 Our second panel, again, in no intentional way, is focused more on, as we call them technologists, for lack of a better term, but more over to trying to build this narrative arc and think about how wonderfully actually the talks we just heard actually set up many technical questions that I myself as a pigeon hold engineer there often. I'm surprised at how much I learned about technical aspects of thinking about concrete construction, even it's very material science in terms of ecology and life. And how concrete itself is, you know, a dynamic thing was one of the main components of the last conference and I think we're going to continue that. In this panel, particularly thinking about concrete and energy there was one question in the Q&A that we really fit into the last one but I think sets us up maybe in this one and that one thing to realize about concrete that we didn't touch on at all in the last is that it is directly acting as a thermodynamic medium in our built environment as well. And that relationship is one of both it's making. So that relates to what we just referred to in the forests not being burned to fire the kilns for concrete, in a strange way now we're rethinking because we're now firing our kilns with fossil fuels and so is there a way that we should be returning to biomass or does that make sense and those kinds of questions on the larger scale. As I referred to earlier life cycles of materials or whether that is really the right framework to be bringing in to rethink concrete's use and whether or not there's just a different thing that we should thinking about in terms of after concrete. I'm just thinking broadly about all those interrelationships that concrete has in the built environment, both the fact that as you pour it, it heats up and one point of reference to that question particularly about how heat is a byproduct of curing concrete is that Brandon Clifford who spoke at the last conference actually has a project cooking with concrete where he pours food inside concrete to cook it using that heat. So there are all kinds of polemics out there with concrete and he's the one that's more common in my world and maybe in some of my collaborators and some of our participants in this panel is also how it relates to the energy infrastructure of buildings and heating and how it is a massive substance and what might be other massive substances that we can use to think about concrete and energy or broadly. So we have a great slate of speakers. First from McGill University, architect and amazing author and thinker and good friend and then followed, following him. Lola been alone from Columbia will bring us some context on alternative materials we can think about from concrete, followed by David Benjamin also from Columbia. So I've worked with mostly on wood actually here at Princeton on a building that he designed here and he'll bring in some ideas around embodied energy and how architects can design with these concepts. Felix Heisel from Cornell, thinking of the circular economy and materials and how those come together. And then finally Dan Stanger as Lucia mentioned earlier today. I'm an engineering at Columbia, who is an expert and renowned scientist and energy housed in a department that origin originates itself in materials so that will be a fun place to land so up first we have keel welcome friend. Thank you so much for joining us. I'm very excited to kick off the debate around materials and their life cycles and concrete. Wonderful. Thank you for inviting me for us Lucia. It's great as always this is a great conversation. Happy to be a part of it. So today I'm going to speak about the fallacy of misplaced concreteness which is according to Whitehead Albert North Whitehead. Sorry. The fallacy is the error the fallacy misplaced concreteness is the error of mistaking the abstract for the concrete. One of his students summarized the fallacy misplaced concreteness by observing that at least misleads us into thinking that we have all of reality when we have instead only part of it. And consequently we inquire and live with inadequate abstractions and insufficient concreteness. An entity that seems concrete or otherwise well defined like a molecule or a building is actually often an abstraction and incomplete description. At the core of our misplaced concreteness and architecture is an even more basic ontological problem that Whitehead identifies as the problem of simple location location. To quote him to say that a bit of matter has a simple location means that in expressing its spatial temple relations it is adequate to state that it is where it is in a different finite region of space and throughout a definite finite duration of time. Apart from any essentials reference to the relations of that bit of matter to other regions of space or to other durations of time. I shall argue that among the primary elements of nature as apprehended in our immediate experience. There is no element whatsoever which possesses this character of simple location. In short, because it's so directly implicated that in building and architecture. That last phase is worth restating that there is no element which possesses this character of simple location. Here for instance the chair that you are sitting in it cannot be fully described by its present property as simply located under you, rather it is present location and state is only one of many unfolding states. One episode in its full spatial temporal relations on this planet. These relations would include the biogeophysical basis the chairs source matter to its extraction to its the industrial and labor processes that transformed it into its present form, as well as its future states in which it will be moved around your abode altered broken and repaired, and perhaps discarded at some point disintegrating back into the environment from which it emerged. No doubt one could provide a rich and intricate description of the chair and its present state under you, but less a less abstract description of the chair will only emerge from a much more extended explication of all of its spatial temple relations. If we merely describe the chair as there underneath you, then our description is characteristically limited. And what is true is something is putatively simple as a chair is most certainly the case for something as dress really complex and process intensive as contemporary building, building to be sure is not simply located. Despite many received traditions of design and description building spatial temporary temple relations cannot be situated in a definite finite region of space through a definite finite duration of time. The better grass matter like concrete much less more complex material organizations like buildings we need to move beyond architecture's problem of simple location that stunts its reasoning and imagination about what architecture is and does as a terrestrial entity to The main matter is to become much more literal and concrete about the manifold states processes world systems that are presently absent from discussions of material and building, of course, excluding the present company. From a terrestrial perspective, though, the corporal and corporeal character of buildings ecology and world systems is just as concrete as the corporeal building itself. The corporeal world systems of a building shape the concreteness of reality, not just a certain architectural artifacts on specific sites, maybe in Manhattan, but the other environmental and social conditions of collective life around this planet. These terrestrial systems are not external to the practice of architecture far from people places and processes cannot be abstracted from this process of building. Building is possible without them and to include them from our description of building is engraved is a grave error. One case of the misplaced the fallacy of misplaced concreteness pertinent to this symposium focused on the dynamics of dynamics of materials is the example of life cycle self assessment or LCA. LCA is putatively a way to assess the environmental aspects associated with the product over its quote unquote life cycle. It vainly describes vainly strives to answer quick queries such as what environment impact does one object have over the other variants of LCA. Each of which suffer the vicissitudes of the human centric metaphor of its nomenclature include cradle to gate cradle to grave and cradle to cradle. In each variant the accounting of the dynamics and cycles of the product in question begins with the cradle, or its moment of extraction by humans and then on to processing transportation emissions and so forth. The arithmetic of LCA accounting begins with extraction. And this assignment of a product building products cradle as the moment of at the moment of extraction poses the core problem of LCA through its system boundary definition. It includes the biogeophysical work of the planet and all the important terrestrial relations and processes that precede extraction. In part in both methodological and philosophical terms the system boundary definition of LCA treats the planet as an infinite reserve, as a stock of free sort resources awaiting human restriction. As Bill Bram and his colleagues have noted, the notion that raw material materials for building construction are plentiful and can be extracted at will from the first geobiosphere is alarming and entirely inaccurate. In other words, LCA is teleological. It is a mode of description made in terms of the human processes and purposes intended for those resources, rather than the terrestrial causes by which matter and energy arise on this planet. Note that behavior and tendencies of living systems. Okay, so in this regard LCA is a receiver theory of value, as opposed to a donor based theory of value which I think is the important distinction that we'll probably return to. As a method of description LCA does not refer to the total terrestrial life of an object or a process or a material, as it's nomenclature inherently suggests but rather only to the life of that product. This is the use value, most often in the techno managerial context of a neoliberal economy. It certainly does not provide despite its misnomer, a description of the life and the full spatial temporal relations of a terrestrial entity. In short, in much of the way that sustainable design is neither sustainable nor theory of design life cycle assessment unnecessarily limits how we reason and imagine the life cycles and assessment of things on this planet. To illustrate the fallacy of misplaced concreteness of LCA in action, consider the dynamics of timber architecture. LCA is used pervasively in the research and design of timber buildings, especially in terms of mass timber carbon cycles. The LCA of carbon and timber building components hazards calculations regarding how much carbon is assumed to be locked in the cellular solid structure of timber material at its moment of extraction. The LCA of carbon and timber building components. Sorry, at this at this moment of extraction and when the timbers cut and removed from the forest. This extraction is the timbers cradle stage and paradoxically reflects the moment in which the timbers cut away from a living system of forest. Thus the cradle stage of timber at once marks the death of the living tree in the forest, and the birth of that timbers life as a commodity. LCA tracks its postmortem cycles emissions and uses based on this calculation of how the now dead timber is processed the assumed carbon storage of a mass timber component is then extrapolated to a total amount of carbon stored in the material in the building itself. The misplaced concreteness of LCA building calculations accounts is is an inextricably counted independent of the biogeophysical dynamics of the forest. The method abstracts quite crudely myriad living system processes from its calculation. So this fallacy vessel here is within the following observation that the carbon commonly understood to be locked into timber does not in the ecological sense of carbon cycles come from trees. It comes from forest and the biology of physical work of the planet, the carbon captured in timber building components is rather a displacement of these other forest processes. The carbon stored in timber building components is an outcome of carbon cycles and pooling in these larger systems. The ecology and carbon dynamics of the forest are as real as the timber building component itself, and moreover not only make the timber building products possible but is the only way for properly accounting the actual carbon dynamics of the timber building component. If the forest itself is a source of carbon emissions as it is the case in Canada, then any material extracted from that source from that forest cannot magically and suddenly become a carbon sink in our urban built environments. This is all the more true when the timber building component has been extracted transported process installed maintained and eventually demolished through a plethora of carbon emission intensive processes. In other words, just because you have a debit