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4 Tons Of Plants per Mile to Ride In Your Car

Hemos posted more than 10 years ago | from the burning-'em-up dept.

Science 995

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."

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FIRST POST (-1, Offtopic)

Anonymous Coward | more than 10 years ago | (#7318781)

HAHAHAHAHHA

Re:FIRST POST (1, Insightful)

Del Lardo (683012) | more than 10 years ago | (#7318792)

25 mpg for a reasonable car!!!! Ah to live in the US where petrol is cheap and fuel economy doesn't matter.

Re:FIRST POST (-1)

Anonymous Coward | more than 10 years ago | (#7318863)

I know the feeling. I had to buy an imported car from outside the US to get 50+ MPG and good performance. Way to go Toyota Hybrids.

Site is slowing down - Article Text Below (-1, Redundant)

Anonymous Coward | more than 10 years ago | (#7318783)

[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 as coal, and that only one-10,750th of the carbon in plants deposited on ancient seafloors, deltas and lakebeds ends up as oil and natural gas.

Dukes then used these "recovery factors" to estimate how much ancient plant matter was needed to produce a given amount of fossil fuel. Dukes considers his calculations good estimates based on available data, but says that because fossil fuels were formed under a wide range of environmental conditions, each estimate is subject to a wide range of uncertainty.

Plants in your tank?

Dukes calculated ancient plant matter needed for a gallon of gasoline in metric units:

One gallon of oil weighs 3.26 kilograms. A gallon of oil produces up to 0.67 gallons of gasoline. So 3.26 kilograms for a gallon of oil divided by 0.67 gallons means that at least 4.87 kilograms of oil are needed to make a gallon of gasoline.

Oil is 85 percent carbon, so 0.85 times 4.87 kilograms equals 4.14 kilograms of carbon in the oil used to make a gallon of gasoline.

Since only about one-10,750th of the original carbon in ancient plant material actually ends up as oil, multiply 4.14 kilograms by 10,750 to get roughly 44,500 kilograms of carbon in ancient plant matter to make a gallon of gas.

About half of plant matter is carbon, so double the 44,500 kilograms to get 89,000 kilograms - or 89 metric tons - of ancient plant matter to make a gallon of gas. In U.S. units, that is equal to a bit more than 196,000 pounds or the equivalent of 3 CowboyNeals.
Dukes made similar calculations for oil, natural gas and coal to determine that it took 44 million billion kilograms (97 million billion pounds) of carbon in ancient plant matter to produce all the fossil fuel used in 1997. That includes 29 million billion kilograms of prehistoric plants to produce a year's worth of oil (including gasoline), almost 15 million billion kilograms of buried plant matter to make all the natural gas used in 1997, and 27,000 billion kilograms of dead plants to produce all the coal used in the same year.

"It took an incredible amount of plant matter to generate the fossil fuels we are using today," says Dukes. "The new contribution of this research is to enable us to picture just how inefficient and unsustainable fossil fuels are - inefficient in terms of the conversion of the original solar energy to fossil fuels. Fortunately, it is much more efficient to use modern energy sources like wind and solar. As the reasons keep piling up to switch away from fossil fuels, it is important that we develop these modern power sources as quickly as possible."

What about modern plant biomass?

Unlike the inefficiency of converting ancient plants to oil, natural gas and coal, modern plant "biomass" can provide energy more efficiently, either by burning it or converting into fuels like ethanol. So Dukes analyzed how much modern plant matter it would take to replace society's current consumption of fossil fuels.

He began with a United Nations estimate that the total energy content of all coal, oil and natural gas used worldwide in 1997 equaled 315,271 million billion joules (a unit of energy). He divided that by the typical value of heat produced when wood is burned: 20,000 joules per gram of dry wood. Huh-huh. Hey Beavis, he said "wood". Huh-huh. The result is that fossil fuel consumption in 1997 equaled the energy in 15.8 trillion kilograms of wood. Dukes multiplied that by 45 percent - the proportion of carbon in plant material - to calculate that fossil fuel consumption in 1997 equaled the energy in 7.1 trillion kilograms of carbon in plant matter.

Studies have estimated that all land plants today contain 56.4 trillion kilograms of carbon, but only 56 percent of that is above ground and could be harvested. So excluding roots, land plants thus contain 56 percent times 56.4, or 31.6 trillion kilograms of carbon.

Dukes then divided the 1997 fossil fuel use equivalent of 7.1 trillion kilograms of carbon in plant matter by 31.6 trillion kilograms now available in plants. He found we would need to harvest 22 percent of all land plants just to equal the fossil fuel energy used in 1997 - about a 50 percent increase over the amount of plants now removed or paved over each year.

"Relying totally on biomass for our power - using crop residues and quick-growing forests as fuel sources - would force us to dedicate a huge part of the landscape to growing these fuels," Dukes says. "It would have major environmental consequences. We would have to choose between our rain forests and our vehicles and appliances. Biomass burning can be part of the solution if we use agricultural wastes, but other technologies have to be a major part of the solution as well - things like wind and solar power."

