"Sustainable Materials with both eyes open" by Julian Allwood, Johnathan Cullen, et al."

I?was really excited to read this book since it comes from the same stable as the outstanding “Sustainable Energy Without the Hot Air“, by David MacKay, whose review you can read by following the link above.

I am delighted to report that this book did not disappoint! In “Sustainable Materials With Both Eyes Open” (SMWBEO) the reader is treated to an equally accessible, fact-rich and thoroughly credible exploration of whether we can deliver our future material requirements in a carbon-constrained world.

5 materials, 50% reduction

The sustainability of materials is a huge and complex subject. Julian and Johnathan and the team have made this task manageable by considering the five most significant materials in our modern economies: steel, cement, paper, plastic and aluminium, which together account for 5.35 Gt of annual CO2 emissions. This is a staggering 55% of industrial emissions or 12% of the global total of 44 Gt?CO2, including those from agriculture and deforestation. In fact our top two materials, steel and cement, account for the majority of this total, 4.34 Gt of CO2, or 10% of global emissions.

The challenge the book sets itself is to determine if, taking into account very substantial projected growth in demand for these materials, absolute emissions reductions from the use of these materials can be cut by 50% by 2050. I should explain that in 2012, when the book was published, the United Nations Intergovernmental Panel on Climate Change (IPCC) was recommending a 50-85% emissions reduction by 2050 to avoid a temperature increase of 2.0-2.4?°C. Since then the target has tightened to net zero by 2050 in order to avoid 1.5 °C of warming. I will touch on what this means for the books conclusions in due course.

The book starts out by looking in depth at the life-cycle of steel and aluminium, how they are made, where they are used, the proportions which are recycled and so forth. Here the book sets the scene, where we get to understand the global numbers and flows of steel and aluminium. Then, in Part 2, we consider the supply-side of the equation (manufacturing the materials) “with one eye open”. In part 3 we move on to learning of the importance of the demand-side which enables us to consider the problem “with both eyes open”. Here we explore if we can reduce the need to these materials or increase the effectiveness whereby they deliver “services” such as strength, lightness, enclosure and so forth. In part 4 there is a briefer examination of the remaining three materials, cement, plastic, paper before proceeding onto the conclusions in Part 5.

One of the most striking aspects of this book is just how information dense it is. It seems to me that there is a huge amount of work that has gone into supporting the narrative – much of it which seems quite original. This quality stems undoubtedly from the sound industrial and academic credentials of the team who do not only have the pedigree of Cambridge University behind them, but also a ￡1.5m grant from the EPSRC?to investigate carbon reductions in metal industries, called WelMet 2050. ?Although Julian Allwood and Jonathan Cullen are cited as the lead authors, they credit 6 other team members from their Department in Cambridge as contributors in the books’ official citation. No wonder then that we are presented with such an in-depth, fact-based, carefully considered analysis. I particularly like some of the novel graphics which attest to the care and effort put into communication key information clearly and powerfully.

I do urge you explore this book for yourself even if you only read the concluding section. ?I am confident that you will come away with new insights and energy to tackle the necessary changes in the way materials are used and produced.

It is essential at this point to dispel any impression that this attention to detail results in an indigestible meal. Quite the opposite. Great effort has been made to make this book highly readable, with glorious colour graphics and photos bringing the narrative to life throughout, and a style of writing that says “popular science” rather than “paper in Nature”. The device of imaginary conversations between Henry Ford and the Wright Brothers is used to highlight a key tension between standardisation (cheapness) and customisation (lightness and efficiency). Lego Bricks are used to represent stages of manufacturing and we learn that in the 1850’s aluminium was much more expensive than gold.

To my personal taste this popularisation very occasionally detracts from what are essentially very profound messages in the book – for example the little musical extracts that are scattered don’t seem to contribute a great deal. However to dwell on this is to do a disservice because the book truly is a tour de force,?making an intensely complex story with lots of technical content highly accessible. And there is a music CD to accompany the book available on Amazon – so you have to salute the authors for going the whole way with their ideas!

At the end of the day it is the key messages that matter. Once again this book brings home the sheer scale of change we need to undertake in order to achieve significant emissions reductions. These changes have to start on the demand-side?material efficiency?if we are to have any hope at all, and we will require some very powerful policy interventions to overcome the inherent barriers to change. Of all the opportunities to reduce emissions, life extension, more intense use and using less metal by design are shown to be the most effective strategies.

But demand-side changes will also need to be accompanied by supply-side?process efficiency improvements in the way these materials are extracted and produced. Interestingly, Carbon Capture and Storage, often cited as a “silver bullet” for energy-intense industries, is rejected because of the uncertainty about its effectiveness. The authors are to be congratulated for their stance on this - indeed even 12 years on we cannot say with any confidence that carbon capture and storage will be a viable option, although it seems to be the only tool on offer for the decarbonisation of Portland cement.

As in the case of energy generation we discover that the solution is to do all of the above,?at an unprecedented scale and with unparalleled urgency. Welcome to the real world of climate change mitigation.

In the illustrations above the paler blue zone indicated the range of emissions from either steel or aluminium. The purple range indicates the possible process efficiency improvement range - there are limits to this given that every chemical change has a minimum energy requirement. Then the orange range is the possible combination of process efficiency and "materials efficiency", which is the way the materials are used - life extension, more intense use and destings with less metal, for example. Finally, for aluminium the impact of materials efficiency alone is in dark blue which demonstrates that at lower levels of production, implied by materials efficiency, the range of savings from improving the process is relatively low.

