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4 Tons Of Plants per Mile to Ride In Your Car
Roland Piquepaille writes "As you might know, I enjoy big numbers. So it's just natural that I was attracted by this news release from the University of Utah, "Bad Mileage: 98 tons of plants per gallon." "A staggering 98 tons of prehistoric, buried plant material is required to produce each gallon of gasoline we burn in our cars, SUVs, trucks and other vehicles." For a reasonably efficient car, riding 25 miles per gallon, this translates to 4 tons of prehistoric plants per mile, or more than two tons per kilometer. The research paper also mentions that everyday, we are using the fossil fuel equivalent of all the plants growing during a whole year just for our cars. Even if these numbers are too large, this still makes you think about how inefficient our cars are. This analysis describes the calculations and contains other details about the research paper which will be published in November by Climate Change."
[Posted anonymously to avoid karma-whoring]
Bad Mileage: 98 tons of plants per gallon
Study shows vast amounts of 'buried sunshine' needed to fuel society
Oct. 27, 2003 - A staggering 98 tons of prehistoric, buried plant material - that's 196,000 pounds - is required to produce each gallon of gasoline we burn in our cars, SUVs, trucks and other vehicles, according to a study conducted at the University of Utah.
"Can you imagine loading 40 acres worth of wheat - stalks, roots and all - into the tank of your car or SUV every 20 miles?" asks ecologist Jeff Dukes, whose study will be published in the November issue of the journal Climatic Change.
But that's how much ancient plant matter had to be buried millions of years ago and converted by pressure, heat and time into oil to produce one gallon of gas, Dukes concluded.
Dukes also calculated that the amount of fossil fuel burned in a single year - 1997 was used in the study - totals 97 million billion pounds of carbon, which is equivalent to more than 400 times "all the plant matter that grows in the world in a year," including vast amounts of microscopic plant life in the oceans.
"Every day, people are using the fossil fuel equivalent of all the plant matter that grows on land and in the oceans over the course of a whole year," he adds.
In another calcultation, Dukes determined that "the amount of plants that went into the fossil fuels we burned since the Industrial Revolution began [in 1751] is equal to all the plants grown on Earth over 13,300 years."
Explaining why he conducted the study, Dukes wrote: "Fossil fuel consumption is widely recognized as unsustainable. However, there has been no attempt to calculate the amount of energy that was required to generate fossil fuels, (one way to quantify the 'unsustainability' of societal energy use)."
The study is titled "Burning Buried Sunshine: Human Consumption of Ancient Solar Energy." In it, Dukes conducted numerous calculations to determine how much plant matter buried millions of years ago was required to produce the oil, natural gas and coal consumed by modern society, which obtains 83 percent of its energy needs from fossil fuels.
"Fossil fuels developed from ancient deposits of organic material, and thus can be thought of as a vast store of solar energy" that was converted into plant matter by photosynthesis, he explains. "Using published biological, geochemical and industrial data, I estimated the amount of photosynthetically fixed and stored [by ancient plants] carbon that was required to form the coal, oil and gas that we are burning today."
Dukes conducted the study while working as a postdoctoral fellow in biology at the University of Utah. He now works for the Carnegie Institution of Washington's Department of Global Ecology on the campus of Stanford University in California.
How the calculations were done
To determine how much ancient plant matter it took to eventually produce modern fossil fuels, Dukes calculated how much of the carbon in the original vegetation was lost during each stage of the multiple-step processes that create oil, gas and coal.
He looked at the proportion of fossil fuel reserves derived from different ancient environments: coal that formed when ancient plants rotted in peat swamps; oil from tiny floating plants called phytoplankton that were deposited on ancient seafloors, river deltas and lakebeds; and natural gas from those and other prehistoric environments. Then he examined the efficiency at which prehistoric plants were converted by heat, pressure and time into peat or other carbon-rich sediments.
Next, Dukes analyzed the efficiency with which carbon-rich sediments were converted to coal, oil and natural gas. Then he studied the efficiency of extracting such deposits. During each of the above steps, he based his calculations on previously published studies.
The calculations showed that roughly one-eleventh of the carbon in the plants deposited in peat bogs ends up a
Here! Here! And another thing...I'm not convinced that water is made of two hydrogen atoms bonded to one oxygen atom. I mean, how do "THEY" know? They can't really see anything that small. I'll bet its really bananas and pistachio flavored ice cream. And how do I know the sun really exists? I can't see the nuclear fusion occurring deep within its core even though I can feel the byproducts of it everyday. That's it there is no sun! .... (and so goes the raving lunatic, muttering to himself as he wanders the sidewalks in the early morning)
Before you've made up your mind about an issue, go read about it for yourself. http://www.anwr.org/
Ethanol is more fuel efficient? How do you figure?
Might want to check here. Check last paragraph page 2 "Some critics say that ethanol contains less energy per unit volume than unblended gasoline. This is true."
Thank you, drive through.
Creating biofuel artificially would be much more efficient (in terms of biomass used) than the natural process of fossilization.