EROEI of Medieval Society

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sofistek's picture
sofistek
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EROEI of Medieval Society

In chapter 17b of the crash course, Chris states:

If, instead, these people were able to produce just 1.2 calories for every 1 calorie expended, then they’d have the exact energy balance that existed in medieval times. This skinny 20% surplus allotment of energy is sufficient to allow rich hierarchies to form, job specializations to develop, and large works of architecture to be built.

This implies an EROEI of 1.2:1, for medieval societies.

Another fellow of the Post Carbon Institute, Richard Heinberg, in his recent essay, Searching for a Miracle", states that the hunter-gatherer society is perhaps the simplest model for a society and operated on an EROEI of 10:1. He suggests, therefore, that an EROEI of 10:1 may be the minimum that is needed for a society. It would seem that complex societies require an EROEI of greater than 10:1.

So how can both Richard's and Chris's comments be reconciled? Perhaps they aren't both using the same measurement.

For me, it seems unlikely that any society could exist on an EROEI of 1.2:1, and I wonder if Chris inadvertently put that decimal point in, although the 20% figure seems to confirm it. I assume the energy sources in medieval times would have been food, wood, wind and hydro, of sorts. If the people producing and distributing that energy consumed 83% of it in just proding it, then only 17% of the energy produced, has to support the rest of society, including all those not involved in energy production and all of the lifestyles of those involved in energy production, when they are not producing energy.

I'd be grateful for any thoughts on this and, if Chris could expand on his statement, with references, that would be even better.

[I've also posted this on the crash course forum though that is not nearly as active as this one, so I thought I'd try here too - I hope that's OK]

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deggleton
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Re: EROEI of Medieval Society
sofistek wrote:

In chapter 17b of the crash course, Chris states:

If, instead, these people were able to produce just 1.2 calories for every 1 calorie expended, then they’d have the exact energy balance that existed in medieval times. This skinny 20% surplus allotment of energy is sufficient to allow rich hierarchies to form, job specializations to develop, and large works of architecture to be built.

This implies an EROEI of 1.2:1, for medieval societies.

Another fellow of the Post Carbon Institute, Richard Heinberg, in his recent essay, Searching for a Miracle", states that the hunter-gatherer society is perhaps the simplest model for a society and operated on an EROEI of 10:1. He suggests, therefore, that an EROEI of 10:1 may be the minimum that is needed for a society. It would seem that complex societies require an EROEI of greater than 10:1.

So how can both Richard's and Chris's comments be reconciled? Perhaps they aren't both using the same measurement.

For me, it seems unlikely that any society could exist on an EROEI of 1.2:1

It certainly would be interesting to have a look at the sources on which each of them relied.  I suspect your imagination, however, is the more important factor here.  That's not a put-down; all of us have lived our entire lives in this populous and highly energized anomaly, and what we can conceive is affected by it.  Simple and complex are vague terms arbitrarily applied, and economy, not society, might better serve your thinking and imagining about EROEI.

There's so much about ways of other times and places we don't have in proper perspective and relationship.  It's as if we're doing a puzzle without any edge pieces on the table.

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Re: EROEI of Medieval Society

It seems to me, though, that it's an important issue. If the level of complexity (though, admittedly, a standard measure of that would be difficulty) is determined by EROEI or, perhaps, by the net energy available, then EROEI will determine how complex a sustainable society can be. If a miracle ever occurs and people finally realise that unsustainable societies cease to exist, then designs for a sustainable society may be more or less limited by the net energy available.

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Re: EROEI of Medieval Society

Now I remember that I winced and groaned during this chapter (17b) because CM tried to make a principle of a limited historical fact.

Chris wrote:

"Key Concept #14: Social complexity is built upon surplus energy. If we want to maintain our society in its current form, we are going to have to master this concept, and fast."

Beyond the observation, I don't think he's entirely correct.  The whole person paradigm reveals that social complexity is a given.  If there are people, there is social complexity to discover, honor, use and celebrate.  Obtaining and sustaining the benefits is a matter of interest, courage and care.

