How can we practice sustainability? Considering the various formulations and failures of sustainability in Part 2, let’s now look at how we can concretely fit better into the earth system.
Neoclassical economic theory assumes that energy and matter (goods) flow in a system with unlimited resources (inputs) and with an unlimited capacity to process waste. This is not because the supporters of this theory think that the world is infinitely there for our use, but because neoclassical theory assumes that technologies will always find better substitutes for sources and between waste treatments, so that economic growth can continue without environmental degradation so long as we sufficiently encourage research, development and the diffusion of better methods and technologies.
As a technology developer, I am inclined to believe this; as a physicist, I know it is impossible because it ignores dispersion. Dispersion is an important concept for understanding sustainability and was explained in Part 1. If you haven’t read the first part, here is an example. The undesirable species (“weeds”) in agriculture mentioned in Part 1 usually mate sexually, so their offspring are genetically diverse. Any herbicide acts on them like a strong “natural” selection, where some individuals happen to survive herbicides for many possible reasons: they may happen to have genes that block the herbicide, or bind a molecule to the herbicide so that it becomes ineffective, or alter the plant internally so that the herbicide cannot find a target, and so on. For example [1], each female pigweed produces hundreds of thousands of seeds each year, and there are billions of pigweed individuals on farmland, even though herbicide cocktails containing 10 different toxins are used today. And now guess: How many employees do you need in the research facilities of the herbicide companies to develop new herbicides faster than all surviving pigweed plants diversify and multiply?
Inventing new herbicides will not keep weeds out of our fields unless we also destroy the entire environment surrounding our fields (which is already happening and contributing to a devastating loss of biodiversity). So technological substitutes cannot always be a path to sustainability. We also need to change our mindset and our systems [2], for example by adopting dispersed agriculture or a closed form of agriculture (see below).
Personally, I think along the following lines. Sustainability has to do with how we build structures. With our brains, we can tap into huge flows of energy and of matter in a way that no animals can. This enables us to build our large but highly ordered structures, and we can easily and quickly destroy complex structures around us, for example with chainsaws. Physics says that building structures requires energy and inevitably leads to dispersion that can be damaging. This may look grim at first glance, but physics leaves us free to decide what kinds of structures we build and how we cause the dispersion. In physics terminology, nature only imposes boundary conditions on us, but gives us many degrees of inner freedom within those boundaries.
Based on these physical limits, I think that three minimal criteria for sustainability emerge:
1. minimal criterion: in many (not all) parts of the world, we can build on structures without expanding them, and even shrink them to put less pressure on the surrounding nature.
12,000 years ago, when the last ice age ended, humans were already so widespread and numerous that they shaped already about three quarters of the global land surface through hunting, species propagation, burning practices, and so on [3], [4a]:
But this has mostly (not always [4b]) been gentle. Nevertheless, the idea that wild areas have never been affected by humans and that sustainability means that we have to give up land completely is not scientifically supported [3]. The main problem is that we now use half of the land too intensively and are expanding this area more and more. Drylands in particular are increasingly used mainly for livestock as well as grain production (a third of which is grown for livestock as well). Also, forests are being more degraded in their complexity than their area shrinkage suggests in this graph. However, in many parts of the world, we can reduce agricultural land and still feed ourselves, for example by eating less meat in rich and middle-income countries. Practicing more greenhouse [5], [6] and vertical farming [7] is not trivial to do environmentally friendly [8], [9] but they allow us to work mostly in a closed loop. We can additionally use the current trend of urbanisation [4] to make cities more sustainable [10].
The next criterion is easily explained with coal-fired power plants as an example. They do not only disperse part of their energy into heat and discharge it into cooling towers or rivers, but they also disperse CO2. Solar cells only disperse heat. That is why they are mounted as panels on roofs and not integrated into roof tiles, so that the heat can be easily dissipated. This example shows that:
2. minimal criterion: we can minimise the dispersion of materials and thus have mostly heat energy in our dispersive flows.
In a previous blog article, I explained that scarce elements such as gallium, yttrium and cerium are mined to make LED light bulbs. But these elements are incorporated into each light bulb in such tiny quantities that they can hardly be recycled. This means that the scarce materials enter the dispersive flow. In this way, their economic value and availability does not accumulate over generations of light bulbs, but approaches zero, so more mining is needed to maintain a continuous flow from mining to dispersion. The switch from classic bulbs to white LED bulbs has made lighting more energy efficient, reducing the dispersal of heat, but has increased the dispersal of scarce materials. This is not a sustainable path for an industry.
We will see in the next blog article that renewable energies have hardly any materials in their dispersion streams. Of course, this is only a first and necessary step towards a sustainable future because that alone is not enough to be sustainable. It doesn’t make much difference whether the chainsaw runs on petrol or on a battery charged by green electricity. Building sustainable structures poses greater challenges:
3. minimal criterion: by adapting our technology, systems and our behaviour, we can close the loop on most materials, including food, so that we do not force the biosphere into an unfavourable state.
Sounds similar to our romantic notions of nature in Part 1 of this blog: that nature recycles, optimally adapts form to function, and uses only the energy and resources it needs….
What seemed like a romantic idea of nature in Part 1 is a projection of how we should behave ourselves. We know deep down and intuitively what we can do to be sustainable.
This makes me confident that we are in the process of avoiding the worst consequences. We don’t have to learn and do radically new things, we already know it deep inside us. However, we do need to avoid letting our other desires suppress what we know how to do. What are these other desires?
Some quick tools
To conclude this blog, here are some more tools that you can apply in your own field. You may ask yourself the following three questions:
1. What time and space scales do you consider when you think about sustainability?
Your company may already call its raw materials sustainable if they come from a forest or a lake while the product is sold for a few years (narrow time and space scale). As a policy maker, you may think about many generations and the global level, but this may be too abstract to save this very forest or lake [11].
