Episode 62 Transcript: Draining the tub: Using the ocean to capture carbon

Molly Wood Voice-Over:

Welcome to Everybody in the Pool, the podcast where we dive deep into the innovative solutions and the brilliant minds who are tackling the climate crisis head-on. I'm Molly Wood.

This week, as the planet heats up and the clock ticks down, finding ways to pull carbon dioxide out of the atmosphere has become more than a talking point—it’s a necessity.

We’re seeing innovations everywhere, from direct air capture technologies that vacuum CO2 from the air to natural solutions like reforestation and enhanced soil management. But this is controversial as I’ve mentioned in previous episodes, some think it’s a high-tech band-aid that lets bad practices go on unchecked. Others believe the economics will never work, but the fact is even our least ambitious climate goals assume that we’re somehow capturing or sequestering billions of tons of carbon dioxide on top of emissions cuts, so we darn well better talk about it. Let’s go …

Steve Oldham:

Hi, my name is Steve Oldham. I'm the CEO of a company called Captura. We're a carbon removal company. We take CO2 out of the atmosphere via the ocean.

Molly Wood:

Talk first, I think, at a high level about carbon capture and carbon removal. And this is an increasingly important topic in the climate conversation, I think, as a lot of people realize we can't hit the goals we have set for ourselves even by 2050 without removal. Is that fair to say?

Steve Oldham:

Yeah, I think there's a really good analogy for this, which is thinking of the atmosphere as a bathtub filling with water, the atmosphere filling with CO2. So imagine that bathtub being filled with literally billions of taps, each of which is flowing water into the bathtub. So of course over time, the bathtub gets more and more full and that creates a climate problem. What carbon capture is, is trying to turn off those taps. So many of those taps are turned off, for example, if you buy an electric car and you give up your existing gasoline car, that would turn off one of those taps. Many of those other taps are plants that emit CO2 into the atmosphere as part of that process. So carbon capture says, let's capture that CO2 as it's emitted and put it back underground, which of course turns off that tap.

Carbon removal looks at the problem the other way, which is to say if you are filling the bathtub with water, you can also pull out the plug as a way to reduce the amount of water in the bathtub, CO2 in the atmosphere. So what our company does and others like us is we take CO2 directly out of the atmosphere. That means that if we can't figure out how to turn one of those taps off or millions of those taps off, you now have a method of making sure that the atmosphere doesn't become too full of CO2. And of course, we can also remove yesterday's emissions. Now things like electric cars, solar panels, fantastic moving forward, but they don't remove the emissions of yesterday, and carbon removal does.

Molly Wood:

It's like a small drain at the bottom of the bathtub, if you will. OK, wonderful. Thank you for that distinction, too, because people are hearing about carbon capture, and they're hearing about carbon removal, and they're not necessarily understanding that they're different things. OK, so then tell me, before we again get to your specific solution, what are the forms of carbon removal? Like, how are various companies doing it? And then what made you settle on the approach that you're taking?

Steve Oldham:

Absolutely.

Steve Oldham:

Yeah, it's a great question. The good news is that there are lots of candidate ways in which we can remove CO2 from the atmosphere. And of course, there is so much CO2 to remove that we need lots of different ways. There is an XPRIZE for carbon removal, and they split the sector into four. Mechanisms that remove directly from the air, mechanisms that use the ocean, mechanisms that use the land, and mechanisms that use rock. So all of those are interesting and good solutions. You can mineralize CO2 into rock. You can use soil as an absorbent for CO2. You can use machines to extract directly from the atmosphere. What we do at Captura is we utilize the natural ability of oceans to capture CO2 and that's our distinction.

Molly Wood:

So tell us about the natural ability of oceans to capture CO2. How do they, I know this is a huge deal, right? But most people don't know it exactly.

Steve Oldham:

Yeah, so most people don't know this. Yeah, most people don't know, but the ocean is a tremendously effective carbon removal device. Today, for every ton of CO2 that we emit through your car or your flights or whatever it is, the ocean absorbs about 30%. So that's great news from a climate perspective. Without that, we would be in really significant climate problems. However,

It's not such great news for the ocean. You may have heard of ocean acidification, the blanching of the coral reefs, increases in ocean temperatures, which create localized bad weather patterns. These types of things are the impact of there now being too much CO2 in the ocean. So what Captura aims to do is to say, look, if the ocean is such a great carbon removal device, it's already there. It's massive. It's a huge scale, 70 % of the surface of the ocean, of the planet, I'm sorry, is ocean. Can we use that in a way that doesn't harm the ocean to increase the amount of CO2 we take out of the atmosphere? And the good news is the answer is yes, and that's what Captura's process does.

