Prospecting for Biofuels
by Tim McGee, Helena, MT, USA on 06. 5.07
Growing corn is not the answer to our gasoline addiction, but is switchgrass, Miscanthus, or Poplar trees? And if they are, when do we harvest them to get the optimal solutions? Good questions-glad you asked. Because researchers at the U.S. Department of Energy’s Ames Laboratory are looking at ways to determine what type of plant material, and specific times of harvest offer a better long-term solution.
Analytical chemist Emily Smith has devised a test based on Raman spectroscopy that can quickly determine the chemical composition of the plant in question. Understanding the composition of the cellulose material is just as important for biofuels as is understanding when a fruit is ripe to pick for eating. Except we did not evolve any specific sense to tell us when poplar trees make for good biofuels. Which is why we need people like Emily.
“Just like vintners monitor and test the sugar content of their grapes in the field, biofuel producers could potentially use this technology to determine if their crop was at optimal development for conversion to ethanol,” said Smith. Agriculture has often been spurred by just such screening technologies, and new types of crops will require new thinking when it comes to screening.
“This method has several advantages over other analytical techniques...analysis requires very little material so you can take small samples from a growing plant over time without damaging the plant.”
Optimizing plant biomass for more efficient biofuels processing requires a solid understanding of plant cell-wall structure and function. Plant cell walls contain four different polymer types - cellulose microfibrils, hemicelluloses, pectins, and lignins. Lignins are of particular interest as they are not readily turned into ethanol, and can even cause problems in enzymatic breakdown for use of the biomass. Lignin acts like the glue in plant material, holding together other components. One way around this problem is to identify which plants have little lignin or when these plants are lignin deficient.
“We hope to find out if lignin content changes over time, with different growing conditions, or with different stock material,” Smith said, “so we can determine if there is an optimal time to harvest a particular crop.”
One way to begin to look for sustainable crops might be to take Emily's method for a test drive, and see what plants have interesting lignin properties in your neck of the woods.
Why isnt corn the answer for biofuels? There are so many billions of dollars of current infrastructure to support corn-growing, but none at all for switch grass or poplar trees. IMHO making use of new cellulose fuel technologies with an existing crop such as corn grain, or silage makes much more sense than trying to domesticate an entirely new plant species. But I'm just a farmer maybe some of you can explain to me why I might be wrong.
I believe that people living near or under the poverty line deserve to eat food before I use it to justify driving my SUV around all day because it is a "flex-fuel" vehicle . . .
I believe that people living near or under the poverty line deserve to eat food before I use it to justify driving my SUV around all day because it is a "flex-fuel" vehicle . . .
Hi Joel,
I too am a farmer from Ohio and understand your concern. I have followed this issue closely as it directly affects my family. Here is a lecture paper by a professor from University of Minnesota that he shared with us at ohio State a couple of weeks ago. If you have time to read this essay I feel it will help shed some light on the issue for you. Although I did not agree with everything he had to say, it is a worth while read. http://aede.osu.edu/resources/FordRungeLecture.pdf
Thanks,
Jesse
Joel,
Ethanol made from cellulose should apply to corn crops. Corn growers would harvest the kernels for food (as should be), and they would use the woody stalk to produce ethanol, rather than throw it away, plow it back into the ground or, worse, burn it in the fields. That way corn farmers would be selling two products - food AND fuel. However, corn may not be the most efficient plant for making ethanol. Some crops grow faster. Some grow in more inhospitable conditions and require less, or no, fertilizers, pesticides, etc. Farmers constantly try to breed the best plants, to the extent that many now use genetically modified plants in order to enhance the crops they grow in one way or another. No wheat farmer today would grow comercially the wild wheat of the Fertile Crescent from 6000 years ago. They don't look anything alike anymore. As a farmer, I'm sure you understand that farmers try to grow the crop most suited to the needs - and if corn stalks are not the most suited for ethanol production, then society - and farmers - shouldn't be wasting resources trying to expand its use for that purpose. But as I said, farmers growing corn for food should, and will, use their corn stalks to produce ethanol rather than let it go to waste.
Apparently using corn isn't as efficient as switchgrass, and we like to eat corn. Check iogen.ca for some more info - the company is located just blocks from my house!
Re: "Why isnt corn the answer for biofuels?"
Q1: CORN growing is very energy intensive. While being grown for human consumption this energy input is justified. To burn in engines, less so. Your point about using cellulose processes on corn sillage is a good one, and should be used, but it doens't mean that in terms of adding new acreage we shouldn't consider potential aliternatives
Q2: Switch grass and popular trees are seen to have higher yields per acre. Using a perrineal plants means that you don't have to till the soil and reestablish root growth which so be good for the soil erosion issue, and should reduce energy input for the cultivation and therefore increase the net energy return. I imagine that crop rotation comes into play here as well and therefore these alternatives should be investigated.
RE: "There are so many billions of dollars of current infrastructure to support corn-growing, but none at all for switch grass or poplar trees."
A: Most of that infrastructure is committed to producing corn for the needs we now (mostly food, some ethanol). An increase agriculture's role in the nation's energy supply energy will require massive investment in new infrastructure. Good sense would lead one to make the investments in crops acreage and refinement technologies that hold the highest efficiencies. Corn is not widely seen to hold this promise for the reasons I listed above.
And the beat goes on...Just read an article that India has produced a vehicle that runs on air? We have wind,solar,water & air E-sources in abundance.Why not concentrate on these instead of creating it with another E-source that is NOT energy efficient and may not be re-newable in the future.I can invision a hybred vehicle that has a combination of these elements instead of the ones that are being created now.Can't these car designers and manufacturers get there heads out of their "clouds" & our pockets,long enough to design a vehicle that doesn't include good ole' boy self interest first...IE:($$$$)?It's true....the rich get richer and the poor get poorer...and the future be damned! JA Donelson