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Are we really running out of fossil fuels?

  1. Jul 13, 2014 #1
    Just wondering if it's true when people say we will be out of oil in 50 years. If so are there plans to what's gonna happen?
    Any answers are appreciated, thanks.
  2. jcsd
  3. Jul 13, 2014 #2

    Simon Bridge

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    Welcome to PF;
    It is true that fossil fuels are running out.
    50 years may be a bit soon.

    So far there are no cohesive plans for what is going to happen - but there are a lot of ideas.
    It's what all those "alternative fuel" things are about, but basically nobody can agree on what to do.

    Probably the clearest articulation of the problem is here:

    ... see all eight.

    The long historical perspective is useful:
    ... look through the timeline to see how far back governments started regulating resources due to pollution and scarcity concerns.
    Last edited by a moderator: Sep 25, 2014
  4. Jul 13, 2014 #3
    This is really cool, I'll be sure to give this a read and watch the video.
    And thanks of the welcoming.
    Last edited by a moderator: Sep 25, 2014
  5. Jul 13, 2014 #4


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    The phase "running out" is ambiguous, covering multiple topics of supply, consumption, rate of production, alternatives, etc, so try breaking down the ambiguous question into many specific ones. Are fossil fuels finite? Yes, of course. How much of each type? Again, ambiguous. There are multiple figures covering known, explored deposits and also "technically" recoverable deposits which don't count all the fossil fuel molecules in the ground but only those likely to be removable with the economics of existing technology. On and on, giving answers of 20 to 250 years depending on the estimated size of the deposits, the type of fuel and rate of consumption. Is the world likely to actually to completely deplete all stores of fossil fuels? If history is any guide, no. Alternatives arise, and consumption does not always stay on trend. In the US at least, oil consumption is generally on the decline since 2005, though global consumption still increases.

    See the alternatives, which seems to be the main lesson from history. Bronze replaced stone tools, coal replaced wood, fossil oil replaced whale oil, glass fiber supplanted copper. Neither wood nor whales nor copper are depleted. In the US, corn ethanol now supplies roughly one million barrels per day of US liquid fuels by volume, or more than 10% of US domestic crude oil production, even though corn is a relatively poor energy crop.
    Last edited: Jul 13, 2014
  6. Jul 13, 2014 #5


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    My favorite story about projecting technology trends into the future is the prediction made sometime around the end of the 1800's which said that given the increasing population growth and the slow but inexorable growth of individual wealth, the rate of ownership of horses and horse-drawn carriages would inevitably result in all large cities being covered to a depth of a couple of feet in horse manure.
  7. Jul 13, 2014 #6


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    The so called Horseshit Parable. Times of London, 1894, '“In 50 years, every street in London will be buried under nine feet of manure.”
  8. Jul 13, 2014 #7
    Saved by the automobile!
  9. Jul 13, 2014 #8
    Well, unless we get nuclear fusion down right quick, which doesn't seem likely, what do you think the "alternative" is going to be this time? I'm no expert, but I don't see one. Although I'd like to see it, I don't think wind farms, solar farms, and the like are going to pick up the slack, and from a geological time-frame perspective, nature isn't isn't making any more fossil fuels.

    Looks to me like technology vs human greed is in a race against time as far as the world's energy needs...
  10. Jul 13, 2014 #9


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    That seems a strange comment to make in a history lesson.

    Some species of whale have not recovered from pre-20th-century exploitation. http://iwc.int/status

    Deforestation was an ssue in Europe, extending back to the Neolithic era.

