 The next panel is on steel and cement industries. Our moderator is Diora Dressel-Hassmann-Rae from Stanford University. And we have five excellent panelists, Pequis Pistorius from Carnegie Mellon, Eric Trussovitz from Stanford University, Pulakesh Mukherjee from Imperative Ventures, Tiziana Venorio from Stanford. And we can show Guha from Tata Steel. So we have a good variety of people and I'm gonna pass it on now to Diora to run the panel. Diora, take it away. Hi, thank you, Richard. And thank you everyone for coming for this panel. It's my pleasure to introduce these excellent panelists. I will start off with brief remarks. I think that at this point, a lot of people have mentioned the very large needs in decarbonization, both within steel and cement making industries, just to summarize that and make sure we're all kind of on the same page. I will remind you that both steel and cement are gigaton per year types of industries which present problems and challenges both in the science of scale and in understanding how to convert this very large infrastructure that is considered classically difficult to decarbonize. So in this panel, we will be discussing both the science and industry pictures of what decarbonization looks like in these industries including an overview of the science, policy and infrastructure needs that we really have to go about this. So in our panel, we have a number of speakers. So first I'll introduce Chris Pistorius who is a PASCO professor of material science and engineering at CMU and is the director of the Center for Iron and Steel Making Research which both trains are new engineers in this area and builds research within that area. Then let's go to Tiziana Benoria. She comes to us from Stanford University. She's an associate professor of geophysics and by courtesy civil engineering and environmental engineering and the associate dean of educational affairs. She has some very interesting research that she'll be telling us about in the cement making industry. Then we have Eric Trusowitz who is an executive and entrepreneur who has more than a decade of experience working globally at a top multinational cement firm and in management and strategy and finance. Then we also have Pulakes Mukherjee who is a managing partner at Imperative Ventures with over 10 years of experience in international business development, sales marketing and chemical process scale up. And then we also have Marie Ganshu Guha who is the head of Tata Steel's Advanced Manufacturing Research Center which has some really interesting new directions that we will hear about in advanced materials towards those goals. So with that, I will now turn this over to Krista Storius to start us off with a introduction to steel making and decarbonization efforts there. So in 10 minutes or so, just a few perspectives on where we are and where we need to go and some of the challenges of getting there. So in terms of where we are right now, the global iron and steel industry is very carbon intensive really because of the reliance on blast furnace iron making. So this chart shows the historical development of how much coke primarily is used in blast furnace iron making. And what it does show is that the industry has been pretty good at optimizing the blast furnace but from the leveling out, you can see it's gone about as far as it can given the thermodynamic limitation. So we're stuck at around 450, 500 kilograms of fuel a combination of coal, coke and natural gas. That means if we take an average carbon concentration in there of about 88%, that translates to 1.6 tons of CO2 per ton of hot metal. And if you add the other emissions from center production and coke production, you easily get to the two tons. And there's not a whole lot one can do about that if one sticks to a blast furnace unless one starts recycling the top gas and sequestering the CO2 that way. And in any case, a blast furnace needs around 240 kilograms of coke to run. So we need to move to something else. And that path is I think pretty clearly electrification for the most part. So electrification of both steel making and iron making. So just to be clear about how I shall use the terminology. So steel is the final product which we make into car bodies and washing machines and bridges and the like. So it's mostly iron containing a fraction of a percent of carbon. What we call iron in this industry isn't really the element if E, it is the product of having reduced iron ore, so iron oxide and it can contain around 4% carbon. If it was made in the blast furnace, it can contain close to zero carbon if it was made by direct reduction, but it does need to be refined further to make it into steel. So electrification of steel making and of iron making, I think it's useful to distinguish between those. And in terms of electrifying steel making, that's something we have largely done in the US already. So 70% of the production of steel in the US is by electric furnace steel making, taking largely scrap and recycling that, which does have a pretty small carbon footprint compared with blast furnace iron making. So the electricity consumption for North American electric arc furnaces is around 0.4 megawatt hours for a ton of steel. And the CO2 emissions are somewhere around 300 or so kilograms of CO2 per ton of steel. This includes electricity at the current average CO2 emission factor and one can manage this number down a little bit more, of course, by using renewable electricity. And about half of that CO2 is actually emitted in the furnace by burning carbon and there is definitely room to optimize that and that's something that we've been looking at to some extent. The challenge to continuing down this path is the quality of scrap. So the main raw material for this kind of low carbon steel making is previously used steel that is simply remelted, reformulated. There are certain elements that are more noble than iron and build up during this process, the worst pretty much of these is copper and this chart shows various scenarios projected into the future as to how the amount of copper in the scrap supply is going to build up as we electrify our lives and how the existing steel grades will no longer be able to absorb that much copper. Copper has various quality issues especially surface quality if there's too much of it in there. So we are definitely heading for a crunch in terms of scrap quality which is a real danger to our ability to maintain this low carbon recycled steel path. The alternative then is to electrify the iron making step. So where we take iron ore, iron oxide, produce that like fresh iron which then doesn't have any copper in it and one set of options then starts with green hydrogen. So hydrogen produced by electrolysis of water and there are currently a couple of ideas of how to use this. The one is direct reduction in the shaft furnace. This is very similar to the current direct reduction operations which already run at 60, 70% hydrogen. So it's really just pushing it to 100% hydrogen and then melting that product in an electric arc furnace again existing technology. So the hybrid pilot plant in Sweden is an example of bolting these technologies together and demonstrating that it can work and there's no obvious reason why it wouldn't. There are some detailed things around the mechanical strength of the product here and some loss in melting and of course current arc furnace operations really need carbon for the quality of the product but those are I think engineering issues that we shall be able to solve. The alternative is what is being developed by Posco which is use a smaller size feed material reduce that in a fluidized bed again melted in an electric arc furnace or first melt it with some carbon and then convert that in a traditional oxygen converter which has some quality advantages potentially. So again, these really rely on largely proven technology. So it basically can work and there are various plants under construction to demonstrate that that's the case. Something that is worth noting here is the overall electricity consumption which is largely that to make the hydrogen and that comes out at one order of magnitude more than when we recycle steel this is now four megawatt hours per ton of steel in round terms. An alternative technology then is to do direct electrolysis so this is rather like the process used to make aluminum. This is currently running at pilot scale and it's a process being developed by Boston Metal. So it's all in one unit. So the heat is generated by mostly omic heating oxygen produced at the anode and iron at the cathode and the projected electricity consumption is four megawatt hours per ton of steel seemingly an inescapable number. So to move down this path as a number of challenges first of those is the cost of electricity which is then reflected for example in the cost of green hydrogen. So this is a rather straightforward calculation based on current and projected efficiencies of the proton exchange membrane