Re:Site is slowing down - Article Text Below (-1, Offtopic)

kamukwam (652361) | more than 10 years ago | (#7318901)

In U.S. units, that is equal to a bit more than 196,000 pounds or the equivalent of 3 CowboyNeals .

Are you sure there is nothing wrong with your CopyPaste-skills?

Re:Site is slowing down - Article Text Below (-1)

Anonymous Coward | more than 10 years ago | (#7318903)

In U.S. units, that is equal to a bit more than 196,000 pounds or the equivalent of 3 CowboyNeals.

LOL.

Mmmmm... plants (-1)

Anonymous Coward | more than 10 years ago | (#7318784)

Err, wait a sec, I'm not a vegetarian.

First Post (-1, Offtopic)

Anonymous Coward | more than 10 years ago | (#7318787)

Another reason to fund fuel cell research, methinks

so give them up (-1)

Anonymous Coward | more than 10 years ago | (#7318793)

So, when are you going to give up your car?

Re:so give them up (0, Offtopic)

Biff98 (633281) | more than 10 years ago | (#7318828)

The day Bill Gates says Windows sucks and Linux is really the way to go.

say no to cars? (4, Funny)

QEDog (610238) | more than 10 years ago | (#7318795)

Reminds me of an article posted in /. before that said:

"Building more roads to combat traffic congestion is like buying a bigger belt to combat obesity"

burgers (4, Interesting)

matticus (93537) | more than 10 years ago | (#7318796)

and every time I eat a burger, 2 tons of modern plants died to make that cow (or something like that).
We all know the cars burn too much energy. how long of a period were plants compressed for oil? thus, how long until we run out?

Forget the bun... (-1)

Anonymous Coward | more than 10 years ago | (#7318913)

Eat at Taco Bell and make your own damn gas...

Re:burgers (3, Informative)

Anonymous Coward | more than 10 years ago | (#7318937)

I think the artical is misleading. Not all of the plant is converted to oil only a small part. This is intuitive, becouse your car dosen't carry 52 tons of gas in its tank. Also, gas is one of the best ways to back that much energy in to a small space.
-James

you assume (2, Insightful)

Anonymous Coward | more than 10 years ago | (#7318797)

That plant material is the source of the oil reserves. I do not think there were ever enough plant mass ever to give us the amount of oil we have presently. FP

Re:you assume (2, Informative)

Anonymous Coward | more than 10 years ago | (#7318858)

That plant material is the source of the oil reserves. I do not think there were ever enough plant mass ever to give us the amount of oil we have presently. FP

Well, it might be that oil didn't just come from bio-matter, but from ancient geological processes during earth's formation/early evolution. At least, that is what the Soviet's believed, and they seemed to have lots of oil.

Re:you assume (3, Informative)

wa5ter (628478) | more than 10 years ago | (#7318864)

What are you suggesting? There is no shortage of clear proof that this is where the oil comes from. Coal contains clearly fossilised plant material.. oil and coal and natural gas are often all found together. The process of generating them can be simulated very easily.

Well -- yeah, Are you just figuring this out? (3, Insightful)

Biff98 (633281) | more than 10 years ago | (#7318804)

Internal combustion engines have ALWAYS been inefficient. There have been attempts to make them more efficient, but there has NEVER been an engine based on gasoline that has exceeded even 35%. Even rotary engines are very poor producers of energy to a set of tires. Just the facts of life.

Anyone for Hydrogen?

Hydrogen-powered cars (-1)

Anonymous Coward | more than 10 years ago | (#7318888)

That's all we need: a bunch of baby Hindenbergs hitting the freeways.

And we thought the Pinto was dangerous!?!?

Re:Well -- yeah, Are you just figuring this out? (1)

djh101010 (656795) | more than 10 years ago | (#7318914)

Yay hydrogen.

Oh - one thing...how are you planning to produce your hydrogen? Can't mine it - can't make a well to find it - gotta generate it by reforming another hydrocarbon (read: fuel) or by hydrolysis of water (read: takes fuel).

Other than those inconvenient facts, it's a great idea. How about biofuels instead - veggie oil runs diesel engines quite happily, for instance, and we've got plenty of excess capacity to grow the soybeans for it.

Re:Well -- yeah, Are you just figuring this out? (0, Troll)

PhysicsExpert (665793) | more than 10 years ago | (#7318924)

Exactly, any engine that relies on the carnot cycle is going to be inefficient, it is just one of those facts of life. Hopefully we will not have to rely on gasoline for much longer.

Interestingly although hydrogen fuel cells are an excellent choice for powering small vehicles, it is unlikely that they could be made powerful enough for trucks and even large SUV's and so another solution will have to be found. Some of the possibilities include LPG or bitumen based engines but perhaps the biggest hope is for ion drives similar to the ones currently being tested on Norwegian buses.

