Declining net energy

Summary – Add post summary.

The challenge of declining net energy

EROEI and ECoE

ENERGY TAX

Is energy cost of energy a carbon tax. Certainly energy cost of energy going up doesn’t change the amount of carbon that is emitted in the gross use. But it does make the use of that energy more expensive to the average homeowner possibly having them change their behavior that is instead of taking that long cruise you decide to do a backyard staycation. As people’s income drops particularly their discretionary income this will be even more pointed that is they have less and less getting accomplished for the same amount of spending and so an energy cost of energy rise they cause people into the binary choice of that cruise or that vacation the backyard vacation. Another way of thinking about this is that we know that only during recessions have we seen dramatic drops in emissions from countries. What energy cost of energy does is create the equivalent eventually of a recession and therefore reduces emissions. Paragraph paragraph

So in effect energy cost of energy has a possible outcome at the extreme of a carbon tax or carbon pricing. In this way we should look at energy cost of energy as a good thing and this notion of Ero e i or energy cost of energy as the way in which we see a connection between the effect of energy to send and the needs of climate change.

Some Recent Research

Salehiab, M., H. Khajehpoura & Y. Saboohia (2019) Extended Energy Return on Investment of Multiproduct Energy Systems. Energy, 116700)
DOI: 10.1016/j.energy.2019.116700
Source: www.sciencedirect.com/science/article/pii/S0360544219323953

Highlights (from ScienceDirect website)
– The EROI of a multi-product oil and gas production unit in Iran is assessed.
– LCA is used to obtain environmental externalities as an embodied energy investment.
– Consideration of LCA emissions & indirect energy investments reduces EROI by 75%.
– The exergy cost-based allocation of the invested energy is investigated.
– Improper allocation of invested energy results in an error of aggregation of 11.3%.

Abstract – Energy Return on Investment (EROI) is an indicator of how efficient is an energy supply system. In the present study, the conventional approach of EROI assessment is extended to include the equivalent energy investment needed for offsetting the life cycle environmental impacts. Moreover, the issue of allocation of the invested energy among different by-products is addressed. The EROI of multiple products has been specified using different benchmarks of price, energy content, exergy content, and exergy costs. The application of the concept is demonstrated through a case study of an Iranian oil production unit. The overall conventional and environmentally-extended EROI values of the produced oil in Iran is estimated to be 26.8:1, 23.3:1, respectively. Also, when taking the downstream environmental emissions into account, the EROI will be as low as 6.8:1. This shows that the EROI may be overestimated by 75% if the embodied costs are not taken into account. The comparison of the aggregated EROI estimates based on state-properties (price, energy, and exergy) and disaggregated process-property (exergy cost), gives a measure of the error of aggregation. It is shown that this error may be as high as 11.5% in the case of the multi-product energy system of the studied case.

Rigo E. Melgar-Melgar & C.A.S. Hall (2020) Why ecological economics needs to return to its roots: The biophysical foundation of socio-economic systems. Ecological Economics, 169, 106567.
DOI: 10.1016/j.ecolecon.2019.106567
Source: www.sciencedirect.com/science/article/abs/pii/S0921800919310304

Excerpt – Studies of EROI, have been very much a part of the renaissance of biophysical economics, especially in Europe and China where depletion of oil and gas are much more pertinent issues than in the United States (for now). In 2011, a special issue of 21 articles in the Journal Sustainability on “New Studies in EROI,” furthered cemented the importance of biophysical analyses to understand the nexus between energy and economic process (Hall and Hansen, 2011). Younger researchers entering the field have developed new measurements of EROI. For example, Court and Fizaine (2017) have derived the energy cost of generating all of the energy a society uses from its monetary costs, for which there are good records going back centuries. Celi et al. (2018) derived estimates from CO2 released (which were required for environmental accounting) and concluded that these were not too different from the values reported in the literature. A formal comparison of EROI values derived from these very different approaches would seem to be a useful endeavor. Many analysts believe EROI is a critical tool for understanding the future of civilization.