We've struggled with that.  So many of our energy requirements are consequences of learned and reinforced discounting and denial of whole people.

We cannot get at what's given, or approach sustainability, if we maintain our society in its current form.  At least that's what history shows me.

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Re: EROEI of Medieval Society

I cannot provide references, but my understanding of the relationship between social complexity and energy needs is more nuanced. Others I have read (including Richard Heinberg) have explained it better than I can, but I see the relationship between social complexity and EROEI as something like a parabolic curve.  With early investments in social complexity, the EROEI improves rather dramatically; as complexity continues to rise, the EROEI eventually reaches a plateau; and, with even further complexity, EROEI begins to decline.

If you think of simple examples, the principle is fairly obvious. With a single individual, as a hunter-gather, for example, most of his/her activities must be directed toward his/her mere survival, with perhaps some surplus that can be stored for the future. With a small group of individuals, there can be some specialization of roles, ideally based upon particular talents, resulting in greater resource utilization, improved sharing of those resources and derived goods, and increased surpluses. With further social complexity, there comes a point where those benefits in resource utilization begin to decline, and the further development of social complexity is hindered.

Enter fossil fuels, which provide the equivalent of a turbocharger to your automobile, and much greater social complexity is possible. In essence, with the introduction of fossil fuels, a new parabolic curve has been created. The new curve will again have a plateau, beyond which further increases in social complexity will result in comparably lower EROEI, but the new plateau will be much higher than that which existed prior to fossil fuels.

With the upcoming peak in fossil fuel extraction, we will find that our currently (very) complex social structure will likely be unsustainable, and our social structures will be forced to simplify.

So, I do not necessarily see a disconnect between the ideas set forth by Chris Martenson and those of Richard Heinberg, although I cannot make a judgement regarding which EROEI is "correct" for a given situation. It is clear that our currently complex societies will become less and less sustainable with time, but I do not think that the majority of humankind will regress to small group hunter-gatherers.

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Re: EROEI of Medieval Society

 

 I'd have thought that for any society, in the long run population reaches an equilibrium with the energy source..

calorific surplus gets converted into either more people... or perhaps capital projects like pyramids, cathedrals...

 A lone hunter gatherer may well have a huge surplus, he has first choice and will choose the easiest, most calorie laden food..

 once a few generations have gone by, his great great great grandchildren find themselves competing with each other to scrape by.. consuming ever more marginal materials.. like grasses, bark, insects.. (the "tar sands" equivalent of foraging..)

 In the last few centuries the population has exploded thanks to the fossil energy windfall.

...as that windfall goes away faster than population can adjust..  we have a real problem.

 

 

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Re: EROEI of Medieval Society

I doubt we'll see an inside-the-box explication better than Christopher's.  Bravo!

There are diminishing returns from what inside-the-box thinking calls social complexity.  Observers including Buckminster Fuller concluded that specialization and irresponsibility go hand-in-hand.

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Re: EROEI of Medieval Society
ccpetersmd wrote:

I cannot provide references, but my understanding of the relationship between social complexity and energy needs is more nuanced. Others I have read (including Richard Heinberg) have explained it better than I can, but I see the relationship between social complexity and EROEI as something like a parabolic curve.  With early investments in social complexity, the EROEI improves rather dramatically; as complexity continues to rise, the EROEI eventually reaches a plateau; and, with even further complexity, EROEI begins to decline.

I would have thought that EROEI would begin to decline, regardless of complexity, because of geological and resource constraints. I'm not sure how complexity can continue to increase if EROEI declines. However, I can see that it may not be a precise correlation between EROEI and complexity (however that is measured).

ccpetersmd wrote:

With a single individual, as a hunter-gather, for example, most of his/her activities must be directed toward his/her mere survival, with perhaps some surplus that can be stored for the future.

Current understanding seems to be quite different. Hunter-gatherers generally spent very little energy (which is mainly human, so this equates to very little time) with survival issues. They had a lot of leisure time, and maybe this is part of the problem. Though their society was/is very simple (and happy, apparently) abundant food supplies (usually) allowed a lot of leisure time. Perhaps if we substitute complexity for leisure, more complex societies can be supported with similar, or possibly lower, EROEI.

