Energy Return on Energy Invested – Prof. Charles Hall’s Comments

In my most recent post, Why the Standard Model of Future Energy Supply Doesn’t Work, I made some comments about the calculation of Energy Returned on Energy Invested. Professor Charles Hall sent me the following response to what I said, which he wanted to have published. I have a few follow-up comments, but I will save them for the comments section.

Section of Why the Standard Model of Future Energy Supply Doesn’t Work Upon Which Comments Are Being Made

The Energy Return on Energy Invested (EROEI) Model of Prof. Charles Hall depended on the thinking of the day: it was the energy consumption that was easy to count that mattered. If a person could discover which energy products had the smallest amount of easily counted energy products as inputs, this would provide an estimate of the efficiency of an energy type, in some sense. Perhaps a transition could be made to more efficient types of energy, so that fossil fuels, which seemed to be in short supply, could be conserved.

The catch is that it is total energy consumption, that matters, not easily counted energy consumption. In a networked economy, there is a huge amount of energy consumption that cannot easily be counted: the energy consumption to build and operate schools, roads, health care systems, and governments; the energy consumption required to maintain a system that repays debt with interest; the energy consumption that allows governments to collect significant taxes on exported oil and other goods. The standard EROEI method assumes the energy cost of each of these is zero. Typically, wages of workers are not considered either.

There is also a problem in counting different types of energy inputs and outputs. Our economic system assigns different dollar values to different qualities of energy; the EROEI method basically assigns only ones and zeros. In the EROEI method, certain categories that are hard to count are zeroed out completely. The ones that can be counted are counted as equal, regardless of quality. For example, intermittent electricity is treated as equivalent to high quality, dispatchable electricity.

The EROEI model looked like it would be helpful at the time it was created. Clearly, if one oil well uses considerably more energy inputs than a nearby oil well, it would be a higher-cost well. So, the model seemed to distinguish energy types that were higher cost, because of resource usage, especially for very similar energy types.

Another benefit of the EROEI method was that if the problem were running out of fossil fuels, the model would allow the system to optimize the use of the limited fossil fuels that seemed to be available, based on the energy types with highest EROEIs. This would seem to make best use of the fossil fuel supply available.

Charlie Hall responds:

I have always been, remain and will probably always continue to be a huge fan of Gail Tverberg, her analyses and her blogs. I am also committed to try and make sure science, such as I understand it, remains committed to truth, such as that is possible, which includes an accurate representation of the scientific work of others. In that spirit I wish to correct a short piece (referenced above) that is attempting to represent my own work on Energy Return on Investment (EROI or EROEI) but does not do so in a way that is fully consistent with the published work of myself and my colleagues.

I define EROI as a simple ratio, not a model, but have no particular concern about Gail’s use of the word model other than that it may imply something more complicated than it is. EROI is an observational tool for analysis, not a model with an objective in mind. My perspective is summarized in my 2017 book “Energy Return on Investment: A unifying principle for Biology, Economics, and Sustainability” although my approach is consistent throughout my published work with occasional small additions as our understanding expands, changes in available data occur or new questions arise. For example my methods going as far back as Cleveland et al. 1984 and Hall, Cleveland and Kaufmann (1986) are available for anyone to see and virtually the same as those in Murphy et al. 2011 and Hall 2017. The field is rich and very active today, with an entire well-funded and attended four day meeting at the French Institute of Physics at Les Houches dedicated to EROI last year, a two day session on petroleum (including many papers on EROI) at the American Chemical Society in New Orleans a month ago, and many very interesting publications by, for example, Carey King, Marco Raugui, Adam Brandt, Mohammed Masnadi, Victor Court and Florian Fizaine among many others.

As others increasingly used EROI there became increasingly different approaches used, so, in order to generate a consistent nomenclature and basis for comparison (EROIstandard) while allowing flexibility and creativity in use we published a protocol for performing EROI analysis (Murphy et al. 2011; Carey King has also addressed making the nomenclature and methods more explicit). Sometimes EROI studies are not easily comparable due to limitations in data or philosophy (see point 3). This is not something that escapes EROI researchers and is widely discussed in the literature. Sometimes we have examined the reasons for different EROI’s in the literature (e.g. Hall, Dale and Pimentel). Another issue is that it is common for blogs and reporters to read more into the results of scientific publications on EROI than the authors sought to assess, and such false conclusions can move very quickly on the Internet.