The frontier of BPE today includes a wide range of other topics as well. For example, Hall and Ramírez-Pascualli (2013) explore how vital fossil fuels are for the development of modern socio-economic systems. Feng et al. (2013) provide one of the first biophysical analyses of fossil fuels in China, and forecast future trends in energy supply and demand for the world’s second largest economy. In Spain’s Photovoltaic Revolution: The Energy Return on Investment (2013), the authors of this paper worked with Pedro Prieto to perform one of the first large-scale biophysical analysis of solar energy to comprehensively assess the EROI of solar power when all costs are computed, and to understand the implications of subsides via feed-in-tariff polices for the overall economic crisis of Spain. In America’s Most Sustainable Cities and Regions: Surviving the 21st Century Megatrends, Day and Hall (2016) provide a comprehensive biophysical analysis of how the urban and rural regions of the United States will cope with the threat of climate change depending on the situation regarding access to energy, and the probability of environmental impacts. In Energy, Complexity and Wealth Maximization, Ayres (2016) gives a comprehensive survey of energy in wealth creation, and emphasizes how all evolutionary processes have always depended on physical laws. Palmer and Floyd (2017) undertake a comprehensive analysis of EROI of photovoltaic systems and their increased needs for backup as they become a larger share of our economy. Dittmar (2017) undertakes a comprehensive analysis of oil futures by region and provides a much less rosy perspective than official sources such as EIA. Tverberg (2019) sees peak oil use coming not only from geological limitations but also from the resulting price increases and the impacts on the poor. Herendeen (2019) calls for analyzing the spatial impacts of “renewability” and the biophysical implications of net zero energy plans in cities such as Burlington, Vermont which have already achieved 100% renewable electricity coverage. Hall and Balogh (2019) consider the biophysical requirements of our urban centers in their comprehensive textbook on Urban Ecology.

i’m not sure who your reading. But the sources that I’m finding are not gloom and doom folks. And they are not sloppy thinkers. I’m trying to share credible reports, peer-reviewed if possible, and provide links to sources. Consider the CSS, USDA, PCI, and others.

https://css.umich.edu/publications/factsheets/food/us-food-system-factsheet … -factsheet

Image

https://www.postcarbon.org/publications … y-descent/

https://www.academia.edu/5548375/Canning_et_al_2010

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A review of EROEI-dynamics energy-transition models.
by Craig D. Rye & Tim Jackson
Energy Policy (2018) 122: 260-272.

DOI: https://doi.org/10.1016/j.enpol.2018.06.041
… via%3Dihub
… QsGorpZE3p

Highlights (from ScienceDirect website)
• Energy-economy interactions can be insightfully simulated in terms of EROEI.
• The EROEI modelling literature highlights a common set of dynamics for energy transitions.
• Principally, energy constraints could drive a reduction in 21st century material prosperity.
• The development of EROEI modelling literature can be studied and divided into sub groups.
• A number of key areas for additional work are identified and discussed.

Abstract (from article) [emphasis added]
The need for an environmentally sustainable economy is indisputable but our understanding of the energy-economy interactions (dynamics) that will occur during the transition is insufficient. This raises fascinating questions on the future of economic growth, energy technology mix and energy availability. The crucial interactions between energy and economy systems can be usefully described in terms of the Energy Returned on Energy Invested (EROEI) metric (the energy cost of primary energy production). Multiple authors have used this metric to explore the behaviour of the economy over the transition to lower carbon energy sources. The following text is a review of energy-economy models that incorporate the EROEI metric. In particular, the EROEI dynamics literature is found to describe a common set of dynamics associated with the transition to lower EROEI primary energy resources. These include: the rising resource-cost of primary energy production, the short-term misallocation of resources, the short-term overproduction of energy and the potential decline in economic stability. The literature can be divided into groups of related models. Following the review, a number of key areas for additional work are identified and discussed.

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Energy expenditure, economic growth, and the minimum EROI of society.
by Florian Fizaine & Victor Court
Energy Policy (2016), 95: 172-186

DOI: https://doi.org/10.1016/j.enpol.2016.04.039
https://drive.google.com/open?id=1VbyLy … d14X0hl1HL

Abstract: [emphasis added]
We estimate energy expenditure for the US and world economies from 1850 to 2012. Periods of high energy expenditure relative to GDP (from 1850 to 1945), or spikes (1973–74 and 1978–79) are associated with low economic growth rates, and periods of low or falling energy expenditure are associated with high and rising economic growth rates (e.g. 1945–1973). Over the period 1960–2010 for which we have continuous year-to-year data for control variables (capital formation, population, and unemployment rate) we estimate that, statistically, in order to enjoy positive growth, the US economy cannot afford to spend more than 11% of its GDP on energy. Given the current energy intensity of the US economy, this translates in a minimum societal EROEI of approximately 11:1 (or a maximum tolerable average price of energy of twice the current level). Granger tests consistently reveal a one way causality running from the level of energy expenditure (as a fraction of GDP) to economic growth in the US between 1960 and 2010. A coherent economic policy should be founded on improving net energy efficiency. This would yield a “double dividend”: increased societal EROEI (through decreased energy intensity of capital investment), and decreased sensitivity to energy price volatility.

