Peak Oil and EROEI

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fifthcolumn
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Peak Oil and EROEI

Post by fifthcolumn »

From the energy bulletin peak oil primer

http://www.energybulletin.net/primer

Under the section "Why does oil peak? Why doesn't it suddenly run out?", keep reading till you hit this little nugget:

"If it takes the energy of a barrel of oil to extract a barrel of oil, then further extraction is pointless, no matter what the price of oil."

This is utter bollocks and it is EXACTLY why I get all huffy with the likes of certain people who claim that they've ALWAYS known that oil is produced using electricity.

The reason is this: if it's produced with electricity then the statement is nonsensical. If we have enough renewable energy in the form of electricity it's de facto NOT RUNNING OUT and thus it doesn't matter if it takes umpteen barrels of oil energy equivalent to get it out. What matters is if we VALUE the barrel of oil higher than we value the energy invested to get it out. We might. Or we might not.

The argument, however, is that since it's "not worth it" (and here's the stretch of the imagination coming) we therefore not only won't do it but since our entire civilisation depends on it we will collapse.

In fact, if it's electricity that we use to get it out then we depend on electricity NOT oil.

Moreover if we have any renewable sources whatsoever and find that the energy returned on investment of building these sources is positive then we end up over large timescales with a completely renewable energy infrastructure producing MORE energy than we currently have at our disposal because of compound interest.

The only way you can possibly hang on to doom is if the proportion of oil required to fuel our civilisation is so high and about to tank so suddenly and we have absolutely no spare capacity and our food production absolutely depends on oil that we have no chance of replacing it fast enough.

Are all of these assumptions true?
Personally I think probably not.
ziggy12345
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Post by ziggy12345 »

There is not a single fishing area in the whole world where the calorific value of fish caught is more than the energy expended to catch it. In malta its around 24 times the energy used than recovered. If this is true (and it is) why do we catch fish?

So I agree with you fifthcolumn. If we really want the oil and we have plenty of power from other sources then we will recover it. Sadly I cant see where all this alternative power is going to come from

Cheers
fifthcolumn
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Post by fifthcolumn »

ziggy12345 wrote: So I agree with you fifthcolumn. If we really want the oil and we have plenty of power from other sources then we will recover it. Sadly I cant see where all this alternative power is going to come from
I think it's going to take time to build.
When it is built, however, due to the greater efficiencies of electric motors I think ultimately we will have a higher standard of living with less energy usage.
Getting to there, however, I believe entails us using less while the build out takes place. To me, that's the interesting question: how fast can we build out and WILL WE?
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PS_RalphW
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Post by PS_RalphW »

ziggy12345 wrote:There is not a single fishing area in the whole world where the calorific value of fish caught is more than the energy expended to catch it. In malta its around 24 times the energy used than recovered. If this is true (and it is) why do we catch fish?

So I agree with you fifthcolumn. If we really want the oil and we have plenty of power from other sources then we will recover it. Sadly I cant see where all this alternative power is going to come from

Cheers
If fishing consumes more calories than it provides, then it is hard to see how fishing sustained entire nations before the discovery of fossil fuels. If it is true today, it simply shows how close HUMANS are to extinction, that we have fished out the oceans to the point that we can no longer catch enough fish to eat without fossil fuels.

Oil is 35% of primary energy used by man, and is by the most energy dense and versitile. There are other energy sources and other fossil fuels. Of course there is a thousand times more energy in sunlight than all the energy we use today, in reality the only thing stopping us transitioning (fairly) painlessly is the belief that the transition, if and when it comes, will be so painless that we don't need to do anything about it now or for the forseeable future.


Humanity is chosing collapse
fifthcolumn
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Post by fifthcolumn »

RalphW wrote: Oil is 35% of primary energy used by man, and is by the most energy dense and versitile. There are other energy sources and other fossil fuels. Of course there is a thousand times more energy in sunlight than all the energy we use today, in reality the only thing stopping us transitioning (fairly) painlessly is the belief that the transition, if and when it comes, will be so painless that we don't need to do anything about it now or for the forseeable future.


Humanity is chosing collapse
Humanity may be choosing collapse.

35% of our primary energy needs is oil.
If say 75% of that is transport (a likely guess given the stats from advanced countries like the US and UK) and we move to electric transport and trains (4X more efficient than oil based) then we only need to replace 0.75x35 /4 = 6.5% (+ 8.5%) = 15%.
Surely a much more reasonable (and doable) goal.

And not all regions of humanity are choosing to collapse either.
Scandinavia isn't, France isn't.
The UK might be. But we'll see.
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clv101
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Re: Peak Oil and EROEI

Post by clv101 »

fifthcolumn wrote:"If it takes the energy of a barrel of oil to extract a barrel of oil, then further extraction is pointless, no matter what the price of oil."

This is utter bollocks and it is EXACTLY why I get all huffy with the likes of certain people who claim that they've ALWAYS known that oil is produced using electricity.

The reason is this: if it's produced with electricity then the statement is nonsensical. If we have enough renewable energy in the form of electricity it's de facto NOT RUNNING OUT and thus it doesn't matter if it takes umpteen barrels of oil energy equivalent to get it out. What matters is if we VALUE the barrel of oil higher than we value the energy invested to get it out. We might. Or we might not.
Okay, I understand where your misunderstanding is coming from now.

Point 1: Civilisation needs a large amount of net energy to function, that's the energy available to do stuff other than harvest energy.

Point 2: Oil is currently our number 1 source of net energy.

We go after oil BECAUSE it is a large source of net energy. The statement above refers to the point when oil is no longer a net source of energy - at that point further extraction IS pointless IF your objective is to provide civilisation with net energy (which it is).