They are ideal in that they are practically silent and have no moving parts so they will almost never go wrong. Currently there is an environmental risk as they emit dangerous cl- ions but it is hoped that by adding h+ ions at the exhaust stage these can mopped up.

If I remember correctly Ford is building an ion drive based dragster to compete at the high speed trials in May next year. It should be very interesting to see how it stacks up against conventional NOx based machines.

oil and petrolium (2, Informative)

elrick_the_brave (160509) | more than 10 years ago | (#7318805)

Hmm.. I've always wondered if we'd run out of oil (reasonably priced.. when the price is fixed) in my lifetime... some say yes... I really don't care about having a car.. it's convenient... but I do care about plastics and other poly-things that we get from oil-based resources... how long could humanity go without?

Re:oil and petrolium (1, Insightful)

Anonymous Coward | more than 10 years ago | (#7318852)

You don't need pretroleum for plastics just like you don't need pretoleum for heat. It just happens to be conveninent and for the time being it's the cheapest option. That last part is what keeps us using petroleum and prevents us from using nuclear --cost. Solar and geothermal will eventually be used as the sources for most energy for the same reason --costs. When you break it down, it's all about heat, you can't get chaper heat than heat itself and solar and geothermal go straight to the hear. Okay, maybe fusion. But still, heat is what it's all about.

Re:oil and petrolium (1)

tomcio.s (455520) | more than 10 years ago | (#7318878)

Seeing how plastics are relatively new phenomena, I'd say we can do away with them without much trouble in the first place.

Sure they are nice and convenient, but in all reality, for human life to continue, we don't need them.

Just my $.02

Re:oil and petrolium (1)

GTRacer (234395) | more than 10 years ago | (#7318956)

True dat, BUT...

How much would the average lifespan be affected if plastics and their uses were dropped overnight? What would we use to make our things? And how long until THAT ran out?

What about the uses of plastics for packaging, sanitation, sterile handling, etc.? What kind of effect would not using plastics have on healthcare? Back to glass hypos? JCAHO safety regs be damned, then!

What about the economics? Plastics (and related polymers) make a lot of things lighter or stronger. Sure, there are metallic ways to do this, but how much more would things cost to make and purchase?

And speaking of money, what would they make the anti-counterfeiting strip in the new bills with? ;)

GTRacer
- Believes plastics are polymerrific, not a member of the Plastics Council

what (0)

Anonymous Coward | more than 10 years ago | (#7318807)

still makes you think about how inefficient our cars are.

I think its more like how inefficient mother nature is. Geez lady, can't you just spit out hydrogen?

inefficient!!!!???? (0)

Madcapjack (635982) | more than 10 years ago | (#7318810)

98 tons of plant material for c.a. 25 miles? Damn! Have you seen a pound of carrots pushing any vehicle a foot?

reasonably efficient? (4, Insightful)

ratbag (65209) | more than 10 years ago | (#7318812)

25 miles per gallon is many things, but reasonably efficient isn't one of them.

Rob.

Re:reasonably efficient? (1)

PaulGrimshaw (605950) | more than 10 years ago | (#7318908)

From a soccer website of all things:

"2/ Average MPG for a 1.6 litre 'family' car. This figure (33.5mpg) has been taken from the RAC and is based on both urban and motorway driving in a loaded car i.e. More than one occupant."

Thats 33.5 average.. be interested to know what it is in the US... Paul.

Re:reasonably efficient? (1, Interesting)

Zocalo (252965) | more than 10 years ago | (#7318927)

Ahh, but this is US centric Slashdot, and in the US the average car is actually a four tonne SUV I gather. Jokes aside, I get over 30 miles per gallon urban mileage in my 6 cylinder, 2.5l BMW and over 50mpg extra-urban. 25mpg is not what I'd call "reasonably efficient" either, it's what I'd call "crap".

Isn't most of the original mass water? (4, Insightful)

YetAnotherAnonymousC (594097) | more than 10 years ago | (#7318813)

Isn't most of the original biomass water that does not end up in the oil/coal/gas deposits? Or am I missing something.

I just don't quite see the point of the guy who did the calculations/report... and I did read the article. This is just throwing around big meaningless numbers. At least Ig Nobel candidate material is train-wreck-interesting.

Re:Isn't most of the original mass water? (3, Insightful)

andykuan (522434) | more than 10 years ago | (#7318940)

Well here are some percent water composition numbers for various fruits and veggies from a Virginia Farm Bureau article [vafb.com].

Let's say plants are 75% water (probably a bit high, but I'm being conservative here). That 4 tons of wet-weight per mile becomes 1 ton of wet-weight per mile. It's all in the same order of magnitude. 2000 pounds of dried spinach to push my car 1 mile is still a lot of plant matter.

Anyway, I think the point of this calculation is similar to the point being made by those illustrative lessons (say, in Time Magazine) about how many miles high a trillion dollars in debt would be if we stacked 1 dollar bills, or how many miles of muscle we have in our body, or the number of land mines per person have been buried in Korea. It just offers a different perspective.

