that is recycles and increases soil productivity. This is economically "free" and biologically "complex system recycling" that produces a sustainable and resilient system. For experimental results, a beginning place is the web site from the Rodale Institute. This approach is "traditional" but not "backward" and can be adapted to "modern" needs -- unless you are focused on marketing "technology" that is expensive, largely unsustainable, and tends to reduce quality of the product.
Reply | Report Abuse | Link to thisEthanol has all the problems of gasoline except dependence on middle-Eastern nations. It will be thoroughly outdated once battery technology improves (c'mon researchers!).
Reply | Report Abuse | Link to this"Ethanol has all the problems of gasoline except dependence on middle-Eastern nations" - is a huge overstatement.
Reply | Report Abuse | Link to thisEthanol is not drilled from the earth, lots of problems avoided there. Certainly it is not problem free.
"...once battery technology improves..."
Reply | Report Abuse | Link to thisThere's a big qualifier. In the meantime, what should we do with the millions of cars that run on gasoline that can easily be converted to run on ethanol?
Also, have you considered the fact that biofuels use CO2 to grow? Last I checked, petroleum products do not.
Good god. We're still not discussing switchgrass. What a waste of an article.
Reply | Report Abuse | Link to this"Good god. We're still not discussing switchgrass. What a waste of an article."
Reply | Report Abuse | Link to thisTo help avoid a waste of your post, perhaps you can enlighten us as to why a discussion of switchgrass is a waste? While you're at it, maybe you can let us know why you're bringing up switchgrass when it's not mentioned in the article.
Am I the only one who was annoyed with the corn per bushel /corn stover per ton price comparison? The authors could have helped us who are not familiar with bushel to ton conversions by doing the math for us.
Reply | Report Abuse | Link to thisIt is -however - always good to hear that there are people out there working on ways to improve efficiencies with EXISTING fuel sources.
Why not mention that growing crop residues requires artificial fertilisers originated from fossil fuels?
Reply | Report Abuse | Link to thisPerhaps research grants should go more to second-generation biofuels that don't use fossil fuels at all.
Take a look at www.EPRIDA.com and biomass pyrolysis.
(But don't pay too much attention to 'Biochar Concerns' as they haven't done enough research into the scientific basis of their complaints).
From what I can gather from the article, this has the potential to open up ethanol production to woody, high-cellulose vegetation.
Reply | Report Abuse | Link to thisDoes anyone know of a good resource to find out the potential ethanol output of these types of plants? In other words, if a ton of corn can produce X gallons of usable ethanol, how many gallons from corn stover, sugar cane bagasse, fir trees, lawn clippings, etc.?
(Why, yes, I am ignorant of the finer points of ethanol production.)
Mr. Bradley and Mr. Kearns have definitely made a lot of progress with this!
"lithiumDueteride" forgot to factor in the need for an energy source to charge the batteries, which is commonly the electricity power grid delivered to the household or home of electicity consumer, If all car are powered by battery. New sources of energy need be available to make-up the energy consumed to charge the batteries. Developing the technology using ensyme from microbes or fungi to convert waste agri-mass to energy makes a lot of sense. Building large scale industrial strength conversion plant can generate net energy gain because the microbes need very little energy cost to do the conversion work aside from providing the ideal condition for them to survive and be productive. The main investment is in building the plant to process the waste material by chipping/mulching conveying and in large storage tanks. This New energy source can effectively reduce our dependence of imported fossil fuel needs.
Reply | Report Abuse | Link to thiswhat is the taste of the ethanol which is degraded from cellulose? Maybe it is more tasteful than the normal wine.
Reply | Report Abuse | Link to thisIs ethanol from corn really an energy source in the first place, or just fossil fuels and oil in disguise? How much fertiliser did it take to grow that corn? How much natural gas was burned in the Haber-Bosch process to get the nitrogen fertiliser out of the air? How much energy did it take to water the field during the growing seasons? How much energy did it take to mine the depleting phosphates and potassium and ship them to the corn fields and then spread them all around? In short, forget the money: what is the Energy Return on Energy Invested (ERoEI?) Some have calculated that it takes 10 calories of oil and gas energy to grow 1 calorie of food energy. As we hit peak oil, do we really want to rely on a liquid fuel energy system that may actually rely on subsidies of enormous quantities of cheap oil?
