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Burn Grass, Get Green Biofuel
Roland Piquepaille writes "Do you want to use an economical and environmentally friendly biofuel? Just grow grass. Burning grass pellets will produce an energy-efficient biofuel, according to Jerry Cherney, a professor of agriculture at Cornell University. In this news release, 'Grass as Fuel,' he says "Burning grass pellets makes sense; after all, it takes 70 days to grow a crop of grass for pellets, but it takes 70 million years to make fossil fuels." Unfortunately, there is nothing like a grass political lobby in Washington, so he might not be heard. But with current oil prices, more and more people will be tempted to use cheaper -- and cleaner -- sources of energy. This overview contains many more details and references about this environmentally friendly biofuel made from grass."
Another Roland Piquepaille story
Here is what he wrote if your interested:
samedi 2 avril 2005
Burn Grass, Get Green Biofuel
Do you want to use an economical and environmentally friendly biofuel? Just grow grass. Burning grass pellets will produce an energy-efficient biofuel, according to Jerry Cherney, a professor of agriculture at Cornell University. In this news release, "Grass as Fuel," he says "Burning grass pellets makes sense; after all, it takes 70 days to grow a crop of grass for pellets, but it takes 70 million years to make fossil fuels." Unfortunately, there is anything like a grass political lobby in Washington, so he might not be heard. But with current oil prices, more and more people will be tempted to use cheaper -- and cleaner -- sources of energy. Read more...
Here is the introduction of the Cornell University news release.
Grow grass, not for fun but for fuel. Burning grass for energy has been a well-accepted technology in Europe for decades. But not in the United States.
Yet burning grass pellets as a biofuel is economical, energy-efficient, environmentally friendly and sustainable, says a Cornell University forage crop expert.
This alternative fuel easily could be produced and pelleted by farmers and burned in modified stoves built to burn wood pellets or corn, says Jerry Cherney, the E.V. Baker Professor of Agriculture. Burning grass pellets hasn't caught on in the United States, however, Cherney says, primarily because Washington has made no effort to support the technology with subsidies or research dollars.
Why is it important for environment?
Burning grass pellets makes sense; after all, it takes 70 days to grow a crop of grass for pellets, but it takes 70 million years to make fossil fuels," says Cherney, who notes that a grass-for-fuel crop could help supplement farmers' incomes.
Cherney points out that grass biofuel pellets are much better for the environment because they emit up to 90 percent less greenhouse gases than oil, coal and natural gas do. Furthermore, he says, grass is perennial, does not require fertilization and can be grown on marginal farmland.
Cherney recently presented his conclusions about grass biofuel at the Greenhouse Gases & Carbon Sequestration in Agriculture and Forestry conference, held March 21-24 in Baltimore.
You can find the abstract of his talk, "Grass Bioenergy in the Northeastern USA," on this page. Just scroll a little bit or search for Cherney on the page.
If you're interested in this subject, here is a link to the July 2004 issue of the "Dairy & Field Crops digest" (PDF format, 12 pages, 728KB). The article "Grass Management for Forage or Biofuel?" appears on pages 7 and 8.
In this article, Cherney argues that "grass is converted to useable heat at over 80% efficiency, with an energy output:input ratio exceeding 10:1, compared to other bioenergy sources with typicalsystem energy output:input ratios around 1:1."
The cost-effectiveness of pelletized grass as a fuel results from:
* efficient use of low cost marginal farmland for solar energy collection
* minimal fossil fuel input use in field production and energy conversion
* minimal biomass quality upgrading which limits energy loss from the feedstock
* efficient combustion in advanced yet modestly priced and simple to use devices
* replacement of expensive high-grade energyforms in space and water heating
Cherney is convincing, but it's hard to help him while living in Paris.
Sources: Cornell University News Service, March 31, 2005; and various websites
The way I get it, it's a zero-emissions fuel in that it's a closed carbon cycle. The CO2 from burning the plant or plant derivative will be consumed and used by another plant. This is assuming that no petroleum-based fertilizers, pesticides, etc. are used, which would release additional carbon byproducts that were locked beneath the ground before.
Great question. According to the article
So while grass may not be perfect, it is 90% better than what we've got, from a carbon-release standpoint.
Another consideration is that the carbon emitted from burning grass is carbon that the grass took out of our atmosphere while growing, so there would be no net increase in atmospheric carbon from its use. In contrast, carbon released by fossil fuels hasn't been in our atmosphere for millions of years, which is why re-releasing it into our atmosphere is problematic.