Molly Wood:

How does the ocean remove those emissions? Is it absorption? It's because of the plant matter in the ocean? Get a little more specific there if you wouldn't mind.

Steve Oldham:

It's ocean chemistry and it's described by something called Henry's law. So essentially the ocean and the atmosphere work in equilibrium with respect to CO2 content. It's all to do with partial pressures of gas in a liquid versus the air. The best analogy of this is that I like to use is considering a can of soda. So the people who make a can of soda put excess CO2 into the soda to make it fizzy.

Molly Wood:

Mm -hmm.

Steve Oldham:

When you open that can and you pour it out into a glass and you leave that glass on the table, then you come back half an hour later, the soda's gone flat. So why is that? Well, it's because there's too much CO2 within the soda compared to the atmosphere. Henry's law says there has to be an equilibrium between the two. So that's why you see the bubbles of CO2 coming out of a drink when you leave it on the table. And of course you then get to equilibrium and at equilibrium, the drink has now gone flat. It's now got the same amount of CO2 content as the atmosphere and Henry's law says that's stability. So we see that process every day, we don't really think of it. What Captura does is we do it the opposite way. Think of taking the CO2 out of the soda, obviously not the soda, the ocean. But by taking CO2 out of the ocean, you create the same disequilibrium. So the ocean absorbs CO2 from the air. And in this way you've affected carbon removal from the atmosphere via the ocean, but you haven't changed CO2 levels in the ocean itself, so you avoid increasing acidification.

Molly Wood:

Right. OK, so tell me more about how you do this. It feels like a tricky dance.

Steve Oldham:

Yeah, I think it's a very elegant process. One thing to emphasize is CO2 in the ocean is 150 times more prevalent than CO2 in the atmosphere. So if we try and take CO2 out of the atmosphere, we have to move enormous amounts of air to capture a small amount of CO2. It's 420 parts per million today. In the ocean, it's 150 times more.

Molly Wood:

Yeah.

Steve Oldham:

So we have to move 150 times less ocean water to be able to absorb CO2 from the ocean. So how do we do this? It's through a process called electrodialysis. Captura is an offshoot of Caltech. Our founders are Caltech professors. And they came up with a form of electrodialysis, and I'll explain electrodialysis in a second, that is significantly better than the state of the art today.

So what our process does, we pull ocean water into our plant. We take a small amount, about half a percent, and we soften it to convert it into brine. Brine is salt water. We then put that half a percent of brine through our electrodialysis.

Electrodialysis dissociates molecules. It literally splits them up and reforms them. So brine, salt water, sodium chloride, hydrogen, oxygen.

We take those four molecules and we convert them into hydrochloric acid and sodium hydroxide. Sodium hydroxide's an alkali. We take the acid that we made and we put it into the flow of ocean water going through our plant. That takes the ocean water up to pH four. And at that point, the acid and the dissolved inorganic carbon within the ocean react together and you're then able to extract CO2.

Molly Wood:

Mm -hmm.

Steve Oldham:

There's a stream using a gas liquid contactor. Think of that as literally sucking the gas out of the ocean water. Then last step, before we put that ocean water back, we add the alkali that we created, the sodium hydroxide, and that re -neuterizes the ocean water. Then we return it to the ocean. So that was a lot. So let me take a step back, it's a closed -loop process. The only inputs are renewable energy and ocean water. We don't require any chemicals to be added. We don't require any absorbance or anything similar. Then the only outputs are a stream of CO2, which you can measure, you can sequester, you can make low carbon products like sustainable aviation fuel and decarbonized ocean water. And that decarbonized ocean water has the same chemical composition. The only thing we did was we took its CO2 content out.

Molly Wood:

Right.

Steve Oldham:

and the atmosphere puts it back.

Molly Wood:

So it's really, I mean, what you're describing sounds like really almost a water purification technique. Like you're cleaning it out a little bit, reducing the CO2 content, putting that water back. And then what is the effect of that once the water goes back?

