Reversing Climate Change by Pulling Carbon Out of the Air
A startup founded by two economists thinks direct air capture of carbon can be made
cost-effective
By Steven Cherry
23 February 2021

Steven Cherry Hi, this is Steven Cherry for Radio Spectrum.

Let’s face it. The United States, and, really, the entire world, has squandered much of the time that has elapsed since climate change first became a concern more than forty years ago.

Increasingly, scientists are warning that taking coal plants off line, building wind and solar farms here and there, and planting trees, even everywhere, aren’t going keep our planet from heating to the point of human misery. Twenty years from now, we’re going to wish we had started thinking about not just carbon-zero technologies, but carbon-negative ones.

Last year we spoke with the founder of Air Company, which makes carbon-negative vodka by starting with liquid CO2 and turning it into ethanol, and then further refining it into a product sold in high-end liquor stores. Was it possible to skip the final refining steps and just use the ethanol as fuel? Yes, we were told, but that would be a waste of what was already close to being a premium product.

Which leads to the question, are there any efforts under way to take carbon out of the atmosphere on an industrial scale? And if so, what would be the entire product chain?

One company already doing that is Global Thermostat, and its CEO is our guest today.

Graciela Chichilnisky is, in addition to the startup, an Argentine-born Professor of Economics and Mathematical Statistics at Columbia University and Director of the school’s Consortium for Risk Management. She’s also co-author of a July 2020 book, Reversing Climate Change.

Welcome to the podcast.

Graciela Chichilnisky Thank you, Steven. Pleasure to be here.

Steven Cherry Graciela, you have to pilot facilities in California, they will each have the capacity to remove 3000 to 4000 metric tons of CO2 per year. How exactly do they operate?

Graciela Chichilnisky The actual capacity varies depending on the equipment, but you are right on the whole, and the facility is at SRI, which used to be the Stanford Research Institute. They work by removing CO2 directly from the air. The technology is called “direct-air-capture” and our firm, Global Thermostat, is the only American firm doing that. And it is the world leader.

The technology, essentially, scrubs air. So you move a lot of air over capture equipment and chemicals that have a natural affinity for CO2, so as the air moves by, the CO2 is absorbed by the solvents and then you separate the combination of the solvent with the CO2 and lo and behold, you got yourself 98 percent pure CO2 coming out at, as a gas, at one atmosphere. That is [at a] very, very, very high, level, how it works.

And the details are, of course, much more complex and very, very interesting. What is most interesting, perhaps, is the chemists who are used to working with constrained capture in limited facilities—hence volumes—find that the natural chemical and physical properties of the process change when you are acting in an unconstrained area (in fact, the whole atmosphere). You are using the air directly from the atmosphere to remove the CO2. And that’s why it is possible to do that in a way that we have patented—we have about 70 patents right now—in a way that actually is economically feasible. It is possible to do it, save the CO2, and make money. And that is, in fact, the business plan for our company, which includes reversing climate change through this process.

Steven Cherry Yes, so let’s take the next step of the process, what happens with the CO2 once it’s at its 98 percent purity?

Graciela Chichilnisky The CO2—what is perhaps a very good secret for most people—you see CO2 is a very valuable gas and even though it’s a nuisance and is dangerous depending on the concentration in your atmosphere, here or earth, it sells for anywhere between a $100/tonne and $1500 to $1800/tonne. So if you think about that, all you need to know is that the cost of obtaining the CO2 from the air should be lower than the cost of selling it.

The question is what markets would satisfy that. And I’m going to give you a case in which we are already working and selling which we are not working yet. We’re already working with the production of synthetic fuels, in particular synthetic gasoline. Gasoline can be produced by combining CO2 and hydrogen, the CO2 from the air, the hydrogen from water—the hydrogen is produced using hydrolysis—and the CO2 comes from here using our technology. Combining those two gives you hydrocarbons and when properly mixed, you obtain a chemical which is molecule by molecule identical to gasoline, except it comes from water and air instead of coming from petroleum. So if you burn it, you still produce CO2, but the CO2 that is emitted came from the atmosphere in the production of the gasoline and therefore you have a closed circle. And in net terms you’re emitting nothing, using the gasoline that is produced from CO2 and hydrogen—from air and water. These markets, the markets currently in our case, in addition to our synthetic gasoline, include the water desalination market. We work with a company that is the largest desalinated of water in the world, in Saudi Arabia.

