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Is Domestically Produced Ethanol Worth the Cost?

scientificamerican.com

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Re: Is Domestically Produced Ethanol Worth the Cost?

#12
post #8
post #5

Earlier quoted context omitted.

A very promising technology I've had the chance to work with is called SwiftFuel. It's based of switchgrass, which is far more sustainable. The FAA, due to pressure from the EPA, is looking to switch the entire aviation industry to SwiftFuel from low-lead fuels. More info: http://en.wikipedia.org/wiki/Avgas#Swift_fuel SwiftFuel has the advantage of being able to run, in theory, in most/all aircraft engines without mo…

One problem, land that is ready to grow such crops is finite in supply not infinite..ie same land that corn was used..which will also impact food supplies..

Biofuel researcher here: The nice thing about switchgrass is that it's a much hardier plant, meaning that you can get it to grow on marginal lands, which means land that wouldn't otherwise be used for crops.

Getting people to grow anything for biofuels is a bit of a double-edged sword, as you want the feedstock to be as cheap as possible, but you also want it to be profitable for the farmers to actually produce so that you can get enough of the biomass. If you improve the yield of viable biomass from the plants that'll go part of the way to solving this.

Re: Is Domestically Produced Ethanol Worth the Cost?

#13

Ethanol itself is far superior to petroleum distillates for internal combustion engines, especially small displacement turbocharged ones. This point needs to be made /extremely/ clear to everyone before pursuing the political end of the discussion.

I don't see why that needs to be extremely clear for this discussion. But regardless:

Where the octane number is raised by blending in ethanol, energy content per volume is reduced. Gasoline has an energy density of almost 10,000 Wh/l and pure Ethanol only 6,000.

Ethanol is inferior compared to basically any combination of gasoline + non-ethanol octane booster.

Re: Is Domestically Produced Ethanol Worth the Cost?

#15
post #4

A million times yes, there needs to be more awareness of how ridiculous corn ethanol is. Corn ethanol is more an indirect way of converting coal to something your car can run on. There are many other more efficient plant sources that do not require large doses of fertilizer and herbicides, usually drawn from coal energy.

I'm not going to defend corn ethanol, but I do think this debate is misguided. The problem is not the corn ethanol, the problem is the corn.

Corn is an indirect way of converting oil into sugar. It is just as inefficient at making food as it is at making fuel (though that's less obvious because the end product doesn't have the same units.) There's a great article in an old issue of Harper's called "The oil we eat" (http://www.harpers.org/archive/2004/02/0079915).

I find it amazing that people are complaining that diverting corn to make ethanol raises food prices, when you can make the same argument that diverting corn to feed cattle raises food prices. Making beef via corn is an extremely inefficent method that's only viable because of cheap oil.

If the real concern is feeding people, you eat vegetarian. From a food supply point of view it's pure waste to feed cattle food that humans can eat directly. (Letting cattle eat grass on land not suited for agriculture is different.) The only reason it's sustainable to raise cattle the way it's done in the U.S. is because of an abundance of cheap corn due to cheap oil.

Re: Is Domestically Produced Ethanol Worth the Cost?

#16
post #8
post #5

Earlier quoted context omitted.

A very promising technology I've had the chance to work with is called SwiftFuel. It's based of switchgrass, which is far more sustainable. The FAA, due to pressure from the EPA, is looking to switch the entire aviation industry to SwiftFuel from low-lead fuels. More info: http://en.wikipedia.org/wiki/Avgas#Swift_fuel SwiftFuel has the advantage of being able to run, in theory, in most/all aircraft engines without mo…

One problem, land that is ready to grow such crops is finite in supply not infinite..ie same land that corn was used..which will also impact food supplies..

I think the problem is less the amount of land than the energy intensity of the crop.

Re: Is Domestically Produced Ethanol Worth the Cost?

#17

Ethanol itself is far superior to petroleum distillates for internal combustion engines, especially small displacement turbocharged ones. This point needs to be made /extremely/ clear to everyone before pursuing the political end of the discussion.