What is the equivelent in...... (0)

Anonymous Coward | more than 10 years ago | (#7318814)

Ok... lessee... 98 tons of plants/gallon... hmmm... I'll bet that we could get more efficient energy extraction from flannel-clad, tree-hugging lesbians (not that there's anything wrong that).

how many dead babies to fuel your leased SUV? (-1)

Anonymous Coward | more than 10 years ago | (#7318815)

it just doesn't add up. get ready to see the light.

Inefficient? (5, Funny)

jeffkjo1 (663413) | more than 10 years ago | (#7318818)

Even if these numbers are too large, this still makes you think about how inefficient our cars are.

I think it shows how inefficient mother nature is. Stupid nature, not forseeing our need to drive Hummers and Ford Excursions!

How about free fuel? (1)

ProppaT (557551) | more than 10 years ago | (#7318819)

Hmm, so I could burn 4 tons of plants per mile to drive my gas truck....OR I could go to McDonalds, have them dump out their fry oil into my bio-diesel truck for free and get about 50mpg.


Silly humans...

Come on, get reasonable! (0)

Anonymous Coward | more than 10 years ago | (#7318824)

25 mpg for a *reasonably* efficient car??!!!

I normally get around 45 mpg in my car, which is just a bog standard Vauxhall Astra, nothing particularly fuel efficient.

Good heavens, the wonders having a heavy fuel-tax will force car manufacturers to...

What's the point here? (5, Insightful)

AnhZone (139289) | more than 10 years ago | (#7318825)

Why do we care about prehistoric plants that turned into underground petrochemical deposits millions for years ago. I agree that cars are ridiculously inefficient, but underground oil is not one of the natural features I am worried about being disturbed. Above-ground pollution, oil spills, global warming, yes, but why cry for rotten prehistoric plants?

John

Re:What's the point here? (1)

acid_zebra (552109) | more than 10 years ago | (#7318935)

One day my friend, we are going to run out of rotten prehistoric plants. This article is intended to show that we are going through them VERY fast (yes, we knew already, but some bitheads like numbers, go figure)

And then plenty of people will be crying for them rotten prehistoric plants.

Better than that (4, Insightful)

cybercuzco (100904) | more than 10 years ago | (#7318827)

this still makes you think about how inefficient our cars are.

Its even better than that! Internal combustion engines are only about 25% efficient, so for every ten gallons of gas you put into your car, only 2.5 gallons are actually used to propel you forward, the rest is just used to heat up the engine and exhaust.

Re:Better than that (1)

JanneM (7445) | more than 10 years ago | (#7318899)

Not even that. Out of that energy, a good deal turns into losses elsewhere, like transmission and gearbox (stuff you can do without with for instance electric motors). I believe the 'real' number is closer to 15%.

Thank goodness for research like this (3, Funny)

TopShelf (92521) | more than 10 years ago | (#7318829)

That certainly explains the foul smell I can't get out of the seats...

What about thermal depolymerization? (5, Interesting)

Xiver (13712) | more than 10 years ago | (#7318830)

I read an interesting article at Discover.com [discover.com]. Technological savvy could turn 600 million tons of turkey guts and other waste into 4 billion barrels of light Texas crude each year.

I think this is a huge step in the right direction, I'll be very interested to see what happens once the plant is online.

Re:What about thermal depolymerization? (-1)

happyfrogcow (708359) | more than 10 years ago | (#7318886)

GW Bush is a turkey. I'd call him other things but a turkey will suffice. If you squeeze him, how many barrels of oil will you get?

Comparisons? (3, Interesting)

confu2000 (245635) | more than 10 years ago | (#7318833)

Anyone want to take a stab at how much a horse eats per mile? I guess to be fair, you'd probably want to multiply it by 4 at least. Even then it's only 4 horsepower versus like 100-150 in your standard economy car.

Re:Comparisons? (1)

lennart78 (515598) | more than 10 years ago | (#7318884)

The fact that 'your standard economy car' is able to generate 100 - 150 Horsepower does not mean it actually /does/.
The french Citroen 2CV is/was a lightweight car that could get you from a to b with a 2 Horsepower engine. No, it didn't have SIPS, rollbars and heavy steel plating like todays cars, but it makes you wonder if you actually /need/ all that power to get where you need to be...

How much gas does that give us? (3, Informative)

Wyatt Earp (1029) | more than 10 years ago | (#7318835)

"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."

If there's 600,000,000 of plants and plant material out there to burn in fossil fuels...and we burn a years worth of it a day. And you divide 600 million by 365...that gives us 1643835 years worth of fossil fuels.

A much more optomistic projection that even the Skeptical Environmentalist!

I'm going to go drive my 5.7 liter Chevy truck around then just for the hell of it.

Re:How much gas does that give us? (0)

Anonymous Coward | more than 10 years ago | (#7318920)

If there's 600,000,000 of plants and plant material out there to burn in fossil fuels...and we burn a years worth of it a day. And you divide 600 million by 365...that gives us 1643835 years worth of fossil fuels.