I now address some of Gail Tverberg’s specific points (in bold):

1) “The catch is that it is total energy consumption that matters, not easily counted energy consumption”. To understand this one must begin with the definition of EROI, for example on page 66 of the above book:

As we define again and again we have used the direct (e.g. natural gas to pressurize an oil field) plus indirect (energy to make the capital equipment: see Fig. 6 legend of Cleveland et al.) energies that are used to exploit fuels from Nature. We have consistently defined EROI to mean energy at the wellhead, mine mouth, bussbar or farm gate unless explicitly stated otherwise. We consider the energy used subsequently to deliver or use that energy as efficiency (as in food chain efficiency) of the use system. These data are not easy to gain, requiring many months of research in many libraries and government archives (See Appendix 1 of Guilford et al.) and are becoming more difficult as much of our National data gathering erodes. Such difficulties and their consequences are usually referred to in peer-reviewed EROI research papers by the authors themselves.

2) “The standard EROEI method assumes the energy cost of each of these is zero.” This is most explicitly not true. As appropriate (and as we have become better at the analysis) we have included energy costs of taxes (e.g. Prieto and Hall), Roads (Hall, Balogh and Murphy; Prieto and Hall), labor (e.g. Hall et al 1986; Prieto and Hall) and so on. We have tended to avoid the contentious issue of whether or not to include labor as “input” or “consumption” but occasionally undertook it as sensitivity analysis.

Gail is correct in saying that there are many more costs associated with energy, and that these costs are extremely important to society. But we normally consider these as costs associated with use of energy, but not its extraction from Nature which is the point and definition of EROI analysis. We have considered these before as EROIpou, that is at the point of use, or more recently (and better in my opinion now) as the EROI (at the mine mouth) required to support various levels of societal well-being (e.g. education, health care, arts etc.; Lambert et al.). At the logical extreme we may wish to include all of civilization’s activities as supportive of the energy extractive process so that EROI would be (by definition) 1:1, but that does not seem useful to me. We need to know how much energy it takes to get each actual or potential energy resource. For example, with an EROI of close to 1:1 corn-based ethanol is not a net energy source to a modern complex society. The lower EROI of renewables after accounting for intermittency (see below) will make the transition to renewables, if that is possible, very difficult.

3) “The ones that can be counted are counted as equal, regardless of quality”. This is absolutely not true. We have considered quality exhaustively, and have even presented our results with and without quality corrections from our earliest publications (Cleveland et al., Hall et al.) through our most recent publications (Hall 2017 p. 133 etc.). Murphy et al. includes a sophisticated procedure called the Divisia index to correct qualities of input and output energy which we sometimes use in our results. The question of intermittency with wind and photovoltaic energy is a difficult issue repeatedly considered in EROI analysis although not fully resolved by the greater scientific community, but also clarified with the recent publications of Palmer (and Tverberg) for certain systems. Depending upon the penetration of renewables, including intermittency in the analysis greatly reduces the EROI of these technologies. Whether one corrects for the quality of energy output for these sources is best handled with sensitivity analysis.

EROI is not some flawed tool of the past, but a consistent yet evolving and improving tool becoming more and more important everyday as the depletion of our primary fuels continues and as replacement with renewables is increasingly considered. While EROI analysis is hardly precision science, mostly due to data limitations, nevertheless as I reviewed my older publications for this response I was impressed by the general consistency of our results (corrected for e.g. depletion over time) from 1979 and especially 1984 to present. A large problem is the erosion of the Federal support for, and hence quality of, the data of e.g. the U.S. Bureau of Census and the increasing use of EROI (and scientific analysis more generally) for advocacy rather than objective analysis and hypothesis testing. Essentially all credible analyses show a declining EROI of our principle fuels and a much lower EROI for those fuels we might have to replace them. The economic consequences are likely to be enormous. It continues to astonish me that there is essentially no Federal or other support for good, objective analysis of EROI and its implications. EROI is not only as important as when it was created it is critical now as we choose, or more likely will be forced into, making an energy transition. With appropriate support we have the conceptual and procedural tools to undertake needed analyses which can be an important tool in understanding and (with other tools) guiding our transition to renewable energy resources, if indeed that is possible.

