This podcast is a recorded version of Avaana Climate Corner's fireside chat with Kelly Erhart on Technologies in Carbon Capture. The podcast will cover the coastal carbon capture work that Kelly is doing at her company Project Vesta, with an explanation of how the technology works and its scope. It will also explore the carbon capture landscape as a whole, the scalability of these technologies, and any bottlenecks or barriers that they face. The episode ends with a QnA that further expounds how carbon credits are calculated and the potential for widespread adoption of her solution. The transcript of the episode can be accessed here:- https://avaana.simplecast.com/episodes/technologies-in-carbon-capture
[00:00:00] Shruti Srivastava: Hi, everyone, and welcome to another fireside chat at Avaana Climate Corner. Today we have with us Kelly Erhart, the co founder and president of Vesta an ocean based carbon dioxide removal company. Kelly has a multidisciplinary background and is committed to reframing complex issues into scalable, holistic solutions.
[00:00:19] Shruti Srivastava: She has commercialized sustainable technologies, provided strategic direction to multistakeholder initiatives, managed disaster relief projects, produced large scale international events, and consulted for climate change mitigation projects. Vesta is a public benefit company which designs, executes, and measures carbon removal projects based on its nature based solution known as coastal carbon capture. This works by deploying olivine sand in coastal areas and wetlands, accelerating the Earth's natural long term process of rock weathering to reduce ocean acidity and remove carbon dioxide. Kelly will talk more about Vesta's technology and why it holds so much promise.
[00:00:57] Shruti Srivastava: Hi, Kelly. Welcome to Avaana Climate Corner.
[00:01:01] Kelly Erhart: Hi, thanks so much for having me.
[00:01:03] Shruti Srivastava: Kelly, you've had quite a fascinating journey with several years working on a multitude of solutions for climate and sustainability. Would love to hear more about what ignited this interest and how did Vesta happen?
[00:01:15] Kelly Erhart: Yeah. So originally I studied biology. I've always been an environmentalist and interested in how humans can positively interact with the natural world and ways that we can intervene that are beneficial to the natural world. And so that's looked, as you mentioned in the intro, that's looked like a number of different things throughout my career.
[00:01:32] Kelly Erhart: And originally I worked more in the sustainability space, more of the terms of sustainability that many of us work in in the ESG space and then on a solution for actually a waterless toilet. That was my first company. It was a waterless toilet company that decomposed waste very rapidly and provided liquid fertilizer as the output. And then I moved from working on more of the sustainability side of things to working on carbon dioxide removal technologies about six years ago, having realized that we as a society are falling really behind on our climate goals.
[00:02:05] Kelly Erhart: And as scientific consensus built towards understanding that we do not live in a world where reducing emissions is going to be enough anymore to meet our climate goals, we have to do really large scale carbon removal. I wanted to turn my attention to focus on that and so since then I've worked on a couple of different technologies.
[00:02:22] Kelly Erhart: I started my career working on a commercialization strategy for direct air capture and then moved into a more soil based approach in a regenerative agriculture application. And I started Vesta back in 2019 after doing a broad suite of research trying to understand where there were solutions that had really untapped potential for large scale carbon removal and that could provide carbon removal in a way that is cost effective and very scalable. And I came around to the core sort of technology behind what we do in academic literature. And so there'd been about 30 years of academic support behind the solution, behind coastal carbon capture, which is known in academia as coastal enhanced weathering. And all the papers were pointing to real life field trials being the clear next step to test the solution and validated as a really large scale climate solution. But no one had ever made it out of the lab even after three decades or more of support for the solution type.
[00:03:25] Kelly Erhart: And so my co founders and I really wanted to see if we could make that happen. So we started Vesta back in 2019. In 2020, we talked to a leading expert in the space and they said, yes, this is really interesting, but it's going to take a decade or more to get a field trial live. It's just too hard. There's too many stakeholders that need to be involved. It's scientifically very difficult. But after two years of operations last year, we launched not one, but two field pilots. So we're really excited to now be generating the first ever field data on this solution. And it's incredibly positive.