I was about to say the same thing.

I'm going to go drive my 5.7 liter Chevy truck around then just for the hell of it.

Why don't you replace the 350 with a 502 instead? That'll rankle the slashbots, big time.

What are the energy costs of bicycling? (1, Insightful)

cosmol (143886) | more than 10 years ago | (#7318838)

Wouldn't it be interesting to see how much bio material is needed to give a person energy to pedal a bicycle for a mile. Methinks that it would be in the order of grams rather than tons.

Athlons and Pentiums (2, Funny)

Brento (26177) | more than 10 years ago | (#7318839)

In a related story, the University of Utah pointed out that modern desktop computer processes consume roughly 14 tons per hour of running SETI, a popular screen saver. "At some point, you have to wonder just how important it is to find alien life," said Professor Ima T. Hugger, "when you're killing so much life here on our own planet just to find out. One little green man simply isn't worth twenty redwood trees - try shutting down your machine once in a while, or switch to that nice screen saver with the rotating Windows logo."

When asked about the energy required to create his polyester pants, Hugger refused comment.

Inefficiency? (4, Insightful)

worst_name_ever (633374) | more than 10 years ago | (#7318841)

Even if these numbers are too large, this still makes you think about how inefficient our cars are.

I agree that regular gas-powered cars could be made more efficient, but don't the numbers above point more towards the "inefficiency" of the prehistoric plants --> crude oil deposits process?

If it *is* plants (5, Interesting)

HarveyBirdman (627248) | more than 10 years ago | (#7318847)

There's an idea that some oil comes from deeper sources, and has an abiogeneic origin. There are hundreds of wells drilled more than 5 km deep, below the levels of prehistoric plants (what is called "basement rock"), and they are still productive.

Here's a starter link: Link [cornell.edu]

Does it say (4, Insightful)

Kohath (38547) | more than 10 years ago | (#7318848)

Does it say how many tons of plants have existed in the last billion years or so?

I bet it's a lot.

Hybrid Car (2, Interesting)

kacp (188529) | more than 10 years ago | (#7318851)

I just bought a Honda Civic Hybrid, and yes I'm getting the 40-odd MPG. It does so by basicly recycling the enegry expelled. Rather than lose energy in normal cruising conditions and breaking, it stores it in the battery for future use. You use the energy from the battery to power the engine, and you recover a bit of that back.

I know that it still uses gas as its primary source, and that due to thermodynamics I'm never going to be able to recycle all the energy, but the system, I think, is a step to making cars more efficent.

Now, if only Detroit would make such a car, but that's another topic...

Large numbers (1)

Manos Batsis (608014) | more than 10 years ago | (#7318854)

Even if these numbers are too large, this still makes you think about how inefficient our cars are.

Actually I've been wondering how can all these tons of oil can even exist underground. The whole process under which oil is generated, makes the picture impossible IMHO.

It's just a conspiracy I say. Bring in the hydrogen.

What's the Problem? (1)

clinko (232501) | more than 10 years ago | (#7318855)

I don't see a problem here. Plants aren't that big, and i'm sure humans are worth more in fuel than a few plants.

So the few people that survive will have plenty of dead humans to use with the amount of polution we use...

The inefficient thing is... (1)

jcrash (516507) | more than 10 years ago | (#7318856)

Even if these numbers are too large, this still makes you think about how inefficient our cars are.

I think the inefficient part in the process is the break down of the plant into hydrocarbons. One gallon of gas comes from just a few gallons of oil. So, the weak link isn't the car.

not so sure (1)

happyfrogcow (708359) | more than 10 years ago | (#7318857)

a few years ago, my thermodynamics professor at ohio state who was very in to the debate on the "oil crisis" we are in, bluntly stated that it was not this prehistoric biodegrading plant/animal matter that created oil. Since I can't remember his name or website, this isn't much use.

Re:not so sure (1)

happyfrogcow (708359) | more than 10 years ago | (#7318958)

ah, found it and take it half back. it was just decaying animal matter. Plants yes. Read section 2
http://rclsgi.eng.ohio-state.edu/~korpela/opmat alk .pdf

Fuel efficiency... (1)

Code-Ex (655722) | more than 10 years ago | (#7318860)

"My car gets fourty rods to the hogs head and that's the way I likes it." - Grandpa Simpson

oil bad (1)

bananaape (542919) | more than 10 years ago | (#7318861)

Perhaps yet another reason to move away from oil based car engines.

One gallon of oil weighs 3.26 kilograms.
Last time I checked, kilograms were a measure of mass, not weight.

only about one-10,750th of the original carbon in ancient plant material actually ends up as oil
The rest of it has to go somewhere. Coal maybe? It just doesn't disappear.

I would like a little more basis from where he pulled these numbers.

For metric system addicts: (2, Informative)

Anonymous Coward | more than 10 years ago | (#7318862)

25 mpg [google.com]

So what? (0)

Anonymous Coward | more than 10 years ago | (#7318872)

So it takes 98 tons of biomass to make a gallon of gas. What happens to the rest?