These graphs give an unequivocal message to politicians considering emissions reduction targets; if we wish to achieve a 50% cut in emissions, we must not build any new primary production facilities. Instead, globally, we need to reduce primary production by about one-third over the next 40 years.... reduced emissions require reduced primary production.

This is the central principle of a "circular economy", where we keep materials circulating in the "technosphere" for as long as possible, forever ideally. For aluminium we are already achieving 76% which was higher than the values back in 2012, which is good news, but still short of the 90% maximum for both metals that Julian and Johnathan say is technically feasible. For steel about a third of global production uses secondary materials, aka scrap, so there is some way still to go. The reason this is important is that the recycling requires considerably less energy to remake the raw steel or aluminium compared to sourcing it from ores and, in the case of steel carbon-intense blast furnaces can be replaced by electric arc furnaces (aluminium production is already a primarily electric process).

It is the unremitting focus on solutions that makes this an essential title for any resource efficiency or environmental practitioner. I don’t know about you, but I am sick to death with books that just tell me we have a problem! SMWBEO eschews repeating our crisis and gets its head solidly down to working out if we can solve our predicament. As a consequence it is a real breath of fresh air.

Although there is a lack of data in some areas, the authors make clear the basis for the estimation that underpins some of their conclusions, and data sources are generally very well referenced. ?The resulting clinical examination of every source of improvement for the steel and aluminium industries has a high degree of credibility which lends great ?authority to the overall conclusions. Clearly we would need to re-examine the recommendations in the light of more recent data, but for aluminium and steel I believe that the core recommendation to reduce primary production is still valid (but we also need to do everything else).

For cement the key recommendation was to use less - to substitute other materials. For paper global consumption has virtually leveled out since the book was written (demand reduction through people using more "screens" etc) and there remain further opportunities for recycling. Plastics is by far the most complex given the huge variety of products made - recycling is, however, woeful, so there should be opportunities there, and a switch from single use to multi-use plastics will have an impact along with life-extension.

So the book leaves the reader relatively confident that in a world where demand doubles between 2012 and 2050, emissions can be halved (a 75% reduction per unit) for steel and aluminium, but not so clearly for cement, plastic or paper. Now that was a 50% absolute emissions reduction, which we now know is insufficient from a climate change perspective. Should we be disconsolate? No, in short, because in the past decade the world has evolved much more rapidly than Julian and Johnathan anticipated.

A fundamental change in energy outlook

One area where SMWBEO seems to have taken a pessimistic outlook is in the filed of energy generation. In their scenarios they assumed a "medium case" for electricity decarbonisation of only 20% (based in part on David McKay's overly pessimistic predictions about land use needed for solar and wind) and a best case of 30% decarbonisation of generation. Now that seems to be vastly over pessimistic given that, for example, we are looking to netzero generation in the UK sometime between 2030 and 2035. The rate of growth of renewable generation capacity growth is now exponential.

I earnestly hope that the solutions set out in this excellent book are taken seriously and the appropriate policies and incentives are put in place to make them come about. There is an excellent explanation, too, of the changes and choices that we have to make as individuals: whether as employees of the metals industries, as product designers, as buyers or as consumers.

Summary

Although now 12 years old this remains a must read book on materials decarbonisation. It was ambitious at the time, in particular in its effort to reduce the complexity of materials life-cycles and spotlight the kinds of changes that will be needed as we seek to limit global warming. The key points are:

1. We need to think about our demand, and use materials more efficiently. In some areas like plastics and paper we are seeing progress here.
2. On the supply side, we need to reduce extraction from primary sources and instead recycle these materials much more intensely; progress has also been made on this since the book was published but we have some way to go - particularly on plastic.
3. And on the energy inputs, we should electrify these and rapidly build out the renewable generation to support these. Cement remains a challenge and may be the only material where we need to consider carbon capture since the emissions are process-related, not energy related.

This is a must-have title for anyone who is working on sustainability, climate change, life-cycle-assessment or who is just plain interested to know if we can sort our emissions mess out! My own copy is filled with annotations which speaks of the great insight and originality of this work, which has made clear a subject that was relatively unfamiliar to me.

The authors and publishers, UIT, are to be congratulated for making the book available free of charge at?www.withbotheyesopen.com, although the paperback edition is very modestly priced for such a well produced, full-colour title so you may want to buy a physical copy (bear in mind the paper you are using!).

I have also reviewed another UIT title, Climate Change for Football Fans, which is somewhat eclectic and non-academic but nevertheless a great read.

Folks - if you have read this book please leave your own thoughts in the comments below - you may have picked out different aspects which others would find useful!

You may also find my own textbook on energy and resource efficiency helpful - it's free to download :-)

My book was intended as a companion to "Sustainable Energy without the Hot Air" and "Sustainable Materials With Both Eyes Open", hence its title "Energy and Resource Efficiency Without the Tears". For various reasons to do with whether I could release a free pdf version I did not proceed with UIT in the end, but published this independently.

Found this interesting/helpful? This is a link to all the book reviews so far with a brief summary and evaluation.