[00:04:01] Shruti Srivastava: Can you help us understand the overall carbon capture landscape from a technology lens? And how would you look at these various technologies from a scalability angle? Would they be, for example, deployment ready? What would it cost?
[00:04:15] Kelly Erhart: Yeah, so there's many ways to do carbon dioxide removal, right? When we're talking about carbon dioxide removal or CDR as the helpful acronym we're really just talking about capturing carbon dioxide from the atmosphere and locking it away for a period of, decades or years to even centuries and doing so in plants and soils or doing so in the ocean or geological features or even in products.
[00:04:38] Kelly Erhart: So there's many ways to do this. And today, many of them are being posed for really large scale impact. I think there are costs and benefits to each type, right? So with afforestation or reforestation, we're planting really big new forests that have the potential for scalable carbon removal today, but ultimately the carbon removal that we're doing in forests is going to be impermanent.
[00:05:04] Kelly Erhart: So that means that we're doing temporary removals the trees and the plants grow and absorb carbon dioxide, but when they die, they will re- release that carbon dioxide. So we're talking about storage on the order of decades. It's still great, but when we're thinking about the climate problem, it's one that is going to last. Carbon dioxide that's in the atmosphere today is going to last hundreds of years and in some cases, even thousands of years.
[00:05:27] Kelly Erhart: And so it's important that we think about permanent solutions, so we're not just kicking the can down the road. There's, of course, also soil carbon sequestration, where you can use different agricultural practices and increase the amount of carbon that's stored in soils. Also great and really helpful when integrating with local communities and practices that are already underway and providing some additional support to the idea of better yields and things like that. But again, there's a lack of permanence on the order again of decades. And then we have biochar creating kind of charcoal and burying it or plowing it into fields, which is another great nature based solution but can again hit scalability barriers in some ways and right now there's a lot of movement in the biochar space we're seeing new methodologies for measurement coming online, it's getting a lot of attention.
[00:06:22] Kelly Erhart: I think there are still some kind of questions around the ultimate scalability of biochar, just given the amount of biomass that would be needed, but it's a promising solution. There's bioenergy with carbon capture and storage, or BECCS as it's acronymed to be, where we capture and sequester carbon from biofuels and bioenergy plants, which again is really exciting. One of the main barriers to scale there is again biomass that would, be required to do this at scale. Let's get this to a gigaton or billion ton levels of removals, it would require a lot of land mass to grow the necessary biomass. And then we have this field of enhanced rock weathering or enhanced mineralization where we spread crushed rocks over land or into the ocean to absorb carbon dioxide or within the world of mineralization, you're using these minerals that can be exposed to carbon dioxide rich fluids or the air to mineralize more quickly. So there we're talking about everything from what we do to even mineralization, that can extend to what, the company called heirloom does, creating more limestone. And then there's direct air capture which gets a lot of attention these days, building these machines that could suck carbon dioxide directly out of the atmosphere and either make value added products with it or bury it or, inject it into the ground.
[00:07:42] Kelly Erhart: So direct air capture, again, really interesting. I think one of the main concerns there are cost. So direct air capture is currently very expensive to do on a ton by ton basis. We're talking about a $1000 to $2, 000 per ton of removal and there are many companies that have incredibly ambitious goals for how cheap it could get but there are some serious scaling limits there. We're still talking about the hundreds of dollars of cost per tonne with direct air capture.
[00:08:11] Kelly Erhart: The other component of direct air capture that's a limit is the energy intensity, roughly 1000 to 2000 kilowatt hours per ton of carbon removal. And ultimately, if we're going to power direct air capture to continue to be net negative, it needs to be powered by renewable energy technologies, which, of course, is a scarce resource. So that, and then some of the sort of industrial requirements as well to build direct air capture plants are of concern.
