Category Archives: Reviews

Thanatia Book Review

This is the pre-peer-reviewed version of the following article:

Thanatia: The Destiny of the Earth’s Mineral Resources: A Thermodynamic Cradle-to-Cradle Assessment by Antonio Valero Capilla and Alicia Valero Delgado. 2014. ISBN: 978-981-4273-93-0. 672pp. World Scientific Publishing Company: Hackensack, NJ, USA. $158.00 (hardcover).


The review has been published in final form at

Antonio Valero Capilla and Alicia Valero Delgado are both well-known authors in the area of thermoeconomics – a school of heterodox economics that makes use of the laws of thermodynamics to account for the cost of natural resource use in the form of energy, entropy, or exergy, and helps to point out irreversibilities in production systems. Their latest book centers on a simple but important concept: ‘Exergy replacement cost’ as the exergy required given currently available technology to return a mineral resource from a completely dispersed state, termed “Thanatia”, to the physical and chemical conditions currently present in nature. Exergy originates from the second law of thermodynamics and is defined as the “maximum work that can be obtained from a system when it reaches equilibrium with a reference environment (R.E.)”. The concept of replacement cost (or thermodynamic rarity) attempts to highlight the exergy bonus of today’s naturally-occurring mineral deposits and how much it would cost society (in exergy terms) to restore minerals back to their original state in nature (at typical ore grades in today’s mineral deposits). This helps to incorporate a “grave-to-cradle” perspective into mineral resource assessments.

Today’s societies with their concentration of modern technologies, low-carbon transportation and renewable energy systems, demand enormous quantities of base metals (e.g., iron, copper, aluminum) as well as nearly all of the minor or scarce metals of the Periodic Table of the Elements in order to ensure proper functioning and performance (Greenfield and Graedel 2013; Graedel and Erdmann 2012). As a result, the issue of resource scarcity and criticality has gained substantial interest in recent years (Graedel et al. 2015; EC 2014, 2010; IW Consult 2011; BGS 2012; Morley and Eatherley 2008). There is also an ongoing discussion in the area of life-cycle assessment (LCA) as to how mineral resources should be evaluated in the life-cycle impact assessment (LCIA) stage (Klinglmair et al. 2013; Mancini et al. 2013; Vadenbo et al. 2014). The use of thermodynamic indicators has so far played only a minor role in the evaluation of mineral resources. With regard to exergy, the analysis is often time-consuming and difficult to understand, and establishing a proper R.E. (Szargut 1989) for exergy evaluations of mineral resources can be difficult (Gößling-Reisemann 2008). Furthermore, when compared to fossil fuels, non-fuel minerals consistently have lower exergy values resulting in wrong conclusions with regard to their value in the system analyzed (Gößling-Reisemann 2008; Valero and Valero 2015).

The book authors propose to overcome these challenges by defining Thanatia (from the Greek word θάνατος “death”) as a possible baseline environment to which currently existing mineral deposits can be compared. Thanatia is seen as a possible end to the “Anthropocene” period (Crutzen 2006) in which all concentrated materials have been extracted and dispersed throughout the crust and all fossil fuels have been combusted (Valero et al. 2011a, 2011b). The total mineral exergy of a mineral substance is then calculated as the sum of chemical exergy, concentration exergy, and comminution exergy. Only chemical exergy is calculated relative to the R.E., while both concentration and comminution exergies use Thanatia as a baseline. In contrast to traditional exergy analysis (which typically only look at one chemical substance per chemical element in the R.E. and do not account for their concentration), the approach proposed by Valero and Valero incorporates the typical mineral concentrations of a mine (i.e., today’s ore deposits provided by nature) and that of the average concentration in the Earth’s crust (i.e., Thanatia). This allows quantification of the ‘hidden’ exergy cost associated with decreasing the concentrated state of minerals in natural deposits though extraction, production, manufacture, use, and ultimate dispersion (e.g., via dissipation or landfilling). It sends a warning message that not every mineral that is being dispersed may be replaceable (because of high exergy replacement costs).

