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America's First Cellulosic Ethanol Plant
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."
DOE has ponied up $385 million to six different cellulosic ethanol plants, one of which is Range Fuels.
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.
Your understanding is a little twisted. It isn't "producing C02", it's shortening the carbon cycle to the point where we are using plants that have grown as recently as a few months ago for energy. The carbon in the plants was removed from the atmosphere by said plants. There may be no net reduction in C02 in the atmosphere over time by using cellosic alchohol, but burning fossil fuels presents a dramatically different situation. The carbon in fossil fuels has been buried for millions of years. This process took a very long time. Burning the fuels releases the carbon sequestered over a period of millions of years in a matter of decades.
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.
Ben Hocking
Need a professional organizer?
That's for one unit of energy WE use to produce it; all that solar power that goes into it is what we're getting out.
It's sad when choosing an installation directory on your own qualifies you as an "advanced user."
X amount of raw cellulosic product in, plus 1 unit of energy to power the process.
The output is enough ethanol to generate 16 units of energy.
In practice, these plants often loop part of the output back to power itself, so the process is simplified to:
X of raw cellulosic product in, 15 units of energy out.
Which is pretty cool.
This is the ratio of fossil energy put in to energy out. Most of the fossil energy input for corn comes from nitrogen fertilizer which is produced using natural gas (though it does not need to be http://mdsolar.blogspot.com/2007/04/smelling-salts .html) and fuel used for harvesting and planting. Some distilleries also use natural gas. Forest waste products to be used here don't have any fertilizer inputs and much of the fuel used for harvesting would have been used anyway. Brazil is achieving some very impressive values for this ratio in its biodiesel production: http://mdsolar.blogspot.com/2007/05/juicing.html. On the energy out side, everything is really stored solar power.
s -selling-solar.html
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These guys are going for ethanol though they also get some methanol, propanol and butanol. Look at step 2b here: http://www.rangefuels.com/conversion_processs -selling-solar.html
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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 has a summary of the debate.
See here:
http://fuelandfiber.com/Hemp4NRG/Hemp4NRGRV3.htm
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
Actually, plants get carbon from the air, and they do it for "free" (solar energy by way of photosynthesis). It's nitrogen that's the issue. It takes energy (and quite a bit of it) to reduce atmospheric nitrogen to a form that plants can use for protein. Fertilizer supplies nitrogen. That's where the carbon "footprint" comes in, since industrial fertilizer production burns carbon (or some alternative energy, of course).
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.
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.
A-Bomb
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 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 and between them they were successful.
FalconShould there be a Law?
OK, first we get past the blogodreck from some site that wants traffic, and look at the Range Fuels site.
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. 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.