About half of a gallon of crude oil can be made into gas. The rest is made into kerosene, deisel oil, motor oil, asphalt, plastics, and other stuff. Basically all of any gallon of oil extracted is made into something useful.

The other 97.99 tons never leaves the ground. Its not as if we chopped down 98 tons of living trees. The plants are gone, and the oil is there, whether we use it or not. This doesn't show our inefficiency at using plants, but Nature's inefficiency at making oil out of plants.

UH, one thing (1)

argoff (142580) | more than 10 years ago | (#7318874)

INAG (I am not a geologist) but my understanding is that the theory that oil came from old plants and animals is today considered wrong. Instead it is produced by ultra high temperature bacteria energized by heat from the earths core.

PS, if you really care about the environment - go nuclear

PSS, that is not a troll

How many tons of hydrogen (0)

wowbagger (69688) | more than 10 years ago | (#7318875)

OK, so how many tons of hydrogen had to be fused in order to make a gallon of gas - don't forget that fusion is not 100% effecient, so it takes many kilotons of hydrogen to make a ton of carbon (the rest being pissed off as heat, as helium/lithium, etc).

Also factor in the tons of carbon that never leave the star that made it. /bullshit mode off

Now, what does ANY OF THIS have to do with ANYTHING?

OK, you want to critize our current usage of mineral oil vs. making biodiesel, great. But let's try to compare apples with some form of fruit, not compare apples to rocks!

Re:How many tons of hydrogen (4, Interesting)

tbone1 (309237) | more than 10 years ago | (#7318900)

Not only that, but how much land would be opened up to agriculture if all our fuel came from crops? Would forests be leveled, swamps drained, topsoil eroded, etc?

Everything comes at a prices, monetary or otherwise. Most environmentalists (or at least, journalists writing on environmentalism) don't seem to grasp this.

This isn't just about inefficiency of cars. (4, Insightful)

Derek Pomery (2028) | more than 10 years ago | (#7318883)

But also about inefficiency of natural fossil fuels.
Key Fact.
Since only about one-10,750th of the original carbon in ancient plant material actually ends up as oil, multiply 4.14 kilograms by 10,750 to get roughly 44,500 kilograms of carbon in ancient plant matter to make a gallon of gas.

google cache of old-news biofuel breakthrough [216.239.41.104]

Note they are claiming they can eliminate dependance on oil importation with agricultural waste alone. No other cultivation necessary.
And the point is. Once we use the biofuels, we are in the carbon cycle. No more pumping carbon out of the earth.

use biodiesel (1, Interesting)

Anonymous Coward | more than 10 years ago | (#7318885)

Typically I bike commute, but when I need to drive I use my car which runs on biodiesel (it is a VW Jetta TDI).

Biodiesel is produced from vegetable oil crops such as soy or canola. It is also currently being produced using waste vegetable oil (mostly frier oil from fast food resturants). There is research showing that algae crops would be an even more effective crop for producing the fuel. 1 acre of cropland produces about 100 gallons of fuel currently. My car gets about 40 miles to the gallon for city driving (50 on the highway) too.

burn the bean!

1 day of cars = 1 year of plants (2, Insightful)

Saint Stephen (19450) | more than 10 years ago | (#7318887)

Gee, that means 1,000,000 years of plants will only last us 2,737 years! And we all know the prehistoric period wasn't measured in hundreds of millions of years!

[For the record, I support Hydrogen so we can tell the Arabs and Environmentists to go jump in a lake and quit bugging me.]

fat=inefficiency (1, Funny)

Madcapjack (635982) | more than 10 years ago | (#7318889)

someone ought to calculate the increase in fuel efficiency we'd gain in the U.S. if we weren't a nation of over-weight Big Mac eaters.

Prehistoric Plants? (2, Interesting)

phorm (591458) | more than 10 years ago | (#7318893)

While I do agree that currently vehicles are inefficient and that we are eventually heading towards insufficiencies in our supplies of fossil-fuel, one must also consider the vegetation of the eras that became the fossil fuels of today. From what I can gather, many plants were rather humongous in comparison to today. I mean, if say during the period of dinosaurs, plants had to be big enough to feed a pod of 10-15 meter behemoths, I'd say we had a lot of vegetation going at that time. Forget how many plants it takes to power a car, how much did it take to fuel a dinosaur?

And besides, aren't fossil-fuels the product of not only plants, but animal-life as well? I could be wrong on this one, but I think everything was part of the good ol' life-to-petrol cycle.

NO WONDER THE THOSE DINOS DIED!! (-1)

Anonymous Coward | more than 10 years ago | (#7318894)

We stole all their food.... from the future.... think on that for a moment.

Lets say the internet (or rather the machines that constitute it) runs on 99% fossil fuel (a few hydro and solar puppies about, but not many)....I want to know how many tons of "ye olde" plant matter per second the internet eats. How many saplings just to deliver this page to you now?