[00:08:35] Kelly Erhart: But I think it's a solution that many are excited about, especially because of the opportunity for value added products and the ability to work within the existing sort of oil and gas industry abandoned infrastructure and things like that. And then on the back of direct air capture, point source capture, putting, carbon capture facilities directly onto flu stacks. And then there's a whole world of ocean based methods from blue carbon in salt marshes and seagrasses and mangroves, which is akin to afforestation and reforestation, to ocean alkalinity enhancement, where you either spread alkaline minerals in the ocean, like what we do, or you inject alkalinity directly through a chemical process in different ways to work with the natural nutrient flows of the ocean to try and advance carbon removal. Some of those techniques are a little bit more contentious based on some projects that happened a few decades ago, but that's the overall suite of technologies.
[00:09:33] Kelly Erhart: Again, they all have their costs and benefits, and they're at different levels of maturity, which means that they have different things to pioneer, right? Within the direct air capture space there's a lot more technical advancement needed to get beyond small scale to large scale. So different physical problems, as you move from a 4, 000 ton plant to 100, 000 ton plant to a million ton plant. Because we're doing the first ever field sites, we're generating the first field data, which is really to say that we are pioneering methods for measuring this process in the ocean.
[00:10:04] Kelly Erhart: So one of the big concerns in the carbon removal space is how do you directly measure the carbon removal process and prove that your process is in fact removing carbon from the atmosphere, not having any adverse effects, and that on a net basis it's creating positive impact is really critical to being able to have a sustainable business model and and build the market on that basis. I'll stop there with the sort of broad overview.
[00:10:28] Shruti Srivastava: That's extremely helpful. And you said that Vesta uses coastal carbon capture. Can you tell us more about the technology and why that holds so much promise?
[00:10:41] Kelly Erhart: Yeah, so coastal carbon capture is ultimately accelerating the Earth's natural long term carbon cycle. So when I spoke about afforestation and reforestation, that's working with the short term carbon cycle, the process that happens quickly on Earth where carbon is absorbed into plants and then re released when they die.
[00:11:02] Kelly Erhart: But the long term carbon cycle is actually what regulates carbon levels on Earth and does so over millennia. And is really what's responsible for the 99. 9 percent of all carbon on Earth being stored in rocks. And this process occurs through a series of natural chemical reactions that happen between the atmosphere, alkaline minerals and rocks, and the ocean. And so what happens here is when rain falls on alkaline rocks and enter into groundwater as bicarbonate. So this chemical reaction occurs. And then as the water moves into the ocean, it transforms into calcium carbonate and can be used by marine organisms to build their skeletons and shells and eventually turns back into limestone.
[00:11:46] Kelly Erhart: So this is the slow carbon cycle. And at Vesta with coastal carbon capture, we're accelerating not that entire cycle, but the carbon removal part of that process. So we take olivine, which is an abundant natural mineral. It's found on every continent; actually makes up over 50 percent of the upper mantle. We grind it into a sand and then we add that sand into coastal areas. So coastlines and salt marshes, and when it dissolves in seawater, it removes carbon dioxide from the atmosphere by generating new alkalinity in the ocean. And so that is the process by which we can flux carbon out of the atmosphere and store it in the ocean in a way that is safe and permanent.
[00:12:25] Kelly Erhart: So currently the ocean absorbs a lot of carbon as carbonic acid. So our oceans have become very acidic since the Industrial Revolution. And so when we add alkalinity, we're essentially increasing the ocean's buffer capacity to continue sequestering and storing carbon dioxide. And there's a few really great advantages to this approach. It's highly permanent, on the order of 100, 000 years or more of storage in the ocean. We are able to do so in a very scalable way. So there's trillions of tons of olivine on earth. So there's plenty of the material and it would only take a very small amount of coastline to get to a billion ton removal scale.