--- Attorneys Assisting Citizen-Soldiers & Families -
Carbon Dioxide emissions are really different, because the problem is greenhouse heating caused by increased carbon dioxide in the atmosphere. Burning oil and coal takes carbon that's been in the ground for a long time and pumps it into the atmosphere, which is a problem. But growing grass or trees for fuel takes carbon dioxide out of the atmosphere, using solar energy and chlorophyll to split it up into various plant compounds, so any carbon dioxide emissions you get from burning the grass are just moving around carbon dioxide you took out of the atmosphere last growing season, so it's no problem.
ObDoperReference: Hemp is a really good grass for applications like this. It grows fast, doesn't need pesticides, you can do useful things with the seeds, the fiber can be used for cloth if you don't feel like burning it, and as a bonus you get a bunch of flowers that you can divert to other applications.
Bill Stewart
New Fast-Compression-only CPR http://preview.tinyurl.com/dy575ks
> Don't alfalfa fields get 2 or 3 cuttings minimum
> per season?
Depends on the climate, among other things. Here in Wisconsin I get three cuttings a year of my mixed alfalfa/brome, but I am trying for an optimum combination of nutrition for horses, tonnage, and stand life. Many of my neighbor dairy farmers cut their pure alfalfa every 28 days. This gives them higher protein at the price of slightly lower tonnage and shorter stand life. If I was growing hay for fuel I would be trying to maximize dry weight without concern for nutritional value and would choose what to plant and how to harvest it on that basis.
Warning: this article may contain humor, sarcasm, parody, and perhaps even irony. Read at your own risk.
I've never heard of a plant absorbing organic material from the ground, unless you consider parasitic species such as heather and mistletoe that get glucose from their host plants (glucose, not simple carbon). I believe that a sessile organism that takes organic material from the ground as its main source of food can be described as a "fungus."
:).
In fact, this is why carbon 14 dating works - because the organic carbon present in all known lifeforms comes from CO2, which was converted to a fuel source by autotrophic plants. And on that note, I bid you all goodnight
America, most likely. Marijuana can cost up to $40USD/gram in certain cities, and the quality is often less then decent.
;)
In my home and native land however, the price for a Canadian citizen (American tourists sadly often get absolutly raped on prices when they come to visit) is just about $6-7USD/gram across the whole country. Prices drop exponentially for larger amounts, such as 1/4 of an ounce (7.5 grams if I remember right) will go for about $40-50(max)USD to a local. Quality in the main provinces is almost always excellent, and it's not terrible in our middle farmey ones either.
The more you know... the higher you'll go?
Enzymes are problematic because they're picky; the reason your body keeps its temperature so closely regulated (and a 5-10F/3-6C rise or fall in body temperature is so hugely significant) is because most enzymes care. A lot. Some, obviously, don't care so much if you bang on em a bit - plants', reptiles', and probably your termites. They still require reasonably controlled conditions pH-wise, because if that changes too much, your enzyme will fold up and crumple into something else entirely, and it won't work anymore. I am not personally that familiar with amylases, but just about any chemical reaction works much better in a solution, or in the gas-phase. Chewing away at a clump of fiber is tough.
As for sulfuric acid, well, that's pretty rough too. First of all, it's nasty stuff, and I don't think just anyone should be handling it on a daily basis. I know when I use it, I never slip on that gloves-and-goggles rule. Second, it's got some healthy energy requirements to manufacture - the process involves pressures of 2atm and temperatures of about 400C. Not to say it's impossible though, it's just got its own problems.
Ok, say you have your sugar monomer or dimer (sucrose, fructose, or glucose). We need to make it into alcohol. The easiest, and cheapest way, is yeast. You can probably get up to 15% with fancy osmotolerant yeasts. You probably won't do too much better with enzymes. Ain't gonna burn. So we're looking at distillation, which has its own substantial energy requirements. Not to say we can't do it, but it's trickier than just turning our garbage into ethanol- doing it with corn and sugarcane is hard enough.
I think it is more of a matter of how burning grass or any bio-fuel for that matter fits in with the carbon cycle. Burning of oil, coal and natural gas releases carbon that has been locked up underground for millions of years as opposed to grass which collects it from the air and thus isn't adding any more to current amounts.
I have successfully run a 1988 Citroen CX 25DTR on normal diesel fuel, heating oil, jet fuel, waste veg oil, waste hydraulic oil, and odd mixtures of these things. With the waste veg oil there was no smoke at all from the exhaust even under very heavy load at full power - and only a slight smell from the exhaust. It does *not* smell like greasy chips!
Sorry for the rant, but some statements are just stupid. More information can be found at Woods Hole Organic Geochemistry group ( http://dynatog.whoi.edu/ ), at the Newcastle U site ( http://nrg.ncl.ac.uk ) or on wikipedia ( http://en.wikipedia.org/wiki/Organic_geochemistry )