I don't see why that needs to be extremely clear for this discussion. But regardless: Where the octane number is raised by blending in ethanol, energy content per volume is reduced. Gasoline has an energy density of almost 10,000 Wh/l and pure Ethanol only 6,000. Ethanol is inferior compared to basically any combination of gasoline + non-ethanol octane booster.

Energy/volume is irrelevant (at these levels). What really matters is the usable energy coming out the engine compared to the engine coming in. Because of its higher octane, ethanol could in principle be run in ICUs with much higher compression ratios than engines designed for gasoline use have, giving higher efficiency (like diesel engines have higher efficiencies). The problem is that no engines actually are tuned for maximum ethanol efficiency, since that makes them unusable with gasoline. (Turbocharging somewhat offsets this, which is why I assume the grandparent specified this, but only partially.)

Re: Is Domestically Produced Ethanol Worth the Cost?

#18
post #15
post #4

A million times yes, there needs to be more awareness of how ridiculous corn ethanol is. Corn ethanol is more an indirect way of converting coal to something your car can run on. There are many other more efficient plant sources that do not require large doses of fertilizer and herbicides, usually drawn from coal energy.

I'm not going to defend corn ethanol, but I do think this debate is misguided. The problem is not the corn ethanol , the problem is the corn . Corn is an indirect way of converting oil into sugar. It is just as inefficient at making food as it is at making fuel (though that's less obvious because the end product doesn't have the same units.) There's a great article in an old issue of Harper's called "The oil we eat"…

you can make the same argument that diverting corn to feed cattle raises food prices

As far as I can figure out, diverting corn to feed cattle raises corn prices and lowers beef prices.

Since beef eats up a much larger fraction of my grocery budget than corn (and is, additionally, far more delicious) I'm cool with this.

Re: Is Domestically Produced Ethanol Worth the Cost?

#19

Ethanol itself is far superior to petroleum distillates for internal combustion engines, especially small displacement turbocharged ones. This point needs to be made /extremely/ clear to everyone before pursuing the political end of the discussion.

I don't see why that needs to be extremely clear for this discussion. But regardless: Where the octane number is raised by blending in ethanol, energy content per volume is reduced. Gasoline has an energy density of almost 10,000 Wh/l and pure Ethanol only 6,000. Ethanol is inferior compared to basically any combination of gasoline + non-ethanol octane booster.

Volumetric energy density isn't the only consideration for fuels though. Ethanol burns cooler, faster, and with more stability. When you raise the octane rating to reduce detonation you also reduce wear on the internals, allowing the manufacturer to use cheaper components. The same is true for the lower exhaust gas temperatures with exhaust values and turbo inlets. Current mileage standards have also caused manufacturers to jack up cruise-area ignition timing to extract a more complete burn before TDC from gasoline, which risks increased knock, and isn't as much an issue with ethanol. I also can't fail to mention the disgusting layer of grease and soot that covers the inside of engine, gas tank, and exhaust components (and the rear end of your car) from gasoline. Again, not much of an issue with ethanol.

These strengths are almost never written about or discussed. I agree with many of the points of the article in terms of the production efficiency issues, and corn being a weak production candidate, but I can't stand if/when this becomes an ethanol-substance bashing bonanza.

I also can't stand (in the overall discourse on the matter) when the article's points are used against the adoption of ethanol over petroleum. These aren't reasons against ethanol, they're reasons to work towards optimizing the means of production.

Re: Is Domestically Produced Ethanol Worth the Cost?

#20
Corn welfare must END (and I am very liberal/progressive if that matters).

But considering it's Iowa we are talking about, most politicians if they want to be president won't touch it with a 10-foot pole.

Ethanol is destroying small engines (generators, lawn mowers, etc) and most definitely reduces mpg by 10%

   a gallon of ethanol costs approximately 17 percent less than that of a gallon of gasoline
That is why gas distributors love it - they not only get goverment welfare for using ethanol, it allows them to dilute the less profitable gasoline (to 'cut' it).

(and yes, I use "subsidies" and "welfare" interchangeably because it's corporate welfare)

   Researchers at U.S. Department of Energy’s Argonne National Laboratory 
Let's get INDEPENDENT scientists not funded by the oil industry or government to write an article and I'll trust it.
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