And they need a lot of CO2 because the process of desalinating water for human consumption requires the use of CO2. In addition to those two examples, applications, commercial uses, synthetic gasoline and disseminated water, there are carbonated beverages, for example, beer and Coca-Cola. Indeed, we work with Coca-Cola and we work with Siemens, and with AME, automobile companies such as. Porsche, to produce clean gasoline—the synthetic gasoline I mentioned.

From the CO2, you can actually produce elements of cement and other building materials. So as a whole, McKinsey has documented that there is a $1 trillion market per year globally for CO2. So CO2 is a very valuable chemical on Earth, even though it’s a nuisance and dangerous in the atmosphere. So the notion is—the notion of Global Thermostat is—bring it down. In other words, take it from the atmosphere where it is dangerous; bring it down to earth, where it is valuable.

Steven Cherry I love that our first carbon negative podcast involved vodka and our second one now involves beer. So that’s the economic case for what you’re doing. There’s also the question of the carbon budget. There’s a certain amount of energy used in the processes of removing CO2 from the air and then using it for some of these applications; what would be a typical net carbon budget?

Graciela Chichilnisky Negative, in other words, what happens is that we don’t use electricity, which is mostly reduced from fossil fuels right now. We use heat and our heat can be produced as a waste heat from other processes; it doesn’t have to be electricity. In fact we use very little electricity.

But think of it this way: In the year 2020, we for the first time in history humans are able to produce electricity directly from the sun less expensively than using fossil fuels. The two-and-a-half cents or less, continually downward, is the going price for solar photovoltaic production of electricity. It’s the lowest cost. Two cents a kilowatt hour is really the lowest possible cost.

Steven Cherry One wonderful thing about this is that you’re an economist and so you’re determined not just to develop technologies, but ensure that they find a home in the marketplace because that’s the most practical way to implement them at scale.

In 2019, Global Thermostat started working with Exxon Mobil. I understand they provided some money and I believe initially 10 employees. I gather the idea is for them to be one organization commercializing this technology further. How would that work?

Graciela Chichilnisky Well, first of all, I do have two Ph.D.s; I started pure mathematics at MIT. That was my first Ph.D. My second Ph.D. was in economics at UC Berkeley. So I do have the mathematics as well as the economics in my background. What we’re doing requires several forms of expertise. You said it; Global Thermostat has made a joint development agreement with Exxon and is working with Coca-Cola and is working now, with Siemens; is working with a company called HIF, which is in Chile.

So, how does that work? As you probably know, Exxon Mobil is a multifaceted company. In addition to fossil fuels, they have a huge expertise in carbon capture technology, the old fashioned, I would say traditional, type. And by that I mean capture of CO2 from the fumes of power plants, for example.

They have the resources and the know-how, and we are a small company and we want to expand our production. So they offered an opportunity for us to go with the high-level technology, the advanced company in the area of carbon capture in a more traditional way that are willing to experiment and they’re willing to advance commercially the removal of CO2 directly from the atmosphere.

So that with them in our contract, we intend to build a one gigaton plant, that’s what we contracted to do, which means that we then we will scale up or technology. So every year it can eventually remove one billion—with a ‘b’ as in boy—tons of CO2 from the atmosphere every year. That’s the scale-up I’m talking about, and that is the main purpose of our partnership with Exxon Mobil.

And if you think about it—you said it yourself—you want to know what the carbon budget really, roughly speaking, don’t forget that I worked in the Kyoto Protocol. And I created the carbon market of the Kyoto Protocols. So I know a lot about carbon budgets and how demanding they are and how far we are from what we need to do. We need to essentially remove 40 gigatons of CO2 every year from the atmosphere in order to reverse climate change. And what I’m telling you is that we these type of partnerships with companies like Exxon, we can do one gigaton—you’re at a shooting distance from that goal. And that’s why I a contract with Exxon is to scale up our technology to remove one gigaton of CO2 per year. And then if we had 40 of those plans, then we would be removing all the CO2 that humans need to remove from the atmosphere right now in order to reverse climate change.