card does not mean that you have any money in your account. Construing the carbon stored as a material property as LCA does is a primary example of Whitehead's problem of simple location. These LCA calculations simply locate the carbon in the timber building product. This is an error that undermines the primary motivations and purposes of addressing the carbon cycles of building in the first place. So carbon is not a material property, but rather a property of the dynamics of much larger systems. No carbon cycle whatsoever plot possesses the property of simple location in other words. The terrestrial living processes have been excluded. In the, in the name of life cycles assessment is particularly ironic. In this case of the fallacy of misplaced concreteness. The simple location of carbon and timber LCAs, as to quote, Whitehead student misleads us into thinking we have all of reality when instead we only have part of it. So accordingly, these misplaced claims about carbon become concretized in our discourse, you know, in Scotland scientific literature as well as in popular kind of boosterism for mass timber construction. So it's not merely a base scientific error that I'm discussing but it's something that quickly propagates to the discourse and through the practice and through the political ecology of timber. And as Gregory Bates and stated that there is an ecology of bad ideas just as there is an ecology of weeds, and it is characteristic of the system that basic error propagates itself. By contrast our ability to properly reason and imagine the carbon dynamics of mass timber hinges on our ability to expand our understanding of timber to include for us, in this case, or the actually living systems that do the consequential work of photosynthesis, as well as myriad other chemical material energetic hydrological and other forms of planetary work. In this regard the complexity of ecology rather than the reductive techno managerial use value accounting of LCA better serves as a basis for our understanding of how humans interact with the thin surface of this planet. Much of the carbon sequestered by forest is locked into elements other than trees forest carbon is pooled below ground and soil and roots and loose litter on the ground and above ground and dead trees to name but a few of these pools and cycles. In this regard, again, that any carbon that we imagine involved in buildings is just a displacement of these types of terrestrial processes above ground woody harvested woody biomass is but one and not necessarily the most important or largest pool of carbon in most forests, and to not grasp this, the dynamics of this carbon pooling, and thus not to construe to timber building as a new type of above ground carbon pool itself really limits our description of what a timber building is and what its carbon cycles might be. So, I'll wrap up by simply just making a case that we need a much broader system boundary, we need an ecological view of these dynamics as we describe materials such as timber or concrete to ourselves and architecture. And just as I guess as a closer. I do believe deeply that our best pedagogy for this is systems ecology, specifically in the form of power to Odum's absolutely breathtaking, not only scientific understanding of this but the kind of political ecology that was inherent to all of his scholarship. So I'll leave it there and pass it on to my next colleague. Thank you very much. Fantastic. Thank you. I'm struck by as Lola I think is next high Lola. As she sets up I'm struck by the fact that we're if we're elaborating an alternate theory of material is not something that's just here and there. I'm just keeping track of the things that are the there that elsewhere so far you pointed to the pool, the carbon pool but earlier this morning we also heard about the factory, the other there. In Rod's case the cement factory is often forgotten when talked about when we talk about the ubiquity of concrete it's often forgotten that the fact that cement has to be produced somewhere offers opportunities for monopoly and that's another place that one could point to another let's say absence. And then of course the stock that a T I was pointing us to as a place that is also absent from something that can be controlled in your case you're talking about the pool which is a different gesture you're pointing something larger but like Lola, unless somebody has any specific questions for keel. And now I don't see any in that. Okay, so then we will move on to Lola. Go right ahead. Sure. Thank you. I'm really did I did to be here today. Such a great discussion since the beginning of the morning. Thank you, Forrest and Lucia for having me and thank you for all the other participants and my slide that I would hope to challenge the notion of what concrete is, and what technologies could be applied for earth and by based alternatives to concrete. But let's first start at the beginning right the evolution of conventional building materials have started with, you know the adoption and improvement of materials that were mined and curated from nature nearby right. And that has been allowing a great increase in efficiency pace amount of construction. So that's the good thing so we essentially started with curating these spaces in nature. And specifically in natural caves like this one near my hometown in Israel. That were the first buildings made of thermal mass right so the large heat capacity here of the cave walls regulated our space temperatures with really low fluctuations that were less than one degree Celsius between day and night. So that thermal mass absorbs thermal energy and gives a thermal energy back in a way that regulates the surrounding temperatures. And with this notion in mind I really wanted to go back to what concrete how concrete is defined and how it was developed as a solidified form of matter right imitating this cave like dwelling in a more predictable and even shapeable manner. So, the word concrete comes from Latin in a sense of matter that grows together from the interaction between its components to form a mass resembling stone on hardening. So how do we create those artificial case what is the basic formula for this artificial rock and we all hopefully kind of know the answer. It is aggregate plus the binder. For the Romans the binder was lime and volcanic ash from Potoli and Italy. And there are new forms of concrete like hemp creep that breathe things aggregates and use strong fibers of hemp as aggregate. And our modern Portland cement concrete uses Portland cement, which is the most energy intense binder of all concrete so far. And today we will see what earth grid is about. We'll discuss that an earth grid uses clay as a natural binder it is raw clay it is not heated at all. So, how do we use these perspectives of what concrete is to inform a greater intelligence in sourcing materials for concrete. How do we use new materials, how do you use new supply chain mechanisms. How do you use critical thinking. What's nice is that although each of these building materials were initially taken from earth, each of these materials are earth materials, fiberglass comes from sand, still from ore bearing rock and concrete from limestone. The thing is that they had to go through these complex processes to become the building products we know of, and kind of increasing the amounts of processing transportation between harvesting something at source and placing it into our buildings. But when I say earth or natural and living building materials, the definition I refer to is materials that are readily available, minimally processed. So we shrink down that supply chain that are non toxic also those materials and community engaging. And sometimes I like to call them and farm to building materials. Specifically earth based materials would be made of fibers that provide the tensile strength and those fibers would be weaved throughout the matrix, send or aggregate as a compressive strength provider like we know for conventional concrete and clay as the binder. The various combinations of these constituent materials would provide a diversity of techniques and styles, and just to illustrate the diversity of the broad range of, for instance, styles and also thermal possibilities here. And Cobb on the left is a monolithic sculptural technique around Earth, which uses formwork kind of to mimic the process of sedimentary rock creation, and then light straw clay that is an insulated infill turned within a structural frame. Let me close this window because there's so much noise outside. So, of course, earth materials are very sustainable they offer a waste free life cycle, but they're also very healthy for occupants and for builders, they are non toxic and they act as a PRM so passive materials for VOCs as you can see here in the chart. And what's a little different from the cured concrete or Portland cement concrete is that Earth creates have high hydric capacity, which makes them act as a flywheel of indoor relative humidity. So they provide kind of an optimal relative humidity level for human health. Well, it seems totally out of our focus. Earth create materials still shelter three billion people around the world. So it's a vernacular material in Europe as it is in Africa. And therefore we need to find ways to kind of enhance this material that has been proven itself for over a millennia, rather than replace it. Because earth materials are very community engaging and they can be dirt cheap, because we can use soil that is excavated for the foundation. Now, I want to make an interesting discussion here about parallel to food. So just as you are what you eat rings true and have generated an immense industry of healthy foods. Through the spaces we live and work in affect our lives and health, of course, now more than ever we feel that, and the trend of claiming for healthier and low carbon spaces would only increase. So our responsibility as researchers as engineers designers and building professionals is to ensure that these natural living materials follow responsible growing practice just as permaculture and sustainable farming for food, but for building materials. So, but before that happens before the industry grows, earth materials currently are still non commodified, which makes them very slow, as opposed to concrete that cures earth concretes dry. But the question is, can we slow down for a moment and ask, can slowness be a good thing, which is a funny question for me because I'm a very fast person, but looking at the slow food movement, for instance, which emerged as a response to industrialized fast food production. What we, what they have recognized is that there's need to preserve regional styles of food to limit loss of material diversity and focus on human nourishment, rather than the crop yield. Very similarly in architectural design, prevailing construction trends are drawing us technologists towards high speed industrialized construction that is increasingly automated, capitalized, globalized and standardized right. So in a way that the global, the global goals of the slow food movements are as applicable to the production of space and shelter, as they are to food so kind of the slow construction movement, let's call it like that so slowness can be useful as a framework for developing the only alternative means of construction in a world that has fit physical resources and exponentially increasing computational capacity, but also as a more engaging and enjoyable self capacity for building and maintaining our own structures. We use digital technologies to inform this notion, take a long human centric view towards construction technology. So in this project, for instance, we demonstrated ground earth designs that extend and expand traditional food and digital and analog fabrication, while repurposing local soils. We use utility functions related to environmental adaptation, self shading and self cooling of the mass assemblies to develop these new surface tectonics for round earth which is often very limited to linear surfaces. So it's a great fun working with material because working with earth. I love concrete and working with concrete is can be a little nasty with ends, which is why I'm more so low love earthquakes. And the best example for earthen structures can be found by designers builders like in these two houses. In our left staircase. I just love working with builders I think builders are truly knowledgeable about how best to use materials, they can really see beyond the design, how the material case. They have this intimate relationships with the material that we as engineers and designers should adopt and learn from. In this workshop we produce this staircase that you can see here on the left. And there are tons of workshops so just to show like a simple search here. Endless workshops of Cobb round earth light stocklay and this is because earth based concretes are very easy to learn and self build. It's very community engaging. It starts with safety problems and poor construction practices and durability issues. And that leads to a perceptual