Atkins and Ethanol
All us Atkins guys understand why it’s easy to make fuel out of corn kernels and sugar and hard to make it out of the rest of the corn stalk, sawgrass, sawdust, and other fibers. When we drive our spouses crazy by reading the label of every can and box to check for poisonous carbs, we’re allowed to disregard all carb grams for fiber. We can’t digest the carbs out of the fiber so they do us no harm; trouble is that current ethanol plants can’t digest them either.
Moonshiners know how to make alcohol from anything with sugar or starch in it; today’s ethanol plants are just stills on a large scale. Because so much energy has to go into growing an acre of corn, transporting it, and then distilling it, the net gain in either energy independence or reduction of co2 emissions from substituting ethanol for gasoline is small; some people even dispute whether there is any gain at all although evidence seems to be that there is. There is also a cost in higher food prices as kernels that might have become high fructose corn starch become motor fuel instead.
The problem is one that an article in Science Magazine calls by the wonderful name of “biological intransigence”. Seems that plants have stubbornly evolved in a way that makes their key parts indigestible by most other species and most enzymes. The plants are willing to give up the fruit around the seed to get the seed dispersed. They have to pack some starch somewhere both for seeds and for themselves. But they don’t want their fiber to be a tempting snack so they’ve locked it in tight chemical bonds. Currently it costs us more energy to break these bonds than we get back out – sort of like pistachios with a completely closed shell.
Some animals have evolved to digest fiber. Cows are a good example although it takes them four stomachs in a row to make the process work. Every dairy or beef farmer knows that cows are marvelous machines for converting grass into methane – trouble is most of that methane ends up in the atmosphere as a greenhouse gas much more potent than co2. There are beginning to be manure powered electrical plants, however.
I’m optimistic that the chemical crackers for fiber’ll be found. This is just an engineering problem and engineering problems get solved. At that point most of the agricultural waste stream becomes a source of transport fuel – less net carbon emissions and less need to import Mideast oil. All goodness. Note that using the inedible byproducts of farming for energy production helps decrease pressure on food prices and involves little incremental expenditure of energy since the food crops are being planted, fertilized, and harvested anyway.
In the short-term until biological intransigence is overcome, I have a suggestion from an Atkins POV: make all the high fructose corn syrup into ethanol instead of adding it every conceivable product and rendering those products inedible for us carb-shunners.
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remember the atkins family cut a record with you in 1he name980s well it is a family connection. do you have the song on archive, please let me know to bad it was what you were looking for at that time it was all about vanity, appollonea, prince, and day. t
Posted by: joyce atkins | July 22, 2007 at 11:57 AM
Digesting the celluloses and lignins into ethanol is almost certainly possible (though, incidentally, many of the microbes that can do it don't actually get energy from it: they use a fraction of the energy they get from the carbohydrates wrapped inside the intransigent material). It could still be a dumb idea. You will note that there aren't, in most places, rafts of undigested intransigent material underfoot; it gets incorporated into the soil, eventually as humus. Humus makes the rest of farming a lot easier. If we think we can afford to burn off all the organic material in our soils, we really ought to just start growing everything hydroponically *now* while we have (1) relatively cheap energy to build the infrastructure
(2) some soil left to perform other handy functions, like water filtration.
Posted by: clew | May 07, 2007 at 07:42 PM
We're making great progress in creating the enzymatic soup that will quickly and efficiently breakdown natures fibrous materials and at a low cost per /X. Folks at Iowa State are unearthing research from 50 years ago and jockeying to patent these latent PhD projects that in a $30/bbl world meant nothing. We have no choice here in the US but to move beyond corn and based on my readings, within 5 years we'll have brought the cellulosic ethanol production costs well below what corn costs now. I think "the 4-stomach method" is a great catch phrase for this process.
Posted by: Doug Mitchell | April 26, 2007 at 08:36 AM
Hmmmm, remember Kurt Vonnegut's "Cat's Cradle". Cellulosic Ethanol = Ice 9. Read this thought provoking link about what can happen if the "engineering" succeeds....
http://www.forbes.com/free_forbes/2006/0410/100.html
Posted by: Anon. E. Mous | April 26, 2007 at 02:14 AM