Steve Oldham:

Yeah, so when that water goes back into the ocean, you create that disequilibrium. Now you have less CO2 in the ocean than in the atmosphere, so the atmosphere puts it back. That process is instantaneous for the bit of the ocean water that touches the air. But of course, as you outflow water, think about when you're in a boat or something similar, that the flow of water coming out of the back of your boat churns some of it, goes deeper into the ocean, some of it stays on the surface.

So for the ocean water at the surface, you get immediate drawdown and replacement of the CO2. And then as the ocean moves and is choppy, the remaining water that comes out of the back of our plant is circulated to the top and it absorbs CO2. So at the end state here, you end up in a situation where the ocean's been unchanged. The CO2 we took out is replaced by CO2 from the atmosphere. And that's a good thing for the climate.

Molly Wood:

And that is why it feels to me that the obvious question you would get a lot is about unintended consequences since the ocean is a dynamic ecosystem that we know very little about. But it sounds like what you're saying is you're not changing that much.

Steve Oldham:

Yeah, this is utterly integral to us that we do not harm the ocean. So firstly, we add nothing. We're not adding anything into the ocean. No material, no chemicals, no additional rocks or biological matter that doesn't naturally occur in the ocean at the levels that maybe a process requires. We don't add anything. Number two, the only thing we change, we take out CO2.

Molly Wood:

Mm -hmm. Yeah.

Steve Oldham:

then the atmosphere puts it back, but it does so over a longer time period than it does takes us to remove it. That's a good thing because that reduces ocean alkalinity. So oceans really, really big. If you put one of our plants in the middle of the Pacific Ocean, it wouldn't make any material change to ocean alkalinity whatsoever. But in a localized bay where the ocean water stays pretty resident, now you can deacidify that bay.

Molly Wood:

Okay. Right.

Steve Oldham:

And this is a secondary benefit of our process because you're assisting in things like shellfish farming, muscle growing, where ocean acidification hurts those industries really badly. I want to emphasize one other thing as well. We're actually growing mussels in the outflow of our pilot plant today. So mussels are the most sensitive marine form of life to changes in ocean chemistry.

Molly Wood:

Okay, great.

Steve Oldham:

So by physically growing mussels within 100 % of our outflow, 50%, 25 % and so on, we're simulating that our outflow has no material impact on ocean health. So we treat it very, very seriously. Oxygen levels are maintained, soluble solids, all the important metrics that are in wastewater standards, we maintain all of those. And we're demonstrating that with our ocean health program, including the mussel growing.

Molly Wood:

Right. Well, and I feel like you made another important point there, which is that you're not trying to turn over all of the water in the sea. That the scalability of this is meant to improve smaller, more kind of localized bodies of water.

Steve Oldham:

Yeah, from an ocean health perspective, you can do that. From a climate perspective, again, the advantage, I think, of Captura's solution is the problem is really large. The carbon removal problem is immense. 10 billion tons a year of CO2, according to the IPCC, need to be removed from the atmosphere. Our process can use the ocean, which in itself is absolutely huge. And even if this will never happen, nor should it happen, even if you decided to remove all 10 billion tons using only capture as process, our impact would be, pardon the pun, a drop in the ocean to the ocean itself because it's so large.

Molly Wood:

What is the part of your process that's better than what had existed before? So it sounds like there have been efforts to do this. What's the secret sauce?

Steve Oldham:

Yeah, so I think it's not quite right to say there have been efforts to do this process. We call this process direct ocean capture. There have been studies in the past looking at the economic feasibility and the energy use. And the answer that came back from those studies was it can't be done cost effectively and at large scale unless you do two things. Number one, you find a much better form of electrodialysis.

Molly Wood:

Mm -hmm. Got it.

Steve Oldham:

than what existed in the market previously. And number two, you need a really efficient low pressure way of removing that CO2 from the ocean water once we've created that chemical reaction. So Capture has done both of those two things. Electrodialysis is about seven to 10 times higher performing than the best electrodialysis in the market. That came from our partnership with Caltech. And then the process of removing the CO2 out of the ocean once we've created chemical reaction, we've developed a technology which does that using just the pressure of ocean movement itself. So we don't need to pump water through our system, which of course becomes costly. So just the movement of the ocean, the motion of the ocean, is enough to allow us to run our process.