problem with these materials being low tech, small scale and not viable for mainstream construction, which is notion that, of course we need to change and referring back to Sophia's notion on the life of the material, the material and leaving aspects of aging. One interesting thing about earthquakes is that life is part of the construction process. So for instance, builders of earthquakes know in vernacular practices that they use the phenomena of sprouting earth walls to indicate when the wall dries. When the wall is sprout twill. That is when the wall is dry and ready for the finished layer. So in one of our projects we started with this perception survey in global context, asking, what people really think about earth and buildings what is the problem. Why isn't it mainstream. And what was astonishing to see is the strength of the perceptual barrier where 25% of experts of earth buildings around the world indicated that there is a perceptual gap in the form of cultural prejudice and social perception. How do we overcome this negative perception. We first use appropriate design and testing protocols and you can see here on the right that appropriate design of earth buildings really means a good pair of boots and a nice umbrella so high footing and a deep proof hang to reduce the danger of an erosion and this photo was taken in New Mexico you can see the snow footing here that kind of stay away from the wall and this is a raw clay plaster 20 years of age and it's amazing. There is a really perceived limited building height on earth buildings but actually earthen infills and clay based interior finishes can be applied at any scale right it. And those building technology solutions are developing in places like Germany and New Zealand, where great earthen building codes exist. There's a technical gap that is required. I won't dive into this too much today but it had us develop the life cycle inventory for earth based materials, and this is just an illustrator illustration of the embodied phase results. I'm not going to go into the operational phase results but, of course, that was important to enumerate the enhanced performance of earth based materials over conventionally insulated materials. We investigated the thermal survivability in earth buildings, projecting on predicted future climate scenarios. And we were astonished to discover that the heat and moisture flux mechanism of earth assemblies really increased the interaction with the surrounding humidity, which in turns create an intrinsic self cooling capacity, and that was really interesting. And without survivability eventually it's really about the hands on working with these materials to gain self sufficiency. In this project, you can see me applying a final coat of cob plaster to a shower that is made from adobe bricks. And this is the final outcome, finished with a layer of tadillac which is burnished lime plaster, and a tile mosaic. All those interests of my current mission has been to really teach earthquakes to architects and engineers. Having students really ask themselves, what does this material want to be and how do you change your design based on the material behavior, how do you utilize locally available mass materials for with the community. You combine material science and technologies without losing this, you know vernacular hands on enjoyment. So these are the next generation of what I like to call concrete, earth based bacterial based self healing, right and they all require this additional thermal perceptual policy environmental and design innovations, and educational avenues to be implemented in this kind of instruction. And I think that is it for now for me. So thank you. Thanks so much, Lola. Fantastic. Sure. So talking about slowness I hope I wasn't too fast. No. I'll raise you your speed and raise your mind. I have a quick question for you. It's not quite a clarification is just a comment while David sets up, which is continuing this conversation we're having this morning about the comparative aspect of materials that both epistemologically the idea of a material is very strange things because a catalog of unlike things steel and concrete and would are supposed to be very unlike each other but they have this in common that they're thought of as a material. And then the discussion we were having about material new materials being announced as being in comparison to others to older ones reinforce concrete better than an unreinforced concrete, reinforce concrete more suitable than stone etc. In your case it seems to me, earthquake invites comparison, you brand it as a concrete, but it's a comparison that it can't possibly uphold. I mean it upholds some aspects of it, but in terms of the incredible triumphant performance of concrete and harmful performance of concrete over the last hundred year let's say earthquake is not trying to compete with that so I'm just thinking about asking you like, and maybe maybe you can answer later but do you think of that designation as a material as strategic are you doing it. And that's what people will understand, people want a material they want a thing called the material or more on the contrary is it is it truly help systemically because you're going to eventually take over modes of making specific infrastructure you know specific ways technologically that it makes sense to call it. So it's kind of a question. Sure. I'll answer in short and then, along with the question I can add up. There's, I have a colleague who told me about a producer David Easton in California, who developed compressed earth round earth bricks that have compressive strength. It's a conventional concrete which is an absolutely amazing technological investment. And as he shared kind of the product with potential clients. He often heard, can you put just a little cement in it. There is that comparison or not possible impossible comparison right to you know the concrete that lasts so long. And that is one thought but another thought is really you're asking maybe why am I kind of trying to advance or a kind of, and it is a romantic view on a material I agree that there is a romantic view here, because I really love working with the material. So it's also something I would also personal that I'm trying to kind of infect others and finance or two yeah yes. You can easily stabilize earth and materials with a little bit of lime. And that doesn't, it doesn't give you the same increase in compressive strength that you're concerned about but I'm stabilized earth and materials even for highway construction have been used in this country for decades. And there's a big body of literature on this from the Florida Department of Highways I believe, and also the National Lime Association. And we're now talking other types of stabilizing and reinforcing agents for earth that are could be even better than fine. But there are so many avenues to advance this material. Apparently even sticky rice mortar, according to the question in the chat so we'll, but we'll come back to hopefully the broader discussion of the. Some of these alternative components, which takes us to David Benjamin thinking broadly about how systems feedback on themselves and the, the, some of these interesting and alternative nuances of biological systems that might be leveraged, kind of outside of maybe just the direct replacement of a material. I don't think that that is not extremely important but I think I'm excited to hear David give us some perspective on some of the amazing concepts and ideas, but I think this picture represents very well. Thanks to David. Great. Thanks for us. Thanks to Chia, and thanks to all the other speakers for the exciting ideas and presentations of the event. So instead of kind of the idea of after concrete or we could maybe also say beyond concrete. I'd like to take up for us to Chia on the provocation to use concrete as a kind of trigger to think more broadly about materials, energy and research in architecture, you know, as we've already heard from Keel and Lola in this panel. I should say that I really love the premise of the event and the paper, in part because it's such a powerful illustration of the idea that buildings are really dynamic systems rather than static objects buildings are always changing buildings are not inert, but rather they are perpetually exchanging with their environments in a wide range of ways. So in one sense, buildings could be kind of like the forest as shown in this visualization of the invisible exchange of carbon shown in red, and hydrogen shown in blue this kind of transformation of energy and materials, sometimes at a kind of microscopic level. And so for me the question of how do we theorize materials and energy is not only linked to the question of how do we create technology for materials and energy. Importantly to the question of how do we design with materials and energy. And this question in turn is connected and intertwined with the question, how do we draw materials and energy. I'll go back to drawing in a few minutes but I first want to describe some of my recent thinking about several different models of research for materials, energy and technology and architecture that I think are relevant to this discussion. So here I'm thinking mainly about models for technology and the practice domain, rather than the history and theory domain, but clearly some of these ideas might be expanded. I'm going to say, you know, I'm sure that all of these research models are familiar to everyone so I'm not going to reveal anything new with the models but I think it's helpful to, to list the models and consider them when we think about how to do some of the new and urgent work on concrete on materials in general and on energy. So just briefly that research model one could be funded science and research, for example, University Research funded by the National Science Foundation or something like RPE. This is related to concrete and other building materials obviously. And in fact, I'm actually right now working with RPE on helping to define a new track about carbon negative building materials. And building materials are a huge part of that, including a huge discussion about concrete. Research model two we could call this industry and entrepreneurship. One example is BioMason startup company that's developed an alternative to concrete that's made through bacteria fusing aggregate into bricks with no heating and almost no carbon emissions. So, this kind of idea of industrializing new research or research through industry. Research model three exhibitions and pavilions, you know, for example, the Venice Biennale coming up soon and other exhibitions they offer, you know, a different model for engaging and experimenting with materials, sometimes concrete, sometimes concrete alternatives. Also experimenting with more broadly with energy and, of course, many other issues. And research model for building commissions, you know, almost too obvious to mention but, you know, for example, we see as he'll mentioned every day we're seeing the examples of timber structures that are often positioned as an alternative to concrete structures. And here the building commission can sometimes be considered as a research project in itself. So part of my point here is to say that often work and research takes place primarily within a single model. There are clearly some pathways between models, including from model one to model two, sometimes from model three to model four. Yet I think there could be more links between them and more paths through all of them. The models are not mutually exclusive. The models could be considered as a fluid system with feedback loops. And just as we are learning to think holistically and system wide in combining actions to address climate change. We might also think holistically and system wide in combining models to address materials and energy combining these different research models. So the more I want to propose a fifth category or model this is a little less developed. It's beyond the models we typically consider which is drawing or more specifically drawing the invisible. So this is really the point of some of my thoughts for this talk which is to describe this model in a little bit more detail, and tell you some different ways that, along with others that I've been thinking about it and working on it. So the model of drawing or drawing the invisible includes drawing processes like drawing energy and physical resources, drawing labor, drawing time. And these are topics that we've been working on at Columbia GSAP for the past few years through the embodied energy and design project, including some related exhibitions. Some related courses, a symposium a few years ago at the school, and the subsequent book that came out of that symposium. And in this project of starting to think about drawing embodied energy and drawing the invisible and in a way drawing materials and energy more generally. So we looked at some amazing precedents of drawing invisible but essential forces. We looked at how who builds your architecture, the kind of advocacy group is has been working with