[00:13:03] Kelly Erhart: So we're talking about a billion tons or more of removals a year, and the ultimate cost is very effective, so roughly $21 per ton at scale with extreme energy and life cycle efficiency here. And then of course there's co benefits associated with it related to reducing ocean acidity locally, and also helping to support coastal communities and ecosystems that are currently suffering from sea level rise and erosion. So by collaborating with them, we can add this sand to eroding coastal systems to help with coastal resilience efforts, which is exactly how we've brought the solution into the world today.
[00:13:43] Shruti Srivastava: There have been some segments that have raised concerns about further interference with environmental systems particularly when it comes to using oceans for sequestration. How would you look at potential environmental side effects from accelerated weathering and increased ocean alkalinity especially since field trials are yet to begin?
[00:14:02] Kelly Erhart: So I guess the one edit on that is that at this point we have done field trials of ocean alkalinity enhancement. They are the first ones and we're just publishing the first data from these sites but they have just begun as of last year so it's exciting.
[00:14:16] Kelly Erhart: So of course Whenever we're intervening in the natural system, we want to be sure that we're not causing harm where we thought we would be creating benefit. And so ecological safety is one of the core components of our research program. So since 2019, that's been one of our largest questions that we've been studying in the lab and now in the real world, in the field.
[00:14:38] Kelly Erhart: So when we're talking about ocean based removal there's very different environmental concerns depending on the solution. So Vesta is driving sort of a perturbation in the abiotic inorganic carbon space, which is carbon removal in the ocean related to kelp or macroalgae cultivation or a series of other approaches that involve biological systems. And that creates even more complexity. So food chains and nutrient cycling are very complex, so the downstream impact that's possible there is a bit complicated. And so there's a lot of question right now in, in the biological ocean based removal space. In the abiotic systems that we work within, the concerns are different. So with olivine, the main concern that exists for our solution is trace metal content. So olivine has trace amounts of nickel and chromium in it. But what we've been able to show is that it won't be harmful to marine life, introducing olivine into new coastal areas. Olivine dissolves over the course of decades, and as it dissolves, it generates this carbon removal reaction, but olivine dissolves again over the course of decades, and it's dissolving into a reservoir the size of the ocean, and so when you do the math there, you don't move the needle on nickel concentrations or really anything in the water column, which is actually why we need such sensitive instrumentation to measure our carbon removal because it's important that we are able to measure. And because of the low amounts of changes in this very large reservoir it's very difficult to measure changes. There's just not much that happens. And that coupled with the fact that coastal systems have a very short residence time, water moves very quickly in this huge system, and a very small amount of sand dissolves over decades it doesn't move the needle on things like nickel and chromium.
[00:16:31] Kelly Erhart: And so prior to doing our field deployments last year, we did a lot of lab based research. We did a variety of ecotoxicology tests on EPA model organisms following United States EPA protocols on everything from diatoms, these things at the base of the food chain, all the way up to fish and looking at things like growth, fertilization, mortality. And then we did our field deployment. And we're able to execute two field deployments in the United States, and we now have field data and an experiment where we've placed oysters, very sensitive organisms in trace metal concentrations. We're feeling incredibly positive about the effects here and based on, models of doing this at larger scale, again it's hard to be concerned about negative impacts related to trace metals with our approach.
[00:17:19] Kelly Erhart: We are still taking it very seriously and we plan our sites with incremental levels of scale to be able to measure at each level. But at this point, we're feeling quite confident about that. And then again, with every different solution has different concerns. Some of the other ocean alkalinity enhancement approaches are doing direct injection of alkalinity, which can cause an alkalinity spike and can also cause some other effects but a bit distinct from what we do.
[00:17:44] Shruti Srivastava: Got it. Great. We would love to understand more about what it would take for implementing these technologies at scale. What kind of cost structures one should expect? And in addition to costs what would you see as other bottlenecks when it would come to scaling these technologies for large scale impact?
