Ethanol could leave the world hungry

Cnn.com ^ | 8-16-06 | Lester Brown

[SunkenCiv]

Brazil has been running on blends or straight ethanol for decades, and they make it out of sugar.

[John D]

any plant matter that comes off a farm it depletes the nutrient base that good soil needs for a proper crop



I think George Washington Carver solved this problem with crop rotation.

[RedMonqey]

Already been mentioned before by me and others.

Plant rotation does little if you take away the majority of the plant BEFORE it can be recycled back into the ground. And yes Carver used peanuts to restore nutrients but it isn't the plants that produce high fuel content and while the fields are "offline" not producing then reoccurring fuel shortage will happen.

Like revisiting the 70's gas lines again every couple of years.

Please read ALL my previous posts before you add your comments.

[jackieaxe]

Who cares if the world will go hungry or that it takes as much energy in fertilizer and distilling as the ethanol yields, as long as the fat cat American farmer millionaires who are subsidized left and right and protected by a 50 cent/gallon tariff are happy and making money. Next time you meet a millionaire farmer complaining about a lack of government handouts, thank a guy like Senator Dick Turbin.

[from occupied ga]

Next time you meet a millionaire farmer complaining about a lack of government handouts, thank a guy like Senator Dick Turbin.

Bob Dole was a big proponent of this too.

[jackieaxe]

Bob Dole was a big proponent of this too. [ethanol subsidies]

Yes, it's a bipartisan screwing of the American Citizen!

[TKDietz]

So you are saying nothing has changed since the 1970's except for the assumptions? That's just not true. Since the 1970's the average bushel per acre yield for corn has risen quite a bit. Also, the average number of gallons of ethanol made per bushel of corn has increased. This isn't all about thermodynamics. Distillation of alcohol is most efficient at about 172 degrees, give or take a little depending on altitude and some other factors. Distilling under a vacuum lowers the temperature required considerably, but none of that has changed since the 1970's. Yields have changed though, both in terms of per acre bushel yields and per bushel ethanol yields. Corn used in the process has been modified some, and yeasts and enzymes used in the process have been improved. They've learned a lot in the past 36 years and efficiency of the whole process from planting the corn to distilling it has improved. It probably could be improved even further. I don't really see how you can totally discount the fact that efficiency in the processes used can and have been improved, especially given that it is clear from published statistics that average per acre corn yields have improved a little just about every year in the last few decade and you have no doubt read that per bushel ethanol yields have improved as well, with modern ethanol plants now averaging about 2.8 gallons per bushel of corn.

"Yes, but if you're looking at energy production then the balance has to take into account every input. Just like business determining profit or loss - you have to take into account all expenses."

Are the calories your farm workers burn a business expense of yours? Of course not. Look, Pimentel says that gasoline is a net energy loser, that it takes 10% more energy to produce it than you end up with in the final product. The authors of the other article you linked me to went along with a positive energy balance for ethanol ranging from somewhere between 5% and 26%, saying even at the high end it wasn't very good and at the low end it was a "make work program only a politician could love" (paraphrase from memory). If it takes 10% more energy than you get in the final product to make gasoline is the oil industry worse than a make work program only a politician could love? Pimentel goes too far in assessing energy costs regardless of which fuel he is talking about. He uses old and incorrect data with respect to yields, and he makes a lot of false assumptions along the way. In the Pimentel article you linked us to for instance he claims that ethanol will in many cases take three different distillations, which is nonsense. If you use an old pot still and don't control temperature it might take three runs through the still to get rid of enough water to run the product through a molecular sieve to get the alcohol content high enough to mix it with gasoline, but no ethanol plants use such crappy old technology. They use modern column stills that produce alcohol of sufficient purity the first run every time. He and his buddy Tad Patzek all sorts of bogus assumptions in this study we were talking about and his their studies on biodiesel, seemingly believing for instance that you can't grow soybeans unless you clear cut some forrests first. The biodiesel guys also complain that the amount of lye Pimentel and Patzek claim is used in the process is about tens times that actually used. The ethanol guys claim these two don't give proper credit for the energy value of the animal feed and liquid CO2 produced in the process. Their assumptions and conclusions have been refuted again and again, and those two are about the only researchers doing studies since the mid nineties who still claim ethanol has a negative energy balance.

Maybe part of the problem is Pimentel is an entomologist and not an engineer or an economist. He's so old he's probably getting a little senile too. Patzek was a longtime employee of Shell Oil Company and founder of the UC Oil Consortium and is also a member of the Society of Petroleum Engineers, so he's probably a little biased toward alternative fuels. These guys don't publish their entire studies in peer reviewed journals. They often cite themselves as sources for data. They don't clearly state where their data or their assumptions come from. What they do spell out is easy to refute, so maybe that's why they don't believe in letting everyone in on the secrets of how they reach their wild conclusions, showing where their data came from, etc.

I'm not going to worry about this. You can believe what you want to believe. For better or worse, ethanol is here to stay.

[Fred Nerks]

Brazil has been running on blends or straight ethanol for decades, and they make it out of sugar.

----

And in the aussie North, where rainfall is abundant, the sugarcane fields go on and on for ever and ever...Australia currently is the world's sixth largest sugar producer and the third largest exporter.

Delta Electricity and the NSW Sugar Milling Co-operative Ltd have established a joint venture to use biomass from sugar milling to produce green energy.

I understand the power generated from the waste product will be in excess of the needs of the Mill and will be fed into the electricty grid.

[nomorelurker]

selfping