Reply | Report Abuse | Link to thisUS DOE Dr Pimentel on biofuels EROEI.
http://www.grist.org/news/maindish/2006/12/05/olmstead/index1.html
http://en.wikipedia.org/wiki/Ethanol_fuel_energy_balance
How much land is displaced from growing food to growing fuels? I'm absolutely against any FOOD being turned into FUEL or we're creating a linked food and oil market, where as the price of oil rises so to the price of grain rises. Didn't we learn from the last few years?
However, I'm with Eco-Steve, where we HAVE agriwaste we should be using that in biochar cookers to give us:-
* biochar which brings the soil back to life
* syngas / synfuel to power NOT our cars, but our agricultural sector
* farmers potential carbon credits as the biochar stays stable in the soil for hundreds, maybe thousands of years and could be a 25% wedge in our battle to lower Co2 emissions! (According to a recent worldwatch study).
Indeed, what if we rigged up Bichar plants that did not use ANY of the last batch's syngas to cook the biowaste, but instead used Concentrated Solar Power to cook the biowaste and agriwaste? Then we could save ALL the syngas for rural transport, a very important niche energy market to keep running as we transit to a post oil world and until such time as trucks can be converted into trains, cars can be electric (or just plain DONE WITHOUT through clever and trendy city design, see below).
I'm with the commentator that suggested we move to Electric Vehicles. (See TED's electric car talk here, where a "Battery Swap" program could work faster than actually fueling our cars takes now! You buy the car, not the battery, the company owns that and powers it off local wind turbines).
http://www.ted.com/talks/shai_agassi_on_electric_cars.html
But most of all, I'm cranky that no one here is thinking systemically about how our whole civilisation is going to face peak oil, peak gas, peak coal (anywhere from 2025 to 2050), peak metals, etc. It's all coming! Rather than energy efficient cars, I think we need to design energy efficient CITIES and when you think about it our CITIES are already always evolving. We've just got to steer the town planners in the right direction and make our cities "more European than European".
See this talk about a "Village town" presented to the University of NSW by Claude Lewenz, who is planning a development for 10 thousand people south of Sydney Australia where most residents will live car-free. No, not an eco-village, a *mainstream* development but 'at war with the suburbs'. As Claude says of suburbia, "there is no THERE there". We can do better, and solve many social, pollution, traffic accident and quality of life issues, and it will be incrementally rewarding to those cities that get started first as oil prices nudge up again to $200.
Movie:
http://villageforum.com/ WELL worth watching!
http://nourishedmagazine.com.au/blog/articles/how-to-build-a-village-by-claude-lewenz
4 reasons I'm against ethanol from corn.
Reply | Report Abuse | Link to this1. ERoEI, 2. Food, 3. EV's, and 4. better city design.
1. Energy Return on Energy Invested
Is ethanol from corn really an energy source in the first place, or just fossil fuels and oil in disguise? How much fertiliser did it take to grow that corn? How much natural gas was burned in the Haber-Bosch process to get the nitrogen fertiliser out of the air? How much energy did it take to water the field during the growing seasons? How much energy did it take to mine the depleting phosphates and potassium and ship them to the corn fields and then spread them all around? In short, forget the money: what is the Energy Return on Energy Invested (ERoEI?) Some have calculated that it takes 10 calories of oil and gas energy to grow 1 calorie of food energy. As we hit peak oil, do we really want to rely on a liquid fuel energy system that may actually rely on subsidies of enormous quantities of cheap oil?
US DOE Dr Pimentel on biofuels EROEI.
http://www.grist.org/news/maindish/2006/12/05/olmstead/index1.html
Also see:
http://en.wikipedia.org/wiki/Ethanol_fuel_energy_balance
2. Food
How much land is displaced from growing food to growing fuels? I'm absolutely against any FOOD being turned into FUEL or we're creating a linked food and oil market, where as the price of oil rises so to the price of grain rises. Didn't we learn from the last few years?