Having said this I would like to point out where Gail does have a very good point. The amount of energy necessary to maintain the infrastructure within which our energy extraction industries can function (e.g. roads, schools, health care, perhaps civilization itself) is enormous and is not counted in my most of my studies as part of the investments to get the energy. OK good point. How to do this i.e. how to prorate this relative to e.g. all of the health care investments for all of the population? One might add up all of the labor in the appropriate energy industries, compare this to the total population and multiply the ratio by the total energy used in health care. Or one might assume that all of the energy required to support labor, including the energy associated with the depreciation of the worker (i.e. the energy used to support the family of the worker) is well represented by the worker’s salary. So if a worker makes $70,000 in a year one could multiply that by the mean energy intensity of the U.S. economy (about 6 MJ per dollar) to generate the energy used to support labor for year (420 GigaJoules, equal to about 70 barrels of oil). Again doing this for all energy workers would be a huge sum. When as part of sensitivity analysis we added in an estimate of the energy to support workers’ salaries for building solar facilities in Spain it doubled the energy cost of building and maintaining the PV structures and halved its EROI. The main point that I think Gail is making is that as our high quality fossil fuels are depleted and we contemplate shifting to renewable energies we will have a lower and lower net energy delivered to run the non-energy portion of society with very large consequences. I completely agree with this.

References (in chronological order – there are many more that could be added)

Hall, C.A.S., M. Lavine and J. Sloane. 1979. Efficiency of energy delivery systems: Part I. An economic and energy analysis. Environ. Mgment. 3 (6): 493-504.
Hall, C.A.S., C. Cleveland and M. Berger. 1981. Energy return on investment for United States Petroleum, Coal and Uranium, p. 715-724. in W. Mitsch (ed.), Energy and Ecological Modeling. Symp. Proc., Elsevier Publishing Co.

Cleveland, C.J., R. Costanza, C.A.S. Hall and R. Kaufmann. 1984. Energy and the United States economy: a biophysical perspective. Science 225: 890-897.

Murphy, David J., Hall, Charles A. S. 2010. Year in review—EROI or energy return on (energy) invested. Annals of the New York Academy of Sciences. Special Issue Ecological Economics Reviews: 1185, 102-118.

Murphy, D.J, Hall, C.A.S. 2011. Energy return on investment, peak oil, and the end of economic growth. Annals of the New York Academy of Sciences. Special Issue on Ecological economics. 1219: 52–72.

Hall, C.A.S., and Hanson, D. (Eds.) 2011. Sustainability: Special Issue on EROI

Murphy, D., Hall, C.A.S., Cleveland, C., P. O’Conner. 2011. Order from chaos: A Preliminary Protocol for Determining EROI for Fuels. Sustainability: Special Issue on EROI. 2011. Pages 1888-1907.

Guilford, M., C.A.S., Hall, P. O’Conner, and C.J., Cleveland. 2011. A new long term assessment of EROI for U.S. oil and gas: Sustainability: Special Issue on EROI. Pages 1866-1887.

Hall, C. A. S., Dale, B. and D. Pimentel. 2011. Seeking to understand the reasons for the different EROIs of biofuels. Sustainability 2011: 2433-2442.

Prieto, P., C.A.S. Hall. 2012 Spain’s Photovoltaic Revolution: The energy return on investment. Springer, N.Y.

Hall, Charles A.S., Jessica G. Lambert, Stephen B. Balogh. 2014. EROI of different fuels and the implications for society Energy Policy Energy Policy. 64,: 141–152.

Lambert, Jessica, Charles A.S. Hall, Stephen Balogh, Ajay Gupta, and Michelle Arnold. 2014. Energy, EROI and quality of life. Energy Policy Volume 64: 153-167

Hall, C.A.S. 2017. Energy Return on Investment: A unifying principle for Biology, Economics and sustainability. SpringerNature N.Y.

Palmer, G. 2017, A Framework for Incorporating EROI into Electrical Storage, BioPhysical Economics and Resource Quality, vol. 2, no. 2

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About Gail Tverberg

My name is Gail Tverberg. I am an actuary interested in finite world issues - oil depletion, natural gas depletion, water shortages, and climate change. Oil limits look very different from what most expect, with high prices leading to recession, and low prices leading to financial problems for oil producers and for oil exporting countries. We are really dealing with a physics problem that affects many parts of the economy at once, including wages and the financial system. I try to look at the overall problem.