The book by Valero and Valero provides a thorough summary of the authors’ pioneering work over several years[i] using exergy as a measure in resource evaluations (Valero and Valero 2013, 2015). The reader will be impressed by the breadth of the book, discussing in great detail the need for incorporating thermodynamics into resource evaluations, their idea of defining an alternative baseline environment (the Crepuscular Earth Model or Thanatia), and a thorough summary of data sources and assumptions made to obtain the energy replacement cost of important industrial minerals. Thanatia has 17 chapters – each with a brief summary at the end. The first four chapters provide justification for using exergy-based analysis in resource evaluations and explain basic thermodynamic concepts in an easy-to-understand format. Chapters 5 to 8 provide a concise summary of the geochemistry of the earth, resources of the earth, and an introduction to mining and metallurgy as well as the production of key minerals and literature estimates of associated energy requirements. These chapters discuss aspects of the traditional ‘cradle-to-grave’ view of today’s metal production system. The chapters can be skipped by readers already familiar with the basic concepts of mineral geology and metallurgy. The third part of the book from chapter 9 to 13 represents the core of the book. Here the details of exergy accounting and the design of the Crepuscular Earth Model (Thanatia) are described. The chapters are based on numerous scientific publication published by the authors in recent years (e.g., (Valero and Valero 2013; Valero et al. 2011b, 2011a; Valero and Valero 2015; Valero et al. 2015)). Finally, chapters 14 to 17 provide reflections on the challenges of resource depletion and discuss options to slow resource depletion (e.g., via recycling and resource efficiency measures).

Thanatia is a ‘timely’ book that contributes new ideas to the debate on how to quantify resource depletion. It is thereby relevant to researchers working in the field of sustainable resource management and resource criticality. It points out some of the “weak-points” of current assessment methods focusing solely on a “cradle-to-grave” system boundary, thereby not accounting for the cost of irreversibly losing substances via means of dissipation and ultimate disposal. The book also communicates interesting ideas on using exergy as an alternative for allocation in LCA (Valero et al. 2015). In my view, some of the data reported on the exergy and exergy replacement cost of several important industrial minerals could, in a next step, be incorporated into preliminary LCIA methods or increasingly combined with results from criticality studies published elsewhere (Graedel et al. 2015; EC 2010, 2014; IW Consult 2011; BGS 2012; Morley and Eatherley 2008). This would also make the material available to a wider audience. However, the book is unfortunately also written dense in repetitions and contains lengthy explanations of the thermodynamic concepts used. This makes it difficult to read at times and does not always help to ‘demystify’ the concept of exergy (a stated goal of the authors). Incorporating more figures to visualize the concepts use and explanations with the existing figures and graphics provided would make the book more accessible and less tedious to read.

Overall, this is a valuable collection of papers and supplemental information of the authors over the last years leading to the model of Thanatia. It is a practical, refreshing complement to the growing number of academic papers on the topic of mineral resources that will help to highlight the importance of thermodynamic concepts in natural resource evaluations.

-Philip Nuss, Yale University, New Haven, CT, USA



BGS. 2012. Risk list 2012: An updated supply risk index for chemical elements or element groups which are of economic value. Nottingham, United Kingdom: British Geological Survey.

Crutzen, P.J. 2006. The “Anthropocene.” In Earth System Science in the Anthropocene, ed. by Professor Dr Eckart Ehlers and Dr Thomas Krafft, 13–18. Springer Berlin Heidelberg. Accessed August 14, 2015.

EC 2010. Critical raw materials for the EU. Report of the Ad-hoc Working Group on defining critical raw materials. Brussels, Belgium: European Commission (EC). documents/index_en.htm. Accessed December 27, 2012.

EC 2014. Report on Critical Raw Materials for the EU. Report of the Ad-hoc Working Group on defining critical raw materials. Brussels, Belgium: European Commission (EC). Accessed June 10, 2014.

Gößling-Reisemann, S. 2008. What Is Resource Consumption and How Can It Be Measured? Journal of Industrial Ecology 12(1): 10–25.

Graedel, T.E. and L. Erdmann. 2012. Will metal scarcity impede routine industrial use? MRS Bulletin 37(04): 325–331.

Graedel, T.E., E.M. Harper, N.T. Nassar, P. Nuss, and B.K. Reck. 2015. Criticality of metals and metalloids. Proceedings of the National Academy of Sciences 112(14): 4257–4262.

Greenfield, A. and T.E. Graedel. 2013. The omnivorous diet of modern technology. Resources, Conservation and Recycling 74: 1–7.

IW Consult. 2011. Rohstoffsituation Bayern – keine Zukunft ohne Rohstoffe: Strategien und Handlungsoptionen (Raw materials situtation in Bavaria – no future without raw materials: strategies and opportunities of action). IW Consult GmbH Köln. Accessed September 17, 2013.