drawn labor and architecture. And we looked at some more recent and experimental ideas like drawing clouds of microbes in the city. This is some work by Kevin Slavin and the playful systems lab. So when we turn to embodied energy, we started our analysis, including our work on the embodied energy and concrete through trying to draw data visualizations. So a visualization like this shows us graphically that buildings account for a third or more of global waste energy consumption and carbon emissions. And this kind of drawing shows us that embodied energy defined as the energy required to extract produce transport and assemble materials into buildings, embodied energy has been increasing over time. Here's a data visualization or a drawing showing the breakdown of embodied energy by materials so looking at embodied energy in their concrete or aluminum or glass and comparing those. Here's a visualization showing the breakdown of embodied energy by building component such as structure envelope finishes. Yet another one showing the breakdown by process, things like extraction transportation and manufacturing. So we're drawing comparing specific buildings for example, in a recent case study, a new timber tower involved slightly less embodied energy, but about 75% less embodied carbon, then our comparable 50 year old concrete and steel tower. This kind of visualization translates some of the numbers of embodied energy into quantities that are more intuitive so if we look at the amount of embodied energy in the new relatively new Shanghai tower we could convert that to 34 million cars on the road for a day, or 481 million pounds of coal burns so this kind of making it more tangible to some of our everyday life. The point that I'm trying to make here is that we quickly realized that data alone was not enough and drawing the data, drawing the quantitative was not enough. We also needed to understand some of the qualitative and relational aspects of embodied energy. So we moved to drawing what we call material stories, the narrative of a material like concrete or wood or steel. The narrative and the story from extraction to factory production to transportation to construction. So here's the material story of concrete trying to draw within the same drawing within the same frame, the entire story, kind of over time and over space of a single material like concrete. You know, here's an example of doing the same thing, drawing the material story for a different material, which is steel. And yet another one drawing the material story with wood as an architectural material. So we used this kind of framework to draw questions as much as we were using it to draw conclusions. So we drew a range of material formations and sites beyond what we typically consider to be the building beyond what we typically consider as part of what the architect would design. So for example here is the site of a limestone quarry. It's a cement silo with corresponding kind of markups in red. The building foundation and the concrete structure. So several different sites involved in the material story of concrete. Similarly, you know if we think about steel here's the site of iron ore extraction for steel. The site of a steel former, a container ship, a steel yard, and a steel structure. And likewise, I think you see where I'm going here for wood here is a forest sawmill, a lumber yard, and the balloon frame structure of the building. So these drawings these material stories reveal something important about our buildings their research model beyond the quantitative, but also different than the historical even though they're narrative, like history. And they're not just analytical or not just meant to be analytical tools but they can also be used as tools for design active working tools for the design of buildings. So here, the framework of embodied energy is not just an underexplored aspect of architecture, but it's also a lens through which we might see all kinds of invisible, but essential features of architecture such as embody water and body carbon or So finally, I just want to mention that these methods and processes of drawing have informed my own small architectural practice of the living. They were part of some of our early work with a new material of mycelium brick that in some ways could be understood as an alternative to concrete. It's a structural brick that has almost no embodied energy, no carbon emissions and no waste, and a brick that is compostable so that at the end of its useful life, it can return to the earth and into a productive ecosystem. So this kind of project intersects with model three exhibitions and pavilions. And here are drawings are really experiments with drawing time, drawing decay and drawing the transformation of matter and energy. And similarly this drawing process was also part of some of our more recent projects in our firm, including the design of the embodied computation lab at Princeton forest mentioned this building we work closely with forest and others on this. It's a building that was made in large part through wood. This project intersects with model four that I was mentioning building commissions. And it involves things like drawing sourcing drawing fabrication drawing installation and drawing objects so here we designed the transformation of materials over time. Starting with a repurposed material, which were New York City scaffolding boards shown here kind of being taken down from a construction site, then handling the physical materials. And then using a kind of algorithmic process of machine learning and a new form of drawing to reveal some of the forgotten aspects of the material to visualize time in a way to see how each board each scaffolding board comes from a specific place a specific resource a specific tree that grew in specific conditions and formed in specific ways. And then, in the physical object of the building, and this kind of drawing that we're making up that object. The facade registers the story of the material it's a kind of embodiment of the material story from resource extraction to initial use as scaffolding to computational analysis and identification of unique features to a certain kind of selective application to eventual reuse as a building facade. And maybe more fundamentally this kind of drawing and this kind of including the drawing and design process, allowed us to develop a new perspective on buildings as really just a temporary formulation of materials energy and labor connected to other processes before and after the life of the building. So finally, in a kind of feedback loop. These methods and processes are now part of a new line of experimentation that we've been doing with what we're sometimes calling multi species architecture and this is back to model three exhibitions. And here we're thinking about the invisible microbial world. The microbes are everywhere in the built environment they're in the air on our bodies and even in our architecture and in our concrete as we had mentioned earlier. And just as we're increasingly aware of the bacteria in our own bodies and the way of gut microbiome contributes to our individual health. And you might also start paying attention to the bacteria in our cities, and the way an urban microbiome contributes to our collective health. It turns out that a diverse community of microbes tends to create a healthier environment, and some materials can be better than others that promote promoting this kind of diverse microbial community that we want. Maybe better than others at creating what we could call probiotic architecture. So there are some experiments with bio receptive concrete that are working on these kind of ideas. And there are also other bio receptive materials that can be designed and drawn so in this project for storefront for art and architecture we experimented with wood as one example of a bio receptive material. And here in this project in this experiment, we actually swabbed the material. Then sequence the DNA that was in the architecture on the architecture in the material, and we visualize the output through a strange type of drawing shown here, and tried to derive insights about the types of microbes on different kinds of materials, and in different neighborhoods of the city. So this was an experiment in drawing the invisible layer of microbes that are part of our materials and our energy ecosystems. And finally, here's another experiment along those lines that we're currently doing for the Venice architecture BNLA which opens in two weeks where we're experimenting with yet another bio receptive material and another method of drawing. So really to conclude the ideas that were expanding from concrete to other materials, and also expanding from materials designed to change and materials that are designed to age to also experimenting with materials that are designed to exchange and materials that are designed to nourish. So I suppose my concluding hypothesis is that we might discover new understandings of materials and energy, and also new forms of action in the face of things like climate change through new forms of drawing. Thank you. Thanks Dan. Fantastic I look forward to engaging in conversation with Sophia. I was thinking why you're sharing the drawings with Keele in terms of how the drawings might inform this idea of life cycle, not really being often not including a lot of the things that you actually are able to draw representationally. So, so thanks for that. I think there was a couple questions. Oh, no, just good job in the comments. I think we're have another great transition here to Felix unless the chair you had any question for David specifically. Okay, yeah, I'm looking for the discussion everything I think is, you know, coming together almost too well. So I'm extremely excited also to get to introduce my friend Felix Heisel who survived the Singapore heat with me over a few years of research. My part being probably failing to cool things well enough for him but in his part developing an awesome intellectual framework to rethink materials in the circular circular economy. I'm continuing that Cornell in the circular construction lab, and I'm really excited to bring him in to give us some of the perspective on how this context of materials is actually the one where we can mine and rethink some of these sources and sites which I think will build wonderfully on the story of our mining of scaffolding boards and going much further than that. So thanks Felix I'm very excited to have you. Thank you. Thank you, Lucian first for inviting me. Thank you all the other panelists before me it's an incredibly interesting conversation and I'm looking forward to the panel afterwards. And I wanted to talk today about the circular economy or specifically construction in the framework of a circular economy with a little bit of focus on on questions of design with projects that came out of our lab and in my office. So this is his teamwork, just as a disclaimer and the one that gets talk about it but of course there's a big team of students and colleagues behind this. Since we're talking about time so much, I want to start quickly with a much larger time scale. I'm back 800,000 years. The planet has really been controlled for the last 800,000 years by what is called the Milankovitch cycles and I'm sure I'm not telling most of you anything new here but I think it is important to set this up to show the importance of that paradigm shift that we're really working towards. And so, within this, then looking at the influence of humans in the last 70 years, and how the influence of humans suddenly became more important in in how the, how the planet behaves is is incredibly thought and talking and scary right and it really doesn't matter which of these charts we look at they're all essentially similar they're exponential they start somewhere in the 1950s. And this is because this is then the reason why we talk about the Anthropocene with a starting point around that time. So if we look at one of these charts a bit more specifically then it's the extraction of global resources. The magenta here being what is allocated for the build environment and sorry that these are German but the left side really talks about the total extraction. On the left side, I think it's important to also look at the per capita extraction because you could say well this is all due just to the fact that we have an increase in population. But in fact also the per capita consumption of resources, especially in the build environment has been increasing since again the 1950s, dramatically. And this linear system that we're that we're working or building and at the moment, the build environment really stands for 50% of research extraction 50% of solid rice production, and arguably, arguably even 50% of carbon dioxide emissions. This year saying 40 but the nearest numbers are even higher. And so, if we look at this, this kind of scary numbers, of course the question that we have to ask ourselves is what is the, why do we do this right what is the service time of all of these materials before they from the beginning of