    Admittedly the global situation with copper is not quite so clear, but for example the current UK electrical wiring system was designed to deal with copper shortages at the end of WWII.
  11. Jul 13, 2014 #10
    As an additional note, I remember hearing somewhere that the new craze of hydraulic fracking may well keep the planet rolling in fossil fuels for the next century just from USA deposits alone. Again, there's plenty of controversy over this as well, and even if it were true, what are the costs to the environment and are they worth it? http://www.businessinsider.com/fracking-shale-extraction-and-depletion-2013-3?op=1

    At some point it's going to be game over as far as fossil fuels, 50 or 100 years makes little difference if there's not a viable and sustainable replacement. Remember, too, that some estimates have the population more than doubling over the next 100 years to upwards of 14 billion: http://en.wikipedia.org/wiki/World_population

    Of course, this figure is going to be tempered directly proportional to the energy availability planetwide. I think over the next century we are going to get a first hand lesson in "Malthusianism." :http://en.wikipedia.org/wiki/Malthusianism

    Stay tuned.

    http://images.bwbx.io/cms/2013-10-10/econ_oil42__01__630x420.jpg [Broken]
    Last edited by a moderator: May 6, 2017
  12. Jul 13, 2014 #11

    jim hardy

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    We're running out of the oil that's easy to get at. Prior to WW2 California pumped enough to supply the whole country. I remember buying gasoline in the 1960's for 14.9 cents per gallon.

    Now we drill for it 6,000 feet under the ocean and way up in the tundra.
    And we get better at squeezing the last drops out of existing wells.
    That all costs.

    There's a lively debate over your question - search on "Peak Oil"

    My answer - we've run out of the cheap oil.

    To best of my memory, when i was in high school a gallon of gas cost about 1/3 as much as a gallon of milk. Now it's about the same.

    Interesting chart here

    Economics is simple - you can consume what you produce.
    Upper 95% of our economy runs on that bottom 5% which is the production of food, energy and raw materials.
    Memo to the Politicians: Tinker with energy supply at your own peril.

    I like my automobile and my water heater.
    Oil and coal industries have done a remarkable job of meeting demand. I don't regard them as "evil corporations".

    old jim
  13. Jul 13, 2014 #12


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    The numbers of whales may be down, but they're still around.

    Europe is a rather small place. There are plenty of forests in places besides Europe. This, too, is a natural resource which can be renewed.

    While the forested area of the US declined during the period when the land was settled, as timber was cleared to make farmland, the amount of area which is forested has remained largely constant over the last century or so:


    Like all natural resources, copper has suffered from periods of price instability, where the price would peak and then suffer a tremendous crash.


    As with petroleum, the amount of copper ore reserves which are economically recoverable depends on the price the finished product will fetch. Unlike petroleum, copper can be recycled, which recycling is a major source of the world copper supply, reducing the need to mine new copper ore.
  14. Jul 13, 2014 #13

    Simon Bridge

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    No worries - as you can see there are a lot of sub-issues surrounding the topic.
    When you use any resource faster than it is being made, you are going to run out ... the only question is "when".

    The videos will fill you in on some of the troubles with estimates for "when"... they all require some sort of assumptions and, it seems, everyone has some strong opinion about what sort of assumptions are valid for different purposes.
    It's a little old but the maths is correct.
    I'd just want to add the following:
    ... its ostensibly about religeon and babies, but I want to emphasize the population projection side of it to you.
    The speaker is a bit more optimistic than the unrestrained population-explosion model used in the other videos.

    Bear in mind that it is possible to argue with anything and part of the job of a scientist is to find fault with the statements of other scientists - hence the discussion above.

    The topic is also highly politicized - and easy to oversimplify.
    The main concern I have is to provide you with some tools to help you figure out what people are talking about rather than to tell you what to think. Enjoy ;)
    Last edited: Jul 13, 2014
  15. Jul 14, 2014 #14
    I find it amusing. :)

    And thank you to everyone for replying to my question. I have read some of the links and watched some the videos and it's more complicated than I thought it would be.
  16. Jul 14, 2014 #15


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    Why? The observation is that as a resource becomes scarce or expensive alternatives are often found. The fact that many forests were felled or whales were killed for oil in centuries past does not counter that observation. There are many other examples. I intended "depleted" in its "exhausted" definition, not simply "diminished".

    Apparently so for three or four species or subspecies, and other species have thrived (eastern North Pacific Grey). But the failure to recover can't have much to do with hunting for fuel oil, and the causes must lie elsewhere (pollution?, marine construction projects? subsistence hunting?)