[00:18:01] Kelly Erhart: Yeah so in terms of cost, the cost ranges pretty widely, depending on if it's a more technological or industrial approach or a nature based approach, right? Talking about afforestation, reforestation, these solutions can be in the tens of dollars per ton. And then getting up to direct air capture, we're talking about thousands of dollars per ton.
[00:18:23] Kelly Erhart: So it really depends on the kind of infrastructure that's needed. I think that many solutions that are more technologically based, they have these very ambitious targets for getting into the, $ 150 to $300 per ton range of carbon removal. And I think the one thing to note there is that those numbers are based on quite a bit of technological advancement and additional research and development costs.
[00:18:52] Kelly Erhart: So right now I think much of the industry is targeting towards an eventual carbon price of settling out somewhere around a hundred dollars per ton. And so many folks are trying to get to that point. Again, what's exciting about Vesta's Technology is that it can get to about $21 per ton, and that number is not based on massive technological leaps or improvements. That number is based on largely the efficiencies that are already embedded into the supply chain. So because we work with existing industries, mining, grinding, shipping, transportation, deployment industries, we as humans have been moving bulk commodities around the globe for more than 100 years so we know how to do that and we know how to do that pretty efficiently. So for us that's really one of the benefits that we lean into, is the cost effectiveness at scale. We think that there's really a case to be made that in the carbon markets where, carbon dioxide removal is procured the solution that provides the lowest cost approach to permanent removal will really do well in this market.
[00:19:53] Kelly Erhart: And so one of our main goals is to be able to provide that lowest cost permanent removal solution.
[00:20:01] Shruti Srivastava: Great. And what kind of go to market strategies and business models are you seeing emerge in the carbon capture space? Who is going to pay for it? Who are the different stakeholders that are going to be involved?
[00:20:16] Kelly Erhart: The majority of carbon removal companies base, at least some part of their business, if not all, on selling carbon credits. So there's the voluntary carbon market where corporations and individuals, but mainly corporations, are voluntarily choosing to purchase carbon removal to offset their emissions.
[00:20:34] Kelly Erhart: Whether it's for their own internal climate goals or what have you, this market is a wildly growing market. It's increased more than 60 percent year over year for the last couple of years. So we're seeing a lot of growth in the voluntary carbon market. Last year Frontier, which was a coalition between a number of large buyers, including Meta, McKinsey, Alphabet, Shopify, Stripe, and a few others, they came together and they committed nearly a billion dollars to pre purchase agreements for new, solutions in the carbon renewals already and a lot of new solutions are selling into the voluntary market. And then, of course, there's the compliance market where governments and international groups mandate that polluting companies offset their emissions by procuring carbon offsets.
[00:21:22] Kelly Erhart: And so that is really the main business model that we're going after and that many companies are going after. Some companies have additional revenue streams related to value added products they create. So there's the creation of concrete, for example, with some carbon removal companies. Some direct air capture companies are working on things like sustainable aviation fuel to creating synthetic fuels out of captured carbon.
[00:21:46] Kelly Erhart: Other, other carbon based products as well, so plastics and things like that. So there's a series of approaches that you can take but the core of them are usually selling into the carbon market. Which again, a lot of people are targeting to settle out around $100 per ton. Today that's not the price of carbon that's largely being traded. The EU ETS, which is one of the largest emissions trading schemes did hit 100 per ton this year of carbon traded. But broadly across the globe there's a much lower price being traded because of the lack of differentiation between emissions reductions, credits and carbon avoidance credits.
[00:22:26] Kelly Erhart: So that's something that's still being shaken out in the industry.
[00:22:31] Shruti Srivastava: And given that this is a nature based solution, how are you looking at measuring the quantum of carbon removed and, consequently using that to sell the credits and price the credits?
[00:22:44] Kelly Erhart: Ultimately what we do is we measure changes in seawater chemistry in the field. And so again, this inorganic carbon pathway is very well understood by scientists in the field. What we do is we take in ocean measurements. So we measure things like changes in alkalinity, dissolved inorganic carbon, pH and we measure that directly in the water column.
