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America's First Cellulosic Ethanol Plant
Posted by
kdawson
on Sun Jul 15, 2007 06:10 PM
from the sounds-corny-but-isn't dept.
from the sounds-corny-but-isn't dept.
hankmt writes "The state of Georgia just granted Range Fuels a permit to create the first cellulosic ethanol plant in America. Cellulosic ethanol produces ethanol from cellulose, which all plants have, instead of from sugar, which is only abundant in food crops. Corn ethanol only produces 1.3 units of energy for every unit of energy that goes into growing the crop and converting the sugar to ethanol. Cellulosic ethanol can produce as much as 16 units of energy for every one unit of energy put into the process. The new plant will be online in 2008 and aims to produce 100 million gallons of ethanol a year."
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Science: New Wonder Weed to Fuel Cars? 484 comments
Hugh Pickens writes "Jatropha, an ugly, fast-growing and poisonous weed that has been used as a remedy for constipation, may someday power your car. The plant, resilient to pests and resistant to drought, produces seeds with up to 40 per cent oil content that when crushed can be burned in a diesel car while the residue can be processed into biomass for power plants. Although jatropha has been used for decades by farmers in Africa as a living fence because its smell and taste repel grazing animals, the New York Times reports that jatropha may replace biofuels like ethanol that require large amounts of water, fertilizer, and energy, making their environmental benefits limited. Jatropha requires no pesticides, little water other than rain and no fertilizer beyond the nutrient-rich seed cake left after oil is pressed from its nuts. Poor farmers living close to the equator are planting jatropha on millions of acres spurred on by big oil companies like British Petroleum that are investing in jatropha cultivation."
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Where do these numbers keep coming from? (Score:5, Interesting)
I'd like to know because it's so hard to compare with oil at that level. It's much easier for a consumer to simply look at the price on the pump. But that only tells us what the market is willing to bear (what the fuel is worth), not the true costs of production.
Re:Where do these numbers keep coming from? (Score:5, Interesting)
If it were just about the monetary cost of things even corn ethanol wins over oil, which would be $13/gallon or more if we started charging the oil companies for our military services.
Parent
Sugar (Score:5, Insightful)
You can make cellosic ethanol from grass clippings, those bags of leaves that everyone is getting rid of each falls, fallen tree branches, corn husks, not to mention the tonnes of produce that each and every grocery store throws away every single day because it couldn't be sold.
Parent
Brazilian and Cuban sugarcane (Score:5, Interesting)
If we stopped keeping sugar prices artificially high, and especially if we let Cuban sugar in, it would be amazingly cost-effective.)
Cuban sugarcane is one reason the trade embargo hasn't been ended long ago, and why Brazilian sugarcane isn't being imported into the US. US sugarecane farmers, centered around Lake Okeechobee, FL, hold a lot of political clout.
FalconParent
Re:Where do these numbers keep coming from? (Score:5, Informative)
Comparing prices also gets subsidies (especially corn subsidies, but also renewable energy subsidies) involved.
Those numbers certainly ought to include the energy content of the fertilizer -- it's decidedly non-trivial in comparison to the output energy, though I don't have a reference handy so I won't go quoting numbers. Most fertilizer is ammonium nitrate (or other nitrates), which is made from atmospheric N2 + H2 from fossil fuel sources (mostly natural gas, but also oil and coal to some extent). The ammonia is oxidized to nitric acid and reacted with more ammonia to form fertilizer AN, or used directly as anhydrous ammonia.
Parent
Re:Where do these numbers keep coming from? (Score:5, Interesting)
Actually, it's especially easy with gas. The 'demand curve' is so steep, usually quantity demanded remains very constant regardless of price (at least, in the short term, obviously).
This is noted by gas taxes: the burden is almost entirely bore by the consumer, so an extra 18 cent tax adds nearly 18 cents to the price of gas because the companies know we'll pay it. In addition from gas taxes end up being nearly proportional to the rate.