type electrolyzer and the US average electricity cost. As you can see most of the cost of making green hydrogen is indeed electricity. So to move down this path cost effectively in a very competitive steel industry will very strongly rely on low cost electricity. There is of course the Department of Energy target of bringing down the target to $1 per kilogram. And again, the only way to get there really is low cost electricity. So that's the one challenge. The other is just the sheer physical footprint of renewables maybe not such a big issue here in the US but as I'll show in a minute definitely an issue in other large steel making countries. So this is a view of what is stated to be the world's first solar powered steel plant. So this is plant that melts scrap. So it's that around 400 kilowatt hours per ton of steel electricity consumption. This is part of the solar farm that powers that plant. So it covers around 600 hectares. It's a 300 megawatt hour plant to produce around one million tons per year of steel. For comparison, the US produces in total around 80, 80 million tons of steel per year. So if we think about how this would look like on a global context in terms of the large steel producers, there is one way I think of looking at this and what this plots is on the X axis the tonnage of steel in millions of tons per year produced in the 20 biggest steel producing countries in the world. Y axis is the total electricity produced in each of those countries in terawatt hours in 2020. And then these two lines, proportionality lines then just show how much electricity would we need if all of the steel were produced either from or. So iron making, that's that four megawatt hour per ton number or from recycled scrap which is that 400 kilowatt hours per ton number of course in order of magnitude less. So for example, oh, and the other thing to mention is the size of these circles around the data points indicates just the area of the country. This is a crude measure of is there room to build out renewables, whether it's windmills onshore or offshore or solar arrays but no measure taken off is there enough sunshine or anything like that. But if we look at a country like South Korea that produces a lot of steel, if all of that were to be to produced by electrolysis either directly or via hydrogen, that would consume a third as much electricity as the whole of South Korea currently consumes. In the U.S. it's a much smaller fraction really because our denominator is so much larger we produce so much electricity for other purposes but this I think really means there will be this global trade in hydrogen which there are various arena reports that indicate this as well. So it's really a global effort that will be required to get there. So as we move in this direction just the last couple of points, how can we squeeze the current technology down in terms of CO2 emissions? In the case of the blast furnace there is some promise to pre-reducing the feed externally using natural gas and feeding that to the furnace essentially using the blast furnace mostly as a melting unit. The most promising really is maximizing our use of the electric furnace, whether it's the melt, direct-reduce iron, definitely maximizing scrap use and then also looking at how much carbon do we really need to use in that while of course using renewable electricity. This is just a simple summary of this spectrum of possibilities and there's a short recent communication that explains these but you can see there is a wide range of carbon footprints achievable with existing technology. For example, that's the existing electric arc furnace operations, if we run that with renewable electricity we get of course much closer to zero if we have to make DRI using natural gas then we're back up around 900 kilograms. As a closing point, this industry has changed considerably in the past. So there is definitely room and opportunity and willingness to change. So for example, this shows how the different oxygen converter processes have changed in steel making. So for example, the basic oxygen furnace took just a little bit over a decade to completely overtake the previous dominant technology of open-arc steel making. So I think if there is a compelling technical solution combined with a compelling economic necessity this industry can definitely change and quite rapidly too. So thank you. Those were my few thoughts. Thank you very much Chris for a very interesting talk and perspective on this. So now I will turn this over to Tiziana Venorio to give us an introduction and perspective on cement making and decarbonization strategies there. And I will also mention that for those of you who have questions or comments please do include them in the chat and we will get to those towards the end of the panel. Thank you. Thank you. Thank you, Liora. Good morning everyone. Thank you for inviting me to contribute to this workshop and share my perspective on decarbonizing cement manufacturing. I'm going also to share today the approach we are taking at Stanford to decarbonize cement and in particular the philosophy behind our work which is tackling cement decarbonation requires a geoscience and engineering partnership especially if the goal is to decrease indeed carbon emissions but also increase the serviceability and durability of concrete. If we think that modern concrete has relatively short lifespan in average 80 years which certainly does not bode well for its total carbon footprint. But let's start with what's at stake here. Concrete is the most commonly used man-made material on earth. It's a construction materials used extensively in buildings, bridges, dams and wells. And recent data here show that 30 million tons of concrete is used each year's world-wiles and the demand is increasing. The demand of concrete is growing more steeply compared to the demand of steel and wood. And this graph also shows that on the per capita standpoint this corresponds to three times as much as 40 years ago. Many of these applications also I have to say that requires performance in harsh environment whether it's at sea or at depth in the subsurface. Let's think for example of methane leaks from well-bore cement sheets. But cements we know that has a non-negligible carbon footprint. Its manufacturing is responsible for 80, 11% of the world's CO2 emissions. And here I like to emphasize that although cement decarbonization is an engineering problem at the root of it, the biggest challenge in the cement making comes from the field of geoscience. In fact to paraphrase the head of research and development at CEMEX, he mentioned that decarbonizing cement is not rocket science but actually rock science. Why? Fundamentally for two reasons. The first reason is that cement manufacturing starts with limestone rocks made of calcite or calcium carbonate minerals which are thermally decomposed to produce lime. Calcination we know it's a high temperature process that requires the use of energy. Generally energy comes from the fossil fuels. And that is responsible more or less for 25, 30% of the emissions. But then the carbon decarbonization process is basically breaks down the molecule of calcite or calcium carbonates to produce calcium oxide also known as quick lime. And that process releases CO2. And this process contribute to 60%, 70% of the emissions. I'm not considering here the transportation. Mining carbonate rocks for the cement industry is estimated to be about two billion tons of rocks per year worldwide, which translate into 1300 megatons of CO2 emitted per year. This figure correspond roughly to the emissions generated yearly by all cars circulating in the US. So the first lesson that we can draw from this is that even though the ever-changing landscape of a more efficient energy technology may offer solutions that may help reduce the emissions that comes from the energy use, searching for an alternative material that drastically reduce the majority of the emissions that comes from the calcination of limestone rocks remains absolutely the priority. And so finding an alternative earth materials is a rock science problem. Then we know that calcium oxide is mixed with alumino silicates, clay ash, fly ash, gypsum that serves as a moderator and all together is the recipe for Portland cement. But then to make concrete, cement is mixed with aggregates, generally sand size, gravel size, materials, water and then steel bar. And this is because the tensile stress of, sorry, the tensile strength of concrete is low. And so steel is used as a reinforcement to prevent cracks from propagating. And it's really the reinforcement that leads to the second issue. Not only data indicate that the ordinary reinforced concrete emits approximately 15% more carbon dioxide than the voided concrete system, but also the corrosion of reinforcing steel is the leading cause of deterioration in concrete. But nature may come to our rescue. We know in the geosciences the fracture rock system cement naturally