[00:23:06] Kelly Erhart: And we've demonstrated now in our field trials that we can measure the alkalinity generation resulting from our treatment. So there's multiple ways that we can document carbon removal in the field. We take those measurements. And then we've built models, some proprietary models and then some models that are publicly accessible. We plug these measurements into these models that allow us to model things like solution rate, they allows us to model how the sediment moves in the ocean and takes in other components as well that help us to understand the full effects of the carbon removal. So tides, wave action, ocean currents, pH, water temperature. And we ultimately use our software based method here that is not too dissimilar from other nature based forms of removal. So it's in-field measurements that are plugged into models that give you a larger understanding of this sort of spatial and temporal scale of carbon removal.
[00:24:01] Shruti Srivastava: Got it. And we alluded earlier to stakeholder management as well, right? And we at Avaana often quote our own spin on a local saying around how it will take a village, in this case to solve for climate. Deploying such solutions is going to require engagements, partnerships between various kinds of stakeholders, governments, civil society, techies, capital allocators, enterprises.
[00:24:25] Shruti Srivastava: How does Vesta look at approaching multi stakeholder management here?
[00:24:31] Kelly Erhart: Yeah. So as you said it's going to take, it's going to take a lot of stakeholders to bring this to bear. So if any technology is going to get to a billion tons of removal a year and get us towards our climate goals where we're removing anywhere from 5 to 10 billion tons of carbon dioxide every year it's going to take a lot of different industry participants, government stakeholders, local communities. And no one can be left out of this conversation if we are talking about really getting to scale. So the stakeholder engagement landscape looks very different in different countries. Starting in the U. S. We engage at every level, from the local, to the state, to the national level. And so we, get permits at all of those levels. We do a lot of local stakeholder engagement with the communities that live where we're working. And then in other countries, that looks slightly different depending on the sort of permitting structure and the ways that these technologies are regulated.
[00:25:24] Kelly Erhart: So for us, on the policy side of things, it's going to take large scale international coordination to appropriately regulate these different technologies and ensure that they're able to move towards adoption in a timely, but careful and rigorous manner, right? And so I think we need a lot more intergovernmental support and funding for carbon dioxide removable technologies and that support is again going to mean international frameworks for doing this that are supportive and clear, because CDR technologies are really in a very nascent and pioneering space right now.
[00:26:00] Kelly Erhart: So there's that and then I think the last thing to mention is community engagement, which is something that we think about a lot at Vesta. We really believe that in order for climate solutions to really scale, both climate and community has to win. And while we've started doing coastal carbon capture in the United States, coastal carbon capture is most effective in places where waters are warmer and wave energy is high. And we also really want to site our projects that are more proximate to the mine sources. And all of these things lead us to know that coastal carbon capture will likely work best in the Global South. And so we didn't want community engagement to be an afterthought for us. So we spent about a year and a half following a participatory governance approach where we learned about rural small island communities in the Dominican Republic, and we worked with them there to understand their perceptions around carbon dioxide removal and published a report on localized governance and perceptions of CDR in the developing world.
[00:27:01] Kelly Erhart: And also did a workshop with them where we worked to understand their needs and desires and then directed some of the proceeds of our work for use by the communities themselves to fund workshops so that they could build new small textile businesses. This is one example of what we're embedding into our DNA from an early moment to ensure that coastal communities' voices are heard, included and can benefit from some of the work being done in carbon dioxide removal.
[00:27:28] Kelly Erhart: And as with all of these answers, it goes without saying that each solution has different things that they need to do, different ways they need to engage communities. But we really do think it's important that communities are engaged from the very local level up to the national and international level in order to actually enable scale.
[00:27:44] Shruti Srivastava: Great. What would be your advice to founders that are early in their journey in building solutions for carbon capture?