Whatever the source of input energy is, is irrelevant. If it takes more energy (even electrical energy from wind turbines) then we haven't got a net source of energy anymore and we might as well be attempting to run the world on Duracell batteries. They also aren't a source of net energy.

You're logic is changing the rules half way through, you're basically saying we can replace the net energy we currently get from oil with net energy from renewables. Great if we can... but for a long time now, many, many people have pointed out how the timescale and magnitude of oil decline can't be covered by renewables.
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Andy Hunt
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Post by Andy Hunt »

If we are using renewable electricity to extract oil, why not just use that renewable electricity to run cars?

EROEI still holds for peak oil. Nobody is saying that necessarily leads to TEOTWAWKI though.
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clv101
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Post by clv101 »

Andy Hunt wrote:If we are using renewable electricity to extract oil, why not just use that renewable electricity to run cars?
Same reason we manufacture Duracell batteries for the remote - some forms of energy are rather handy. AAs and diesel are pretty handy. However, oil with <1 EROEI is about as good at fueling civilisation as those double-As!
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Erik
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Re: Peak Oil and EROEI

Post by Erik »

clv101 wrote:
fifthcolumn wrote:"If it takes the energy of a barrel of oil to extract a barrel of oil, then further extraction is pointless, no matter what the price of oil."

This is utter bollocks and it is EXACTLY why I get all huffy with the likes of certain people who claim that they've ALWAYS known that oil is produced using electricity.

The reason is this: if it's produced with electricity then the statement is nonsensical. If we have enough renewable energy in the form of electricity it's de facto NOT RUNNING OUT and thus it doesn't matter if it takes umpteen barrels of oil energy equivalent to get it out. What matters is if we VALUE the barrel of oil higher than we value the energy invested to get it out. We might. Or we might not.
Okay, I understand where your misunderstanding is coming from now.

Point 1: Civilisation needs a large amount of net energy to function, that's the energy available to do stuff other than harvest energy.

Point 2: Oil is currently our number 1 source of net energy.

We go after oil BECAUSE it is a large source of net energy. The statement above refers to the point when oil is no longer a net source of energy - at that point further extraction IS pointless IF your objective is to provide civilisation with net energy (which it is).

Whatever the source of input energy is, is irrelevant. If it takes more energy (even electrical energy from wind turbines) then we haven't got a net source of energy anymore and we might as well be attempting to run the world on Duracell batteries. They also aren't a source of net energy.

You're logic is changing the rules half way through, you're basically saying we can replace the net energy we currently get from oil with net energy from renewables. Great if we can... but for a long time now, many, many people have pointed out how the timescale and magnitude of oil decline can't be covered by renewables.
This post adds a lot of clarity to a somewhat murky subject Chris, thanks. And I think Andy's point is relevant too.

If it is economically viable to, say, use wind energy in order to produce 10 electrical energy units which are needed to extract and refine 1 barrel of oil which itself contains only 5 energy units, then it will probably also be economically viable to simply use that electrical energy directly in a battery powered vehicle. Because oil is so useful and practical as an easily transportable energy store, I can imagine it being produced and used when the EROEI is below 1. But surely at some stage of EROEI<<1 the economics will cease to make sense as electricity producers find more profitable ways to market this electrical energy instead of using it to extract and refine oil.
"If we don't change our direction, we are likely to wind up where we are headed" (Chinese Proverb)
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DominicJ
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Post by DominicJ »

Peak Oil is not Peak Energy.
It may be, but if thats the case, lets discuss peak energy instead.
"If it takes the energy of a barrel of oil to extract a barrel of oil, then further extraction is pointless, no matter what the price of oil."
That statement is bollocks, and its easy to see why RGR gets so annoyed when people defend it.

How about this, if you have 10kj of crude oil, and can turn it into 9kj of petrol, would you?
You have a negative EROEI, so you wouldnt?
But then, my car doesnt run on crude...
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clv101
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Post by clv101 »

It's not bollocks. It all comes down to whether you want net energy from oil. In your petrol example, if it took 10kj to produce 9kj - you wouldn't be running civilisation on it.

No one is arguing that there isn't lots and lots and lots of EROEI < 1 energy out there. There's no limit to how much EROEI < 1 liquid fuel we can produce. That isn't our problem though. We need EROEI > 1, net sources of energy.
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DominicJ
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Post by DominicJ »

No one is arguing that there isn't lots and lots and lots of EROEI < 1 energy out there
"If it takes the energy of a barrel of oil to extract a barrel of oil, then further extraction is pointless, no matter what the price of oil."
He is
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PS_RalphW
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Post by PS_RalphW »

Good post on The Oil Drum about future coal supplies.

http://www.theoildrum.com/node/5256

This predicts peak coal some time in the next 40 years, with a net energy best guess of 2026 - 18 years from now.

I think we can assume that peak coal and peak oil (and probably peak gas) will be be peak energy, unless we invest heavily in renewables very fast.

More importantly, we need to adapt society to a much lower energy density.
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clv101
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Post by clv101 »

DominicJ wrote:
No one is arguing that there isn't lots and lots and lots of EROEI < 1 energy out there
"If it takes the energy of a barrel of oil to extract a barrel of oil, then further extraction is pointless, no matter what the price of oil."
He is
No, he's not. He's saying it's "pointless". The point he's talking about is it providing net energy.
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DominicJ
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Post by DominicJ »

But "net energy" is not the only reason we use oil, and we will still use it, even if it isnt net energy anymore, just like we still use disposable batteries.

Either he's ill informed, he's using very sloppy language, or he's deliberatly attempting to deceive.
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