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Dynamic Energy Return on Energy Investment (EROI) and material requirements in scenarios of global transition to renewable energies.
by Iñigo Capellán-Péreza, Carlos de Castroa & Luis Javier Miguel Gonzáleza
Energy Strategy Reviews (2019) 26: 100399
DOI: https://doi.org/10.1016/j.esr.2019.100399
https://drive.google.com/open?id=1TCd_e … ZoQbcEjq3S

Highlights [from ScienceDirect]:
• Methodology to assess the energy and material investments associated to renewables.
• Their assessment is critical for the correct planning of renewables’ deployment.
• EROI in fast transition scenarios incompatible with high levels of development.
• The transition to renewables may drive a re-materialization of the economy.
• These results put into question the consistence of the Green Growth narrative.

Abstract [from article, emphasis added]:
A novel methodology is developed to dynamically assess the energy and material investments required over time to achieve the transition from fossil fuels to renewable energy sources in the electricity sector. The obtained results indicate that a fast transition achieving a 100% renewable electric system globally by 2060 consistent with the Green Growth narrative could decrease the EROI of the energy system from current ~12:1 to ~3:1 by the mid-century, stabilizing thereafter at ~5:1. These EROI levels are well below the thresholds identified in the literature required to sustain industrial complex societies. Moreover, this transition could drive a substantial rematerialization of the economy, exacerbating risk availability in the future for some minerals. Hence, the results obtained put into question the consistence and viability of the Green Growth narrative.

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Long-Term Estimates of the Energy-Return-on-Investment (EROI) of Coal, Oil, and Gas Global Productions.
by Victor Court & Florian Fizaine
Ecological Economics (2017) 138: 145–159.
DOI: https://doi.org/10.1016/j.ecolecon.2017.03.015
https://drive.google.com/open?id=1C17n9 … iHZ3fmHqAe

Highlights [from ScienceDirect]
• Through a price-based approach we assess the global energy-return-on-investment (EROI) of coal, oil, and gas.
• This is done from their respective beginning of reported production (respectively 1800, 1860, and 1890) to 2012.
• We also present a new theoretical EROI dynamic model based on Dale et al. (2011).
• We find that maximum EROI of global oil and gas productions have both already been reached in the 1930s–40s, respectively around 50(± 15):1 and 150(± 20):1.
• We estimate that the maximum EROI of global coal production will most likely be around 95(± 15):1 around the 2030s.

Abstract [from article]
We use a price-based methodology to assess the global energy-return-on-investment (EROI) of coal, oil, and gas, from the beginning of their reported production (respectively 1800, 1860, and 1890) to 2012. It appears that the EROI of global oil and gas productions reached their maximum values in the 1930s–40s, respectively around 50:1 and 150:1, and have declined subsequently. Furthermore, we suggest that the EROI of global coal production has not yet reached its maximum value. Based on the original work of Dale et al. (2011), we then present a new theoretical dynamic expression of the EROI. Modifications of the original model were needed in order to perform calibrations on each of our price-based historical estimates of coal, oil, and gas global EROI. Theoretical models replicate the fact that maximum EROIs of global oil and gas productions have both already been reached while this is not the case for coal. In a prospective exercise, the models show the pace of the expected EROIs decrease for oil and gas in the coming century. Regarding coal, models are helpful to estimate the value and date of the EROI peak, which will most likely occur between 2025 and 2045, around a value of 95(± 15):1.