Klinglmair, M., S. Sala, and M. Brandão. 2013. Assessing resource depletion in LCA: a review of methods and methodological issues. The International Journal of Life Cycle Assessment: 1–13.

Mancini, L., C. De Camillis, and D. Pennington. 2013. Security of supply and scarcity of raw materials. Luxembourg: Publications Office of the European Union.

Morley, N. and D. Eatherley. 2008. Material Security: Ensuring resource availability for the UK economy. Chester, UK: Oakdene Hollins, Ltd. Accessed September 17, 2013.

Szargut, J. 1989. Chemical exergies of the elements. Applied Energy 32(4): 269–286.

Vadenbo, C., J. Rørbech, M. Haupt, and R. Frischknecht. 2014. Abiotic resources: new impact assessment approaches in view of resource efficiency and resource criticality—55th Discussion Forum on Life Cycle Assessment, Zurich, Switzerland, April 11, 2014. The International Journal of Life Cycle Assessment 19(10): 1686–1692.

Valero, A., A. Agudelo, and A. Valero. 2011a. The crepuscular planet. A model for the exhausted atmosphere and hydrosphere. Energy 36(6). ECOS 2009: 3745–3753.

Valero, A., A. Domínguez, and A. Valero. 2015. Exergy cost allocation of by-products in the mining and metallurgical industry. Resources, Conservation and Recycling 102: 128–142.

Valero, A. and A. Valero. 2013. From Grave to Cradle. Journal of Industrial Ecology 17(1): 43–52.

Valero, A. and A. Valero. 2015. Thermodynamic Rarity and the Loss of Mineral Wealth. Energies 8(2): 821–836.

Valero, A., A. Valero, and J.B. Gómez. 2011b. The crepuscular planet. A model for the exhausted continental crust. Energy 36(1): 694–707.

[i] A summary of related literature is also available from the Exergoecology portal at


You can find the book reviewed in this article at the following website:

Book Review: “The Elements of Power”

20151120_Elements of Power by David S Abraham

Image taken from Yale University Press

The book “The Elements of Power” by David S. Abraham discusses our increasing dependence on many of the rare (minor) metals used in modern technology. In eleven chapters, the author discusses the importance of (rare) metals to modern technology (e.g., energy, communication, infrastructure, and defense), historical developments that led to increasing metals use, environmental issues of metals production (mining, refining, and smelting), and expected future trends in metal demand (e.g., increasing use of renewable energy technologies and associated metal requirements). The author describes in several short stories and anecdotes the crucial role of the minor metals in today’s technologies and argues that their complex production chains, finite supplies, and geological distribution, have the potential to result in supply disruptions and geopolitical conflicts in the near future. Abraham concludes that, unless we better understand the metals basis of modern society, shifting to renewable energy systems, hybrid cars, and smart grids, is likely to lead to burden shifting and unintended (environmental) consequences. The discussions bring up a number of important aspects of today’s metal production system, namely (1) the issue of companion metal production which can lead to imbalances in supply and demand, (2) the problem of low recycling rates for many of the metals (in this context Abraham correctly cautions that we will not be able to “recycle” ourselves out of the problem of a finite metals supply), (3) increasing supply chain complexities and trade relationships which make companies (and countries) more vulnerable to supply restrictions, (4) environmental implications of metals production, and (5) market dominance for several minor metals (e.g., niobium, rare earth metals, platinum grade metals) by only a few companies or countries worldwide. The author calls for more metals research and better education in materials science and metallurgy to address these problems.

The book is written for a popular audience and Abraham is able to discuss a multitude of complex topics of today’s metal production system in an engaging and interesting manner. Describing his own experiences and encounters with actors of the metals world, e.g. talking with metals traders, miners, product developers, and traveling to mines and production sites around the globe, helps to keep the topics fluid and interesting. The book represents, in my view, an important attempt to communicate the issues of metals resources to a wider popular audience, thereby increasing people’s awareness of resource issues and the use of metals in modern technologies we all depend on.

