Sweet Sorghum for Ethanol

David Leppik

Tue May 13 08:30:06 -0700 2008

First line of the article:

"We consider sweet sorghum an ideal 'smart crop' because it produces food as well as fuel," William Dar, Director General of the non-profit International Crops Research Institute for the Semi-Arid Tropics (ICRISAT) said in a statement.

That's exactly what people are complaining about with corn! So which is it, are dual-use crops good or evil?

Sweet Sorghum for Ethanol

chinakow

Tue May 13 10:55:10 -0700 2008

Corn produces food OR fuel, Sorghum has an edible part AND an a part that can be converted to fuel, that is the difference.

Sweet Sorghum for Ethanol

Aero	Tue May 13 11:11:04 -0700 2008

Corn does both as well - after the sugars are removed and fermented, the leftover distillers grains is used for livestock feed. And since about half of all corn grown in the US is fed to livestock anyway, the whole "food vs. fuel" debate is rather overblown.

Sweet Sorghum for Ethanol

TykeClone

Tue May 13 11:14:42 -0700 2008

Shh.  Don't confuse them with facts.

Sweet Sorghum for Ethanol

chinakow

Tue May 13 13:20:42 -0700 2008

Okay, as if my first posting wasn't all hearsay, here is some more. If I remember correctly the waste products of corn, like the stalks and whatnot are not really big on giving up the sugars like the kernels are so it is more productive to use the kernels thus, the food problem. Also the BBC global news podcast ran a bit about sorghum yesterday and of course I deleted it after listening. In it they stated essentially what I did above. that it is a hearty plant, and produces a liquid in the stems that is good for turning to ethanol. Of course I can't currently back that up other than saying that I had a chemistry instructor hit us with the former.

The latter I did just find here mp3 where at 24:21 Mark Winslow of the International Crops Research Institute says, ". . . and now we are developing a new use for it which is, a third use, which is to produce, biofuel from the juice in the stems of the plant." He goes on to say that it is not really used as a major food stuff in urban areas so it isn't a competitor as a food crop. He also says that it might not be the savior people are looking for. Also at 26:12 he answers the question why it is better than other biofuel crops by saying, ". . . [I]t produces both, biofuel in the stem and it produces grain at the top of the plant." Stating that you don't have to make the choice between fuel or food. Also he mentions again that it is not a major food crop. So he may be mis-informed but what he says is in line with what I had heard before. Do you have new information about the whole plant being used in corn to ethanol production? Also the point he makes about sorghum not being a major food crop seems relevant.

Sweet Sorghum for Ethanol

Aero	Tue May 13 13:31:40 -0700 2008

"Do you have new information about the whole plant being used in corn to ethanol production?"

 

There are certainly a lot of people working on making cellulosic ethanol from corn stover, but I'm not really convinced it won't cause other problems. 

It isn't like farmers just pick the corn kernels and throw the rest of the plant in the garbage.  They either till it back into the ground to enrich the soil or they turn it into cattle food. So there already is little to no waste.

Sweet Sorghum for Ethanol

chinakow

Tue May 13 15:04:50 -0700 2008

I quoted Mr. Winslow saying, ". . .a third use. . ." That is what I am talking about. Feed for live stock, feed for humans, and biofuel. Getting back to your original question where I asserted that sorghum can make food and fuel and corn can't, I was referring to food for human consumption and I meant concurrently. Sorghum can be harvested for its grain and then the remainder can be used to make fuel and still have leftovers for livestock feed. So yes, corn does both make ethanol and feed for cattle. Corn does not, however, produce food for human consumption at the same time.

Sweet Sorghum for Ethanol

Aero	Tue May 13 19:23:33 -0700 2008

Feeding cattle does indirectly feed humans, by transforming a lower quality food item (corn) into a higher quality items (meat and milk).  Just like refining crude oil transforms a low value substance into a high value fuel (gasoline). 

When was the last time you ate sorghum or a sorghum product?  AFAIK, the only human edible part of sorghum that is typically used is the sugar - which is consumed to make ethanol.  Besides, it isn't like humans are currently eating field corn, except when processed into things like corn syrup.

Sweet Sorghum for Ethanol

chinakow

Tue May 13 23:06:00 -0700 2008

David Leppik asked, "So which is it, are dual-use crops good or evil?" I replied that this particular crop is more dual use than corn because of the ability to produce food(directly for human consumption) and fuel without having to choose which one. Now you are changing the subject. The previously sited audio interview from the BBC actually contradicts your above statement saying that the grain of sorghum is edible and that the juice of the stems can be used to produce fuel. Further, so what about people not eating field corn? I never said we do and it isn't relevant to the question of whether or not sorghum is a better dual or, in this case, triple use crop. People have been decrying the use of corn for making ethanol for some time now because of the increase in the price of sweet corn. Remember the riots in Mexico because the price of tortillas doubled? I would hazard a guess that sweet corn is better for making ethanol because it is sweet and therefore, contains more simple sugars than field corn.

Also refining oil doesn't transform it into gasoline, it extracts the gasoline from the other products that are also present in crude oil, things like kerosene and diesel.

Sweet Sorghum for Ethanol

Aero	Tue May 13 23:52:46 -0700 2008

Someone can correct me if I'm wrong, but once you take the sugar out of sorghum, I really don't think you have a human edible product. I certainly have never heard of anyone eating sorghum grain. Maybe you can feed it to cattle, but that is my point about corn (correcting your original statment "Corn produces food OR fuel").

Regarding the Mexican torilla riots, I hate to interject facts again, but that had almost nothing to do with ethanol and everything to do with trade protectionism and a bad harvest in Mexico.

Field corn vs. sweet corn: field corn has an 80 year history of being selected and crossed to develop traits that make it well-suited for large scale livestock and ethanol use - namely yield, moisture (lower the better), and a few others like stalk strength, ear height, and other traits that keep it from blowing over and/or breaking. Sweet corn has been selected for very different traits, and even if it were better for making ethanol (I doubt it...the moisture content alone would kill any chance of making cost-effective ethanol), you couldn't grow enough of it.

Sweet Sorghum for Ethanol

The Baron

Wed May 14 07:05:31 -0700 2008

Just one more thing to throw into the discussion. As has been pointed out above, the corn being diverted from human food to ethanol production is a pretty big red herring. Most of the corn used for ethanol production goes right back as feed stock for cattle, so there should be little impact on the amount available for human consumption. The only, slightly, credible argument I've heard, and can't confirm, is that farmers are replacing other food crops with corn to sell to the ethanol market, thus causing shortages in wheat, soy, etc.

Now corn is actually a fairly finicky product as far as requiring good growing conditions and good land. One of the breakthroughs with using sugar cane for ethanol, and now it seems sorghum, is that it grows in pretty nasty conditions unsuited for other crops. Thus an increase in sorghum production should bring into useful production land that is unused now, and shouldn't reduce the acreage being used for human food stock.