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A New Approach to Calculating the “Corporate” EROI.
by Celi, Volpe, Pardi & Siboni
BioPhysical Economics and Resource Quality (2018) 3:15
DOI: https://doi.org/10.1007/s41247-018-0048-1
https://drive.google.com/open?id=1ZL5tj … f3wQZwc60-

Abstract [from article]:
The EROI is one of the most important indices to evaluate the net energy output of a source of primary energy (there is a lively debate on the usability of this kind of parameter, but here we will use it under the hypothesis that it is a good way to establish if an oil company has a level of efficiency close to other energetic sources). It is generally defined as the ratio between the energy extracted by a given resource and the energy costs sustained to extract that energy. We tried to set up an alternative method for the calculation of the EROI, taking (1) as a proxy of the energy costs the available data about the CO2 emissions of the oil companies, as reported in the sustainability reports (SRs), recommended by the international organisms such as IPCC and WBCSD, although not mandatory, and (2) as a proxy of the energy extracted the CO2 emissions estimate obtained by a stoichiometric conversion of the oil/gas production declared by the oil companies. Both proxies have been also corrected to take into account the different CO2 emission rate per unit energy of oil and gas. The resulting estimates of EROI are rather homogeneous and not too different from the values reported in the literature. The method could be suitable for year-by-year comparison of the time evolution of this important energy quality parameter for the individual energy producing and energy-delivering companies.

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EROI and the Icelandic society.
by Reynir Smari Atlason
Energy Policy (2018) 120: 52–57.
DOI: https://doi.org/10.1016/j.enpol.2018.04.069
https://drive.google.com/open?id=1tR1O8 … bgQnzK71O4

Highlights (from ScienceDirect website)
• Since the two oil crisis in 1970’s, Icelanders have mostly relied on energy provision from renewable sources.
• The Icelandic society has maintained societal EROI over 40:1 for the most part since 1975.
• Icelanders have mostly avoided fluctuations in societal EROI because of less reliance on imported fossil fuels.
• High societal EROI may influence the general prosperity on the island, despite its isolation.

Abstract (from article)
In this paper, the societal Energy Return on Investment (EROIsoc) is estimated for Iceland between 1960 and the present. The results indicate that the overall EROIsoc was around 27:1 in the early 1960s, and was volatile for a period of time before stabilizing at around 45:1 in 1974 after establishing a strong mix of renewable energy. These findings further show that Icelanders have generally had access to energy sources with higher EROI than if they had relied on fossil fuels, except for the period between 1963 and 1967. If they had relied on fossil fuels alone, Icelanders would now have access to combined resources with an EROI of around 16:1, likely too low for prosperity, and an even lower EROI for long periods of time. Regarding policies, this paper shows that relying on an energy grid mix with an EROI higher than 20-30:1, especially for island nations, has the potential to raise the standard of living greatly. For policymakers in island nations, attention should be given to this relationship between high-EROI energy sources with low price volatility and the standard of living.

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Estimation of global final-stage energy-return on investment for fossil fuels with comparison to renewable energy sources.
by Brockway, Owen, Brand-Correa & Hardt
Nature Energy (2019) 4: 612–621
DOI: https://doi.org/10.1038/s41560-019-0425-z
… 8m1ejSUT2_

Abstract (from article)
Under many scenarios, fossil fuels are projected to remain the dominant energy source until at least 2050. However, harder-to-reach fossil fuels require more energy to extract and, hence, are coming at an increasing ‘energy cost’. Associated declines in fossil fuel energy-return-on-investment ratios at first appear of little concern, given that published estimates for oil, coal and gas are typically above 25:1. However, such ratios are measured at the primary energy stage and should instead be estimated at the final stage where energy enters the economy (for example, electricity and petrol). Here, we calculate global time series (1995–2011) energy-return-on-investment ratios for fossil fuels at both primary and final energy stages. We concur with common primary-stage estimates (~30:1), but find very low ratios at the final stage: around 6:1 and declining. This implies that fossil fuel energy-return-on-investment ratios may be much closer to those of renewables than previously expected and that they could decline precipitously in the near future.

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marmico wrote:
Brockway’s conclusion is that fossil fuel final energy stage EROI has declined from 6.8:1 in 1995 to 6.1:1 in 2011. … The difference between 85.3% net energy in 1995 and 83.6% in 2011 rounded is a 1 percentage point … within reasonable rounding error of any EROI study.

True. But isn’t it also correct to say that the decline from 6.8 to 6.1 is 10.3%.

A ten percent decline over every ~15 years might be something techno-industrial society can adapt to, provided the decline rate doesn’t turn out to be non-linear (or, the effect(s) upon society are non-linear). This non-linear change notion is something that Morgan points out in his discussion of the societal impacts of an increasing ECoE.