Compare this with something like cigarettes taxes: The companies actually reduce the price of cigarettes and end up paying (I'm guessing here, from my days as a smoker) roughly half of the tax. This is directly related to the demand curve and the nature of the market. In addition, revenues are not nearly proportional to the tax rate increase because people generally do buy many fewer cigarettes when they cost more. The companies have to balance the tax burden with their loss of revenues, and they hire really smart guys to do this.
By the way, the emboldened words in this post are there to indicate trends and averages.
Parent
Re:Where do these numbers keep coming from? (Score:5, Informative)
It comes from a selection of five papers from the late nineties which did the calculation in a number of ways. Generally, they attempt to account for the entire manufacturing process, from energy in oil used in fertilizers to fuel for farm equipment, to transport of the ethanol or corn, to the refineries that distill out all the water. I do not believe they go so far as to account for feeding the farmer, but I honestly suspect that is a very minor correction, as much as I like farmers.
However, there is a fairly well known outlier which claimed to do a better job of accounting for processing costs. Pimentel and Patzek attributed what they claim are more accurate inputs to the agriculture, transport, industrial, and distribution components of the manufacturing process, giving the also oft-quoted value of around 25% energy *loss*. Ordinarily, people would probably dismiss that one given the seemingly overwhelming amount of contrary evidence, but Pimentel and Patzek are very well-respected scientists. It's difficult for me, as an energy researcher, to know who to believe. I suspect it's nigh impossible for people who only study this passingly.
Personally, I'm inclined to believe that even if Pimentel et al are wrong, 1.3 is just way, way too low to be reasonable. Improvements to technology (as this plant represents), are the only way that ethanol can ever be practical. We'll see soon enough if it's as good as they claim.
http://www.news.cornell.edu/stories/July05/ethanol .toocostly.ssl.html [cornell.edu] has a summary of the debate.
Parent
Still harder to make than corn (Score:4, Insightful)
How would hemp do?
Re:Still harder to make than corn (Score:5, Informative)
http://fuelandfiber.com/Hemp4NRG/Hemp4NRGRV3.htm [fuelandfiber.com]
Hemp is one of the top producers of biomass per acre. It is much better than corn and can be grown on fallow fields as well. And you can't even smoke this type of hemp, it grows 10-20 feet high and is all stalk with a clump of seeds at the top. Of course, nobody ever smoked this form of hemp, even when it was one of the primary cash crops of the south prior to the 1930's.
Too bad, since hemp is evil. It makes you rape white wimin: http://www.oddfrog.com/paper.htm [oddfrog.com]
Parent
Re:Still harder to make than corn (Score:5, Interesting)
Parent
How would hemp do? (Score:5, Informative)
In 1892 Rudolph Diesel designed his engine and ran it on vegetable oil. He used hemp oil amoung them. Then in the 1930s Henry Ford built a vehicle not only using hemp [wikipedia.org] in the construction but was fueled with alcohol made from hemp, hemp he grew on his Iron Mountain Estate. Hemp was found to be a good source for fuel. Also in the 1930s MIT did a study showing an acre of hemp produced more paper than an acre of forest. Eventually some who felt threatened by hemp's industrial uses pushed to make it illegal and via the 1937 Marijuna Tax Act [wikipedia.org] and between them they were successful.
FalconParent
Re:Still harder to make than corn (Score:4, Funny)
But like, chill out, man. I mean, who needs to drive to work after smoking one of these, man? I use less fuel by staying at home. Hemp is a win.... god I am hungry
Parent
In theory, the CO2 is recycled (Score:5, Informative)
In theory, the CO2 that is released from burning the ethanol is reabsorbed by the plants used to make the ethanol, so there's no net CO2. This is why ethanol and biodiesel fuels are the darlings of many environmentalists. In practice, there are other CO2 costs involved, such as (probably) fertilizer, transportation costs, conversion costs, etc. (By "costs" here, I'm referring to CO2 output and nothing else. Of course, there are other costs involved as well.)
