Literally unearthing a climate solution with Cody Finke of Brimstone

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1:58That's where a lot of businesses are with AI. Discover AI that can work seamlessly across your data and applications at ibm.com. The AI built for business, IBM. Hello and welcome to How I Built This Lab. I'm Guy Raz. So when it comes to carbon emissions, there are, you know, 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.

2:40but 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. 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.

3:21It'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. 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 don't travel in India and seen that firsthand and how it impacted people.

4:04And 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 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.

4:41This couldn't be a sustainable business as you kind of got to that conclusion. That's right. And if it's not a sustainable business, then it's also not going to have the environmental impact I want it to have, because it just isn't going to achieve the scale. 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 worked, right? I mean, what you put together worked. Yeah, I spent a lot of time in India sort of wallowing around in human wastewater as I was working on that project.

5:12And yeah, it worked. So you ended up continuing your studies at Caltech and you did your PhD there. Yeah. And I guess while you were there, after that project, you decided to tackle another project around water electrolysis. Can you tell me a little bit about what that project was? 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.

5:55And 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, 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. But clearly you were thinking of a project that you could get behind.

6:36I guess the question you're 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 realization was, you know, raising livestock, right? Clearing forests to create grazing spaces and raising livestock 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 materials were you looking at?

7:13Yeah. So I found this really interesting graph from the IPCC report, I think it was - This is obviously the UN panel on climate change. 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.

8:00This is a huge problem. I then looked at the amount of funding, right? 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. It's interesting because I guess concrete and cement, they're slightly different. That's right. Concrete is a product that comes from cement. That's right. But together, they account for like 8%, I read, of global CO2 emissions, which is the same amount as all the cars around the world. Yeah, just about the same. Yeah. Yeah. And just to clarify the cement and concrete, concrete is the building material and cement is the binder, the glue.

8:38And about 90 % of the emissions come from cement. Yeah. And I mean, it's amazing because cement is critical. We need this building material to build on planet Earth. And so it seems like a kind of intractable problem, right? But 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. 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.

9:20So yeah, that was one of the things that attracted to me, how simple the solution space was. All right. So let's break down the problem. Why does cement create so much carbon emissions? 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. To heat it up very hot. Yeah. You have to do a chemical transformation and that chemical reaction requires heat or requires energy. And by the way, the main component is limestone?

9:54That'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. Because why? Because at the time that cement was invented, it was the lowest cost source of calcium. And this is in like the 1700s, I think. Different people have different timelines, but yes, like the first polycalcium silicate cement was in the 1700s. Right. And so limestone was used because it was readily available and relatively cheap. And now that's just the standard. 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.

10:38And 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. 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 releasing all that carbon into the atmosphere. That's right. And the majority of the CO2 emissions from cement come from that chemistry for releasing the CO2 from the rock. So limestone is a carbon sink, basically.

11:12That's right. Yeah. So in the global carbon cycle, an enormous amount of Earth's carbon is stored in limestone. 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, which is a huge problem. 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.

11:51And 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, 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. 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 try and fix. Yeah, it's quite interesting. It had all the attributes, right?

12:27It was the giant problem. Basically, nobody was working on it. And it seemed tractable to me because it was a chemistry problem. The chemistry problem was most of the 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? 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.

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18:01Welcome 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 have a big impact on our climate. But back in the late 2010s, Cody had just started exploring the idea at Caltech. 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.

18:38And 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. That's right. 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. Yeah. Or maybe even use some different components.

19:13Maybe 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 Caltech who was leading the entrepreneurship program. Her name is Stephanie Jansinski. 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. And when you say a novel cement, a cement that was not Portland cement. 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.

19:51And you also don't want construction delays. You You want to make sure that everyone who's building the building knows how to work with the material. Yeah. Because both structural failures and construction delays are way more expensive than the cement. They're 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.

20:30So 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. And from what I understand, these calcium silicate rocks are abundant, right? I think you're talking about rocks made out of silicate materials that also have calcium in them. So I guess basalt would be an example. Yeah. Well, but I mean, presumably there's a reason why limestone is still used.

21:10I 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? Yeah. The thing that we have to realize is that the production of Portland cement has been around for at least 150 years. Right. And the reality is, is the production of commodity chemicals, the production method, tends to change every 50 or 100 years. It takes a long time. The global economy really has to change in order to make a new system more economical.

21:54For 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. Both of those industries' growth have slowed, and that is leading to a domino effect where the price of cement has been rising. 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 we believe that it's no longer the cheapest way.

22:32Is it more expensive to make it from calcium silicate? In the modern economy, we think that we'll be lower cost at scale. 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. So what about the strength of the end product? I mean, is it as good as Portland cement? So it is Portland cement. It is? Yeah, it is Portland cement. So that's the key thing, right? We don't think global adoption will happen if it's not Portland cement, or at least it won't happen quickly.

23:08All right. So you basically say calcium silicate, which is a type of rock that's abundant. It's available around the world. It has all basically the same essential properties as limestone that 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. That's right. So calcium silicate rocks, they don't have any CO2 in them. So 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?

23:46So 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 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.

24:24Just sitting on the ground, it will react with CO2 in the air to permanently sequester CO2. So 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? 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. So when you've got an empty quarry, oftentimes they get filled up with water, right? But you would just fill it up with this material.

24:57Yeah. And there's no risk of it leaching or anything. It's just basically a carbon store. That's right. This is a normal rock. 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 carbon from the atmosphere by sequestering it in this byproduct that comes out of the process, this magnesium. That's right. And magnesium carbonate is baby powder. So we basically make synthetic baby powder passively that removes CO2. 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.

25:41Hugo Leandria, I think is his name. Yes, that's right. And together you've basically founded the company called Brimstone. Yes. And the idea of the company is to what? Is to become a cement company like 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? 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.