that linear use till the end. And we're, as architects we sometimes think that we built for eternity. Brunelleschi formulated this already in 1380 or something like that 1390. We built the the Florence dome, but of course the reality is that this time is much more somewhere around 50 in China. We're now talking about a service time of buildings of 25 years. So we're looking at this in a much more specific angle, which element of which building actually has what kind of service time, and how can we then compare the service time with the lifetime of buildings right, which are something completely is, is I guess the big question to ask and so one of the solutions that we're talking about that that can do the shift is really talk about a circular economy we maximize kind of the the usability in several cycles of materials. So we separate the technical from the biological cycles and I'll go into that in a bit more detail later, and of course drive the system with regenerative sources because only then we actually have a kind of circular economy. And if you try to define the circular economy I guess one of the important words in that definition is the word designs or circular economy is a restorative and regenerative system by design right and this is for me a call to action for for all of us. So to go to the beginning of the cycle and really think about how can we do things differently how can we design waste out of the system and keep all products at their highest utility in value throughout their their service and their lifetimes. And so this is what we're doing at the at the circular construction lab we're looking at the one side of course at the big question what do we do with everything that is already out there. So I guess in in the question that Lucia asked for it earlier what is the other there right for me the other there is the built environment as it stands kind of the existing buildings out there and how can we include those are bring those back into into the system. And then the other question looking forward how do we design differently from now on that we don't have this problem that we talk about material management and kind of an asset management where we take things out of one building move them to the next without having any any losses in that step. And the third part that I'm quickly going to address today in this talk is the question what do we need to make this possible or kind of tools or software or thinking stands behind that. And so the first of these also often referred to as urban mining is is all of these are basically not new ideas. The first time urban mining was mentioned in in this kind of going back in in literature is by by Jane Jacobs in her 1969 publication the economy of cities where she speaks about kind of prophetically about the the city of the future being the largest most prosperous and richest mind that can be easily most easy worked on and is inexhaustible right because it's kind of a self-fulfilling prophecy that keeps it keeps fulfilling its its source it keeps filling its source and reactivating the source and to a certain extent we we've reached that point. These are studies from from Japan where we see this now specifically talking about metals that the amount of metals that is already in the in the built environment exceeds the current known underground reserve of these metals. The problem in this way of looking at it is that of course none of these components were designed for reuse or very little of those right this is the more common way of of demolition. So the end of life of buildings. And it is incredibly hard to to reactivate any of these sources if this is the common technology right. And so the question that we need to ask is what are new technologies what are new ways of activating the the resource that we have available. Even if it hasn't been planned for this kind of scenario. And one one little project that we've done in 2019 is called the Mayovet pavilion. This basically goes to David's model for the pavilion building as a research where we built this pavilion only out of resources that were already in the build environment. Everything that you see here had a second a third or four of life already in before it arrived in this building. And we categorized it in in four categories. All the ground is made out of mineral demolition waste and all the furniture is made of recycled household plastics. The framework the structural components are out of reused steel emphasis on reuse. That's the much more difficult part since steel usually is already to 90% 80% recycled of course, and then the roof and the facade is made out of recycled glass. And when you zoom in closer you see that this of course brings with it the kind of history of that material here of course as as part of a pavilion structure a bit over the focus is on that aspect of course but especially this glass texture for example where you see these old in this case wine bottles that create this wonderful texture and that bring in these these shards of class. I think bring adds a new dimension to our material palette that is extremely important in the way we design future buildings. And the second important element about this pavilion was that we actually took out all the steel from a decommissioned coal fire plan. Power plan that in Germany's are all being shut down right now because of the change to renewable energy sources and and so these immense minds are being blown up with a lot of very little care to the material and we managed to take out some of these steel structure steel elements but we had no idea what the steel is we didn't know what type of steel how long it's been there what happened to it during the lifetime and so bringing that into the German building code required significant amount of testing batch testing a tensile testing not testing chemical composition, vulnerability etc etc to then prove in the end that this is standard structural steel and and can be easily used in in this pavilion. And so the need for documentation and I get to that in a little while is is another really important aspect of that. Now that shift towards a circular economy. And then of course coming back to the design. The, the length of the elements that we took out of this pavilion of course then the defined for us. The structural tree like assembly of of this pavilion and something that would probably look different if we would have gotten that steel from a normal, normal supply chain. A second very quick example is then directed towards how do we design differently looking at the future this is the urban mining recycling unit that we built in Switzerland. What we're looking at is just as this unit in the middle that has this copper frame around it. And here we went into that building with a brief to to construct something that is 100% recyclable so all connections, everything that went in there. Has to be able to go back into their material loops at the end of the service time of that building, which then resulted in a fleet in these three cycles of the spotter fly diagram here on the right side a kind of biological metabolism that is much bigger than the material itself right so that a timber can turn into a mycelium based component or or grass or you know something else that isn't part of the built environment. On the left side you have this very direct reuse and recycling of technical components as the example of the glass shows, but the biggest question of course is how do you do this in a in a way that in a way that that really brings out the quality of that of that space right we want to live in a kind of aesthetically pleasing environment, but still talks about the history of the materials and about the way this moving forward this can be disassembled. And so this is a modular modular unit build out of seven completely prefabricated elements that were then only assembled on site with a couple screws and can of course the same way be disassembled taken out of the building site again, and then all the material salvaged and returned into their specific cycle so the design for disassembly here is the main component already in the development of the architecture. And one example that describes this best are the bathrooms how do you build something that is waterproof right shower without the use of any adhesive without the use of any silicone no glues anything kind of no chemical adhesives right and so this is all just dry gaskets just compression. One screw added you just loosen that take it apart again. And so you have the clean and sorted and mono material cycles again at the end of that of that building. And again, the kind of beauty of the aesthetic of these of these materials. This particular economy also talks a lot about new business models right the moment we develop materials on products that are fully recyclable of course we can use them differently we can lease them we can run them. We can bring an extended bridge the liability so that this example here for for example is a carpet that we only lease for eight years and then return to the producer, the producer because of that can then anticipate resource for their production in eight years they know this is coming back. So they can plan with that and reduce their, their dependency on volatile resource markets. And then just as mentioned before the importance of documentation. And this is a kind of set of material passports that we developed for this building to know exactly which product is where in which amounts. When will it be available again and of course the question is how do you do that for the urban line so at the lab we're right now developing new tools with using augmented reality for example to to ease the deconstruction and to estimate material amounts and really always thinking about how can we can we close this gap between supply and demand, moving forward in a kind of new design understanding where the resource for the design really is what is already available in our cities and that of course then also relates to the question to an urban question right because we have to do this not on one building at time but really match between buildings across the city. And so that's my last slide here trying to show that on a little study for Ithaca in upstate New York will be now estimated all the compared to the operational and the embodied carbon emissions for for each building but of course we're relying on a very detailed model that we that we semi automatically constructed from GS data and LiDAR data etc. To estimate you know what is in which building and how can we match these buildings moving forward. Thank you. That looks fantastic. I think another great set of examples. And context, I think to bring into the picture in the debate about exactly where you close the edges of your loop I guess this is the thing I think then every presentation. I've seen something where we're going to come to the end and be like what about the crane and the picture or what about the. And I think that's, I think I'm glad we had keel this sort of lead us off to think in that way but I think it helps us to recognize just how important it is to be doing this hard work of thinking about the broader system and scope so thanks so much again for those really I think one thing that hasn't been represented considering we're in architecture school and maybe I'm not the person that should say this, but there is a role for aesthetics making things last a certain amount of time and have importance. So I don't think we should try not to forget that. But with that architectural reference. Now I'm going to shift to my good engineering friend, Dan Stangard. He was my, in some ways, mentor and how to be an open minded engineering thinker as he sat behind the wall right over there next to me for several years. And he's now though the co director of the Columbia electrochemical energy center, which speaks to his expertise directly as a thinker around how we store energy in materials. The first project we actually worked together on was a pretty wild idea about storing energy and concrete, which is more about asking questions that may be a little bit crazy and seeing where they go. He's now a professor in the Department of Earth and Environmental Engineering and I just want to point out because we realize this was relevant when we're on meeting this morning. But that's actually the department that used to be for mining at Columbia and I find it very appropriate that now we have Dan here to talk about energy, which kind of speaks to how we've transferred from an age of material resources to one of energy resources and I think that's kind of where we want to arrive at the end of our narrative art for the conference. So thanks Dan for agreeing to join us and maybe not the typical kind of conference you would be a part of. But I know, having been a part of many talks with you that it's going to be fantastic. So take it away my friend. Thank you Forest and Lucia for the really kind invitation and feel very outclassed here it's real honor to be part of this super interesting conversation. As an academic engineer and partially a