and exhibit high strengths without any reinforcement. In fact, we can think of active falls that you can see here of the earth crust as a large scale kiln factories. They mechanically pulverize rocks to the micron and finer scale during earthquakes and then internally channel heat that prime the sediment for fluid mediated reaction which eventually form a concrete-like rocks without any apparent reinforcement. But actually reinforcement exists just at a scale that is not visible to the naked eye. In fact, nano does not always equate with manufacture. This SCM here, this SCM image shows the aluminum silicate cement of certain rocks and cement appears as a tangle of nano minerals fibers. You can see here the scale 500 nano. Other times fibers minerals are also well aligned. So this shows that earth is an excellent nano technologies that use water for its chemistry. However, we know from the engineering that fibers are added to material to increase toughness and stiffness as they bridge fractures and also deflect the path of cracks. So overall, we know that fiber-enforced materials are able to accommodate strain and absorb strain energy preventing brittle failure. But then the addition of fibers into materials leads to a couple of reflection. From a practical point of view, there is a limit to which we can mix fibers into a paste because we need to know that the higher the amount of fibers that we add to any slurry, the greater is the viscosity and then the lower is the workability of the composite. The second reflection to make here is that we need also to increase the strength at the fiber matrix interface. If the shear strength here is low or the bonding is poor, we have fiber bonding, which clearly decreases the strength of the composite. But even in this case, nature can help us. We have seen that rocks may exhibit fibers that may be entangled and aligned. And in this plot here, I show that the stress and strain behavior of different arrangements of fibers from disordered here to entangled. And entangled arrangements, disorder arrangements show a more ductile behavior while aligned microstructures exhibit a more brittle failure. This is not surprising because we know, for example, that ropes that are made out of braided or knotted strengths are known to be tougher. And that's what we want for cement. In this realization, I want to mention that the number of fibers per volume unit is the same. But in order to maintain the strain and then increase the strength, we need to make this fiber try, which means increase the number of fibers. So we are using, and this is the work that we are doing in Stanford, a geomimetic approach that is using all the aspects that I've been talking so far, as with biomimetics that are brought as many transformative materials from Velcro to adhesive inspired by the gecko skins, we are harnessing earth design to mimic certain rock functionalities and processes. And this includes a new rock composition and also fibers entangled entanglement for reinforcement of the nanoscale. So we are using an alternative binder precursor. So basically a new rocks that replaces limestone. The plot here shows the mass loss that the new binder precursor experience upon calcination. You can consider the mass loss as a proxy for the amount of CO2 emitted upon calcination. And for comparison here, I'm showing the data from limestone. So the difference which is given by the two slopes is striking. At the same time, we're also studying how to grow mineral fibers within the binder. You can see here that fibers are literally sprouting from the paste as it were a living creature. We are also working on how to increase the number of fibers per volume unit. And indeed, we are working on how to increase the entanglement of these fibers. This approach, I have to say that order comes some of the disadvantages of a carbon upcycle. Carbon upcycle is a technology that uses capture CO2 and then recycle CO2 into the fresh slurry for curing. And this process leads or transforms supercritical CO2 back into solid carbonates. But this approach has high cost because it requires changing the manufacturing chain. It's also limited to precast, but also the most important aspect to highlight here is that carbonation or carbon upcycling basically precipitates calcite. And calcite or any carbonate minerals as well known in the geosciences that it's a mineral prone to dissolution and also a brittle mineral. These are some of the experiments we are doing to show how the precipitation calcite makes the overall cement more brittle. And this is not surprising if we, for example, think of fructability of shells, the amount of the shells that contain more carbonate minerals are more fracable because they are more brittle. So in conclusions, I hope that I show that cement decarbonation is as much an engineering as a geoscience challenge. And this partnership is crucial to cross pollinate knowledge and also leverage knowledge across the geoscience and also material science and chemical engineering. Here I'm showing the my collaborators at Stanford. After all, we know that it takes two to tangle and I would say also to tangle in this case. So I showed that we are working on a new natural rock plant, so a new rock that provides a more sustainable binder precursor. We are also using a geomimetic approach that draws inspiration from how earth does chemistry and then earth chemistry contributes to the mechanics of cementation. And then I also think that it's very important and time is now to cross pollinate knowledge that we have around nano minerals in the geoscience and nanotechnology to study the nano scale of long polymers or fibers control the orientation of mineral fibers to enhance the reinforcement of the bulk material at the nano scale. And with that, I thank you for your attention and I look forward to the discussion. Thank you. Thank you very much, Tiziana, for that really interesting talk and great perspective. There was, I think, one brief question in the chat. Tiziana, can solid carbon particles be added to concrete? Absolutely. They will serve the same, basically a technology that rely on the way, for example, fibers are added to materials, but let's still consider the fact that carbonate minerals are prone to dissolution and also they are brittle. So definitely the strength goes up as I've shown very rapidly, but then brittleness also increases. It's an interesting thought process of both thinking towards the properties of the products as well as thinking about the strategies towards the decarbonization efforts, right? Because they're so strongly linked. Yeah, absolutely. Very interesting. So now I'll turn this over to Eric to give us a perspective coming at this from an industry picture. Yeah, thanks for the opportunity to present. So what I've tried to do here is just adapt a little bit what I, how I see emerging technology for cement CO2 reduction to the topic of this session, which is electrification. So I'll just go through a little bit of background about the industry. I'll go through a little bit of framework that I personally use to look at things in terms of their feasibility and scalability. And then I'll just touch briefly at the end on electrification to open some questions about it. So, yeah, a global cement industry, 4.1 billion tons of annual production, around 2.8 billion tons of CO2, the estimates of global CO2 range pretty broadly from, I've seen 6 to 8%, I see Tatiana, you had a higher estimate. So I mean, that's great. That just means we're working on the right problem, right? And this is a growing problem. So cement utilization is gonna grow to 2050. It's primarily in the developing world. And it's a question of human development because the developing world needs to build out infrastructure and housing and basic building blocks of its economy. And that cement is at the basis of all that. And the modern, just to give an overview of what's the modern cement production process, you're basically digging out millions of tons of minerals from the ground, and you're crushing them up into a fine mixture called a raw mix. Primarily using limestone and clays and minerals like that, you're putting it into a raw mix, you're heating it up. It passes through a phase called calcination where the CO2 that's attached to the calcium and the calcium carbonate is released. That's a calcination process that helps around 900 degrees Celsius. And then from there, you go into a kiln and you center it and you create the products of an intermediate thing called clinker. And then you co-grind that with other things like gypsum or other kind of waste materials and things like that, which are called supplemental cementation materials. It's very, very highly capital intensive. You need hundreds of millions of dollars to be in this business. You probably need billions because having one cement plant is usually not a, and there's only around 2,500 plants in the world. And the basic cement plants can produce around a