Still, it's probably much better than burning fossil-fuels with respect to CO2 output.
Parent
How does this meme get propagated? (Score:5, Insightful)
Biodiesel is not a carbon SOURCE. Petrodiesel is a carbon source in that it takes carbon that was NOT part of the biospheric carbon cycle before and MAKES it part of the carbon cycle.
This is not hard to understand. Try retaking 9th-grade earth science, chief.
Parent
Cellulosic? (Score:5, Funny)
DOE has funded five others (Score:5, Informative)
Skeptical (Score:5, Interesting)
Re:Skeptical (Score:5, Informative)
The energy contained in 150,000 gallons of diesel @85% = 150,000 gallons/year x 133,000 BTU/gallon x .000293 kwh/BTU = 5.8MMkwh/year acre. The energy falling on one acre of land = 5kwh/m2 - day x 365 days/year x 4046 m2/acre = 7.4MM kwh/year - acre. 5.8/7.4 = .78. That is about 78% efficiency in converting sunlight to liquid energy.
I incorrectly remembered the 85% figure, which is a different measure, but it's still in the same neighborhood.
Looking at your calculation, you seem to have forgotten to convert BTUs into joules. 1 BTU = 1,054 joules. That put your calculation out by a factor of 1000. You got 0.07%, when the actual number is closer to 70%.
I wish you were right though.
Parent
Nip / tuck (Score:5, Funny)
Getting past the blogodreck, it's a minor step. (Score:5, Informative)
OK, first we get past the blogodreck from some site that wants traffic, and look at the Range Fuels site. [rangefuels.com]
This is funded by Kosla Ventures, which is Vinod Kosla's venture capital fund. That's a good sign; he has a decent track record as a VC. (He was one of the founders of Sun, but he later invested in Excite.) Anyway, they're not looking for money; they've got that.
People have been working on cellulostic ethanol for a while. It's not that hard to do; it's hard to do cost-effectively. Here's an overview of the known approaches. [purdue.edu] Range Fuels uses a heat-driven process, which of course takes energy to run, but is standard chemical engineering. There's other R&D underway to develop a bioengineered enzyme that will digest cellulose at commercially feasible rates. Such enzymes have been created, but they're too slow and making the enzymes costs too much. Work continues.
Anyway, this doesn't look like the big cellulostic ethanol breakthrough. But it's progress.
Re:Anything like this is a good thing (Score:5, Interesting)
The carbon-hydrogen class of molecules have excellent energy storage properties, from methanol (CH4) up to octane (C8H18). Some have higher energy density, cleaner burning, etc. Humanity has around 100 years of investment into the internal combustion engine and it would be wise not to do away with that until we've found something SIGNIFICANTLY better. And by significantly, I don't mean 20-30%. I'm thinking more like 100-300% before it really looks worthwhile.
Anyhow, if we stopped introducing EXTRA carbon back into the surface carbon cycle thats been sitting locked away for the last 10M+ years that'll be enough to do one of two things: stop any potential increase in surface temperatures OR show us that there is a different cause than CO2 causing warming.
Parent
Re:I wonder what the emissions are like? (Score:5, Informative)
Parent
Re:Free energy (Score:4, Informative)
Parent
Re:Carbon neutral? (Score:5, Informative)
There's your problem, right there.
Plants mine the air for carbon. They literally suck up CO2 in their leaves and use sunlight to break it into C and O2. (Technically the 02 from CO2 is turned into glucose, and two Os from H2O are released as O2)
Plants mine soil for other minerals they need to grow, mostly nitrogen to make amino acids.
Petroleum-based fertilizers are primarily Ammonium nitrate, which contains no carbon at all. In fact, carbon would be an undesirable contaminant in fertilizer.
In addition, there are bacteria that are able to get nitrogen out of the atmosphere, and several species of plants incorporate these bacteria in a symbiotic relationship. If you use the bacteria, you don't need nearly as much fertilizer.
Parent
Re:USA's first plan, not America's First (Score:5, Funny)
Parent