practicing engineer, I'm trying to avoid the puns here but I'm going to be a bit more concrete on concrete and talk about something that Forest motivated and a lot of energy goes into concrete but can we get energy from concrete. And so, can concrete produce energy even in a secondary fashion are my slides showing up okay here. This is the right looking game. Okay, thank you. So, so can can concrete produce energy and perhaps a better question and I'll motivate this why in a few slides is should should concrete produce energy. We've heard many times over the course of the day that concrete is dynamic. It's dynamic on time scales that that we typically don't think about in in batteries or at least in energy storage energy production. We think about cycling over these months weeks and years but there's significant structural change within a battery over that cycle. And the structural change of concrete, we hope is over a long period of time if we're going to advertise its cost to the earth and cost to the atmosphere. The only thing that produces energy is at some way out of equilibrium with its environment and meaning that that it reacts with its environment or reacts within its system to reach some sort of equilibrium. After which it can no longer provide energy, so we can recharge the system we can do this thermally we can do this electrically, we can do this chemically so that that is once again out of equilibrium and that energy can be exploited once again. But the question is, is can what we expect concrete to do do this is there a positive couple is there a positive synergy here. And so when the energy is spent the system is in this equilibrium. So, can we have our concrete within a system which is taking up a lot of mass and can it be overloaded. And so this this isn't allegorical the components of concrete are metals that have been stripped of their ability to do what we expect metals to do. They break rather than bend, they no longer conduct electricity, they're no longer reactive surfaces in the same way the terminology that that's been used here I'm going to use term oxidation to cover it all the oxidation through carbonation. Typically, unless we engineer it very precisely in a very particular way, generally means that the materials are no longer reactive. Functionally, this is a benefit of concrete because even though it does age even though it slowly loses the properties that we wanted to have initially that process is slow enough to be blunt to make someone some money for a certain amount of time and to have a building do what it's supposed to do for a certain amount of time. And the question is, is, can what a battery needs to do which is react very quickly in this time scale somehow positively couple to this. This change of metals is inevitable. I think about my PhD advisor who was a metallurgist and his partner, who was the chief ceramicist for NASA and they would have these very cute arguments that the metal just wants to be an oxide or an oxide is is just an impure metal and this was this made for a very fun Christmas dinners. But the, the idea is that is that concrete is a wonderful engineering material because it, at least in the beginning of its life interacts positive in a positive manner with its surrounding environment and then a long term question that that clear white who I believe many of you know, thinks about is, is how can the functional life of a concrete be extended through carbonation rather than deteriorated so this is an interesting long term question but it's this inevitability that makes the battery worthwhile and it rather that makes a concrete behaves so so well in my estimation and so this is a beauty of the engineered structure. If it's not done well, oxidation is just rushed right so what I'll say is this chaotic corrosion and chaotic oxidation creates brittle structures. So, so when a steel structure is not properly protected and when steel structure is left to a human environment corrodes and passivates in such a way that that leads to a lack of structural integrity, but a well big concrete does does the opposite. So, the question is, is, 10 this energy that goes into baking concrete be taken out or partially taken out. So this building structure can both provide support while also providing energy. And so, let me talk about batteries a little bit what a battery is supposed to do. A battery needs to cycle in some way shape or form between metallic and oxide ideals and you can picture this as becoming concrete and becoming steel and and you may think I'm using the term concrete loosely here but when I show you an SCM micrograph of the guts of a double a battery in a few slides, you'll notice that the morphology and the particle matrix structure really does invoke concrete. And when a battery dies, when a battery is no longer cyclable and we can no longer put energy into it nor get energy out. The process by which the battery dies is very similar to the process by which concrete is is cured it's this oxidation process that successfully passivates interfaces from further oxidation. Sometimes this can last 1000 oxidized interface. Thousands of times, and sometimes this this this only lasts once the terminology I'm using for concrete here just because I want to make sure what I'm about to say makes a bit more sense. There is some type of a particle sand crushed on gravel in a binder, and it's the chemical reaction and thermal activation of this binder that chores it in an air or air analogous atmosphere. And the goal is to prevent surface activity. So, so, so, so for batteries. This is this is a bad thing for for for for for structures is typically good thing this is a bad thing for batteries because we need these interfaces to be active. So if we look at this micrograph, and we see that where IP and OP are pointing the edges of those particles within a battery are continuously trading electrons and ions to store and release energy. And as they do so, the mechanical properties change in a significant way, both at a NATO scale and at a microscopic and macroscopic state. If you don't think about a battery as a reversible mechanical device or device that has significant mechanical consequences as it operates. Let me share this video with you. That that will invoke this structure on the slide after I spent, I want to say, at least a decade of my life trying to get a double a battery to be rechargeable to take the batteries that we buy and use once in our remote controls and flashlights. You see what happens when you put, try to put electricity back into it. Because the chemical reactions on paper are reversible but it's the structure within, and the nature of the chemical reaction the physical consequences of chemical reaction that determine a large part whether or not we can, we can reverse these structures. I would tell my friends this and one of my friends sent me a video that highlighted what you're going to see in column 100 and column zero and what my group did was to run the interstitials and so what we did here was take a double a battery. And we discharged it 10% and then we ran this experiment where we simply dropped the battery. And when we dropped this battery, and it was new, and it wasn't discharged, it wouldn't bounce. And when the battery, when we discharge the battery beyond taking 20% of its capacity out. It was to bounce a little bit and then and then the bouncing levels often, and this was unexpected. When I saw the initial bounce video because I had been studying the structure of these batteries for for 10 years. It didn't surprise me too much for what I'm about to show you but the fact that it changed in this manner was, was quite eye opening and actually helped us explain a failure mechanism and the failure to actually get directly analogous to, to concrete. That is to say that if I had a battery, and I only took 20% of the energy out of this battery put that 20% back in. I could run that cycle, thousands of times with this particular texture. But if I took 50% of the energy out and tried to put it back in it simply wouldn't accept the energy. And here's why the structure of the battery particularly the zinc anode. This is what the structure looks like when it is fresh when we first open the package, and as built notice that there's a significant amount of porosity. These particles are loosely connected, even in the preparation of this micrograph we oxidized it and so you see that this structure looks more akin to the concrete that that we would expect to be a structural material. And this does not this would be a poorly cured material more akin to gravel or something like this. In a discharged state. The zinc is fully oxidized, and we see that that there is very little porosity and the interfaces are almost all gone. And what happens as we discharge this structure is that the loosely packed zinc oxidizes and the potassium hydroxide which is a binder for for modern carbon free concrete reacts with oxygen that's made available through the counter electrode. And we get this poor feeling reaction that prevents the zinc from reacting anymore. So we're forming a kind of concrete within the battery and the formation of this concrete is what prevents the battery from from ever working again. So, I was trying to come up with ways of reversing this, and I was getting to know forest and Claire at the time and, and, and the question was, is, is, if this is really analogous to concrete and this carbonation as I was learning is a problem for concrete so it's that the carbonation then going to carbonation is a challenge for the structure of concretes. Can we positively couple these things put electricity into these structures to reverse the carbonation were partially reverse the oxidation of rebar and get to a point where the system can continually take and accept electrons, even in a partially oxidized state but not taking it all the way. So if you can imagine, having a wall constantly attached to the grid, constantly accepting and giving small amounts of electricity breathing electricity if you will, to maintain its physical structure. And so we call this project overloaded structures and the idea is, is, is simply this taking two forms of iron and earth abundant materials one is is iron oxyhydroxide. The other is iron mixed with manganese dioxide and manganese dioxide is a material that is co extracted with iron so it actually makes a better use of iron tailings. And the question was is, is, can we design this so that the rebar would be the active electrode within the system, and the porous concrete or the porous rocks, rock like structures around the rebar would be flooded with solvent, because concrete as I understand it likes to be very dry or very wet but not similar in between. And by operating this we can constantly refresh the structure. So things got pretty weird because the carbonates still formed, and we then looked into how we can cycle carbonates and carbonates are really the deadest of the dead. As these carbonates form, they're very hard to electrochemically reverse and when we talk about how to deal with the carbon dioxide in the atmosphere, it's of the same problem if we can simply run an electrochemical reaction to split carbon from the oxygen by leaving electrodes that we would, it turns out that carbon dioxide is just exceptionally stable stuff and this is, this is one of the main triggers of one of the main reasons why reverse climate changes is going to be so challenging. And what's, what's, what's interesting is that carbonates can even be toxic and so rat poison is a specific kind of carbonate we said, huh, that the structure that we're creating here is, is sort of similar to rat poison. So if rat poison is toxic, this indicates that it might be chemically available and therefore electrochemically available. So, we wrote a paper on on electrochemically cycling a version of rat poison that that actually worked okay but but it's still eventually so eventually by cycling the rat poison it stopped being rat poison, it stopped being toxic, which also meant it stopped being chemically active. So, so the problem had layers of complexity that that that even after studying it for a decade I didn't realize until we tried to make this this concrete battery. So, so this was required context because I had been implicitly trying to reverse these concrete like structures that formed in batteries for years and years and years. I had been doing so because the way batteries have been designed for ever since the first modern electrochemical cells in were developed in 1800 by Daniel and Volta. They were designed to fail in this way and so I'm going to invoke two key terms and electrochemistry corrosion and pacification. And we, when we design a battery, we implicitly choose passivation over corrosion, because the energy that's available in the battery remains accessible for longer for a one use operation if the battery fails via passivation, rather than failing via corrosion. The way to think about this is the the silly Duracell ads where they say the battery is going to last for 10 years. They designed the battery