I am not aware of similar popular science books on the topic of metal resources and criticality. The UNEP Resource Panel has picked up the topic of metals in various reports that have been published since 2011. These are semi-scientific reports that discuss topics such as (1) metals stocks in society, (2) recycling rates of metals, (3) environmental impact of metals, (4) geological metal stocks, (5) future demand for metals, and (6) critical metals and metal policy options. Resource issues are discussed in the context of other research efforts, e.g., on decoupling economic growth from resource use, or biotic resources (biomass). These reports can be found at

Furthermore, the ‘Critical Materials Handbook’ by Gus Gunn was recently published by Wiley in an attempt to summarize some of the information on elements deemed important (in terms of their supply risk, environmental implications, and vulnerability to supply restriction by so called “criticality assessments” ( However, the book by Gus Gunn is more geared toward a scientific audience interested in learning more about a specific element or metal group. Therefore, I don’t think there are any competing books in the public realm at the moment.

I feel that the manuscript will act as an important communication tool between the world of “metals researchers” and the general public. It is written on a timely and very important topic and has the potential to increase public awareness, knowledge, and interest in the wider topic of ‘abiotic resources’ and interconnected metals supply chains.

-Philip Nuss, Yale University, New Haven, CT, USA

You can find the book reviewed in this blog at the Yale University Press website:

LCA Book Review

This is the pre-peer-reviewed version of the following article:

Nuss, P. 2015. Book Review: Life Cycle Assessment Handbook: A Guide for Environmentally Sustainable Products, edited by Mary Ann Curran. Hoboken, NJ, USA: PB – John Wiley & Sons, Inc., and Salem, MA, USA: Scrivener Publishing LLC , 2012, 611 pp., ISBN 9781118099728, $199.00 (paper), $159.99 (e-book). Journal of Industrial Ecology 19(1): 167–168.

The review has been published in final form at


This book by Mary Ann Curran constitutes an ambitious attempt to present the current “state-of-the-practice” in life cycle assessment (LCA). LCA started out as an approach to assess the environmental implications of products, and has to date evolved into a standardized method for systematically evaluating the potential environmental impacts of products, services, and technologies. Moreover, recent efforts have focused on expanding the LCA methodology also to capture indirect effects through the use of economic techniques and models (consequential LCA), and attempt to broaden the traditional LCA framework to integrate environmental, social, and economic aspects into the analysis, also referred to as life cycle sustainability assessment (LCSA). The reader will be impressed by the breadth of topics covered in this book, opening with an introductory chapter on “hot topics” such as, e.g., links of the LCA framework to environmental policy making, or the feasibility of LCA to address questions not only at micro (product) level but also at macro scale. This sets the stage for the subsequent chapters that can be divided into four sections: LCA Methodology and Current State of LCA Practice (Part I), LCA Applications (Part II), LCA in the Context of Decision Making and Sustainability (Part III), and Operationalizing LCA (Part IV). Curran has integrated a series of contributions by leading experts from academia, industry, and LCA consultants into the book. This created some repetition and left some topics unexplained, but the overall message and flow of content was clear and coherent. In particular, I enjoyed the diverse contributions from authors discussing the LCA framework from different professional perspectives. This resulted in an interesting mix of chapters, some of which deal with latest advancements in LCA methodology (e.g., integration of ecosystems goods and services, social LCA, LCSA, LCA and multi-criteria-decision analysis (MCDA)), while other chapters discuss practical applications (e.g., comparison of LCA software tools, LCA in product innovation, the use of LCA in sustainable supply chain management).

Chapters 2 to 6 deal with the four stages of an LCA (goal & scope, inventory analysis, impact assessment, and interpretation), briefly discuss the history of LCA, and provide an outlook to potential future developments. These chapters provide a concise overview of the latest impact assessment methods (Chapter 4) and inventory databases (except for example, ecoinvent 3 or the Social HotSpots Database – both were released after publication of this book) (Chapter 5), as well as software tools and smart data management techniques (Chapter 6). It should be noted, however, that these chapters are not a “how to” guide with instructions for carrying out an LCA. They instead provide a brief overview of a specific topic (e.g., life cycle impact assessment), and then elaborate on methodological challenges and open questions, and provide an overview of currently available models, data sources, and developments. For readers new to the LCA methodology, I would therefore recommend also to consult one of the many LCA texts available elsewhere (see for example, (Guinée 2002; U.S. EPA 2006; EC JRC 2010; Baumann and Tillman 2004)).