[00:27:50] Kelly Erhart: Yeah, my advice would be funding is very hard, in terms of getting the kind of funding that's necessary to scale a carbon removal solution. And so I would advise looking at different ways to fund your research. Like definitely invest in federal grants and getting government funding where possible. Spend time searching for those and applying to them. Anywhere that non dilutive funding can come in is going to be really supportive to the company, because there's so much research and development costs associated with these technologies. And while venture capital is really helpful for scaling the business, it's very expensive for doing research. And so Vesta actually has a hybrid org structure where we started originally as a nonprofit and then we spun our company out of that, and today we actually maintain a relationship with a 501 C3 fund.
[00:28:42] Kelly Erhart: So our ecological safety research, our community engagement research, the kind of work that needs to be published into the open source, that work can be funded by philanthropic donations and then our technology that we're developing and are the real core of the commercialization strategy is what's being developed in our company.
[00:29:00] Kelly Erhart: And so that hybrid structure has worked really well and has been supportive to us in ensuring that we can do the foundational research in a way that is transparent and accessible while also building a business that's going to create a sustainable model for us to really bring this to scale.
[00:29:16] Kelly Erhart: So I would say, get creative about your financing and spend a lot of time thinking about how to bring the right kind of capital in for the stage of development that your technology is at.
[00:29:27] Shruti Srivastava: Great. What would incentivize economically a Meta or a Stripe to prioritize your solution, your emission reduction credits versus a clean of carbon avoidance credit at $10 per ton.
[00:29:41] Kelly Erhart: Yeah, so I think there's a couple things. So many of these carbon avoidance credits at $10 a ton are really not creating much climate impact anymore, right? There's additionality questions: some of these projects would be done without the sale of credits associated with them. And because of the scrutiny that's coming into the climate space right now, especially around carbon offsets, many companies are moving away from purchasing these really cheap credits. Because when you look under the hood, again, there's not much climate impact that's happening there. And so companies are moving towards prioritizing real removals that are permanent and have other benefits associated with them.
[00:30:20] Kelly Erhart: And when trying to prioritize removals, you very quickly see that there is a real scarcity of supply in the market. And so companies that participated in frontier, for example, and the many other corporations that are purchasing permanent removals that are more expensive today are doing so because they want to support the development of an industry because they know that in order to meet the our global climate goals and their internal climate goals, we need a larger supply of permanent removal. And so by purchasing higher up the scale curve, which means that in the next couple of years or decades, they will have millions of tons of carbon removal to buy or even billions of tons of carbon removal to buy. So these companies are really interested in supporting and spurring an industry and in part, these technology or financial services companies are doing so because they have the margins to do it. So we're not seeing companies that have lower margins necessarily coming in and purchasing at these high volumes, but more and more we are seeing companies that have hard to decarbonize supply chains coming in and making sure this industry can exist and that there will be supply to purchase. And it's again in light of some of the scrutiny and the crackdowns that are coming in on the carbon markets and what's considered a viable product to buy to offset.
[00:31:43] Kelly Erhart: So the ratio for olivine to carbon removal is that it's just under a one to one ratio. So every cubic yard of olivine sand removes about a ton of carbon dioxide from the atmosphere. And the rate of that removal depends on the unique project site.
[00:31:59] Kelly Erhart: So there are some components, some sort of like things that we look to to speed up the carbon removal reaction. Again, that's very related to temperature, salinity, wave action things that we can pull the levers on as well as grain size and project design. So the grain size of the olivine, but roughly we're talking about a decadal timescale.
[00:32:18] Kelly Erhart: So we're talking about the olivine fully dissolving and fully removing the carbon dioxide from the atmosphere over the course of decades. So you can think about it as the time it would take you to grow a tree or likely less time than it would take you to grow a tree, but the end benefit is that the carbon is permanently removed from the atmosphere.