    Exactly so, making the point about the early use of wood for fuel (and construction). Logging was also an issue in colonial America, when wide swaths of the country were denuded of trees. Pre-colonial Maine had a forest cover estimate of 92%, by 1872 it had fallen to a low of 53% forest land (Table 2), and today is back over 90%. That is, carbon for the like of blast furnaces no longer comes from trees. In general, forest cover has been increasing in the US by about 1% a year for at least the last thirty years. Europe today sees a similar increase, reversing the trend of centuries past.

    By glass fiber I'm referring to the telecommunications switch from copper to fiber optic cable in the last 20-30 years, with the rate of installation of FO now 19 million miles per year in the US alone.
  17. Jul 14, 2014 #16
    Some species of whale are extinct, others are critically endangered. This hardly proves the point that humans don't deplete your resources.

    We have been using whales as a resource, whether that is for fuel oil or for food is not really relevant. The issue is that whales are a resource and we have made many of them extinct by hunting them. Others are endangered.

    Not all species were so lucky:
  18. Jul 14, 2014 #17


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    Last edited: Jul 14, 2014
  19. Jul 14, 2014 #18


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    The point: humans tend to not exhaust global resources. Humans have a record of damaging localized ecology in the pursuit of resources (forests for instance).

    If the concern is to maintain whale populations and the like in the natural world, then of course any large scale use as a fuel is relevant.

    I think you mean endangered.

  20. Jul 14, 2014 #19
    I think I just gave two counterexamples in my previous post?

    Sure, no species has yet been made extinct. But various populations in different areas of the world has been made extinct:


    I think this should certainly count as a counterexample to your case.
  21. Jul 14, 2014 #20

    Simon Bridge

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    Guys, this is not actually that controversial:

    Humans do severely deplete and in some cases completely use up resources.
    Large scale exploitation for any use matters, the exact use is not relevant to the point.

    There exist economic pressures that can, sometimes, prevent humans from completely using up a resource ... put simply: the resource becomes so scarce (and expensive) that some other resource is more attractive.
    The impact depends on the resource and the extent of the depletion.

    It is possible for the depleted resource to recover if humans stop exploiting it in time.
    (It is even possible to have a sustainable exploitation if we are very careful.)

    The key to understanding the process though, is the exponential function.
    Most of what has been written above has been addressed in part 5 for the vid in post #2.
  22. Jul 14, 2014 #21
    Maybe algae biodiesel will pick up the slack: http://science.howstuffworks.com/environmental/green-science/algae-biodiesel.htm

    Whatever it is, it's going to have to be able to utilize the the mechanics of the billions of existing combustion engines, or you're going to have a whole "nother" nightmare to deal with. At least biodiesel circumvents this problem.
  23. Jul 15, 2014 #22

    Simon Bridge

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    When reading articles like the one quoted, it is often illuminating to check the figures.
    I'm guessing the figures being bandied about here are for the USA?

    The figure quoted is:
    ... assuming zero growth of course.

    Checking the figures:
    According to the EIA: total petroleum consumption is 6.98billion barrels of petroleum products in 2013.
    1 barrel 159 liters or 42 US gal. So that is 276.36 billion gallons just in 2013.
    Almost twice the quoted figure... unless biodiesel is twice as energy-dense as the equivalent petroleum product? Is that likely?

    Checking the zero-growth assumption: imagine my surprise when I see almost flat growth in consumption projected.
    ... looking closer - the total consumption looks to have about 1% pa growth in the projection, averaged from 2010 to 2015. Something like that. It is hard to gauge the projection but 1% kinda seems small anyway...

    Is the 95 million acres a lot of land?

    95mil acres is 148440 sq miles ... about the area of Montana.
    Montana is the 4th biggest state by area, about 4% of the total US territories.
    Sounds doable.

    Checking the maths:
    If we accept the figure: 100 acres would produce 10 million gallons - that's 10 acres/mil.gal.
    (Really need a proper citation for this figure - where did the author get it from?)

    So we take the area in acres, divide by ten, to get the number of millions of gals produced.

    i.e. 95 acres produces 9.5mil gal pa
    so 95 mil acres produces 9.5 mil-mil gal pa = 9500bil.gals pa.
    Only wanted 140bil... seems a bit puzzling to be that far out.