However, I'm with Eco-Steve, where we HAVE agriwaste we should be using that in biochar cookers to give us:-
* biochar which brings the soil back to life
* syngas / synfuel to power NOT our cars, but our agricultural sector
* farmers potential carbon credits as the biochar stays stable in the soil for hundreds, maybe thousands of years and could be a 25% wedge in our battle to lower Co2 emissions! (According to a recent worldwatch study).
Indeed, what if we rigged up Biochar plants that did not use ANY of the last batch's syngas to cook the biowaste, but instead used Concentrated Solar Power to cook the biowaste and agriwaste? Then we could save ALL the syngas for rural transport, a very important niche energy market to keep running as we transit to a post oil world and until such time as trucks can be converted into trains, cars can be electric (or just plain DONE WITHOUT through clever and trendy city design, see below).
3. EV's.
I'm with the commentator that suggested we move to Electric Vehicles. (See TED's electric car talk here, where a "Battery Swap" program could work faster than actually fueling our cars takes now! You buy the car, not the battery, the company owns that and powers it off local wind power).
http://www.ted.com/talks/shai_agassi_on_electric_cars.html
4. Better Town Design.
But most of all, I'm cranky that no one here is thinking systemically about how our whole civilisation is going to face peak oil, peak gas, peak coal (anywhere from 2025 to 2050), peak metals, etc. It's all coming at us really fast. So rather than energy efficient cars, I think we need to design energy efficient CITIES and when you think about it our CITIES are already always evolving. Town planners approve vast areas of urban sprawl. I think they need re-educating and steer the town planners in the right direction and make our cities "more European than European". Someone already plans our cities, don't confuse this as a "free market V Planned economy" debate and strawman. No, sadly the Western world has planned it's way into this mess. It's time to plan our way out of it.
See this talk about a "Village town" presented to the University of NSW by Claude Lewenz, who is planning a development for 10 thousand people south of Sydney Australia where most residents will live car-free. No, not an eco-village, a *mainstream* development but 'at war with the suburbs'. As Claude says of suburbia, "there is no THERE there". We can do better, and solve many social, pollution, traffic accident and quality of life issues, and it will be incrementally rewarding to those cities that get started first as oil prices nudge up again to $200.
Movie:
http://villageforum.com/ — WELL worth watching!
http://nourishedmagazine.com.au/blog/articles/how-to-build-a-village-by-claude-lewenz
1 ton of corn = $152.80 @ 4.28 per bushel
Reply | Report Abuse | Link to this"Why not mention that growing crop residues requires artificial fertilisers originated from fossil fuels?" It doesn't REQUIRE fossil fuel derived fertilizer - for instance, usually fixed nitrogen comes from natural gas(Haber process) but it can come from legumes, hog, dairy, chicken manure, municipal sewage, or Azolla fern. Farming equipment can run on ethanol or biodiesel, or biogas for fixed equipment.
googling switchgrass+ethanol+yield+per+acre gets 75k+ hits
#1-bioenergy.ornl.gov/papers/misc/switgrs.html "Test plots of switchgrass at Auburn University have produced up to 15 tons ... year yields average 11.5 tonsenough to make 1150 gallons of ethanol per acre..."
#2-http://www.scientificamerican.com/article.cfm?id=grass-makes-better-ethanol-than-corn
"...Vogel and his team report this week in Proceedings of the National Academy of Sciences USA that switchgrass will store enough carbon in its relatively permanent root system to offset 94 percent of the greenhouse gases emitted both to cultivate it and from the derived ethanol burned by vehicles."
I wonder how far I could drive on my yard waste, or if it could at least fuel my mower.
Reply | Report Abuse | Link to thisGreener biofuels from non-food feedstock is a very promising development. If special enzymes from soil organisms can be harvested to do this more efficiently and cost effectively,then that is almost manna from heaven, provided the net carbon effects from life cycle calculations are favorable to a climate friendly technological regime. They have created ambient conditions to raise hard-to-cultivate soil fungi that secrete the crucial enzymes. Unlike their competitors, they grow fungi on the moist surfaces of solid nutrient particles,under this ambient atmosphere which makes it more cost effective and ecofriendly. There is of course the competition from biomass pyrolysis and technologies/processes for second-generation biofuels that don't use fossil fuels at all. As a bridge to cellulosic ethanol,use of cellulosic feedstock effectively enables farmers and producers to derive more ethanol from each acre of farmland. That is the great attraction for enzymes that degrade cellulose for biofuel production. Forest residue and agro waste as biomass resources in the developing world can be better utilized through cellulose degrading enzymes.This can be part of an integral policy incorporating algal sources for biofuel ,and biomass pyrolysis.