Also, the declining final stage level reported in their analysis is worrisome should it turn out that techno-industrial society actually needs EROEI at or above that 6.1 level. “It is assumed that ERoEI >5 to 7 is required for modern society to function.” Euan Mearns (2016). At: http://euanmearns.com/eroei-for-beginners

Others suggest that an EROEI below 11 is where noticeable effects occur:

Murphy (2013) [ … 6/20130126 ] found that society needed at least an EROI of 11. So much net energy is provided by any energy resource with an EROI of 11 or higher, that the difference between an EROI of 11 and 100 makes little difference. But once you go below 11, there is such a large, exponential difference in the net energy provided to society by an EROI of 10 versus 5, that the net energy available to civilization appears to fall off a cliff when EROI dips below 10 (Mearns 2008). Source: http://energyskeptic.com/2016/lambert-h … y-of-life/

Hall et al. come up with very similar values:

(1) Hall, Balogh & Murphy (2009). What is the minimum EROEI that a sustainable society must have? Energies, 2, 25-47.
(2) Hall (2012). Energy return on investment. In Butler et al. [Eds.] The Energy Reader. (pp. 62-68) Sausalito, CA Watershed Media.

Stepping back for a moment, EROEI values between 5 and 11, and declining, seem to be of some consequence.

But perhaps focusing on just a single EROEI number might hide some of the societal risks involved. Work has begun to explore what end-use EROEI values are needed for various elements of techno-industrial civilization. Certainly need more research here, but the initial findings do catch one’s attention. (I wonder where websites like this one, the servers we use, the larger network, our time, etc. fall in this triangle?)
Image Image from: http://energyskeptic.com/2016/lambert-h … eroi-12-14 Published source of image: Lambert, J.G., Hall, C.A.S., et al. (2014) Energy, EROI and quality of life. Energy Policy. 64:153–167. https://mahb.stanford.edu/wp-content/up … l_2013.pdf

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Annual changes in energy quality and quality of life: A cross-national study of 29 OECD and 37 non-OECD countries.
by Bowen Liu & Jun Matsushima
Energy Reports (2019) 5: 1354-1364
DOI: https://doi.org/10.1016/j.egyr.2019.09.040
https://drive.google.com/open?id=18yoVp … rJN7KiopJ-

Highlights (from ScienceDirect):
• Annual changes in the relation between EROIsoc, GDP, EC, and QoL are investigated.
• The relation between EROIsoc, GDP, EC, and QoL differs between OECD and non-OECD.
• The importance of EROIsoc for OECD increases in times of increasing energy prices.
• The importance of GDP for non-OECD decreases in times of increasing energy prices.

Abstract (from article):
Since the efficiency of obtaining energy is decreasing, it is important to determine how the degradation
in energy quality will influence society. Despite the rising importance of net energy, few quantitative
studies have been conducted on the relationship between energy quality and quality of life (QoL).
Energy return on investment on a society scale at a national level (EROIsoc) is used as an indicator of
energy quality, energy consumption (EC) per capita is used to represent energy quantity, and gross
domestic product (GDP) per capita is used as an economic factor. Eight indices are used for QoL.
Simple linear regression analysis is used to discuss the correlation coefficients between the three
indicators (EROIsoc, GDP per capita, and EC per capita) and eight QoL indices for 29 OECD and 37
non-OECD countries, and their annual changes over the 25 years from 1990 to 2015. We demonstrate
that the relationship between the three indicators and eight QoL indices changes annually and differs
between OECD and non-OECD countries. We also demonstrate that although GDP per capita is the most
influential factor among the three indicators for the Human Development Index (HDI), which is one
of the best-known composite indices of well-being, the importance of GDP per capita for non-OECD
countries has declined, especially in times of increasing energy prices, while the importance of EROIsoc
for OECD countries has increased.

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Re: New EROEI research

Postby aspera » Fri 10 Jan 2020, 23:12:15
Developing an Input-Output Based Method to Estimate a National-Level Energy Return on Investment (EROI).
by Lina I. Brand-Correa, et al.
Energies (2017) 10(4), 534.
DOI: https://doi.org/10.3390/en10040534
https://drive.google.com/open?id=155St3 … lUQOPn0KqJ

Abstract (from article, emphasis added):
Concerns have been raised that declining energy return on energy investment (EROI) from
fossil fuels, and low levels of EROI for alternative energy sources, could constrain the ability of
national economies to continue to deliver economic growth and improvements in social wellbeing
while undertaking a low-carbon transition. However, in order to test these concerns on a national
scale, there is a conceptual and methodological gap in relation to calculating a national-level EROI
and analysing its policy implications. We address this by developing a novel application of an
Input-Output methodology to calculate a national-level indirect energy investment, one of the
components needed for calculating a national-level EROI. This is a mixed physical and monetary
approach using Multi-Regional Input-Output data and an energy extension. We discuss some
conceptual and methodological issues relating to defining EROI for a national economy, and describe
in detail the methodology and data requirements for the approach. We obtain initial results for the UK
for the period 1997–2012, which show that the country’s EROI has been declining since the beginning
of the 21st Century. We discuss the policy relevance of measuring national-level EROI and propose
avenues for future research.