to slowly passivate over this 10 years rather than quickly corroding, because you're not intended or that battery is not designed to take the electrons back. And so by designing a pacification failure mechanism, the self discharge of the system is much slower. And we've been doing this for 200 years so as I was trying to reverse the concretization of these batteries I realized that we were trying to do this. We've been fighting this natural and almost inevitable phenomenon for 200 years without making too much headway towards it. And the way the concrete forms is exceptionally complicated within the battery just like it is outside the battery and this is why we need neutrons and x-rays to study it even today. But this got me thinking about the implicit design of the battery and the fact that it was designed to passivate because when the battery was first invented in 1800 there was no electric grid. There was no way to readily recharge it and so we wanted the electrons to always be available from the system. Now, in 2015 when I started this work, 2021 for sure, when we think about batteries that back up the grid, they're always connected to the grid. They almost always will have a source of electrons every day if we think about supplying enough stored electricity to compensate for the stochastic nature of wind and solar energy. The battery will always be accepted electrons but the priority is to not accept electrons but give electrons. So we said let's redesign the battery from scratch and make it so that rechargeability is number one with a bullet. So we designed a battery to avoid passivation at all costs, and we look for chemical systems that can do this, and we stumbled upon bromine, which is nasty stuff in its own way but wonderful stuff in another way. So something you can think about as liquid oxygen. It is more oxidizing than oxygen but in its natural state it's a liquid rather than a gas, and that gives it key physical properties that that that enhance corrosion rates rather than enhancing pacification rates. So, so by making a battery specifically to avoid concretization what we saw was that we can make a battery that could be cycled forever while doing what a battery was not supposed to do 200 years ago. And so this is a cross section of this battery that we designed. And it is charging and discharging it's constantly short circuiting. It's constantly corroding but it is always available to accept and give electrons and its behavior can be quite predictable and so this is a very new way of making batteries. But we're developing the the transport models and an electrochemical understanding of this sort of as we speak I've got a big project in my lab on doing this and, and again the entire point of the system was to avoid forming concrete because by avoid forming a type of concrete within the battery again, it would last forever. So, I guess, after the study what I realized is that is that many ways of concrete battery is an oxymoron because the very aspects of concrete that that we know and love. In terms of its structural performance, inherently make it difficult to reverse the energetics of it. Now maybe this is possible, but but it's quite challenging. But by taking this understanding of what concrete is and how concrete forms and designing a battery to avoid this at all costs, we invented a new way of storing energy that may hopefully have a better. I'm going to avoid the word lifecycle analysis, because I agree with that critique 100%, but may have a better advertising schedule. So thanks so much again for for the really kind invitation. It's been a lot of fun. Well, thank you, Dan. I like that you felt the need to define for us what concrete, how you are using the word concrete as though we were somehow police that. It's so great to have this is a capping to the conversation on essentially energy like the, all the panel we've heard direct the conversation to energy and this is completely blown apart the object of architecture. The line between what is a resource and what is, let's say what is passivating what is being passivated towards, if I can use that language. You're here twice. Yes, I'm here, because I feel like we were debating whether we needed a break. But I would just point that you can go outside if you have a phone, but this is also to give something very relevant to Dan's talk, which is that we do make buildings that passivate and do all kinds of interesting things and the Ann Linger Center Building is one of them. And just for small entertainment value and to go outside but also to show you that chemistry and buildings is real. This is the concrete of the building. And you can see, there's all of that calcium carbonate that our building is naturally releasing as water drains through this stairwell, somewhat improperly which you can just see a drop fall there. So again, this is just to show maybe a real life example of the ways in which concrete is in fact alive. So this exact same material that you'll see in stalactites form in caves though it happens much faster. In the building when water flows through concrete and changes the sort of chemical dynamics of what are happening. So, you know, if you've ever been to a cave they tell you don't touch them because they take thousands of years to grow but these take about a few months to grow. And that just gives a sense of how concrete is real. We lost forest. Classic, but thank you for. Okay, so thank you to our panelists. Yes, yes, thank you. Fantastic. Just a quick sort of because we're, we might suddenly be joined by people expecting the keynote and also to tell our keynote speaker own we will take 15 minutes for for a good Q&A discussion I think that's what it takes to at least have a good back and forth. And then, as we said, because we're rolling and some and our keynote speaker is very late in the evening, I think we will go straight to a for the keynote 120. But in the meantime, I wanted to start off the conversation by just noting that it's been very interesting in this panel to hear that beauty has returned. The beauty was, you know, David and Felix, I was holding my questions for you, because on the one hand I find that your desire to visualize energy is clearly what's making you both render materials visible again so you both redrawing materials and you're representing them as materials you know this is wood. This is how it's understood in the, in the construction process or this is a recycled or reused material and they have to be made visible because indeed, those materials don't are not often featured as, you know, heroic protagonists of architectural culture. So it's already work to visualize objects that, you know, or maybe down the chain. On the other hand, in terms of energy, I did notice a significant stepping away compared to the first panel of the human, you know the original human motor their original, you know person who experiences and exerts energy. So you can comment a little bit on what pressure you feel to either visualize or not, or talk about or not because of course your visualizations show us very much that you know exactly what labor it will take to build something what movements with labor in the abstract sense of who will build it but or how much it will cost let's say, but also the specific technical gestures that have to be done. So I'm wondering if in your visualizations between material and energy. So what are the pressures and what are the opportunities for, you know, the human motor, let's say that is also experiencing energy and producing it and delivering it. And then I'll have a separate question for Dan, not about the humans. So you want to go first sir. And I'll jump in. So I mean, I think the first part is easy, or it's not easy but easier. The question about beauty I think for me is important. If we talk about sustainability. The love for something is probably the most driving the quickest driving force to make it last longer. So if you if you enjoy something you start taking care of it. And that maybe brings us also to the kind of influence of the human in all of this right I mean we can talk about numbers all we want if if we want to live in a circular economy then then that moment where I pick something up and throw it away. Is it or not right is an essential moment in the question do we close that loop or not. And so, bringing it back to that beauty if if I if I want to take care of it. It is more likely that I treat it in a more circular way. And so I think that is something that we as architects should be talking about I mean we were designers. Bringing the design aspect back into that conversation in terms of, you know, prolonging the use of material not necessarily from the use of the service time but along the use of that material. I think it's an important aspect. Felix, your presentation. It seemed to me had a kind of secondary point, which actually was extremely strong in that you made a great argument for preserving existing buildings, and the road to that. And that at least is improving materials and methods that would be used for repair and maintenance. So I would just urge the participants and attendees and so on to take a look at what's going on now as a joint process between the American Concrete Institute and the International Concrete Repair Institute. And so it all has been released in the last two years or so two or three years, and also a larger project that the Getty Conservation Institute began in 2012 called conserving modern architecture initiative, which has now focused on among things, but has focused very much on concrete structures and the Getty trying to partner with people in the UK and in France who are working on concrete repair as a means to hold on to these buildings rather than demolish and try to recycle materials into new structures. That's a good point. I agree. I mean, the most sustainable building if you want to use that term is the one that's already there in terms of materials, not necessarily in many other questions. Yeah, we had a great person from the Getty right this year, or that was working on the last conference too, for reference. Any question I guess and how do you translate that to practice. Maybe I'll push the envelope a little on the pavilion project David like the doing exhibitions and pavilions and how much, how much resistance there is also to Lola, and it's really hard to change standards. So this relates to both obstacles in terms of standards but then obstacles in terms of not building what people are used to things looking like I guess, how much have you found ways around or address some of those challenges. Yeah, I mean I'll just add that I think the idea of drawing human is is really important so that's a great question. And for me, I think we've been looking for ways to do things like draw the human in the same frame as we're drawing the object and the flows of energy. So, you know, those material stories as preliminary as they are, are one way to do that. I mean they, they have the human figure doing the labor at the same time they have the objects moving around the matter being, you know, transformed. And although this is maybe a loose connection. But as we've started to try to draw something like the microbial world, you know this invisible layer that's all around us. It's really challenged us in a good way about how to draw, you know, where's the boundary between the human and the non human. So everyone knows these statistics like there are more microbial cells in the human body than than than human cells in the human body. So there's already this exchange going on how do we draw that how do we draw that interface with the materials which also have this layer of microbes on top and inside. I think that's that's I guess where I was trying to go that like the drawings rather than be a place where we would. So I almost want to challenge the beauty thing. The drawings are not a place where we would go to like make beautiful drawings or use a drawing to make a beautiful that the drawings are a place where we can try to understand in a new way what all these exchanges are what the what's happening with the materials and the energy and the humans and the social dynamics can we can we use the drawing to do that rather than make, you know some glossy one off representation. It strikes me that what's in a way you were sort of drawing what Sophia was describing this morning, with microbial environments, you know, if concrete is going to be understood as ubiquitous and we might as well consider it an environment for life of all scales. And the and the challenge would be to be able to draw into it human experience that is not exclusively related to the person who make the concrete or the person who forget that concrete is there but to challenge that. Okay, if this is the concrete that one habituates to because materials are so pervasive that they help us habituate to our world. And so what is the proper visualization of that in a way that both challenges the notion of habituation to a material and at the same time invites the kind of pleasure that Lola was talking about so Lola