One of my projects for the future (which has been done numerous times) is to take a mini-itx or nano-itx board, hub, modem etc (my network bar my desktop) and run it off solar. More people should be doing this.... there needs to be an alliance between eco and tech soon or else there will be toasty futures.

Our children and their children are going to inherit enough problems as it is, the least we can do is not make it uncomfortably hot (even in winter) while they are dealing with the capitalist globalised geopolitical terroristic war-torn famine and disease ridden mess we are going to leave them with.

Re:NO WONDER THE THOSE DINOS DIED!! (0)

Anonymous Coward | more than 10 years ago | (#7318948)

on a side note; I am sure (when it is caculated, and it will be) I could probably drive around Australia a couple of times with the energy that has been expended on "first posts" - and useless N.Bs like this one.

And I thought (2, Funny)

OverlordQ (264228) | more than 10 years ago | (#7318902)

rods to the hogshead was bad enough, now we got Plant ton/(km|mi)!? WHEN WILL IT END!?

Big surprise. (1)

Feren (97175) | more than 10 years ago | (#7318905)

Yep, our cars are inefficient. You know it, I know it, your neighbor's pet cat knows it. Some cars (SUVs) are much worse than others... but even if you buy a Dodge Colt that can get 45 miles per gallon on the highway you've still got an engine that's simply not realizing maximum efficiency. I for one would welcome a better solution -- something a great deal more fuel-efficient, more environment friendly and less costly to maintain (Oil changes are expensive).

But what is the point of this article? So our vehicles utilize a material that took a monumental amount of material over a monumental timeline to create. The supercar we keep waiting for hasn't arrived yet (I wouldn't mind flying around like George Jetson, complete with crazy sound effect) so what exactly are we supposed to do beyond what we already do (carpooling, not buying Hummer H2s, etc)?

Time for Biodiesel? (0)

Anonymous Coward | more than 10 years ago | (#7318906)

Atleast it should keep the proportion straight,
apart from protecting the precious fossil fuel
for our future generation. Think about a
small blender sized apparatus that could make
diesel(bio) on demand. It could be a killer!.

Auto fuel (1)

germinatoras (465782) | more than 10 years ago | (#7318907)

I don't know what you guys are talking about. My car runs on Oxygen, which is produced all the time by plants around the world.
Sure, it uses some kind of fossil fuel to catalyze a chemical reaction, but it's oxygen that spins the flywheel.
If fossil fuels get depleted, that's a very bad thing - but there's always plenty of oxygen. All we need to do is find a different catalyst.
(don't believe me? Look under your hood - you'll be surprised to learn that your "gas pedal" is not controlling the amount of gas going into
your cylindars, but it's regulating the amount of air flowing through the intake manifold. It's an Oxygen pedal, not a gas pedal.)

So? (2, Interesting)

SlamMan (221834) | more than 10 years ago | (#7318912)

What's the big deal? Its not like this 4 tons of dead plants are doing anything else if I'm not using it.

More Perspective (0)

jimi1283 (699887) | more than 10 years ago | (#7318917)

Even if this was way overestimated, 1 years worth of plants per day is a tiny amount when figured over the hundreds of millions of years of prehistoric plants that ever were. 365 years worth of plants used per year is a paltry sum when viewed in the right perspective.

To be fair to our cars (1)

Illserve (56215) | more than 10 years ago | (#7318925)

This figure incorporates the added inefficiency of the process that converted plants -> oil. That was probably a very lossy process.

Welcome to pseudo-science (1)

n1ywb (555767) | more than 10 years ago | (#7318926)

I hate fossil fuels. I build solar cars. But this study has played some games to get hugely inflated numbers.

The crux of his "theory" is that only one-10,000th of the ancient dead plankton carbon that got deposited on the seafloor got turned into oil. He considers the other 9,999-10,000ths to be waste, or something.

From a more logical viewpoint, all that other carbon that didn't wind up as oil is completely irrelevant to anything and everthing. It shouldn't even be considered in the equation. It still sits underground in some form, we haven't affected it in the slightest by pumping out oil. So how can it be considered "waste"?

Since only about one-10,750th of the original carbon in ancient plant material actually ends up as oil, multiply 4.14 kilograms by 10,750 to get roughly 44,500 kilograms of carbon in ancient plant matter to make a gallon of gas


NO!!! The carbon matter that wound up NOT as oil simply LEFT THE BUILDING! It had NO EFFECT whatsoever on the carbon matter that DID become oil. It's not like the non-oil-producing carbon got CONSUMED or something, IT'S STILL THERE UNTOUCHED. They are two separate and distinct groups of carbon matter.

The rest of his equation seems plausible.

One word: bioethanol (4, Insightful)

Fnkmaster (89084) | more than 10 years ago | (#7318928)

That's right, there are great solutions out there that are far more efficient. But the unfortunate reality right now is that the economics of pumping shit out of the ground is very, very hard to compete with. The cost basis of oil (formed mostly by transportation, corruption and cronyism) vs. any harvested biological feedstocks used to make ethanol or biodiesel may be closer to competitive these days, but it's unlikely that the harvested feedstocks will ever win out by a large enough margin to encourage the capital investment necessary to switch over the huge established infrastructure without substantial government intervention.