381 thoughts on “Energy Return on Energy Invested – Prof. Charles Hall’s Comments

  1. “Some analysts have described the African debt situation as a ticking time bomb. In fact, an upcoming paper from Brookings argues that the IMF and World Bank haven’t rung the debt alarm bell loudly enough. Brookings claims they won’t do so until at least one of Africa’s big five economies—Nigeria, South Africa, Angola, Ethiopia, or Kenya—becomes debt distressed.”

    • It sounds like everything is proceeding as planned, and is working out just like the IMF and the western bankers want it to.

    • It is hard to get much growth without an increase in per capita energy consumption. Africa has been awfully flat and awfully low, when it comes to energy consumption.

    • China is one of the areas I worry about. I don’t remember seeing the 15% to 17% of the economy being spent on interest previously.

      China already has way too much real estate that people cannot afford. They cannot afford either higher interest rates or higher oil prices; they certainly cannot afford both. Their electricity system is badly losing money, because of a combination of electricity price caps and coal prices that need to rise, if coal mines are to be economic. See this WSJ article Coal Is About to Lose Face in China.

      • According to David Stockman, China is a powder keg waiting to go off. As he explains, if you think the US is in bad shape, China is several times worse off and it appears the global community has little interest in the Yuan as a global reserve currency. It’s circulation is roughly 1.2% of the global reserve currency pie, only beating the Swiss Franc at 0.2%.

        • Mr. David Stockman, notable “serial worrier” a side, yep that’s a point I try to hammer out frequently, basically the rich of any strata and aspiring to upper status (most people) are just starring at perceived wealth structure, which stands around $ and its derivatives.

          The world is completely nuts, e.g. few decades have passed, napalm is forgotten, and the Vietnamese would prefer US over China, given the above materialistic urges inside predominant global environment, plus some older cultural animosities..

          • Nuts, totally: and completely natural too.

            The wired-in hierarchical prejudices of the human animal (in common with other mammals) – the normal base to which we always return, and which we symbolise in the things which animals cannot make.

            All the various isolated Socialist revolutions of the 20th century invariably produced a monarch, court and privileged higher-consumption class…..

            We can also recall the avidity with which the upper classes of the Celts and Germans fell on the products of Rome: wine and other luxury goods, even using Roman coins apparently not for true commercial exchange – the local economy was to primitive – but in displays of prestige.

  2. “Despite having the greatest oil reserves in the world, Venezuela’s government is being forced to spend millions of dollars a day importing crude to prop up its ailing industry. Petrol remains the only cheap commodity left in Venezuela amid the collapse of most of its economy, but the oil industry is now also struggling to meet basic domestic demands.”

    • This shows how ridiculous the concept of reserves is. Reserves depend on sufficiently high prices as well as a whole system for using the crude.

        • The devil is in the details. It sounds like the gas will be Russia’s to sell, if they produce it. Not clear how much taxes they will need to pay and other details.

          • “Rosneft will have the right to sell all of the fields’ production for export, including in the form of liquefied natural gas, the Rosneft statement said.

            It said total estimated reserves at the two fields are 180 billion cubic meters (bcm) of gas, and that maximum annual production would be 6.5 bcm.”

        • Recall as few years ago they were announcing interest in possibly contracting Russian NPP, so given the realities of today’s Venezuela I’d not give it much chance.

          However, developing at least regionally significant? natgas field there might have some legs afterall, either as standalone project or for helping to cook their heavy crude or something in between. Who knows..

        • True, but failing states can still export stuff, so…..

          I remember reading about people half-starved in the countryside in Argentina, while the produce was exported.

          • Argentina?
            I was just there– “half-starved”?
            Surely you must be on another planet.
            I’ve been traveling in SA from the 1970’s.

            • I have Argentinian relations, Duncan. It got very tough indeed -and violent – in some rural areas during the big crisis.

            • The 70’s rightwing dictatorship?
              Yea, it was real messy.
              The proletariat has seen all the means of governance, and has real time experience.
              (unlike some one party states, like the US)

    • but is there a method to his madness?