million tons of cement or more to be economically viable. And actually it's gonna release, it's gonna put in a whole bunch more minerals, probably 1.5, 1.6 million tons because a lot of that raw material is actually just gonna go up in the air as CO2. This is just what it looks like. You can see the cars in the parking lot, just for scale. So it's big. And this is a plant in Latvia that I had some close interactions with when I was working in industry. And then if you look at the production process, you can see basically what I said here is you have all this calcium carbonate. CO2 just gets released from that calcium carbonate. Your massive solid raw materials is reduced. And then you go at around 900, you pass into these other phase changes and things called in cement, chemistry, parlance, A light, B light, et cetera. And you have to control the phases of this clinker material, but they're primarily calcium silicate type materials that are coming out to form this clinker. And then it's reactive. It's hydraulic. When you put it with water, water is then integrated into the structure of that thing. And it creates a cementing effect. So I think the most important thing for every single person to understand who wants to do something that's been industry is it is entirely governed by cost. It is a local, very highly competitive, usually commodities market. And it is incredibly optimized. So it costs like $20 to $40 per ton of material of cash cost, primarily for energy to produce a ton of cement. And this is just unprecedented. I don't know many other industries that could produce tons of material for this kind of order of magnitude cost even. So that's like the biggest barrier that you have in the cement industry to innovation is if something increases a variable cost per ton by 10 cents, people will not like it and they will not adopt it. So that is like really important for everyone to understand. Where does this cement cup from? We talked about this process of calcination where you just basically take 40, 44 or so percent of the limestone itself and just release it into the air. And that's this calcination process. That's actually by now, this is an older graph. So this is by now around 55 or 60% of all the emissions in the industry. Primarily the rest of it is coming from combustion of fossil fuels to produce that temperature of 1500 Celsius. So I would say probably just important to know in 2019, there's real tipping point for the industry prior to that. It was like there was some CO2 focus maybe in Europe because they had a bunch of regulations there. In 2019, the capital holders really started to get involved and actually the price on CO2 and CO2 regulation started, people started to see the writing on the wall that that's coming. So there was a real tipping point and the top executives, then companies started to pay much, much more attention. I would say it's the number one or number one, two, three issue for all the major multinational cement companies right now. That resulted in 2021 in this new plan. It was actually a lot more ambitious than the old plan. The old plan was not ambitious at all. And this is much more ambitious. It still has a very large segment of carbon capture. There's no place I see in this plan. There might be some calculations for electrification but it's really more like, hey, we're gonna decarbonize the electrical grid and that's gonna take away 5%. It's not about using electricity instead of combustion to heat the process in this plan. So that's really absent. And I think actually there's interesting things to do that I can touch on at the end. And then just with regards to my own kind of approach to thinking about the industry, I did a wide research on all the ways that industry and innovators are trying to reduce CO2 in the industry. I kind of just classify stuff in a very simple way for myself, material energy or capture, those are the main buckets and then some sub buckets under there. I don't think we need to go into detail but that's just my framework for thinking about it. I looked around and actually found an enormous amount of innovation much of which has not scaled for the same reasons that we talk it's all more expensive or a lot more expensive and where it has a variable cost benefit, it has scaled alternative fuels, use of industrial waste as supplementary cementitious materials, the adaptation of the dry process production to replace wet process production that's scaled pretty broadly because it's a variable cost benefit. And here you can just see a lot of materials innovation which faces some other hurdles and then innovation and energy and capture. And this is just a look to say, hey, there is a lot going on in the industry and why are we not seeing this overtaking the process? And so I just came up with a little bit of a framework for some sector specific considerations for the feasibility, I guess viability and scalability of stuff. And those are, you need billions of tons of extraordinarily cheap raw materials. That's the number one thing that a lot of innovations fail on that. If you wanna change the material, you're kind of built on top of limestone quarry, all the trillion dollars of assets in the industry are already built on limestone quarries to go and change that. You have cost stuff, not that it can't be done but it's a hurdle. The economics, we comment that a little bit extremely low variable cost that's probably the biggest hurdle for most of the technologies. The incumbents, there's about a trillion dollars of deployed capital infrastructure, real oligopolistic kind of nature of the industry. So you need to be big and you need to kind of be synergistic with that trillion dollars of capital stock. If you can, if you can't, you need a trillion dollars for new capital stock but also you're gonna have all these people fighting you. And then the last one is really the ease of use, how the thing fits in regulations. Some men builds buildings, people live in buildings. There's a whole host, enormous, enormous amount of regulations and interlocking and completely separate regulations at all levels. The national level, state level, local level on public safety. So it's really hard to change this material, improve that in 30 years, that building's still gonna be safe with a new material and stuff like that. So a lot of this applies to materials. And I look at this as a process. So it's sort of, one is like the end, what you put in, two and three are sort of like what you do in the process and four is what comes out of the process. So that's sort of my own framework for thinking about this. And then I just kind of put this in a, I don't know, some sort of a format that you can look at the sector and look at innovations through this. I just said, okay, if you have widely available economic raw materials and can produce a material that in and out are okay, that I call that industrial feasibility. And then if the very book costs and the capital costs are okay, I call that economic feasibility. So when you look at this, you can look at the sector. And this is just some examples. It's actually from a couple of years back, when I was looking at the sector in this and I started to identify, hey, there's interesting things that are already generally known in the industry. There's four that I identified at this point that I thought were really interesting in this framework. And I think with regards to electrification, there's not real challenges for industrial feasibility because you're generally using the same raw materials and producing the same material at the end. It's really more a challenge of economic feasibility and an especially variable cost. Well, I'll comment very quickly on these four and then we'll talk a little bit about electrification. So these four that I identified at that point, one of them is really binder efficiency. It's like the industry is now, I think, taking this up a lot more. It's just the concept that in concrete where you use cement as a glue with sand and agriets, there's like a whole bunch of inter-particle space that doesn't necessarily need to be there in the microstructure. Like you can use particle-sized optimized fillers and it's the same if you've ever seen a video of someone filling up a jar with marbles and sand and water, it is the same concept at the microstructure level. Can you use particle-sized optimized fillers to reduce the need for cement? So calcium, silica, hydrate doesn't need to fill up this inter-particle space because there's already a bunch of particles there. That's kind of the concept of this one. A lot of research on how to use chemical admixtures to control rheology, gradation, like dispersion, workability of the material, which is really promising, especially by Van Der Lake John in Brazil. He has excellent, excellent research on this and this is some of that. And then another one is very commonly used supplementary cementitious materials which are often either natural or industrial waste derived. That's something that the industry is already using pretty broadly, but some of those are, fly ash is linked to coal-fired power plants. So that's phasing out. You really need to develop an ex-class of supplemental cementitious materials. And you can do that by getting a very cheap beneficiation technique a lot of the time for other things that are around, whether they're natural or industrial materials. And if they have some amorefacilica fraction or if they have a reactive metal oxide in it, you can, or if you can beneficiate it, so you have a homogenous and cheap material that has that, that's really good. And actually electrification has a really interesting potential application in the thermal beneficiation of some of the emerging SCMs, especially calcine clay, I think, because that happens at a temperature where electrification makes more sense. So that's a SCMs, both traditional and emerging. Carbon capture, we could talk a lot about it, but I don't think we need to spend a lot of time on that. The basic issue, again, is cost with that. And a lot of that's the parasitic energy load. So if you're gonna regenerate this sorbit and you need three gigajoules of energy per regeneration of that sorbit when you only needed three gigajoules to produce that in the first place. So you double the energy intensity of the sector. That's a problem. One of the most interesting projects I've seen is indirect calcination. This is a project called LILOC, which is owned by a company called Calix. And that just says, hey, if you heat this raw meal indirectly, you get a pure stream of CO2 off of the top of the factory. So it's not all mixed up with the combustion emissions. And I think that's a very powerful idea because you don't have parasitic energy load or increased OPEX, but hey, what do you do with that CO2 in the end? That's the other problem that still needs to be solved. And again, electrification is really interesting here. This is a gas-fired version, but Calix has also developed an electrified, fully electrified version of this, both for magnesium and for calcium and it's used into the cement process. So that's an interesting innovation, I think on the calcination section of the cement plan. And calcination is interesting because it happens around 900 and not 1500. So it's a lot less challenging for electrification. So that's about the carbon capture. And then the other one quickly to highlight is just digital. There's a lot of smoke and mirrors in digital, but there is a role for machine learning and heavy industrial process optimization. You can get in reality 10 or 20% efficiency increase often by just targeting higher, like a smaller margin of quality on the clinker production or things like that. And then if you apply this machine learning between the cement industry and the concrete industry, like you can get significant additional improvements on that. But this is, it's hard to find in the sector what's real and what's not, but there's probably two companies in the world that have something I think is really worthwhile on this. And this is just like one of these little companies, it's not a big company at this point, but they have really interesting a optimization models for this thing. So one company that does that is called Optimedia in Northern Spain. They have a really interesting real-time optimizer. Another one is Ferro Labs out in New York, which has an excellent system for process engineers to get that additional 10 or 15% from heavy industrial processes, steel, cement, et cetera. So I think those are all interesting. Here's another optimization model. So that was those four that I had identified for this. I kind of had a thought, hey, what's emerging now? And three of those, CO2 mineralization, I think there's a lot of synergistic mineralization technologies that are in, can be used in the cement industry. Biogenic solid fuel, especially carbonization of methanogenic, high moisture content, waste to produce next generation biogenic alternative fuels, I think is interesting, but most interesting for us is really, can you use intermittent renewables to produce very high temperature heat via electrification? And that's, I think, an extraordinarily powerful thing. Why? Because if you look at electrification, generally the calciner is less difficult to electrify than the kiln. The calciner operates around 900 or 1000 Celsius. They don't have the same material issues that if you're gonna try to heat things to 1500 or change of 1500 Celsius process, you would have. So that's a lot easier. It's calciner is actually more than half of the energy generally in a cement plant because calcination actually, in addition to the heating, needs a lot of energy to take place, to break that bond and to release CO2. So that, and the other thing about that is, if you do direct electrification of calcination, you again get the CO2 concentration benefit because you don't have combustion emissions in that segment. So it's very interesting, how do you, like this is actually ongoing, like I mentioned, Kalex lilac is doing electrification via indirect calcination. There's other kinds of electrified calciners that are under development. Fortunately, I can't really mention because some of them are a little bit more internal industry confidential stuff. And there's actually even stuff on a like real deep research and projects that have been done on plasma fired full cement plant and full kiln process redoing by industrial companies that yields, okay, this is interesting, this can be done. And the biggest problem is again, the cost. And that is, if you need a base load 24 seven available electricity, it's a very high cost compared to combusting fossil fuels or waste which the cement industry does. And that is like the main issue that I see a blocking the electrification of cement industry is actually the cost of electricity. And I think the most interesting idea is to say, how do you take intermittent renewable electricity? How do you carve off the four or five or six hours a day when it's cheap because of the dark curve, when you can get these high concentration of renewables and then transform that into very high temperature 24 seven available industrial heat. That's the key problem to solve electrification in the cement industry, I think, because that will bring down the cost of doing electrification at least for the calciner and potentially for more of this cement plant. So if you can actually achieve that, I think that unlocks a lot for electrification in the industry. And then I would say the most interesting project that I've seen on that is really a company called Rhondo Energy that's in the Bay Area. This is a company that just says, okay, how do we bring thermal storage down to earth in terms of its cost and make it economically viable now? And here you can see a little bit, this is this dark curve from an example day in California in the concept of the company of, okay, we're going to charge at the time when a electricity is the cheapest, but we're going to deliver a baseload a renewable or baseload renewable electricity derived high temperature heat. And that is extremely powerful, I think for the cement process, because you can use that for the heating of the material, you can use that in the calciner, if it's around a thousand degrees Celsius, which is the company's already has very good success in doing a thousand or a thousand 100 degrees Celsius. But if you also can get to 1500 Celsius, which is within the target of the company, you can actually look at electrifying the entire cement production process. So this is an emerging technology, I think it's really interesting because it solves the problem of cost of electrification, which is really central to everything. You can currently electrify cement production, but no one wants to do it because the energy cost is six or eight times higher. But if you do this, you can bring that down. So it has a comparable or even sometimes lower energy cost than combusting fossil fuels, especially in jurisdictions where the combustion of fossil fuels is taxed at a CO2 level, like in the European Union. So for each ton of coal, you have 2.7 times 80 euros of additional costs. And this brings Rondo or thermal storage systems like that. I can get to these high temperature heat through load shifting during a day down to a very interesting cost, just on economics alone. So yeah, that's I guess the quick thing. I hope I'm within my time, but that's a little bit how to apply that framework to electrification that I can think of for this conference. Thank you so much, Eric. That was a really interesting talk and a very interesting perspective coming at this with your experience and kind of thinking about the process and how it connects to the industry priorities and the bottom line on cost. So I see we have some great questions. I'm gonna circle back to those questions afterwards so that we get a chance to hear from some of our other panelists. And so I will kind of open this up with a broader question, starting with Pulakesh and Muriganshu of what do you guys see as the kind of priorities in decarbonization and the strategies that are gaining the most traction versus Sina's meeting the most traction? First, thank you very much for the invitation. So glad to be here. Those are very interesting presentation. So the way we'll look at this sector and like any commodity sector and Eric highlighted that it's about cost. So first, does it work? Performance matters in this sector because we are talking about building safety is extremely important. And the second important thing is the cost part of it. So the challenge what I see in this sector is there are obviously today, there are solutions that you can actually make concrete without using any cement and the performance is there. The reason those are not in the market is mainly twofold. First is there's no framework or specification like ASTM code to bring new materials and qualify them. And second is the cost part of it. So given these two sectors where we'll look at and see what else can is happening. So people are talking about definitely the alternative fuels. Synthetic SCMs, which will be a substitute. So one of the places where you can have a major impact is in the cement, can you substitute? Especially if you look at ready mix today, approximately 75% is cement and 25% is the other material. Can you change that ratio? And actually use 25% cement and the rest as SCM and other process and things. Also critical, which has been highlighted a little bit in today's session and especially in the previous session of all the system level thinking is really looking at the life cycle analysis. Is it really better than the incumbent process? When somebody's claiming can stand up to the audit. And when I look at that, I look at the cradle to grave and you do that analysis and said, one is the incumbent, the other is the alternative process. Where I'm seeing some innovation happening, especially if you want to use other alternatives in the area of activators and add mixtures and chemistry will play a major role as well. Thank you. I'll turn this over to Reganchu now to give us that same picture from the SEAL perspective. So first of all, good morning everyone. And at the outset, let me thanks on behalf of Tata Steel for having me here today, I'm in this August gathering. In fact, being from steel industry, I could not agree more with Professor Arun Majumdar when doing his opening keynote. He identified steel along with two more industries. I think cement was one and another one was something else as vital to villains of this whole gigatron level of CO2 minus on the planet Earth. But he also briefly touched upon some of the reasons and after that several speakers also brought up this broad strategies for tackling these overall issues. So as per my thought process, I think that terms like decarbonization on electrification, these are kind of summarization of the overall strategies. But at the tactical level, we know it's not straight jacketed things like one size fits all. So for example, if I take example of our steel industry, so where blast furnace route of iron making, which is kind of the CO2 emitting monster of any steel industry. And blast furnace is a common process which is available in most of the large scale steel, large scale and integrated steel plants. And the reason for this is because the uniqueness and typical characteristics of these processes, because these processes again have several interlink sub processes. And not only that, I mean, complication doesn't end. So it also depends on several kind of inputs. I mean to say that the raw material and they keep on changing. So there are several parameters which actually comes into play. And that's the key reason why it is so, I mean, critical to address this whole issue. So say on that same example of blast furnace process, so if we tend to use hydrogen or natural gas as an alternate source of fuel, but we cannot use it uniquely or a similar solution cannot be used across different blast furnaces. So there lies the challenge. And again, another thing is that as far as electrification is concerned, so sometime I feel that we often use this term electrification for our own convenience without caring for whether the electricity produced is really green or not. So if it is not green, so then actually we have not cleaned up this whole entire CO2 mark. So rather we have actually played the game of passing the box. So that's what I feel. So, and to top it all, the most challenging thing especially in steel industry because this industry which is, I mean, most of the places that is quite old, I mean, this industry is here for centuries, more than century. So, I mean, adapting something, this new technology or retrofitting is a big bottleneck often, often times. So that's what we also feel. So, I mean, giving all these things, I think yesterday one of the speakers see very nicely put it. So he said that basically we have to adopt technologies which are across different technology readiness level. So maybe we have to utilize something which is where we might have to invest time and effort to research something new. Maybe some of the issues, solutions are readily available. We can maybe we can connect with other industries, other partners and we can find solution. In fact, in data steel, we have adopted our strategy exactly in similar light in this line only. So we have adopted technologies where some of the things they are ready to be used directly, maybe from some of the other adjacent industry. And there are certain issues where we do not find a ready-made solution. So there actually we have started our own research and development. And again, we are doing it collaboratively with academia and industry. So I think that's a way forward for our kind of industry. Thank you. That's a really great perspective. And what you bring up here is a good point and kind of the purpose of this workshop is to discuss kind of how to make these big steps forward of these transitional technologies and changes where we do have to introduce risk that is traditionally hard to do. So Eric, you brought up very effectively this concern of the trade-off, the bottom line how to prevent even 10 cents per ton of increase in cost. And in steel, I know that there's a similar type of a picture. I don't have the numbers off hand. So what do you, and I'll ask this to the room at large, what do you see as strategies that really are needed here to be able to enable this type of transition, this type of taking a risk in these massive, massive industries that are so ingrained and have such large infrastructures? I would just comment from my side. I think one of the things is at the funding stage, the research and the research funding stage, the investment stage, et cetera, for new technologies, the potential costs of those technologies should be one of the primary determining factors of that because there's a huge amount of things that are funded at the research level or even funded for pilot projects that are just obviously not going to be economically viable. And I think it needs to play a more central role in decision-making for looking at early stage technologies. In some cases, you effectively can't really understand are they gonna be, so there's some gray area and large gray area there, but there's in some cases where you absolutely know it's gonna be more expensive. And I think the industry doesn't need to try to avoid that, it just will. It just will not implement anything that's going to increase its variable cost. And then I think on the policy side, carbon tax. If there's no carbon tax, there's absolutely no way to get a whole class of emerging technologies. And you can see in Europe, there's a lot more innovation coming from the fact that the EUETS applies to the cement industry for 15 or 20 years now. So yeah, those are my quick comments. Let me add to Eric, in the sector, for any commodity sector, not just in here, the customer does not care about the technology. They care about the specification. And once it's made, the specification is the cost structure. So as was mentioned before, so there will be no silver bullet everywhere, depending on where it is, different solution will take place. So what is needed is a good regulatory framework which looks at the total cost of ownership. It's not just a cost of ownership of a particular segment or something, but what is my total cost of ownership? If there's a carbon tax, so people will look at and give an example of hydrogen, for a customer, they don't care if it's blue, green, white, black. Does it meet the low carbon standard specification? Do I have it on specs and what is the cost? So that is what is needed, is that framework to define that? And then people can look at the total cost of ownership. Viara, I have a question, a follow-up question for Eric. Clearly we are talking about costs. And I'm wondering whether sometimes costals should also be considered or look at more holistically and what I mean is the following. The cost that, for example, Eric showed, refers to cement and that does not include, for example, the cost of steel that comes later when a concrete is made. And so sometimes I feel and clearly I'm not, it's not my expertise that things are, we are comparing April with oranges because the cost refers only to cement and not the whole composite, so including steel. And the second question that I have, how is usually durability factored in? Because clearly the more we have to replace concrete, the more cost it will have. Yeah, thanks, Tiziana. I think that's, I mean, those are excellent questions. On the first one, I limited my, I actually removed a lot of the stuff about concrete in my talk today because I understood we were talking about cement and electrification. I think you just have to look at who are the players in the industry and what is the cost structure of each player in the industry and they make decisions on that basis. And in cement, these are the costs, that's the reflection. They don't care about steel at all. No one cares about steel in cement unless they're also producing steel. They just care about selling cement. Now, if you look at concrete companies, they also don't care about steel. Who cares about steel? The, I guess the project owners that are designing a structure that's going to be a structural element in a building, they who care about steel. And actually the architects may or may not care about steel. The suppliers of those placing service, they may or may not care about steel. The only person who's really gonna care about that is who's paying the bill for the whole building. And that's extremely hard because there's this huge value chain of people and that person who's paying for the building doesn't have any technical expertise a lot of the time on this stuff. So you have to get architects, owners, engineers, owners together and talk like, oh, how do we get a new generation of material that's gonna replace the steel? And there's use of fibers and things like that. But I agree, that's a complex question. But I think each industry you have to operate within the logic of that. If you're gonna try to decarbonize cement, they don't care about steel. If you're gonna try to decarbonize concrete, they also really don't care about steel. If you're gonna try to decarbonize buildings, they might whoever's paying for that building is gonna care if you can do that or not. And whoever's responding for the carbon footprint. So that's on the first question. Sorry, remind me the second question was? The second question was more about how durability and visibility is factored in. Badly, difficult. That's probably one of the most problematic issues for new material developments into the industry because there are a lot of things that you could look at resistance to chemical attack or I don't know. There's a whole bunch of tasks you could perform in a lab but like a lot of the time, the only test that people will accept on durability is like there's a building, it's been there for 30 years. And that really makes it difficult. And I think you can do accelerated testing and cycling it and stuff like that. But a lot of it's very difficult to convince regulatory committees and insurance companies and all those about the long-term durability material if you haven't had it for at least a decade or two somewhere in some environment. And I think that really slows down the pace of innovation but it's because it's related to public safety and massive potential liabilities. Imagine you build a bridge with a material and then it collapses at any point inside of the liabilities and the public safety issues around that are enormous. But I would say that's one of the most difficult issues. And I think it's Larry Sutter in academia who talks really a lot about durability and has some interesting thinking about that. He sits on a lot of the ASM committees. But yeah, if you're going to more insightful or nuanced view on how people deal with that or what they're working on for emerging tests for long-term durability or how the industry perceives that, I definitely recommend to talk with him. But I think it's a difficult and poorly solved issue currently. That's very interesting. And I think an interesting point to be made actually from the steel side as well because I would say there's definitely feelings of these are two separate beasts. We shouldn't consider each other as we're doing this but there are inputs from steel making to cement making and vice versa, right? So I think seeing the other side of this picture is also of interest. Chris, you had mentioned this from the perspective of the changes that have happened in the steel making industry. Where do you see that the challenges are hindered in this field for the next step in the transformation here? Sadly, exactly as the other said, it's cost. It's going to be more expensive. If it wasn't going to be more expensive, we would be doing this already. Right now there isn't a cost to emitting carbon from electric furnaces in the US. So we burn an awful lot of carbon in these furnaces. It helps you to make high quality steel but probably we do it a little bit excessively but that's okay in terms of the quality and the cost at which it can be produced. And some of the estimates of the costs are really quite daunting. So if you were to directly exchange natural gas to make direct reduced iron with green hydrogen at $4 per kilogram, that'll add $200 and something dollars per ton of steel. So that's a huge increase which if there's another cheaper, more carbon intensive source of steel available, it'll be very hard to persuade end users not to use that unless there are very clear carbon taxes. So this is this complex interplay of factors, all of which must work simultaneously. So cost is definitely, I think the biggest one. I mean, there are technical challenges but we've been using hydrogen in one way or another in this industry for a long time, probably not as pure hydrogen, typically as hydrogen mixed with carbon monoxide but pretty high concentrations of hydrogen. So there are some remaining technical issues for which I'm grateful being an academic who researches these things but frankly, I don't think those are the biggest issues. What are strategies that you see to de-risk that industry, to kind of de-risk those types of investments? Yeah, so Solvid is to show pilot installations of this. So there is that pilot project underway in Sweden which puts these elements together of having a large scale electrolyzer, direct reduced iron plant and electric furnace to melt down the product. And I would be very surprised if it doesn't work but I mean, that does provide some faith that it can work and similarly, Posco is doing that with their fluidized bed type process. So that will help. I think the industry though, accepts that it's probably technically feasible but not proven at scale yet. So yeah, I think that'll help at least a little bit. So I think this question of how do you prove something at scale that is a new technology in time for to be able to prevent some of the biggest catastrophes in climate change is a big and very important question on all of our minds right now. So I think I'm gonna open this question up to the entire panel of where do you see that this concept of de-risking so that we can demonstrate a scalability in these types of technologies that are new and considered untested in time. Pula Keshe, I see you also went off mute. Do you wanna comment on this? This is where the incumbent plays a massive role because for the scale needed on both the supply chain and also the risk and the technical understanding that's where incumbent like Tata Steel or other steel companies on the cement companies like they need to play a role and they are playing the role. So that's where yesterday people talked about cooperation that's the cooperation needed between early stage academic research incubators. Those are taking the technical risk like this is like us along with the incumbent playing a role. Another point I want to highlight and please mention we are talking about cost but we have to think about the total cost of ownership. So let's say there is a carbon tax of $50 to $100. So for those who are producing you need to compare the total tax in the system and the total cost. So a lot of the things we are talking today does not compete with cost with the existing cost of production but not necessarily with the regulations or other specification coming in with a total cost of production and that's one way of looking at it which I think will help the industry. Thank you. Very well said. So we have a couple of minutes left. Marie Ganchu, do you wanna comment on this? Yeah, so maybe I tend to agree with what Pulakesh just now mentioned but for any untested technology if you have to establish that it also has a, I mean it does take a lot of time. So I can cite one example from data scenes. So like our European unit they already started developing an alternate island making process. I think Professor Pistorius and many of the panel members who will be knowing about it. So it is called Heiserna. So it's actually a collaboration between erstwhile tourist in plant with your team of Australia. So they demonstrated the process and then they upscale the process sometime in 2010 and they created a pilot plant in or I would name plant still manufacturing facility and in fact they demonstrated that this new process is capable of reducing the CO2 emission by 50% without even using carbon capture. But still it is not commercialized. I mean, even if we have demonstrated it at that level so even we need to demonstrate it at even higher level and plants are on to set up another full scale plant somewhere in India. So sometimes this lifetime of developing a technology is also something which one has to be mindful about. So I think that is one point I thought I would add from the industry side. Thank you. Eric, did you want to comment on this as well? I think it's a very relevant question on the policy side. I really think yeah, somehow looking for how to support the demand side on the government, how to support the demand side and how to level the playing field on the government side is probably the best strategy to say like a lot of what's happening currently in the US on procurement of low carbon materials. I think it's great because it allows you to have markets for that. And I think what's happening in the EU on taxing the emissions of CO2 or taxing it or you're grading a cap and trade scheme or in California there's a lot of public policy on putting some sorts of schemes. So things that produce a lot of CO2 are less economically viable. I think that's great. Where I think there's a lot of issues and I guess a lot of people would disagree with me but beyond just the basic research funding where the government starts to get involved in like backing particular technologies. I think a lot of errors can be made there and a lot of errors can be made in saying this is the technology that's gonna bring us forward because the way the industry can present those or the technologists can present those are oftentimes to tell the story that the government wants to hear on that. And I think the real innovation will have the real support from the public policy and the government side is create a level playing field in which if you emit a ton of CO2 you pay something for that or you have a penalty for that and then let the innovators in the industry figure out that stack of technologies to respond to the actual market and make sure also on the demand side you're gonna someone's gonna purchase low carbon cement and make sure the CO2 is somehow having a cost. That's where I see the best role of government. Okay, there's some role in early stage R&D or in funding some stuff but where you start to have fully or mostly government funded pilots. Oftentimes it's just someone will say, hey, it'd be nice to do a pilot with this technology and they'll make whatever paperwork that the government needs to see for that. So anyway, it's a problem for, it's not that that has no role. It's just a problem that I see for public policy makers to really get through the smoking mirrors around those applications and understand which technology. So I see it's better, if there's a choice to be on the side of creating the level play of field and creating the demand. Thank you. So we'll turn now to some questions from the audience. I see that Dhruv Arora asked a question. Is there a thinking about market driven innovation where customers who are willing for the lower carbon footprint to cement to be able to pay for it as well? A market innovation where customers who want lower carbon cement can pay for it. I mean, I guess they just choose to do that. So I mean, the government has chosen to do that with the GSO just like two weeks ago, made an announcement, we're gonna procure a low carbon cement. New York state has chosen to do that in some respect. And they have public procurement but private companies can just do that if they want. And actually Amazon or Microsoft or companies like that do do that. But I don't know what further market innovation is needed. Looking on the public policy and procurement side, there are innovations on that to say, how do we measure this and how do we procure it? But on the private company side, it's a little bit more difficult. It's just, hey, does the market demand from them to do that? So I don't know, putting regulations on embodied carbon in buildings and giving building permits easier for lower carbon buildings or things like that, that could tend to stimulate the private demand too. But it's hard because the private markets are not regulated, it's hard to figure out what innovation is needed there. It just operates on economic principles. What I can add is something similar is definitely happening in the steel market as well. So Nucor has branded some of their steel to be essentially zero carbon at least as far as scope one and scope two emissions are concerned. So they are a big buyer of clean electricity and scrap recycling. So they're seeing that as an advantage in the market. The other advantage is it sells at, I think exactly the same price as any other steel, except it's zero carbon as well. So that's of course the advantage they have in being a recycler. So I think there are various ventures like that that will come up but that will get us some of the way but of course the really big shift to making the whole industry zero carbon, that will require a lot more and will imply higher costs. Thank you. So there's a couple of... Can I also add something after the story? That is especially in steel industry, there is an independent third party certification program for responsible steel. So I mean, a lot of steel plans are actually going for this certification which is called as responsible steel. So they are basically a nonprofit organization and they are coming up with sustainability performance standards and they give certification to leading steel plan. So like Tata Steel is also one of the responsible steel certified. Arcelor Metal is one of the responsible steel certified companies. So all these big company, they're going for certification. It's interesting to see that because it's also higher up the supply chain, right? So it's not something that a typical consumer would be purchasing. And it's interesting to see that that's effective. So we also got another question in the chat. Chastity Lee asks what ballpark amount or cost of carbon tax would be sufficient to make the economics more in favor of adopting existing green technology now? I can answer. I mean, in cement, it depends on... So there's a whole bunch of... Like there's a cost curve. So if you have five or $10 or $20 a ton, you can already do some stuff depending on how you apply that tax. To get a broad like complete decarbonization of the cement industry and carbon capture because you have a billion plus tons of just process emissions, that's gonna be at least $7,500 a ton to be able to do that. And some people would argue it's more. I just think that the cost of carbon capture is coming down and it will also depend on the government providing some regulation infrastructure for carbon transportation and storage. So yeah, if you have the carbon transportation and storage somehow taken care of by the government even at $50, $60 a ton, you could do a lot of that stuff. If you don't, then it's difficult to do even at a higher amount, at least my read in cement. But you can already do stuff at $20, $30 a ton for sure. Thank you. Chris, do you have a comment on that for steel? Yeah, I think it's a little bit similar for steel. Going whole scale from natural gas for DRI to hydrogen implies a crazy number like $300 per ton of CO2, which presumably we won't get to, I hope. But yeah, there are some interim measures that will spur innovations in how electric furnaces are run at the sort of $20, $30 level that will already help. Thank you. So this was a great discussion. We're running out of time now, or well, we're out of time now. So I'd like to thank all of our speakers for a wonderful discussion. I think that we discussed some really interesting ideas about where the industry is, both in cement and in steel and a really interesting picture of the role that policy and the incumbents and the new innovators need to take in being able to evaluate both the cost structure, cost of ownership, versus the cost of the process to be able to kind of shift towards these newer directions or decarbonized directions. So with that, I will thank all of our speakers again and turn it back to Richard to continue on this program. Thank you, Leora, and thank you to all the panelists. Had actually two great panels today and I hope you've had all of you have found today's meeting informative and really inspiring.