Molly Wood Voice-Over:

Time for a quick break. When we come back, some more specifics on how this whole thing works, future customers, and the key question … scale.

Molly Wood Voice-Over:

Welcome back to Everybody in the Pool. We’re talking with Steve Oldham, the CEO of Captura about how to scale the company’s ocean-based carbon capture tech and who’s buying it.

Molly Wood:

I'm starting to realize that the name captura works on so many levels. So what is the physical infrastructure then for capturing that flow? I mean, is it like a pipe in a bay? Yeah.

Steve Oldham: 

Right.

Steve Oldham:

Yeah, pretty much. You know, as I mentioned earlier on, there are lots of different ways to do carbon removal. Each has advantages, disadvantages. I think we have a lot of advantages. The disadvantage, of course, is we have to be by the ocean or on the ocean. So for us, once we've captured that CO2, we're looking to sequester it. We capture it as a gas. It can be compressed into a liquid. And then there's a variety of different sequestration solutions that involve, for example, injecting the CO2 deep underground into the same cavities and wells where oil and gas came from in the first place.

Conceptually, I like that. I like the idea of putting the CO2 back where it came from, back into geological formations where it can survive for 10 ,000 plus years. But you can also use that CO2. You can combine it with hydrogen and make, for example, a sustainable aviation fuel, which will go into an airplane existing aeroplane with no changes to the aeroplane itself. Of course when that fuel is burnt and the plane takes off, CO2 goes into the atmosphere, but it's the CO2 we took out in advance to make the fuel. So it's effectively a net zero fuel. Yeah.

Molly Wood:

It's like a real time offset. Yeah. Interesting. OK, so yes, thank you for leading us directly to that topic. Are you then making any of those products? Are you also in the business of reuse of this removed carbon?

Steve Oldham:

So for me, the single most important characteristic of any carbon removal solution or company is the ability to do things at a massive scale. So hopefully I've talked through the fact we don't need any input materials. The ocean already exists. These are good technological reasons why we can achieve large scale. Our business model also needs to be compatible with that. So we don't propose or plan to build every single plant ourselves, we would become a bottleneck. Instead, what we do is we license our technology to partners around the world. They build the plants. They have whatever sequestration solution is relevant in their local environment. They make sustainable aviation fuel if that's what they want to do. So our business ends at the production of CO2. There are businesses already doing sequestration and making fuel. We will leave those businesses to do what they do, but we want to be the best large scale and hopefully low cost approach to providing OSC02.

Molly Wood:

Got it. You have invented the one thing, the improved electrodialysis and process. And then how much does it cost to build a plant? How prohibitive could that be in terms of making this infrastructure widely available?

Steve Oldham:

Correct.

Steve Oldham:

Yeah, I think the way that I think of it overall, which is actually the way that most of the industry thinks, is what is the cost of a ton of CO2 removed? And how does that compare with the cost of trying to stop the emission of that CO2? And let's use aviation as an example, because we're all familiar with jumping on a plane. So the aviation industry has a really hard challenge to achieve net zero. They require a very high energy form of fuel be able to take off the heavier the plane is obviously the less efficient it is. So taking a plane and eliminating its use of fuel with hydrogen or electric plane we are many many years away from having those solutions.

So instead of trying to stop an emission in aviation maybe the best answer is that you remove the emission once it's occurred and there the economics becomes is your cost to remove lower than the cost to stop the emission. And in many cases, the answer to that is, is yes, about a third of the world's emissions are probably more expensive to stop than they are to remove. That's not saying we shouldn't be doing everything we can to stop emissions. But some are just just too hard, or too integral to our way of life, or maybe geographically not available. What if country X refuses to decarbonize the atmosphere? a shared resource carbon removal allows you to remove somebody else's emission as well. So the economics really is a question of the trade between what's the cost to stop versus what's the cost to remove.

There's a lot of discussion about what is an affordable carbon removal cost at the widespread economic level. The metric that I like to quote is in the US, the Department of Energy has set a 10 year target of $100 a tonne. And I think that's a good target. It's one that we're focused on achieving. And obviously the early plants cost more. But we feel the inherent cost advantages of our process, the use of the ocean. No absorbed, no absorbance, no byproducts to dispose of. These things give us a really good shot at achieving that cost number.