pictured the human she pictured herself. Having a material attachment to touching concrete and that's why she was motivated to make a new. I mean Dan did something similar right which is that once you see that battery jumping. Everybody has that reaction okay what can we do with that battery jumping. It was like such great suspense then I loved it was like okay so what does it mean that the boundary battery is bouncing are we going to make it bounce So, of course the resolution is very complicated. I guess what I'm, I'm just wondering if that doesn't in some way question the very idea of lifespan, even more, even the idea that we that we think of materials I think that are just things that they are evaluated by the standards of even, even Felix what you just said of course the, the most sustainable building is the one that's already there but the most sustainable life maybe is the question we should the bigger slightly bigger question I do think that it's, it's a valid thing to make those things beautiful of course, but maybe there's even bigger continuum between human experience and the habituation that that materials do and the blindnesses of the, you know imply Yeah, but David's high low project challenges the buildings already their philosophy a little bit and it's like maybe, and Felix you presented the biological versus the technical cycle I think those are the interplay between whether something exists permanently or is designed to exist very temporarily and we don't really design that way. I think I mean, I always have a trouble thinking of something that actually has a closed loop technical cycle and this is sort of maybe all the way back to Kiehl's presentation of like really the externalities of the things in the technical loop it's really hard to get rid of all I don't know if anybody has a good example. I mean lol I think you're coming close and some of the projects right some of these things are cycling. But there's always like as I was picking on Felix like there's a crane in the picture. Did you include the crane having to lift the stuff as part of the cycle that has emissions and it's running on diesel, etc, which is always the thorn in the side of the picture of the cycle. I think Kiehl does a wonderful job of sort of setting up the problematic of that, but I don't want it to hinder the discussion, maybe as a proactive question. What are some ways that we maybe move toward that or you've experienced good aspects I think the drawing certainly helped to bring in a lot of those other externalities but maybe there's other examples. Even with batteries maybe. Moving back to beauty there's a really interesting notion of, of course, sense of aesthetics as individual and very similar to you for us as an engineer thinking about aesthetics and design and beauty might exceed my, you know, a set of not saying knowledge or skills, but referring to for instance the biophilic design paradigm, which looks at it from an evolutionary biology point of view there are aspects of beauty of interaction with the natural world that we're actually as human beings were evolved to interact with in a way that enhances our physical, mental well-being and health. So, I think that's also an interesting aspect of, you know, the interaction with the microbial world and with living spaces that kind of interacts with our own living experience in a sense of that. Yeah, I was thinking, David, as you choose what to draw. I mean, this is basically your five models of research with a five. Yes. Five, drawing is five, right? Yeah, drawing is a fifth. I mean, that's a loose framework. I just kind of came up with that for this. It's really good because it answers the question that Forrest and I are frequently asked and are asking ourselves, which is, okay, so since concrete as an industry is so vast, so massive and in a way are all of these conversations point out what a small role the architect plays in all this. And thus, but the architect draws, renders visible and locates human in a variety of ways. And so when I see the Stuart Brand diagram of how buildings learn, which looks like a house but is really still kind of a humanoid, you know, internally consistent with the layers of skin. In a way I want a replacement for that. And I want a diagram that shows us passivation, like passivation is a concept that until I did this research about reinforced concrete I didn't understand at all. It just wasn't something that I understood as a as an option. It's not something that you really want to. Audio kind of dropped out. Yeah, something you want to. Yeah, it's just your audio dropped out a little bit. I don't know, maybe something fell on your mic. It seems to me that passivation, for example, is either something that happens to a concrete or it's not. I mean, the diagram we need for that is almost like a branching tree, like so, so there are things that you could draw that would not be quite so centered on the material centered on, you know, like the, like the Stuart Brand concentric diagram. I think that the question that that leads to there was timescale I guess, of that diet like where that because you did that David and trying to bring in timescale into the frame of that. The sort of what is the process there's a process, but then the process has a time scale and Dan brought this up doing batteries lifespan is a totally different space but the mechanisms that play are very similar to these very long time scales and concrete and materials that you're depicting. And then to Keel's point about the wood cycling I think the biggest problem within the wood whole wood sector is whether you're looking at like 100 year cycle of the forest or what we tend to do is take this one little moment where we took the tree down. And now the trees in the building and that carbon now suddenly is negative emissions for some reason, even though for the broad scope of time it really matters is what's happening in the forest ecology, from which the lovers coming right. I don't know if tie how much dynamics, we really are able to capture in sort of these varying timescales that Dan I think started within his top two. Of course I think it's a good way to talk about drawing because I agree that we have to, like as architects, like it's the fundamental conundrum of architecture and thermodynamics or ecology is that we, we have to draw these things but we can't draw energy, you can't draw ecology. You can draw the artifacts or the kind of states of certain things. So I think it's an error to kind of, you know, like I'm glad that we're drawing more things more processes kind of expanding the system boundary a bit but we're still drawing them in Cartesian spaces, we're still drawing artifacts right now we're drawing the tree and the tree or something like that, but, but we're still thinking through Cartesian means and I think that sets a real clear upper limit on, you know, we need to learn how to model in Lagrangian terms, if we want to really be following pathologically in a rigorous way, in a scientific and philosophically rigorous sort of way right so, you know, architects do some things in like Orlerian environments where we simulate a flow of air or something like that and I think we have some capacities for that but thinking and practicing in a Lagrangian way is just sort of like outside of any work that I've ever seen in architecture. Yeah, but it's absolutely the kind of design space that we need to be thinking about and having real conversations about these topics and it's, it's a super interesting challenge I mean it's it's most of my studios are about some kind of Lagrangian modeling method, but it's, but it's sort of like outside of our vocabulary it's outside of our imagination and, but I think it's the key point like moving beyond a kind of Cartesian or Orlerian design space is at the heart of all of these questions. You showed the diagrams of Odom I mean, and worked through that and various various people worked through that and then David you had that one diagram of the body computation lab with like origin of the tree. Somewhere in between there I think is a question of engagement in the design process, I guess, to Kiehl's point about where we bring time scaling can you do different, a completely different philosophical thinking about presentation and representation. That really brings those into the, for lack of a better word, the creative process on the design side. So, there is I think another thing of a time it's time it's just we should touch on in the Q&A which is about space, we haven't really touched on how much all of this changes as you change locations. And what's available in terms of how the bringing in climate you know the climate itself is changing right that's one of the feedback loops we're all acutely aware of things are shifting but also temporally and spatially we tend right now to build, especially because it's the same in every place but moreover just in general all the materials Lola you've been talking about they all are much more locally specific and I think closing some of the cycles has to do with understanding that I mean comes back to the point from the last panel about local materials for concrete concrete still made locally but it's a global industry. There's all kinds of ways in which those aspects spatially play out and how we think about what comes after what could be do we go to a more locally resourced means and mechanisms Lola pointing to or are there ways to close the technical loop in design our cities as Felix sort of poses, or systems that we might employ it's better incorporate the design upfront. Part of the design so I think there's just plenty. I don't think we're ever going to come to an answer today, but I'm really enjoying contemplating the many different avenues you may be I'm optimistic that we have the avenues but I'm still challenged as to what is the one way to think about what just happened in this panel is that we just are getting finally closer to depicting material decisions design decisions that exist both in engineering and in architecture where people really do ask themselves what does this. What does this, not what does the brick want to be, but what does metal want really what does it, you know that moment when Dan said that he's two mentors were somehow debating what metal wants to be. This is essentially design decision but we are now expanding hopefully enough the, the, the seriousness with which we depict that as not just a folly not just an individual folly that is a technically constrained environmentally portendous decision but one that is a decision indeed one that has, you know, agency and the end of and we have to account for those agents but the more we describe material processes as being subject to those decisions, and the more we then describe how designers act in the world together I think the better off we are towards having a materially accurate or material in informed decision across discipline between you know history and theory and technology, not to bring it back to us but that's where we started. I want to add one more, I think that's that's a good way to frame it, like, what is, how does the drawing interface with the point of decision making. One thing I've been struggling with a lot is trying to draw scalability. So I don't mean scale and note in the idea of multiple scales, I mean, like, could we draw the potential for one type of design decision with materials and energy to have like a lever effect, or to be a solution, I mean it's it's in a way. I know there's some, I know there's some potential pitfalls here but it's like interfacing Al Gore's pie chart of carbon emissions, you know, with certain design decisions. Like, are we really going to make a difference by certain decisions in the right amount of time, speaking of time. Or is this too much of a, of a one off. And that would be the point also where we would have to try to anticipate and even draw unintended consequences and that's the, that's the kind of thing that comes up with a lot of the systems thinking like, how do you, how do you ensure that by making, you know, mass timber as a replacement for concrete, or a better version of mass timber which might be used bamboo because it can grow quicker. What is the time, like, what, what is the scalability of that type of decision. Could it, could it scale up, could it have an impact, could it change the needle in 10 years that we need, and would it involve all of these other unintended consequences like deforestation by accident because of various other forces. Again, I think in, in, in defense of drawing. I think just by asking those questions and by having the time as a way to like debate them struggle with them even fail to represent. That's a good way to expand the thinking and the role of the architect and address the urgency. Yeah. Yeah, I think that's a great rate of change. Yeah, thank you panelists for really indulging us and and presenting amazing work and presenting together I think it's also really compelling how it coheres as a new picture of what's going on across across materials through energies.