There are many misunderstandings , when it comes to evaluating resource cycles. As well as in daily practice, as in science. A problem in this is the human perception to focus on things that seem relevant for mankind. For instance the building or a house. Without questioning if that’s also relevant from a physical point of view, or in relation to natural processes. Is the building a relevant item in those evaluations? I will try to show this relation in some examples.
If we want to sustain a building in current practice, we start evaluating that building and we find and define indicators . Even also some physical oriented indicators, which we evaluate in relation to the building. However, implicitly we evaluate the building ( or a car or other useful product) as if that is the highest available value, which can be achieved with energy and resources.
After all, they were raw resources, which have been made useful and functional by man, and in that case have a purpose. And we assume this is also the highest value in a resource cycle.
But what in fact has happened here? We have measured things in terms of value for humans, at least how we think they are valuable. But that’s not by definition how nature looks at things…. For nature, physically, a building or car is not the highest value:they just are , accidentally.
Which we will only see if we zoom out from our limited system analyses, and bring into the picture the whole chain involved in resources. And then we will see that these resources, applied in a building , already went through a few process steps before ending up in a building. In fact they have lost value in that process up till being a building. Or being a car. Or whatever. That is physical value lost, not human appreciated value.
Take for instance iron: at first its quarried with a certain saturation, say 20% in general ores. By processing this, we get iron of 100% purity ( more or less) . At that moment concentration is at its highest, the ‘usability’ as well: the possibilities are endless. Of course, a lot of energy has gone in concentrating the iron, which has in fact decreased another, second, resource in value , to upgrade the iron (or has even disappeared, like depleting oil and gas stocks) . Regarding the material resource itself, the moment it has been concentrated, it has a high physical exergy, which in other words has the highest potential to deliver work, to provide a function. ( imagine if its iron dust particles spread in nature, then the exergy is very low: its hardly possible to deliver work, to make it work for any function)
Next phase is making products from the high concentrated iron. As for instance nails. In this step not only again energy is destroyed, but the iron quality is degraded as well: making nails goes with some materials loss, and since nails are packed in uncountable separate boxes, the iron is diluted. Not that much , but nevertheless. In stead of being a solid iron plate or roll. Think of it this way: it will cost a lot of energy to make again a solid plate from thousands of nails. But still, as long as the nails in boxes are in the storehouse of the producer, the quality loss, exergy loss, is marginal. The real loss in quality starts when the boxes with nails leave the factory, and are spread over the country or even over the world today. . The concentration decreases dramatically. The moment the box is unpacked, and the nails used in a building, a next dilution phase enters: the nails are spread over a building, some lost in the soil, some were bent in the process and end up in the waste. The loss of physical value, of exergy is high. While we value the building as very high, the physical quality of resources is already very low. Which becomes apparent when the building is dismantled and recycled: it will cost a lot of energy to get the nails collected and iron concentrated again in a box, for re-use if you wish. But then, this is still only 1 box of nails, the others spread out over the world.
Nothing wrong with reusing the nails of course, to make human valued useful things, but its wrong to speak of closing the cycle in this stage, of being circular. Its closing a limited cycle, that of a human valued product. Which is different from closing a resource cycle! The last one requires us to follow the resource flow, and not get distracted by what mankind values.
A building or a house, is nothing else as a mess of randomly collected materials and semi products, usually even more complex as the original stock they came from , from concentrated ores, minerals and forests , but now even in such a tiny volume that would never be spotted on the monitor of professional mining exploration projects….
Its even worse for cars for instance. These are composed of hundreds of complex high tech and small products, which once had a high physical value, but are spread over millions of cars. And brought together with hundreds of other de-concentrated parts, from different materials . The car is physically spoken, a disaster, nothing more as a huge complex ore, difficult to mine. On top of that we have spread the cars over the world, and made them mobile, making the dilution maximum. Physically spoken we have done nothing else as to break down a huge concentrated mine with complex ores, into millions of mini mines with complex ores. And hard to catch since mobile….
That we humans can drive in it is fun, but has no value whatsoever. ( even making things worse destroying energy sources).
Unfortunately, , thats not how we assess things. The energy destruction for the upgrading of ores is already seldom included, let alone the following steps of material degradation. Therefore, looking at products and evaluate those,to optimize resource cycles , makes no sense. Even with for instance LCA’s , life cycle analyses of products. To evaluate resources one should assess resource flows, and this can only be done by taking system borders at the level of the earth as a whole , to asses stocks and dilution. *
In fact, you could say there is a double agenda: evaluating resources, but in the light of valuing buildings as human appreciated products. Or the other way around, evaluating buildings assuming its also valid for resources. . Point is, how to define value, and avoid different interpretations, which currently intermingle. The human appreciation for buildings, and the physical value of the resources (and the energy to transform these). Of which the latter is of course highly important , since in the end that should provide the humans with subjectively valued products . But if we look only to the latter, we might end without the first one.
* Take solar panels. These can improve the performance of a functionality, say buildings, a lot. But that is a limited human perception, focused at the building, the human valued form. There is a whole world behind that. First , the embodied energy, the energy used up in the chain to produce the panels, to mine, process and transport the panels . Which improves things ( although hardly applied in practice) but still a limited perception: There are second order effects ( like construction of the factory and machinery) , but even more important : the degradation of resources of which the panels are made is completely out of sight in a buildings evaluation. And that is a approach that only works if the total system is included, in terms of resource stocks in the earth system: the exhaustion of stocks and dilution of mass into the system, or a value for the regeneration of resources.