      I suspect that Harry is linking to articles about many troubled countries so that he can then end with a fantastic flourish…

      as he links to an article about the troubles of the UK…

      call me Sherlock…

      though I could be wrong…

      Harry, so how about it?

      bloody ‘ell, there’s gotta be at least one…

      • Harry doesn’t mind if he doesn’t make the scene. He’s got a day time job, he’s doin’ all right. He can play the honky tonk like anything. Savin’ it up for Friday night.

          • though, without the fake “s” on the end of his name…

            I suspect he’s the long lost 4th Bee Gee…

            • speaking of Harry…

              why didn’t Prince Harry pick Amber Heard?

              it’s an epic injustice…

              Princess Amber should have been the one…

              life can be so disappointing…

      • “I suspect that Harry is linking to articles about many troubled countries so that he can then end with a fantastic flourish… as he links to an article about the troubles of the UK…”

        Troubles? In the UK?! Our economy is purring along like one of our finely-tuned Rolls Royce engines, thank you very much! Although, come to think of it, BMW own that now. No matter – the laws of physics will prove no match for the guile and enterprise of the Englishman. All rise for the anthem!

        • ‘ I resisted all temptations, to belong to other nations! I am an Englishman, I am an Englishman!

          I could have been a Roossian, a Jew, a Turk, or Proossian; but I am an Englishman, I am an Englishman!’ Gilbert & Sullivan

          (Sorry Mr Gibbs,’Briton’ don’t rhyme!)

          Or my favourite:

          ‘Other races get in a funk, but Brits don’t, because we’ve got…… Spunk! Spunk, spunk, the Brits are full of Spunk!’ Barry Humphries. 🙂

        • bravo!

          and the guile of you Brits is only matched by that of us Yankees!


          pip pip! cheerio!

          Keep Calm and OFW…

  3. Russia Is Ready For Possible SWIFT Cutoff, Debt-Sale Ban
    ZH 4-17-2018

    “We have been tracking the ‘relationship’ between Russia and the international payments system SWIFT since 2013, when we first reported that the NSA had somehow implanted itself inside SWIFT, and had been tracking flows through the global USD-intermediated financial transaction system.

    It wasn’t long after this revelation that Russia started planning its own (possibly BRICS-based) global financial system in furtherance of its goal of de-dollarization.

    A year later, the UK demanded that the EU consider kicking Russia out of SWIFT as part of the sanctions levied in response to Russia’s purported activities in Ukraine.

    However, removing Russia from the system would carry certain risks, since it would create the opportunity for Russia to demonstrate that it can survive without SWIFT, possibly inspiring other countries to follow its lead.”

    “But in addition to Russia’s preparations for leaving SWIFT, the country’s central bank said Tuesday that it has a plan for monetizing Russian debt should the US prevent Americans and others who want to maintain their access to the US financial system from trading in Russian debt instruments.

      • Why waiting for such outlier scenario, Russian exports are mostly linked to German’s natgas hub, their primary customer, so there is no incentive to do that.. at least for the near-mid term.. They can’t even completely starve out parts of CEE (e.g. going pro US nuts) since there have been constructed new interconnectors from Germany, as to feed their factories-colonies.

        So if you ask again properly, is it possible to selectively kick out Scandinavia and UK, while still sending natgas to Germany? I don’t know for sure, most likely it should be possible to arrange it like that.

          • hello, this is Russia…

            we seem to be having a technical problem with sending gas through to you guys…

            but, don’t worry…

            we should have it fixed in a week or so…

            thanks for your understanding…

    • ” the NSA had somehow implanted itself inside SWIFT”
      The best reference for this is “The Last Circle” by Cheri Seymour.
      It is alleged, among other things, that the US Government “acquired” the PROMIS software, added one or more backdoors, adapted it for use with banking, and other personnel based applications and sold it to unsuspecting governments, banks etc via third parties. Versions post 1982 were managed by: the NSA; the CIA; and a foreign inetelligence service. A later (perhaps unrelated) version was mentioned in 911 interviews. The book also mentions “SWIFT” chips, re IIRC, encryption.

  4. “[European] Auto sales dropped in March at eight of the 10 top-selling carmaking groups, with the steepest declines at Ford Motor Co., Fiat Chrysler Automobiles NV, BMW AG and Nissan Motor Co., the ACEA said. The slide has been particularly acute in the U.K., where car sales were down 16 percent in March and 12 percent for the quarter.”