[00:32:36] Kelly Erhart: The last thing to say about the timescale is that olivine doesn't dissolve linearly. It dissolves in half lives. So we actually get the majority of the carbon removal reaction happening in the first 50 percent of the project's lifetime. 75 percent of the removal is going to happen in the first roughly 50 percent of the project's lifetime, which means that it's very helpful for carbon removal sales and the business model itself. And it also means that we have an interesting product at the sort of tail end of the project's lifetime that can be used. So yeah, so there's lots of levers that we pull to make the reaction more efficient and it's one of our main areas of interest. The last thing that I'll say is that today I've talked about coastal carbon capture and the applications of coastal carbon capture on coastlines and marshlands but we've also developed another application that's based on the same chemical process, and it's actually a bioreactor which can use mine waste and mine tailings and digest these tailings for accelerated carbon removal and also for valuable metals extraction. So the way that works is ultimately when you go and you mine for valuable metals like chromium and nickel and cobalt, you have to mine, you have to drill through a lot of olivine to get there.
[00:33:48] Kelly Erhart: This is actually very true in India where a lot of olivine is located. And so olivine and other alkaline minerals are often the waste product that are just sitting at mine sites. And so we've developed a technology that you can think of as similar to a wastewater treatment plant, but instead of treating wastewater, you're treating waste mine tailings.
[00:34:08] Kelly Erhart: And when the microbes that we've developed are in the presence of this, or in this bioreactor, they help to dissolve the minerals. And what you get there is this accelerated carbon removal reaction, which can happen even faster than what I've just been describing in the oceans. It also can extract those metals that are present in the minerals.
[00:34:28] Kelly Erhart: So it's an interesting approach that's much earlier on the technological development side of things, but it still sits inside of the same school of chemical reactions. It's a new approach.
[00:34:40] Shruti Srivastava: Could you dive deeper into the quantification of the credits and how do you go about the MRV?
[00:34:45] Kelly Erhart: Sure. The way that we do MRV as we have hardware that we've developed, so we use a series of different techniques to measure these changes in seawater chemistry in the field. So one of the techniques is measuring water that exists in the poor water.
[00:35:02] Kelly Erhart: So we're measuring poor water, which is the water that exists between the grains of sand in the ocean. And the reason we have taken measurements there is because the water moves more slowly in between the grains of sand, and so you get more of a buildup of chemical reaction products there, so it's a good place to look if you're looking for concentrated reaction products.
[00:35:20] Kelly Erhart: Another way that we measure is through these these things called benthic flux chambers. And so benthic flux chambers are isolating a part of the water column which again, putting a shell on a part of the water column, that's allowing us to again, see a more intense buildup of chemical reaction products. So we get a good signal there. And then we're also exploring a number of different ways to take measurements directly in the water column.
[00:35:45] Kelly Erhart: So right now our team is actually out at one of our upcoming field sites in North Carolina, doing some methods testing on new pieces of hardware that we've been developing to take direct measurements in the field. We take those measurements and then we plug them into our models. So our models are modeling dissolution rates over time.
[00:36:04] Kelly Erhart: They're modeling the immense variables that exist in the ocean system. So these are proprietary models that take in all variables from ecological variables to geomorphological variables to variables in the water. And we create a new model for every project site based on the parameters of that site.
[00:36:23] Kelly Erhart: We run those models with the field data and then that output is then plugged into larger regional models that again give us a sense of spatial and temporal difference and real carbon removal rates. And then those models can even be plugged into Earth systems models. So again, this is similar to the way that we do any nature based removals measurement.
[00:36:45] Kelly Erhart: Because you can't just put a dome on a natural system and watch the carbon go in and out. You need to measure what you can measure and then use models to best approximate the removals happening over time. It's what we do in forestry as well, taking, direct measurements are using satellite imagery or LIDAR and the plugging that into models. So that's how we do it.
[00:37:04] Shruti Srivastava: Great. I think that brings us to the end of today's conversation. Thanks, Kelly, for taking time and for sharing a fascinating story and what Vesta is building with all of us here.
[00:37:19] Kelly Erhart: Yeah, thank you so much for having me.