2. How is your focus on sustainability divided between the four areas of materials, ecology, economy and social?
Here [12], [13] are examples for these four areas:
Should you include another area to have more impact? Or focus on fewer areas to be sufficiently concrete?
3. On which of these hierarchies is your thinking about sustainability based?
Again, some examples [12]:
Should you add another hierarchy to be more effective? Or change to another hierarchy?
And finally:
To what extent is your sustainability goal merely focused on a short-term survival of your activities, or also on the long-term preservation of the biosphere?
To finish off, I would like to point out an important distinction: You can rarely make a product or a company significantly more sustainable simply by improving efficiency (like by using less material or energy) or by switching to different ingredients (like recyclable materials); they help, but you usually have to change at least the design, if not a significant part of your value chain. It is not even certain whether consumerism can be made sustainable without changing the economic framework. The important difference between efficiency improvements and sustainability becomes clearer if you read the blog “Basic categories of greenhouse gas mitigation” here. Or, in short, you can imagine that any efficiency improvement made today will be overtaken by economic growth one day in the future when you find yourself back in yesterday.
I think sustainability is an overused term that companies tend to use to sell their products. The actual improvements are often not so great that they are worth mentioning in product descriptions and company statements. For example, a product rarely “protects the environment”, it always has a footprint. And I hope that after reading these three blog articles you will find many more statements nonsensical.
On the other hand, I sometimes have the impression that environmentalists tend to use the term sustainability as a mere keyword without making a concrete demand. If they make sustainability concrete, the demands carry more weight and are more likely to be implemented.
It takes imagination and effort to make things sustainable.
More so if you do it alone. We are in a complex web of supply chains, but it is precisely this web that enables and requires each actor to contribute. This is how you too are able and vital to contribute. Your circle of influence is a good starting point, regardless how small or big it is, and please do not import excuses from beyond.
Climate protection measures must be carried out in a sustainable manner, otherwise we jump out of the frying pan into the fire. The next blog will be about the sustainability of renewable energies. Are they really sustainable? And what if they are not?
Regards,
Pietro
Acknowledgements
The diagrams “Focus in sustainability” and “Sustainability hierarchy” were created using the software Xmind with some manual adjustments to make them more compact. The remaining graphs, as usual, with the freeware Veusz.
References
[1] H. C. Brown, “Attack of the superweeds,” New York Times, 21-Aug-2021. https://ift.tt/3k2QcV4
[2] A shift of mindset may lead us to incorporate planetary boundaries into our economy and to become aware of what concretely happens when we cross these boundaries. Young people hold up banners like “There is no planet B”. You may find this message worn out, but it addresses an important change of mind.
[3] E. C. Ellis et al., “People have shaped most of terrestrial nature for at least 12,000 years,” Proceedings of the National Academy of Sciences 118 (2021). https://doi.org/10.1073/pnas.2023483118
[4a] M. Roser et al., “Our World in Data,” Oxford Martin School, University of Oxford, UK, with the Global Change Data Lab. https://ourworldindata.org ; https://ourworldindata.org/land-use
[4b] C. Sandom et al., “Global late Quaternary megafauna extinctions linked to humans, not climate change,” Proceedings of the Royal Society B: Biological Sciences 281, 20133254 (2014). http://dx.doi.org/10.1098/rspb.2013.3254
[5] A. J. Castro et al., “Six Collective Challenges for Sustainability of Almería Greenhouse Horticulture,” International Journal of Environmental Research and Public Health 16 (2019). https://doi.org/10.3390/ijerph16214097
[6] R. T. van der Velde, W. Voogt, and P. W. Pickhardt, “Kasza: design of a closed water system for the greenhouse horticulture,” Water Science and Technology 58 (2008). https://doi.org/10.2166/wst.2008.697
[7] S. Asseng et al., “Wheat yield potential in controlled-environment vertical farms,” Proceedings of the National Academy of Sciences 117 (2020). https://doi.org/10.1073/pnas.2002655117
[8] Y. Li et al., “Organic management practices enhance soil food web biomass and complexity under greenhouse conditions,” Applied Soil Ecology 167 (2021). https://doi.org/10.1016/j.apsoil.2021.104010
[9] C. van der Salm, W. Voogt, E. Beerling, J. van Ruijven, and E. van Os, “Minimising emissions to water bodies from NW European greenhouses; with focus on Dutch vegetable cultivation,” Agricultural Water Management 242 (2020). https://doi.org/10.1016/j.agwat.2020.106398
[10] J. Chang et al., “Modern cities modelled as ‘super‐cells’ rather than multicellular organisms: Implications for industry, goods and services,” BioEssays 43 (2021). https://doi.org/10.1002/bies.202100041
[11] B. J. Brown, M. E. Hanson, D. M. Liverman, and R. W. Merideth, “Global sustainability: Toward definition,” Environmental Management 11 (1987). https://doi.org/10.1007/BF01867238
[12] P. Glavič and R. Lukman, “Review of sustainability terms and their definitions,” Journal of Cleaner Production 15 (2007). https://doi.org/10.1016/j.jclepro.2006.12.006
[13] M. U. Ben-Eli, “Sustainability: definition and five core principles, a systems perspective,” Sustainability Science 13 (2018). https://doi.org/10.1007/s11625-018-0564-3 This quote is taken from p. 1340 but I omitted “[…such that the population develops] to express its full potential” because I find this too arbitrary. I also disagree for example on his first principle on p. 1341: “Contain entropy”. This does not make physically sense, as explained in the previous blog Part 1.
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