The phases of LCA (Source: UNEP)

Through a range of case studies, chapters 7 to 17 then continue to explore how typical methodological issues have been treated in various applications of LCA. These chapters provide the reader with case studies, for example, on modeling the agri-food industry in LCA and related challenges in data collection (chapter 7). Exergetic LCA (Ex-LCA) and its application to an advanced hydrogen process driven by nuclear energy is presented by Rosen, Dincer, and Ozbilen in chapter 8, who highlight differences of Ex-LCA in comparison to traditional LCA impact categories. Following this, Landers, Urban, and Bakshi discuss the integration of ecosystem goods and services, such as fresh water, soil, carbon and nitrogen cycles, and pollination, essential to all human activities, into ecologically based LCA (eco-LCA, chaper 8). Different ecosystem services are compared using exergy and emergy estimates and the authors emphasize the need for including natural capital in the analysis to avoid burden shifting. Other chapters deal, for example, with the application of LCA to waste management (chapter 11), buildings (chapter 14), and green chemistry and engineering (chapter 17). Each chapter is self-contained so readers can skip to topics of greatest interest to them.

Chapters 18 to 22 discuss how LCA supports decision making and sustainability. The chapter by Potting et al (chapter 18) compares four methods that allow assessment of human health and environmental impacts, namely technology assessment, environmental impact assessment, risk assessment, and LCA. The authors give a brief, yet interesting, overview of their overlaps, differences, and complementary approaches. The use of MCDA to help structure normalization and weighting during the impacts assessment stage of an LCA is introduced by Prado, Rogers, and Seager (chapter 19). This chapter provides a critical discussion of using external normalization and weighting factors in comparative LCAs that may be part of a pre-designed impact assessment method. The next two chapters build nicely on each other by first introducing how social aspects may be integrated into the LCA framework under the umbrella of social LCA (Benoit, chapter 20), and then by discussing the concept of LCSA (Zamagni et al, chapter 21), which aims at broadening the scope of indicators (environmental, social, and economic) and proposes to shift from individual product systems to larger units of measurement (e.g., whole product baskets, economic sectors, or whole economies). Although life cycle cost (LCC) analysis and consequential LCA are mentioned several time in this section of the book (as well as in chapter 1), I felt that a deeper discussion of these topics was missing and would have provided valuable information to allow the reader to better follow the overall discussion. A comprehensive review of consequential LCA is given, e.g., in (Earles and Halog 2011) and LCC is discussed in (Hunkeler and colleagues 2008). Chapter 22 by Stevenson and Ingwersen provides a review of environmental product claims in LCA according to the ISO 14020 series and includes an appendix that summarizes, amongst others, activities in the development of product category rules (PCRs) and environmental product declarations (EPDs).

Finally, chapters 23 to 25 conclude by looking at the role that life cycle information, in the hands of governments, industry, and consumers, can have in recognizing environmental performance and avoid shifting of environmental burdens. In this context, chapter 23 by Ramjeawon looks at capacity building for LCA in developing countries, and chapter 25 by Fava discusses real case studies involving use of (or failure to use) life cycle information to elucidate burden shifting. The latter chapter could make a perfect introduction to a class on LCA or life cycle thinking with the aim to capture people’s attention and interest to the field.

Overall, this book provides a comprehensive review of the latest advances in the LCA methodology and incorporates perspectives from academics, industry representatives, and LCA practitioners and consultants. I can warmly recommend it for readers with some prior exposure to the LCA methodology.

-Philip Nuss, Yale University, New Haven, CT, USA


Baumann, H. and A.-M. Tillman. 2004. The hitch hiker’s guide to LCA: an orientation in life cycle assessment methodology and application. Lund, Sweden: Studentlitteratur.

Earles, J.M. and A. Halog. 2011. Consequential life cycle assessment: a review. The International Journal of Life Cycle Assessment 16: 445–453. Accessed November 15, 2011.

EC JRC. 2010. General guide for Life Cycle Assessment. Ispra, Italy: European Commission, Joint Research Centre.\. Accessed March 16, 2014.

Guinée, J.B. 2002. Handbook on life cycle assessment: operational guide to the ISO standards. Dordrecht; Boston: Kluwer Academic Publishers.

Hunkeler, D., K. Lichtenvort, and G. Rebitzer. 2008. Environmental Life Cycle Costing. CRC Press, May 29.

U.S. EPA. 2006. Life Cycle Assessment: Principles and Practice. Cincinnati, OH: National Risk Management Research Laboratory, Office of Research and Development, United States Environmental Protection Agency (EPA). Accessed March 16, 2014.


You can find the book reviewed in this article at the following website: