Literally unearthing a climate solution with Cody Finke of Brimstone

When it comes to carbon emissions, there’s a major culprit you might not have heard about: cement. The production of cement emits almost as much carbon dioxide as cars do - but Brimstone CEO and co-founder Cody Finke says they’ve found a way to change that. This week on How I Built This Lab, Cody explains where all that carbon dioxide is coming from, and how swapping out a key ingredient in the production of cement could take it from carbon-intensive … to carbon-negative. This episode was produced by Alex Cheng with music by Ramtin Arablouei. It was edited by John Isabella with research help from J. C. Howard. Our audio engineer was Patrick Murray. You can follow HIBT on Twitter https://twitter.com/HowIBuiltThis & Instagram https://www.instagram.com/howibuiltthis, and email us at [email protected]. See Privacy Policy at https://art19.com/privacy and California Privacy Notice at https://art19.com/privacy#do-not-sell-my-info.

Speaker names marked ? are inferred from speaking time and the show’s known hosts — they are not voice-verified.

• 0:00Guy Raz?

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• 0:46Guy Raz?

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• 1:32Guy Raz?

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• 2:16Guy Raz?

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• 3:00Guy Raz?

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• 3:45Guy Raz?

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• 4:27Guy Raz?

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• 5:11Guy Raz?

  Hello and welcome to How I Built This Lab. I'm Guy Raz. So when it comes to carbon emissions, there are the usual suspects we hear about all the time: fossil fuels, livestock, transportation. But there are other sources of carbon emissions that are less flashy but just as impactful on our climate, including a material you might be standing on right now, which is cement. Yes, cement. We use it to glue together just about everything we build. But the production of cement worldwide actually emits almost as much carbon as cars do. The majority of that carbon comes from one of the main ingredients in cement, which is limestone. To make cement, you basically cook limestone at high temperatures.

• 5:56Guy Raz?

  But limestone is actually a carbon sink. It contains a lot of carbon. And when you heat it up to make cement, that carbon is released into the atmosphere. Well, my guest today says there's another way to make this critical building material. Cody Finke discovered the concrete problem when he was studying chemistry at Caltech. He realized there was a different rock that could replace limestone in concrete production. It's a rock that really doesn't emit any carbon when heated. And so Cody co-founded a company called Brimstone that could become the future of construction materials. Cody spent his time at Caltech looking for a climate issue to solve, and he started with solar-powered toilets.

• 6:37Speaker 01

  I wanted to work on problems that were massively underworked on, had environmental and social implications, and wastewater treatment for applications in low-income countries was an obvious choice. And that was something that one of the labs at Caltech was working on, so I enthusiastically joined that lab. I did some travel in India and seen that firsthand and how it impacted people. And the idea was we'd build a system that didn't need a sewer, didn't need a grid, was just fully independent and treated wastewater on-site. But through that project, I also learned that deploying these sort of do-good technologies

• 7:18Speaker 01

  is not trivial, because people don't just buy them and install them out of the goodness of their heart, or at least not enough. There needs to be a compelling economic case. And after three or four years of working on that solar-powered toilet system, I realized that there just wasn't a compelling economic case, and therefore, no matter how well the technology worked, it was not going to make an impact.

• 7:39Guy Raz?

  This couldn't be a sustainable business, as you kind of got to that conclusion.

• 7:44Speaker 01

  That's right. And if it's not a sustainable business... Then it's also not going to have the environmental impact I wanted to have because it just isn't going to achieve the scale.

• 7:53Guy Raz?

  This project that you worked on, I mean, it won an award from the Bill and Melinda Gates Foundation. So, I mean, it was no joke. I mean, it was just a serious, and essentially it was a, it worked, right? I mean, what you put together worked.

• 8:05Speaker 01

  Yeah, I spent a long time, a lot of time in India, sort of wallowing around in human wastewater as I was working on that project. And yeah, it worked.

• 8:12Guy Raz?

  So you, you ended up continuing your studies at Caltech and you did your PhD there.

• 8:17Speaker 01

  Yeah.

• 8:17Guy Raz?

  And I guess while you were there, you, after that project, you decided to, to tackle another project around water electrolysis. Can you tell me a little bit about what that project was?

• 8:29Speaker 01

  Yeah. So after this solar powered toilet situation, I was looking around for what else to do. And a lot of folks at Caltech were working on splitting water in order to replace fossil fuels. And the idea was we could use clean renewable electricity, split water into hydrogen and oxygen, and then use that hydrogen as a fuel to fuel everything we do today, and we wouldn't have to use any fossil fuels. And the scale of that solution was really compelling to me. That's 70% of greenhouse gas emissions. But I realized that the technology had been around for over 100 years. And we don't make hydrogen by splitting water today. We make hydrogen a different way from a fossil fuel,

• 9:10Speaker 01

  actually. And we do that because it's the lowest cost way to make hydrogen. And I didn't see a route for hydrogen production to become lower cost than the production from fossil fuels. And therefore, ultimately, I didn't see a chance for there to be a big impact. So I ultimately stopped working on that project, too.

• 9:30Guy Raz?

  But clearly, you were thinking of a project that you could get behind. I guess the question you were asking yourself is what are the things that create carbon emissions? It's interesting because it's a similar question that like Pat Brown asked himself before he started Impossible Foods. And his, his realization was, you know, raising livestock, right? Clearing forests to create grazing spaces and raising livestock for, for human consumption, you know, accounts for 15% of global carbon emissions. Presumably, you're asking yourself the same questions. What are the things that cause the most pollution that I might be able to fix? So what kinds of industries or?

• 10:10Guy Raz?

  Materials were you looking at?

• 10:12Speaker 01

  Yeah, so I found this really interesting graph from the IPCC report, I think it was.

• 10:19Guy Raz?

  This is the, obviously, the UN Panel on Climate Change.

• 10:22Speaker 01

  Exactly, the Intergovernmental Panel on Climate Change, the IPCC. And this graph kind of broke down emissions by sector. What really attracted me were the chemistry problems, because I'm a chemist. And there are several categories that have these things called process emissions, where the chemical reaction we use to make the thing actually emits a greenhouse gas. It's not just energy, it's the chemical reaction. And the four big ones are production of steel, production of aluminum, production of hydrogen, actually, and then production of cement. This is a huge problem. I then looked at the amount of funding, right?

• 11:03Speaker 01

  And one metric that was really interesting to me was the dollars invested in decarbonizing the product per ton of greenhouse gas emissions. And I couldn't really find anything lower than cement.

• 11:14Guy Raz?

  It's interesting, because I guess concrete and cement are, they're slightly different.

• 11:18Speaker 01

  That's right.

• 11:18Guy Raz?

  Concrete is a product that comes from cement.

• 11:21Speaker 01

  That's right.

• 11:21Guy Raz?

  But together, they're, they account for like 8% I read of global CO2 emissions, which is the same amount as all the cars around the world.

• 11:28Speaker 01

  Yeah, just about the same, yeah. And just to clarify, the cement and concrete, right? Concrete is the building material and cement is the binder, is the glue.

• 11:36Guy Raz?

  Yeah.

• 11:37Speaker 01

  And about 90% of the emissions come from cement.

• 11:40Guy Raz?

  Yeah, and I mean, it's amazing, because like cement is critical. Like, we need this building material to build on planet Earth. And so it seems like a kind of intractable problem, right? It's not like, I mean, even fossil fuels, there's a backup, right? With renewables, but with cement, there's no easy backup. I mean, this is what you're sort of discovering, I guess, in 2015, 2016, when you're looking into it.

• 12:05Speaker 01

  That's right. I actually, I really liked that, because it made the solution space really simple. And I think you need to simplify the solution space in order for a human brain to be able to think about it creatively. So yeah, that was one of the things that attracted to me, how simple the solution space was.

• 12:22Guy Raz?

  All right, so let's break down the problem. Why does cement create so much carbon emissions?

• 12:28Speaker 01

  Yeah, so the emissions associated with cement production come from two places. The first is you need to burn a lot of fuel, because you need to use a lot of energy. To make cement, and that's about 40% of the emissions in cement production.

• 12:43Guy Raz?

  To heat it up very hot.

• 12:45Speaker 01

  Oh, yeah, you have to do a chemical transformation and that chemical reaction requires heat or requires energy.

• 12:50Guy Raz?

  And by the way, the the main component is limestone?

• 12:53Speaker 01

  That's right. So that's where the majority of the emissions come from. So in order to make cement, you need a source of calcium. And the current way we make cement, that source of calcium is limestone.

• 13:04Guy Raz?

  Because why?

• 13:05Speaker 01

  Because at the time that cement was invented, it was the lowest cost source of calcium.

• 13:11Guy Raz?

  And this is in like the 1700s, I think.

• 13:13Speaker 01

  Different people have different timelines, but yes, like the first polycalcium silicate cement was in the 1700s.

• 13:20Guy Raz?

  Right. And so limestone was used because it was readily available and relatively cheap. And now that's just the standard.

• 13:27Speaker 01

  That's right. And in order to get the calcium out of the limestone, you use all that heat to do a chemical transformation, which removes the CO2 from the limestone. And if you use heat, all that CO2 will go up into the atmosphere and you'll be left with the calcium that you can then turn into Portland cement.

• 13:44Guy Raz?

  Wow. So basically, it's like a double whammy. You're using heat to heat it up and the heat, just that energy alone is emitting carbon. But then there's also carbon dioxide in limestone. So when you heat the limestone to break it down, you're you're releasing all that carbon into the atmosphere.

• 14:01Speaker 01

  That's right. And the majority of the CO2 emissions from cement come from that chemistry for releasing the CO2 from the rock.

• 14:07Guy Raz?

  So limestone is a is a carbon sink, basically.

• 14:10Speaker 01

  That's right. Yeah. So in the global carbon cycle, an enormous amount of Earth's carbon is stored in limestone.

• 14:16Guy Raz?

  Wow. So this is, it's like you hear about the tundra, you know, the tundra that's defrosting in the Arctic, and that's a carbon sink. And obviously, when it defrosts, it releases carbon. So this is a deliberate process to make cement, but it's essentially just releasing all this carbon, and which which is a huge problem.

• 14:35Speaker 01

  That's right. Yeah, it's just another way that humans are perturbing the global carbon cycle. In a normal environmental carbon cycle, CO2 would be released from volcanoes and would react with calcium that's been dissolved in the ocean and precipitate limestone. And then that limestone would sit around forever, for several billion years, until it was subducted down to the earth's crust again and then decomposed under the earth and the CO2 was released through a volcano. And humans have, by digging up limestone and heating it up to volcano-type temperatures, we release that CO2 prematurely, which perturbs the carbon cycle, just like with fossil fuels.

• 15:12Guy Raz?

  Wow. All right. So when you came across this realization, I presumably you thought, this is the thing. Maybe this is the thing that I can, I can try and fix.

• 15:22Speaker 01

  Yeah, it's quite interesting. It had all the attributes, right? It was the giant problem. Basically, nobody was working on it. And it was tracked, seemed tractable to me because it was a chemistry problem. The chemistry problem was, most of CO2 emissions have nothing to do with energy. They have to do with the chemistry of making cement. So can I change the chemistry such that it doesn't make CO2 emissions?

• 15:43Guy Raz?

  We're going to take a quick break, but when we come back, Cody finds a solution to that chemistry problem right beneath his feet. Stay with us. I'm Guy Raz and you're listening to How I Built This Lab.

• 15:58Guy Raz?

  Hello, everyone. I've been working with Miro, that's M-I-R-O, over the last year to help me get a better sense of what you, our incredible listeners, are thinking. Miro has sponsored quite a few of our episodes, and it's just an amazing tool for collaboration and working with teams. If you haven't heard of it, Miro is this incredible online workspace. And I think it's super useful to try it out if you want to build something great with your team. Now, I want to talk about a part of Miro that many of you probably have never heard of before. It's called the Miroverse. Sometimes, starting work on an online visual workspace can feel overwhelming. But with Miroverse, you can select pre-made boards for pretty much any use case. It saves you the hassle of building from scratch.

• 16:43Guy Raz?

  And what's really cool is that a new template has just been added, this time from me. We partnered with the folks over at Miro to create a how to build a podcast Miroverse template to help kickstart your journey to making a podcast. So check it out and let me know what you think. Head on over to miro.com/hibt. That's M-I-R-O dot com slash H-I-B-T to check out our Miroverse template for yourself. Does your team want a website that looks and feels handcrafted but is still fast to ship? Well, Framer is built exactly for that. With Framer, you design on a visual canvas with responsive layouts, hosting, and a CMS built in.

• 17:27Guy Raz?

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• 18:12Guy Raz?

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• 18:57Guy Raz?

  work together, and that shift is already underway. That's why NetSuite wants to put a new expert-created business guide in your hands today. It's called Aligning for the Agentic Era: How AI is Changing Everyday Work. And right now, it's yours, absolutely free. Inside, you'll discover how AI could reshape work across your entire organization, and how to position your business to prosper from it. If your revenues are at least in the seven figures, get NetSuite's free business guide, Aligning for the Agentic Era: How AI is Changing Everyday Work, at netsuite.com/built. The guide is free to you at netsuite.com/built. netsuite.com/built.

• 19:42Guy Raz?

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• 20:26Guy Raz?

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• 20:41Speaker 02

  Hi, my name is Jesus Rubalcaba. I'm the owner of Paper Taco's greeting cards. And my favorite episode of How I Built This is May of Chesapeake Bay Candles. I could really relate to her, especially when she talks about going to trade shows and people just passing her by, trying to reach out to buyers of several department stores and hoping to get an order, scaling, trying to create manufacturing. And all the struggles that she faced there are things that I'm currently trying to overcome. So I really resonate with her story and really appreciate that you all shared it with us.

• 21:13Guy Raz?

  If you want to share your favorite episode of How I Built This, record a short voice memo on your phone telling us your name, where you're from, what your favorite episode is, and why, a lot like the voice memo you just heard. And email it to us at [email protected] and we'll share your favorites right here in the ad breaks in future episodes. And thanks so much. We love you guys. You're the best. And now, back to the show. Welcome back to How I Built This Lab. I'm Guy Raz. My guest today is Cody Finke, co-founder and CEO of Brimstone. His company has found a way to produce cement that eliminates carbon emissions, which could

• 21:58Guy Raz?

  have a big impact on our climate. But back in the late 2010s, Cody had just started exploring the idea at Caltech.

• 22:07Speaker 01

  We looked around at the existing solutions and we saw that most folks were working on making a novel material, not Portland cement, which makes a lot of sense because if you make a novel material, then you don't have to use limestone and therefore you don't have to make the CO2.

• 22:23Guy Raz?

  And Portland cement, we should mention, is like the most common type of cement used around the world. It's probably in your home or on your sidewalk. It's basically just the term for cement. It's not from Portland, Oregon, or Portland, England. It's just, that's what it's called.

• 22:39Speaker 01

  That's right.

• 22:40Guy Raz?

  All right. So you initially thought, okay, let's just take the same materials, the limestone. I think it's like aluminum and there are a few other components that go into making cement. Let's use these components, but just change the chemistry and see what happens.

• 22:56Speaker 01

  Yeah, or maybe even use some different components. Maybe we could just make a different material that still works like Portland cement, but is not Portland cement. And one of my early mentors was one of the women at Kel-Tec who was leading the entrepreneurship program. Her name is Stephanie Anczynski. And she was like, well, you should go talk to customers. And we learned that it'd be very hard to enter the market with a novel cement.

• 23:20Guy Raz?

  And when you say a novel cement, a cement that was not Portland cement?

• 23:23Speaker 01

  That's right. Yeah. And the reason for that was is basically it's just risk. If you're a structural engineer, or a builder, or a concrete provider, then you want your material insured in case there's a problem with it. And you also don't want construction delays. You want to make sure that everyone who's building the building knows how to work with the material.

• 23:42Guy Raz?

  Yeah.

• 23:43Speaker 01

  Because both structural failures and construction delays are way more expensive than the cement, like 10 to 100 times more expensive. And because of those things, we basically found that no one that we talked to was excited about using a novel material. It seemed just too structurally hard. And that was actually the big aha moment, which really simplified the problem. We realized that, okay, if we want rapid adoption, which is important for climate, but we want to solve the problem quickly, then you need to produce ordinary Portland cement.

• 24:15Guy Raz?

  Yeah.

• 24:16Speaker 01

  So we said, okay, great. Where's all the calcium in the world? And we found that the calcium was in three places. There's limestone, which cement is made out of today. There's gypsum, which cement has been made out of in the past. And then there's calcium silicate, which no one had ever made cement out of.

• 24:34Guy Raz?

  Huh. And from what I understand, these calcium silicate rocks are abundant, right? Like, I think you're talking about rocks made out of silicate materials that also have calcium in them. So I guess like basalt would be an example?

• 24:47Speaker 01

  Yeah.

• 24:48Guy Raz?

  Well, but I mean, presumably, there's a reason why limestone is still used. I mean, I know that maybe an answer could be, well, it's just been tradition, or it's just what people are used to, but there must be some... Reason is it stronger, is it cheaper to get to like, why? If these other natural resources exist that have the necessary components to make cement, why weren't they used in the past?

• 25:16Speaker 01

  Yeah, the thing that we have to realize is that the production of Portland cement has been around for at least 150 years.

• 25:24Guy Raz?

  Right.

• 25:25Speaker 01

  And the reality is, is the production of commodity chemicals, the like production method tends to change every 50 or 100 years. You know, it takes a long time. The global economy really has to change in order to make a new system more economical.

• 25:38Guy Raz?

  Right.

• 25:38Speaker 01

  So for over a century, limestone was the most economical way to make cement. But there's been some massive structural changes in the economy that have made a pretty recent phenomena that we no longer think limestone is the most economical way to make cement. The current production of cement actually relies on the production of electricity and steel from coal. And both of those industries growth have slowed and that is leading to a domino effect where the price of cement has been rising. So why was cement made from limestone? Because it's the cheapest way, or it was. The economy has now changed over the last 150 years and it's, we believe that it's no longer the cheapest way.

• 26:17Guy Raz?

  So is it more expensive to make it from calcium silicate?

• 26:21Speaker 01

  In the modern economy, we think that will be lower cost at scale. And that's core to our philosophy because we don't think that the technology will scale globally if it's not lower cost. And if it doesn't scale globally, it doesn't have a big impact. And if it doesn't have a big impact, then I'm not interested.

• 26:36Guy Raz?

  So what about the strength of the end product? I mean, is it a, is it as good as Portland cement?

• 26:42Speaker 01

  So it is Portland cement.

• 26:44Guy Raz?

  It is?

• 26:44Speaker 01

  Yeah, it is Portland cement. So that's the key, the key thing, right? We don't think global adoption will happen if it's not Portland cement.

• 26:52Guy Raz?

  Right.

• 26:52Speaker 01

  Or at least it won't happen quickly.

• 26:54Guy Raz?

  All right. So you basically say calcium silicate, which is a type of rock that that's abundant. It's available around the world. It has all basically the same essential properties as limestone that, you know, make it a great material for making Portland cement. And essentially, it's not a carbon sink, right? Carbon is not stored inside of calcium silicate.

• 27:14Speaker 01

  That's right. So calcium silicate rocks, they don't have any CO2 in them.

• 27:18Guy Raz?

  So you, how does your process eliminate carbon emissions? I mean, when the rocks are heated, I understand they don't release carbon like limestone, but there still are emissions in the process, right?

• 27:32Speaker 01

  So there could be emissions in the process if you use a dirty fuel for producing the heat, right? Heat can be produced via clean electricity or fossil fuel or anything else. But the beauty of our process is that it actually can be substantially lower carbon or even carbon negative under a wide range of of energy sources, including the use of those dirtier fuels. And the reason that is, is because the calcium silicate rock, A, does not contain any CO2. So we eliminate 60% of the emissions just by using a different rock. And then B, it produces a magnesium-based waste product. And that magnesium-based waste product will passively sequester CO2, just sitting on the ground and will react with CO2 in the air to permanently sequester CO2.

• 28:14Guy Raz?

  So the by, so when you, essentially what you're saying is when you make the cement, the byproduct of it actually sequesters carbon in this magnesium byproduct, which you can then do what with? You bury it underground? What do you do with it?

• 28:27Speaker 01

  Yes, there's a lot of things you could do with it. Basically, the simplest thing to do with it is just put it in our tailings pile and then backfill our quarry with it at end of life.

• 28:35Guy Raz?

  So when you've got an empty quarry, oftentimes it could get filled up with water, right? But you would just, you just fill it up with this material?

• 28:42Speaker 01

  Yeah.

• 28:42Guy Raz?

  And there's no like risk of it leaching or anything? It's just basically a carbon store?

• 28:47Speaker 01

  That's right. This is like, this is a normal rock.

• 28:50Guy Raz?

  Essentially, if you can do this at scale, what you're saying is not only can you eliminate carbon emissions from the production of cement, but you can actually remove

• 29:01Guy Raz?

  Carbon from the atmosphere by sequestering it in this byproduct that comes out of the process is magnesium.

• 29:08Speaker 01

  That's right. And magnesium carbonate is baby powder. So we basically make synthetic baby powder passively that removes CO2.

• 29:17Guy Raz?

  So, all right, so you founded a business, co-founded a business with, I think, with a partner that you'd worked on at graduate school on this water project.

• 29:26Speaker 01

  That's right.

• 29:26Guy Raz?

  Hugo Leandry, I think, is his name.

• 29:29Speaker 01

  Yes, that's right.

• 29:30Guy Raz?

  And together, you've basically founded the company called Brimstone.

• 29:34Speaker 01

  Yes.

• 29:35Guy Raz?

  And the idea of the company is to what? Is to become a cement company, like, you know, some of these huge, massive legacy cement companies, many of them are in China and Mexico, there are some in the United States. Is that the idea here?

• 29:49Speaker 01

  Yes, the idea is to develop the processes to make the building materials of the future in a more economically appropriate, and most importantly to us, zero carbon way. And cement is the material that we are starting with because it's the most obvious output of our process. But ultimately, our process actually produces aluminum and iron. So we hope to really decarbonize all of the major emissions producing building materials in a more efficient way.

• 30:20Guy Raz?

  We're going to take another short break, but when we come back, Cody looks to the future of Brimstone and faces a big, expensive challenge: scaling. Stay with us. You're listening to How I Built This Lab.

• 30:37Speaker 03

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• 32:13Guy Raz?

  Welcome back to How I Built This Lab. I'm Guy Raz. Here's more from my conversation with Cody Finke, co-founder and CEO of Brimstone. They've developed a carbon negative process for manufacturing cement, which could have a massive impact in reducing carbon emissions around the world. I know you've started to raise a lot of money. You've raised over $60 million. Tell me how far along you are in proving that this, this works.

• 32:39Speaker 01

  Yeah, so just this last July, we got a third party certification that we, the cement that we made passed the existing standard for ordinary Portland cement, showing that it's chemically and physically identical to the conventionally produced product. So we have now developed a process that is the third ever process to make ordinary Portland cement.

• 32:58Guy Raz?

  Wow.

• 32:58Speaker 01

  And now we're working on scaling up to pilot scale version of that process that is optimized such that we are confident it will be lower cost at scale.

• 33:07Guy Raz?

  So right now, I think you're based in Oakland.

• 33:10Speaker 01

  That's right.

• 33:10Guy Raz?

  And I think you might have another facility in Idaho. And so I guess in terms of your business model, because obviously you have a mission, but you're also a business with investors.

• 33:20Speaker 01

  That's right.

• 33:21Guy Raz?

  I mean, I know, for example, here in California, where I live and where you're based, I think by, maybe by 2035, I think the cement sector in California has to.

• 33:32Guy Raz?

  Has to achieve emissions 40% below baseline levels, right?

• 33:37Speaker 01

  That's right.

• 33:38Guy Raz?

  So that's significant. And then by 2045, it has to be net zero.

• 33:42Speaker 01

  That's right.

• 33:43Guy Raz?

  So that's good for a business like yours because developers in California will have to use your product. But that being said, what's to prevent CEMEX, which is a Mexican multinational, or Alamo, which is a big US-based company, or Cal Portland, another US-based cement company, from just doing the same thing? Is your process so hard to replicate, or is it patented, or what?

• 34:07Speaker 01

  Yeah, so the process is patented, and the utilization of this rock to produce Portland cement is also patented. So another company would need to license or joint venture with us in order to make cement via this process.

• 34:20Guy Raz?

  Wow. So essentially, what you're saying is unless they can come up with a different method, this is going to be the standard way to make Portland cement, at least in places like California and other countries with stricter laws, in the next 10 to 20 years?

• 34:35Speaker 01

  That's right. And there are no other major sources of calcium besides these silicate rocks. So the other two are limestone and gypsum. Those produce CO2 or sulfuric acid as byproducts. So this is the beauty of our product.

• 34:48Guy Raz?

  So tell me about conversations you are having, if at all, with some of these legacy, big legacy cement manufacturers, these massive companies that produce cement?

• 34:58Speaker 01

  Yeah, so we are trying to understand the right way to work with these companies. We've had many, many conversations with them. And basically, we've kind of decided that the right time to work together is when we have a process working at scale. If we were to work together earlier, then we would potentially jeopardize our intellectual property, which is the only thing that, basically, how Brimstone maintains its investability is by keeping its intellectual property secure. But once we have the process at scale and we're at cost parity or better, then we're basically eager to joint venture or license to these existing cement companies so that we can get the process out into the world as fast as possible and decarbonize cement as much as possible and as fast as possible.

• 35:44Guy Raz?

  So sort of walk me through the next five years. I mean, presumably, it's going to be a while before you guys are bringing in revenue.

• 35:52Speaker 01

  That's right, yeah. So. Next five years, what we'll be working on is scaling up the process. All right, so the next step is building a pilot plant and that pilot plant, we're being very careful to build it so it actually, it actually represents a plant that would be lower cost at scale. And then from there, we will work on building our first commercial plant. You know, a commercial cement plant that's been built 3,000 times before, it takes two or three years to build. So in the next five years, we will be working on building a first commercial plant. I think it's probably unlikely that it's, you know, fully operational.

• 36:23Guy Raz?

  Within five years?

• 36:25Speaker 01

  Yeah.

• 36:26Guy Raz?

  And who do you think your initial customers will be? Like, a lot of these huge construction companies are, probably have massive contracts with massive cement manufacturers. So what do you think your approach is going to be?

• 36:39Speaker 01

  So it's a pretty complex market where normally a real estate developer will put out a request for proposal for a building and then someone will answer that request for proposal typically an architecture firm or engineering firm or both. And they will designate a builder or a general contractor and that general contractor will then buy concrete from a concrete company. And in order to make the concrete, that concrete company buys cement from a cement company. And usually the cement company and concrete company are the same parent company. So the only companies that ever buy cement are concrete companies, which are typically owned by cement companies. But the folks that ultimately pay for it are like two or three steps down the value chain, right? They're the real estate developers. So we see as our early customers, like real estate developers that are highly motivated

• 37:23Speaker 01

  to decarbonize because the, you know, the first plants, the cement is quite likely to be higher cost than conventionally produced cement. So you need some environmental motivation. Later, once we're at scale and potentially joint venturing with existing companies or, you know, building our own plants or licensing and we're not more expensive, right? We're cost parity are better, then the solution is obvious. It's, does a company want to buy something that's the same cost or lower that is also better for the environment? The answer is, it's obviously yes.

• 37:52Guy Raz?

  It seems like a no brainer, right? That if 8% of carbon emissions come from cement and the technology is there to do it and to do it cheaply. The challenge now is that existing cement factories are essentially at limestone quarries. So there is a cost associated with transforming this system. It's going to take a lot of money and time to do it.

• 38:15Speaker 01

  That's right. It's just like it's taking money and time to transform, you know, a coal and natural gas based electricity generation system into a renewable one. It'll be the same for the cement industry. Like, I don't think there's a silver bullet in anything, right? You know, there's going to be some, some cost to doing that and that's going to create some, some delays, unfortunately. Unless there's massive regulation at the global scale, which I think also is hard to imagine.

• 38:40Guy Raz?

  Just to put your business hat on again for a moment, to do this at scale, you're going to have to raise a lot more money, presumably.

• 38:46Speaker 01

  That's right.

• 38:47Guy Raz?

  I mean, hundreds of millions of dollars over time.

• 38:49Speaker 01

  So we want to see brimstone's technology deployed to produce the world's cement. So let's say a cement plant, a modern cement plant costs around a billion dollars. And there are 3,000 of them today. And there probably will be 5,000 by the end of the century because we will need to develop the rapidly developing world as well as transition to, you know, making new ways to make energy and everything else that's required for the green transition, which all of that takes cement. So at a billion dollars per plant and 5,000 plants, that's ultimately five trillion dollars. So it's a, it's quite a bit, but fundamentally will make money. So that's an attractive investment solution.

• 39:32Speaker 01

  So, once we can demonstrate the technology works and get down the cost curve by getting to scale, I don't think that financing will be an issue. I think that the challenging part is raising money for the early plants. But luckily, we live in a world where there are lots of people that are thinking about those problems. And so I, I think that the future is actually quite bright.

• 39:55Guy Raz?

  Awesome. Cody, thank you so much.

• 39:58Speaker 01

  Yeah, thanks, Guy.

• 40:00Guy Raz?

  That's Cody Finke, co-founder and CEO of Brimstone.

• 40:05Guy Raz?

  Hey, thanks so much for listening to the show this week. Please make sure to click the follow button on your podcast app so you never miss a new episode of the show. And as always, it's free. This episode was produced by Alex Cheng with editing by John Isabella and research help from J.C. Howard. Our music was composed by Ramtin Arablouei. Our audio engineer was Patrick Murray. Our production team at How I Built This includes Carla Estevez, Casey Herman, Chris Messina, Elaine Coats, Malia Agudelo, Neva Grant, Sam Paulson, and Carrie Thompson. I'm Guy Raz, and you've been listening to How I Built This Lab.