Reply | Report Abuse | Link to thisS.SURESHKUMAR,SCIENTIST AND ADVISER,NIIST,CSIR,INDIA
Apparently 10 tons of biomass = 3 tons of "fuel" (syngas/synfuel?) and 1 ton of biochar. (www.eprida.com)
Reply | Report Abuse | Link to thisEthanol may have its place in an integrated waste water management and energy system, say, growing switch-grass from sewerage. Any left-over pulp after the ethanol fermentation might go into local fertiliser? Love to see a study on that. But the bottom line is, food will dominate our concerns in the coming years as peak oil, gas, and coal hit, and as the world hit's peak phosphorus around 2030-2040.
So as peak phosphorus hits so soon we SHOULD be discussing an integrated waste water / energy / fertiliser scheme that recycles our waste, purifies our water, and gives us some energy in the process. This means our departments of sewerage and waste management should probably be speaking to our departments of agriculture, and it may even affect future city design principles!
But there is hope. The "Cradle to Cradle" design philosophy operates around the waste = food principle (either biological or industrial waste can be recycled into the next generation of products, and product design has the NEXT iteration in life cycle in mind in the original design for ease of recycling.)
So we get easy to disassemble shoes, non-toxic carpets that can be thrown on the garden as they are biodegradable, etc. But we'd better get a move on, as oil is currently the lifeblood of the construction industry and our main means of building the next generation of energy systems. EG: Sitting back and wondering what 40 thousand miles of high-tech algae farms in New Mexico is a nice dream, but do we have time to build it before the world economy implodes after the final oil crisis starts around 2012-2015?
Eclipse : Yes, using Biochar technology is better than most mineral fertilisers, in that it converts biomass into organic fertiliser. Biochar technologists are now working to convert human sewage residues into hydrocarbons rather than having them going to landfill where they gas off methane, a greenhouse gas. Again this biochar method uses no fossil fuels whatsoever, as pyrolysis is a self-sustaining reaction.
Reply | Report Abuse | Link to thisHi Eco-Steve,
Reply | Report Abuse | Link to this(sorry about the earlier double posting... I was still writing it when something happened).
Biochar only partially reduces our need for NPK artificial fertilisers. Even proponents talk of it reducing Nitrogen input by about 30%. While I can see how we could make up the other 70% of nitrogen, any ideas about the PK, especially addressing "peak phosphorus"? Just wondering if you'd seen any estimates on exactly what we could reclaim from our sewerage in a truly closed loop waste / energy / food system. 20% of the original phosphorus, all of it, any %? Interesting... I didn't think something like sewerage would "char". ;-)
Also is kitchen waste better off going through a biochar cooker into syngas from a *fertiliser* perspective? See "Kompogas" ferments the whole thing into methane (I think, from memory) and then has a fantastic organic fertiliser that might supplement the biochar?
One day I'm sure we'll crack the right mix of energy, biochar, and organic fertiliser and microbe systems, maybe even mixing in a little of the "Omnivore's Dilemma" solution of swapping crop land as grazing land for a few years of cow wee and pooh to bring it back to life. There's just got to be an answer there somewhere! Anyway, good to meet another biochar enthusiast.
@candide "Ethanol has all the problems of gasoline except dependence on middle-Eastern nations" - is a huge overstatement.
Reply | Report Abuse | Link to thisEthanol is not drilled from the earth, lots of problems avoided there. Certainly it is not problem free."
The problem with Ag based ethanol is that it does require oil to produce- everything from the fertilizers to the heavy machinery to plant, maintain and harvest. So essentially you are planting oil in the ground in order to get oil. That is why low input "crops" like switchgrass would be better for BioFuels. This is an improvement it seems however, because the corn is being grown any way, and harvesting the waste as well for fuel is intriguing.