Molly Wood:

You do, okay.

Molly Wood:

It sounds like it's pretty important that whoever licenses this technology and builds a plant powers it with renewable energy, right? It is energy intensive.

Steve Oldham:

So, energy is an interesting question. I think any process that uses technology to remove CO2 is going to obviously require energy. For us, we've focused really strongly on being fully compatible with the renewable energy industry. The renewable energy industry has a characteristic where, unlike fossil fuel, where you can take it out of the ground when you need it and store it and transport it relatively easily, renewable energy occurs when the sun shines or the wind blows or the tides are coming in. And the market is either there at that time or it isn't. When the market is there, of course, the renewable energy is happy to provide the renewable, excuse me.When the market is there, the renewable energy companies are happy to provide the energy. But when the market isn't there, they either have to turn off or store. Both of those two things are expensive and inconvenient.

So we've designed our process to be completely compatible with renewable energy. We can turn off and turn on our entire plant very quickly. Our base load is quite low. Base load is the minimum that you need, is quite low. We can store excess energy in the form of acid and base. Remember I described how we made acid and base. That's a very energy intensive part of our process. So if renewable energy is available, during off -peak periods, we can use that energy, create excess acid and base, and then run the rest of the plant on a much smaller base load using the stored acid and base. The impact of this is we're actually really compatible with the renewable energy industry. And we actually help them by providing them with a customer who can take the energy as and when it's available, eliminating conflict with other forms of the nuclear energy uses.

Molly Wood:

Interesting. So that leads nicely into my next question, which is who are the potential customers for this? Like who could you, you know, give me some examples of who might build this plant either for the purpose of making sustainable aviation fuel or some other product or to attach to a desalination plant and maybe get carbon credits. Like how does it all come together for potential buyers?

Steve Oldham:

Yeah, it's a really interesting question. I think you can broadly split candidate plant developers into two categories. The first is new companies, companies that, like a Tesla 15 years ago, see a need and want to build a business around something. The technology is provided by Captura. They need to raise the funding, find the locations, do all those good things. And we see lots of new companies.

moving into those types of sectors.

The second one is existing energy companies of today, the renewable energy companies, the oil and gas companies. They're looking for, if you're an oil and gas company, you're looking for a new business line in the energy transition. We are going to have to transition from fossil fuels. And if you're an oil and gas company, you have shareholders, you have employees, you need to find another business line. So we think we're quite attractive from that perspective. And the renewable energy companies, we think we can provide them with a way to monetize energy that otherwise they're throwing away or spending a lot of money to store. And that's that off peak energy I talked about earlier on.

Molly Wood:

Right.

Molly Wood:

Can you say more about how this might replace a business line for oil and gas companies?

Steve Oldham:

Yeah, I mean, I think if you look at oil and gas companies, they have tremendous experience in multiple relevant areas, building complex plants, they do that all the time, operating them, sequestration of CO2 into the ground. They're in the business of taking things out of the ground. They have a lot of size, I can't say size, well, logical, it's always a hard word. They have a lot of experience in.

Molly Wood:

I feel like I'm really surprised to hear you say that because you don't seem like a person for whom any words are hard.

Steve Oldham:

No, that one's hard. So yeah, they have lots of experience in the underground geology and understanding where you can safely store CO2. So I see a lot of synergy and they have, frankly, they have balance sheets that allow banks and others to invest into them. So I see it as an industry with a lot of synergy, but it has to have obviously the will and the desire to build new business in carbon management. And some are like Captura, we're partnered with Equinor. We're building our first, sorry, our next pilot plant in Norway alongside Equinor. It's a good relationship. They add a lot of value to us.

Molly Wood:

And then again, to just put a finer point on it, how does that turn into revenue for them?

Steve Oldham:

So essentially you do one of two things. You either sell a carbon credit and we're seeing the emergence of a carbon credit market. If I go back to my airline example, if an airline has to achieve net zero because they're regulated to do so or their customers or their shareholders demand it, then they need to find a solution. They can either develop an electric plane, which costs a lot of money, or essentially buy a service to remove CO2 from the atmosphere. And that service at a certain dollar amount becomes a revenue line for a plant that uses Keptra as technology. Equally, if you take our CO2, add it with hydrogen, and make a synthetic fuel, you sell that synthetic fuel into the market. And that's how you create a revenue line.