    • “Car finance has largely been shielded from the fines, headlines and scrutiny that have peppered the banking sector in recent years. However, attention is now turning to a market that represents a significant share of consumer debt in many developed economies. The UK’s Financial Conduct Authority (FCA) has announced an investigation into the industry and regulators in other countries have expressed concerns. Further pressure may come from rising borrowing costs as interest rates rise, intensifying financial problems.”

      • I am sure lease rates will rise with interest rates as well. These have been a low-cost approach for some people.

        The increase in interest rates has been in short term interest rates, but I believe these are what affects auto loans.

  5. Thanx Gail and Charlie to point out your views on current EROI definitions.
    Charlie wrote “So if a worker makes $70,000 in a year one could multiply that by the mean energy intensity of the U.S. economy (about 6 MJ per dollar) to generate the energy used to support labor for year (420 GigaJoules, equal to about 70 barrels of oil). Again doing this for all energy workers would be a huge sum.”

    Would it be a good idea to convert all costs to energy?

    for example using a formula, such as:

    E = c * P

    E = estimated energy invested (Kwh)
    c = a constant factor (Kwh/Dollar)
    P = price of a product that generates energy output (Dollar)

    So that “huge sum” could become very simple. And mainly we could focus on that “constant” factor c. This factor is probably not constant over time and also strongly dependent on the (world-wide average) Kwh production price or other .

    c could for example be estimated as c=w/k where
    k= worldwide average (net) price of 1 kwh currently ≈ 0.04 dollarcent
    w = a welfare factor, which part of our welfare is due to cheap (fossile) energy. I guess at least 80%. Or in other words: How much “welfare” dit the average world citizen have in, let’s say the year 1800? And how much did we win since then?

    My best guess is c ≈ 20
    Definitely worth a discussion!

    Also still worth a discussion: is P the selling price with or without tax and subsidy. And with or without seliing margins.

    But with such a working formula the math would be much easier to calculate an EROI? Agree?

    This formula already helped me to decide not to buy solar panels on my roof.

    • I didn’t buy solar panels because a Pole was trying hard, really hard, to sell them to me…..

    • Interesting thoughts! Solar panels are definitely a high-cost product, producing something that is close to a substitute for natural gas or coal (because of its intermittency). When we think of it that way, the wholesale cost per kWh is more in the $.02 to $.03 range per kWh, making the comparison even worse.

      Part of the question is whether in total, all energy products are adding enough energy growth to the economy to maintain necessary economic growth. If we look at the US economy, we see this pattern in GDP growth and 10 year treasury interest rates.

      (Chart produced by Federal Reserve of St. Louis (FRED) showing a comparison 10 year treasury interest rates and the annual change in GDP rates (where GDP growth includes inflation).)

      Clearly there has been a very long downtrend in rate of return of both, suggesting that the current level of energy growth is not enough. (World data would show something similar, except recent world data is more distorted by “fake” GDP growth, IMO.) The economy is growing less and less quickly, in response to less and less energy consumption growth (not shown on this chart). Rates of return are lower as well.

      • Thanx for your comment. I’m not sure my formula E = c * P als explains GDP growth and energy growth are strongly related. The basic idea was to calculate energy invested not leaving out any money-involved component, for example building the dock that built the ship that transports the product overseas.

    • But what adverse effects does the plastic eating enzyme have? If nothing else, creating this enzyme and distributing it adds a new layer of costs to “protecting the environment.” If we used the self-organized system of plants and animals, the waste products of one system would be inputs of the next system. Instead, we add a new layer of costs to the system. We also don’t know how the broken down products affect the environment–certainly better than plastic, but do they add a different kind of pollution?

    • this is bullshit here why

      These enzymes work well on amorphous PET, but commercially PET is highly crystalline – in fact my reading of the literature it is possible that crystalline PET is never broken down by enzymes.

      Recycled PET pellets currently cost more than virgin PET. This is because collection, separating, cleaning, remelting etc is expensive. This makes this technology a non-starter at present though economics will change in future.

      The enzymes are used in dilute broths (to avoid product inhibition or deactivation of the enzymes). That makes a huge energy cost in extracting the monomers back again

      PET is a small part of the plastic waste stream – PE or PP accounts for 90%

      PET is one plastic that can be and is recycled either chemically or by just remelting the plastic into lower grade applications (e.g. matting)

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