Diesel is the answer. Cultured algae is the means.
Reply | Report Abuse | Link to thisThe Valcent piece about "ONLY 10% of New Mexico would supply America with all its energy needs" just cracks me up. Sure algae is part of the "solution", but if peak oil hits around 2012-2015, we could be losing 5% to 8% of world oil production and prices will skyrocket. Just calculate how many million barrels a day that is, and then when you realise that the MEANS of building 40 thousand square miles of high tech glasshouse is a prosperous, oil rich country.... you start to get a glimpse of the problem. When you also realise that after we've adjusted to a 5% decline one year and are busy building greenhouses as fast as possible there's STILL another 5-8% drop the FOLLOWING year to adjust to... and pretty much every year following, THEN you are approaching the scale of the problem. And when you go looking for all the nutrients to make that algae grow and realise for it to be sustainble you have to rig these glasshouses up to our sewerage treatment plants, and that many industries dump certain nasty metals into the sewerage, and that this has to stop and we have to develop and integrated waste / energy / food system, THEN you've pretty much got the problem.
Reply | Report Abuse | Link to thisIn summary:
Reinventing practically everything we do in an increasingly energy scarce world.
So the only answer is to build energy efficient CITIES that are "more European than European", upgrade rail systems on renewable electricity, and whack up those high ERoEI wind turbines. They seem to the be the quickest way to get some real energy "bang" for your buck. Only it IS electricity, not liquid fuels, but we can gradually move to EV's AND rezone vital village cores in our urban sprawl to try and do without cars in the first place. And it's a better way to live. See...
http://villageforum.com/
And here it is! Waste, algae, food, methane energy, biofuel oil, all in an integrated system. Won a 15 year old $20, 000! Hot off the press.
Reply | Report Abuse | Link to thisSounds like SCIAM needs to run an entire podcast on this?
http://www.inhabitat.com/2009/06/24/versatile-system-by-javier-fernandez-han/
Will we then loose the biomass that normally is returned to the soil? So the land used in this way will become poorer, probably by more than the 25 cents saved.
Reply | Report Abuse | Link to thisThe problems with batteries are: The batteries themselves.
Reply | Report Abuse | Link to this1; They don't generate power. They only store energy generated else where.
2. They are expensive, heavy, big, take a long time to charge-up.
3. They contain corrosive and polluting chemicals and therefore cause much pollution during manufacture and, especially, at disposal.
The researchers should put more efforts in direct methanol (or ethanol) fuel-cells. Like petrol, these fuels only need empty space to hold-- at the cost of a few sheets of formed metal.
Reply | Report Abuse | Link to thisDear Sir/ Madam,
Good Morning.
Basis of Environment friendly crop-based Balanced Fertilizer Rcommendation for Crops:
Integrated organic and inorganic fertilization is needed to
increase the yield of crops. Fertilizer policy
is initiated based on the longterm experimental findings,
practical experience and observations.Fertilizer
recommendation for any crop is made depending on soil,
plant analytical results, yield of crops.so, reach
desired goal checked-climate,plant population,pest and
disease control measures,the critical values of
specific crop soil in specific areas.More at
www.northernfertilizer.org
Thanking You
Kbd. Durlave Roy
R and D MANAGER and International Executive
NORTHERN AGRO SERVICES LTD,BANGLADESH.
Krishibid. consultation@yahoo.com
Reply | Report Abuse | Link to thisDear Sir/ Madam,
Good Morning.
Basis of Environment friendly crop-based Balanced Fertilizer Rcommendation for Crops:
Integrated organic and inorganic fertilization is needed to
increase the yield of crops. Fertilizer policy
is initiated based on the longterm experimental findings,
practical experience and observations.Fertilizer
recommendation for any crop is made depending on soil,
plant analytical results, yield of crops.so, reach
desired goal checked-climate,plant population,pest and
disease control measures,the critical values of
specific crop soil in specific areas.More at
www.northernfertilizer.org
Thanking You
Kbd. Durlave Roy
R and D MANAGER and International Executive
NORTHERN AGRO SERVICES LTD,BANGLADESH.
Krishibid. consultation@yahoo.com