Molly Wood:

Got it. Yeah. And so then you're an oil and gas company who says we have a net zero fuel. Yep.

Steve Oldham:

Yes, and there are various government bodies around the world that are defining what a net zero fuel needs to look like, and that's all good work. If you think about it at a very top level, the IPCC has estimated 10 billion tons of carbon removal is going to be needed. If you take a price of $100 a ton and add it to the 10 billion tons, it's a big number.

Molly Wood:

Right.

Molly Wood:

Yep. It seems like a good business to get into. And we should clarify, they've estimated 10 billion tons of removal via mitigation and or removal or pure removal on top of all of our efforts to reduce. Yeah.

Steve Oldham:

Right.

Steve Oldham:

Pure removal. Pure removal. That assumes that the various commitments made by governments around the world to achieve lower emissions are successful. Even with that, about 10 billion tons a year is going to be required. And the problem, of course, is that every day in which we don't achieve the decarbonization targets, the more CO2 ultimately would need to be removed to create a sustainable climate. So it's really a race against time.

Molly Wood:

Yeah, I think that it has not sunk in for people that it's additive, that removal is an additive imperative. Yeah, exactly.

Steve Oldham:

No, it's that bathtub analogy again. Imagine the bathtub overflowing in your house. That's not a good situation. It's the same with the environment we see here too.

Molly Wood:

Yeah.

Molly Wood:

We're going to need a bigger drain. So what is the sort of state of Captura now? Like where are you now? It sounds like you have some pilot plants either built or in development or both. What's next?

Steve Oldham:

Yes.

Steve Oldham:

Yeah, we have a fully operating plant at the Port of Los Angeles. We have a partnership with an entity there called AlterSea. They're a not -for -profit that are focused on promoting businesses that can utilize the ocean in a safe and sustainable way. So we have a hundred ton system captured per year. That's the capacity operating there. And then our next pilot will be in Norway with Equinor, be a 10 times scale up. And our view is after that we will have demonstrated all the technology, demonstrated the ocean health cleanliness of our approach and we'll then be ready to start building commercial plants.

Molly Wood:

Amazing. And then briefly, how did you come to this? What's your background that got you into this?

Steve Oldham:

I'm totally unqualified for this job. So my, my, my background is I was actually in the space and robotics industry for 20 plus years as a senior executive in Canada's largest space company. And then in 2018, I had the opportunity to join as CEO of a direct air capture company. That's remember those four categories of carbon and removal we talked about earlier on.

Molly Wood:

All the best people are, Steve.

Steve Oldham:

Air is one of those. So in 2018, I joined what was at the time a very small company called Carbon Engineering up in Canada. It was one of the very early direct air capture companies. We had about, I think, 15 people when I joined. When I left, it was up to 150 people, and the company recently sold to Occidental in the US. It was their partner for building plants. So that kind of got me into the carbon removal industry. The Captura solution I find really interesting. Just the inherent sense of using the ocean with its enormous scale, but doing so in a sustainable way that doesn't impact the ocean. To me, the opportunity to bring the second carbon removal technology to the table, we need lots. But to bring two to the table and show that they're feasible and scalable, that's a very rewarding thing for me personally.

Molly Wood:

And so you're saying you are not now, nor have you ever been a professor of anything. Your explanation skills are amazing.

Steve Oldham:

I am not a professor, definitely not an academic. I'm not a smart guy. The smart guys in our company are the ones that create the technologies. And yeah, we're fortunate in having a great relationship with Caltech at Captura. Got some great people from there. It's a tremendous place. But yes, I'm not the smart academic, I'm afraid.

Molly Wood:

I mean, don't under don't undersell the storytelling. The storytelling matters to Steve Oldham. Thanks so much for the time. I really appreciate it.

Steve Oldham:

Thank you.

Molly Wood Voice-Over:

I’m realizing that maybe a subsection of Everybody in the Pool episodes could fit into the category of drain the tub, I do love a theme.

Ok that's it for this episode of Everybody in the Pool. Thank you so much for listening. Email me your thoughts and suggestions to in at everybody in the pool dot com and find all the latest episodes and more at everybody in the pool dot com, the website. And if you want to become a subscriber and get an ad free version of the show, hit the link in the description in your podcast app of choice. Thank you to those of you who already have. See you next week.