However, the 1.2 figure for medieval societies seems way too low to me, no matter how one looks at complexity of such societies.

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Re: EROEI of Medieval Society

I found the following resources of interest and relevant to this post:

http://web.mac.com/biophysicalecon/iWeb/Site/BPE%20Conference_files/Down...

http://europe.theoildrum.com/pdf/theoildrum_4428.pdf

As to the leisure time available to a solo hunter-gatherer, it would depend in large part upon the richness of the resources available, the habitability of the land, and the skill of the individual. One could imagine that an individual on a tropical island, with abundant natural resources (fish from the sea, bananas, etc.), might have a much easier time of it than the same individual in Alaska, where resources may be abundant, but the environment more challenging. If the resources on the tropical island were more depleted (because of overpopulation, for example), more time would need to be dedicated to securing the necessary resources, and the individual in Alaska may be relatively better off.

Social complexity tends to develop naturally. If resources are abundant (fossil fuels, new lands, etc.), a more complex society is possible, and that complexity will be vulnerable to changes in resource availability. But, even without fossil fuels, humans have tended to form more complex societies than tribes of hunter-gatherers, and language was an important key to this development, of course. I have no doubt that with the passing of the fossil fuel age, our societies will become much less complex than many are currently, but I do not foresee most humans returning to a hunter-gatherer lifestyle. We will still tend to specialize somewhat, depending upon resource availability and particular talents and interests. At least, as a physician, I hope my skills will still be valuable, if only in trade for some venison or a bushel of tomatoes!

Its a brave, new world...

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Re: EROEI of Medieval Society
sofistek wrote:

designs for a sustainable society may be more or less limited by the net energy available.

It's comforting that the energy-marshalling fathers who know best are likely to face constraints.  Then the children will be able to self-organize as never before.

You needn't worry about social complexity, guys.

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sofistek
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Re: EROEI of Medieval Society

Some interesting posts, though I'm no further forward in discovering how Chris can quote an EROEI of 1.2:1 for medieval society, whilst Richard Heinberg argues that 10:1 is probably the lowest EROEI required for any society. One of the links that ccpetersmd gave does suggest a lower EROEI, of 5:1 for complex societies, though no detail is given on just how complex that society would be. Even so, it is still some way off Chris's figure and I'd love to know where he got that figure and what it really represents, since it seems unlikely that any society that does anything significant beyond gathering energy would be unable to exist at an EROEI as low as 1.2:1. At least Heinberg gives some references for the 10:1 hunter-gatherer society EROEI.

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Re: EROEI of Medieval Society

Your question keeps echoing as I go through my days.  I hope CM notices it and sheds light on the seeming discrepancy, because the chances of a third party divining the explanation are very small.  Have you written to him and to RH?

That said, I've also begun to think CM's point about surplus going to growth or prosperity, because they're not really the same, is cogent here.  What you and CM call social complexity (correlated with growth) is not the only possible outcome of energy use.  One way or another, societies choose outcomes and manifest different EROEIs.

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sofistek
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Re: EROEI of Medieval Society
deggleton wrote:

Your question keeps echoing as I go through my days.  I hope CM notices it and sheds light on the seeming discrepancy, because the chances of a third party divining the explanation are very small.  Have you written to him and to RH?

Yeah; that was the first thing I did but only got standard replies back. Hence this discussion topic.

deggleton wrote:

That said, I've also begun to think CM's point about surplus going to growth or prosperity, because they're not really the same, is cogent here.  What you and CM call social complexity (correlated with growth) is not the only possible outcome of energy use.  One way or another, societies choose outcomes and manifest different EROEIs.

I'm not sure about growth because growth could be possible just by adding people (and hence more people to obtain energy, supported by an EROEI above 1:1) but, certainly, prosperity (as measured by standard of living, perhaps) would require excess energy. In fact, anything that is not directly contributing to obtaining energy requires excess energy, over and above the energy required to obtain it.

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