    Note: "experts estimate" is one of those marketing terms - goes with models in white coats holding clipboards ... clinical studies show that our product removes stains faster than a leading competitor... that should raise a red flag every time it appears in an article. Probably the discrepancy here is an artifact of a journalist using several sources and not checking the maths... but it does give reason to look sideways at the article's claims. But I am not trying to disprove what the author has said... lets keep going:

    If 95mil.acres is really what goes with the 140 bil.gal figure, then we should really need 187mil.acres to go with the actual, recent consumption figure. This is a bit bigger than Texas, or about 8% of the USA.

    Sounds promising.

    What happens if the growth is not zero? It seems reasonable to think that there should be some small increase in fuel consumption, we just want to, ideally, supply that in alternative fuels.

    Using a 1%pa growth, this means that consumption would double roughly every 70 years ... to maintain that growth, you'd need to double the land devoted to bio-diesel every generation.

    Seeing as how we are starting from scratch - that means we have to build 16%USA-area worth of algal bio-diesel plants in the next 70 years, just to catch up. (Assuming negligible algal-biodesel plants now).

    In the 70 years after that, must add another 16%, then 32% ... by the year 2224, following the plan to replace all petroleum consumption with algal-bio-diesel plants of the kind discussed in the article, the plants will occupy an area 64% of the entire territorial USA.

    Maybe some sort of state-spanning high-rise: I know, build the plants over roads!
    Roads occupy about 2% (need to check) of USA surface ... so we'd have a 32 story building on top of all the roads in 200-odd years?

    Mind you - we could slow that down a bit by using up the oil as well - the above kinda assumes a faze-out of oil use over the next 70 years. But whatever the fade-in time, 140yr, 210yr, the same figures will have to be met at the end of that.

    But none of us will be around then ;)

    I should add that all this assumes that the fuel cost of making the bio-diesel is about the same as that for extracting crude oil already. I suspect the fuel cost will be higher - but it may be less. I dont exactly have figures and algal-bio-diesel looks like it is still at the early proposition stage.

    Of course this wont happen. What will happen is that consumption will have decreased somehow.
    The trick is to choose what we want to give up before Nature chooses for us.


    Caveat: I've been a bit under the weather so I may have messed up or misunderstood something.
    Do check my arithmetic. The main point of above is to show the kind of thinking and checking needed when we read these sorts of projections.
    Last edited: Jul 15, 2014
  24. Jul 15, 2014 #23


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    For comparison, the US hovers a little under 100 million acres of corn planted, a ~third of which already goes to ethanol.

    http://www.ers.usda.gov/ImageGen.ashx?image=/media/107021/cornplantedacresandyield.jpg&width=459 [Broken]

    http://www.ers.usda.gov/ImageGen.ashx?image=/media/521847/cornuse.jpg&width=480 [Broken]
    Last edited by a moderator: May 6, 2017
  25. Jul 15, 2014 #24


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    A few other possibilities on the topic of what to do when fossil fuels become unavailable:
    • Liquid hydrocarbon fuels can also be produced synthetically, at scale, via a process like Fischer-Tropsch, given an energy source (say, nuclear fission plants, several square km of solar PV, etc), a large source of water and carbon (possibly recycled).
    • Hydrocarbon conversion technologies: like gas-to-liquids and coal-to-liquids which would switch from the smaller resource (oil) to much larger ones (gas, coal)
    • Electric transportation, again powered by nuclear fission, a lot of solar PV, etc.
    Last edited: Jul 15, 2014
  26. Jul 15, 2014 #25


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    It has. Per that EIA data, peak US petroleum consumption over the last 35 years was in Aug 2005 at 21.6 million bbls per day. As of April this year consumption was 18.7 mbpd (-13%). Total vehicle miles traveled in the US is ~flat for the last several years now, and efficiency of the vehicle fleet on the road goes up a bit every year as new replaces old. Couple other factors: the switch from oil to gas heat in New England, and the switch from petroleum based feed stocks to methane in the chemical industry given the cheap US methane prices.
    Last edited: Jul 15, 2014
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