No, I'm not talking about corn ethanol here, so please stop the silly arguments about how ethanol is inefficient - making it from corn is just silly. There are lots of cheap, far more easily harvested cellose-based plant products that can be broken down with slightly more effort into ethanol, and could provide us with a cheap, plentiful, and substantially more efficient means of storing and transporting biological energy to power our big ole' gas guzzlers.


This is a substantially more realistic and cost effective solution than hydrogen, and it doesn't require us to build massive amounts of new infrastructure (just a limited number of bioethanol plants) or a totally new kind of transportation and distribution network to handle hydrogen. Ethanol is stable, easy to transport, and holds up quite well to most abuse (well, except the drinking kind). It still takes a lot of cellosic material to make a gallon of bioethanol, but it's a lot less than went into that gallon of gas - it's just that the input of biological material happens in the here and now instead of millions of years ago - so we have to bear the cost ourselves. But it's renewable, predictable, and would remove the sick political imperatives behind the distribution and availability of fossil fuels. As an added bonus, no more terrorists.

In other news (1)

onyxruby (118189) | more than 10 years ago | (#7318938)

Human eat large quantities of food each year as well. All those hamburgers we eat come from cows that have to eat grass you know. Even worse if your a vegetarian, for then you eat only vegtables, and those require a lot of space.

Not only that but some of those culinary delights you call dinner require foodstuffs from several continents. This requires that planes, ships, trane and trucks all be in operation to support this thing you call dinner.

And all those vehicles require things too you know. Just try and get a vehicle that doesn't use parts from several continents. All those parts require factories, and they require electricity. Electricity requires source material like coal and natural gas. Those also come from long dead plants.

Face it you can't win! You cannot exist on this planet without consuming things, it's called the cycle of life. Your going to use resources regardless, so go drive somewhere, have a nice dinner, and remember that someday you too will end up in somebodies gas tank.

Now can someone please explain to me why I'm supposed to feel guilty for exploiting the long dead biomass of a bacteria, plants and dinosaurs?

How inefficient cars are? (1)

Performer Guy (69820) | more than 10 years ago | (#7318943)

Makes me think how inefficient trees are at making gas more than how inefficient cars are at burning it.

Oil doesn't come from plants. (1)

computersareevil (244846) | more than 10 years ago | (#7318944)

This article is baloney. The current thoery is that most oil was created during the formation of the planet or shortly thereafter, and does NOT come from plants/animals/whatever. So we are burning a totally non-renewable energy source.

And so what? The computers will take over the earth and kill us all long before we run out of gas.

Walking (1)

isa-kuruption (317695) | more than 10 years ago | (#7318945)

I hear walking is much more efficient. You can walk a mile on only a small meal, prob the equivalent of 1/2lb of vegatables. This, of course, makes it more efficient.

Of course, if you have a 60 mile commute like I do, I'd need to eat about 30lbs of vegatables.... as well as allow approximately 12 hours of commute to walk those 60 miles. Which means I would have to leave for home the second I get to work in order to leave in time to get to work ontime the next day. Oh boy...

everything wastes energy (0)

Anonymous Coward | more than 10 years ago | (#7318949)

The sun burns away trillions of tons of hydrogen every second. Human bodies are only able to convert about 25% of food to energy. Somehow the world continues to exist. If we could get 100% energy or even close to it out of anything a cup of coffee could probably power the US for a year.

Could you use International Standards please? (1)

Slowleggs (604433) | more than 10 years ago | (#7318950)

I'd rather have litre than gallons, and kilometer or real mile ( = 10 kilometer) than your old 'miles'. I know it's hard to change your ways, but please, I should not have to learn the old 'empire' standards too?

The REAL inefficiency... (1)

insensitive_clod (613304) | more than 10 years ago | (#7318953)

The real inefficiency is the conversion of biomass to fossil fuel. 98 tons only makes 1 gallon of gas? If took 98 tons of biomass now and used it to produce methane for fuel, we'd do a hell of a lot better than the equivalent of one gallon of gas.

Our gasoline powered cars may not be efficient, but the fact that 98 tons=1 gallon seems pretty irrelevant.

We're the top of the food chain (1)

sammyo (166904) | more than 10 years ago | (#7318957)

Isn't this just implied by being a the top of the 'pyramid'? So how many 'trees' does the average wolf consume in a year? Maybe it will help if we stop the wolves from eating meat?

Yes this is a troll.

But a troll against fuzzy statistics.

If only..... (1)

FrostyWheaton (263146) | more than 10 years ago | (#7318964)

The big three automakers would stop covering up the REVOLUTIONARY SUPER CARBURETOR that I read about in the back of Popular Science, we could get that number down to 1pptpm (Pre-historic Plant Ton per Mile)
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