Image
Figure 1. Types of EROI. EROIstnd: standard EROI. EROIpou: EROI at the point of use. EROIext: extended EROI.

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FOOD AND EROEI

Thankfully, the EROEI and EcoE concepts are getting increasing attention elsewhere (as the citations listed a few posts back suggest). And the attention does seems to be of reasonable quality given the peer-reviewed outlets. So, the conversation is moving forward. Just elsewhere for now.

I would be thankful for advice on which other websites do a decent job of discussing the EROEI/EcoE notion.

(1) I’ve been following Morgan’s https://surplusenergyeconomics.wordpress.com for some time now. The SEEDS system underlying his work hasn’t been published yet; so, for now, it lacks peer-review. But the basic concept is straightforward, his explanations (and responses to questions) are clear and concise, and he’s, slowly, been more forthcoming with details. For now, it has face validity. But more validation is needed.

(2) I’ve been hunting for information on the EROEI of food systems (at various scales and scopes). There’s work by Canning et al. (2010) for the USDA. An image from the work:
Image
Years ago Eric Garza posted some work. There’s the shell of his work at But most stuff seems gone or behind a wall.

2015 – There is a short piece by Garza at … or-web.pdf

2013-2014 – Resilience.org had an archive of Garza’s work: http://www.resilience.org/tag/eroeioffoodproduction/ But he asked that they remove the posts. Not sure what to make of that. I’ve tried to contact him without a response so far.

Other food EROEI sites:

2019 info: … roduction/

2018 info: https://georgejetson.org/eroi-of-food-production/

2011 info: … d-on-food/

2010 info: … -food.html

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I think that you are missing the point Adam. The issue is about applying the concept of EROEI to the hydrocarbon-dependent industrial food system. Something that the CSS document https://css.umich.edu/publications/factsheets/food/us-food-system-factsheet … -factsheet) highlights. Although they do not use the term EROEI or EcoE, their diagrams and text are about those concepts. It’s hard to read their image at https://www.resilience.org/wp-content/u … 24×768.jpg without seeing EROEI/EcoE at work.

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My interest in EROEI and EcoE is not constrained to their application to the oil and gas industry (I have no expertise whatsoever in that industry. Only what I’ve picked up here, at http://peakoilbarrel.com/, and at TOD years ago). I’ve always had more interest in its application to food systems. But, as you know, most of the development of these metrics has been focused on oil and gas. The extended-EROEI notion is relevant to food. And Morgan’s EcoE is almost entirely about understanding the entire economy as an energy system (not a financial system), and thus applies to the food system. Lately, Morgan’s mentions food insecurity more and more, as a consequence of a rising EcoE.

When I find a new research publication applying EROEI/EcoE to food systems, I’ll post it here. But the two opening entries do have a food connection.

(1) The opening article has a focus on life cycle assessment (LCA). (This is the same framework used by the CSS folks in analyzing the US food system.) It was useful because it has an “upstream/downstream” perspective, instead of just looking at one end of a system. That perspective is important when looking into the food system.

(2) The second article I included is about socio-economic systems and includes discussion of EROEI. I trust you’d agree that gets close to food systems.

Rigo E. Melgar-Melgar & Charles A.S. Hall (2020) Why ecological economics needs to return to its roots: The biophysical foundation of socio-economic systems. Ecological Economics, 169, March 2020, 106567.
DOI: 10.1016/j.ecolecon.2019.106567
… via%3Dihub

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References

Xxxxx, X. (xxxx). Xxxx Xxxxxxxx. Xxxxxxxx, Xxx Xxxxxx, XX.

Raymond De Young
School for Environment and Sustainability
University of Michigan, Ann Arbor, MI 48109

Updated: March 1, 2020

Copyright © 2020 Raymond De Young, All Rights Reserved.