Steven Cherry It seems paradoxical that it would make more sense to take carbon directly out of the air, the direct air capture, rather than focusing on concentrated sources of carbon and carbon dioxide, such as a power plant smokestack. How is that paradox resolved? How is it more sensible to take it directly out of the atmosphere?

Graciela Chichilnisky First of all, it is not sensible, it’s very creative, very unique, and he has never been done not what we’re doing—it has never been done. And there is a good reason why wasn’t done, because as you’re point out, it’s more difficult, actually, and it’s more expensive to remove CO2 from the air than to remove it from a concentrated source. So why would we be doing that? The answer is, if you remove CO2 from the chimneys or any natural facility, the best you can do—the best best best possible—is to make that facility carbon neutral; to remove all the CO2 that it is emitting.

That’s the best. If you’re really lucky, right? Okay, that’s not enough anymore. When I used to be the lead author of the IPCC, the Intergovernmental Panel on Climate Change, working on this topic, I found—and it is well-known now—that going carbon neutral does not suffice. I think you say that in your introduction. Now we have to go carbon negative, which means we have to remove in net terms more CO2 than what is emitted. And that CO2 that we remove should be stabilized on Earth. I’m not saying sequester on the ground, but I’m saying stabilized. You know, it could be in materials or instruments or whatever, stabilizing nerves after it’s removed.

If you need to remove more CO2 than what you emit and we need to remove 40 gigatons more than what we emit right now, you cannot do it from industrial facilities, the best that you can achieve is carbon neutrality. You need to go carbon negative. For that you have to go and remove CO2 from air.

Steven Cherry I said that 20 years from now, we’ll wish we had started all this 20 years earlier, but you actually started this process a decade ago, you already foresaw that we would need carbon negative processes. But at the same time, as you mentioned, you were also working to develop the Kyoto Protocols, specifically creating carbon markets. Was that just a stopgap before getting to this point that you’re at now?

Graciela Chichilnisky No. No, no. The carbon market solution was the solution, an easy solution. Let me explain. The problem is that our prices are all wrong, and when we try to maximize economic performance, we maximize our GDP, in which we don’t take into account the enormous damage that excessive CO2 emissions are causing to humans to our economy, to our world, and even to our survival as a species. So the invention of the carbon market—I invented and I designed it and I rolled it into the Kyoto Protocol in 1997—was done with a purpose of changing the system of values.

In other words, introducing prices and values that make it more desirable to be clean rather than to over-emit. Right now if we were to cut all the trees in the United States and produce toilet paper, our would economic system of economic performance, how we measure it, we say that we are much better off. After all, more trees are being cut off and used to produce toilet paper than before.

So I decided that this had to change. And in fact, when I designed and created the carbon market, in the Kyoto Protocol, it became international law in 2005. And it is now what’s called the European Union Emission Trading System, which encompasses 27 nations, and is also used in China, in 14 states in the United States, and essentially 25 percent of humankind is using now the carbon market, that I designed and wrote into the protocol originally in 1997. But the most important statistic for me is, in December 2019 Physics Today, there is an article on the carbon market, which says the carbon market has succeeded by decreasing the emissions from the nations that use the carbon market in those years since 2005, when it became international law, decreasing the emission, those nations that use the carbon market by 30 percent from the base year.

Another way of saying is that if the whole world was using, not just the 25 percent that I mentioned, the carbon markets, we would be 30 percent below the level of emissions of 2005. And you know what? We really wouldn’t have the climate disaster, the catastrophe, that we fear. We would not have it because we would be containing the emissions of CO2 through the use of the carbon market, as was done in all the nations that adopted carbon market when it became international law in 2005.

So that’s a solution, but we haven’t adopted it, only 25 percent of the work succeeded. The rest of the world went south. We emitted even more. So now in relation to decreasing emissions because you cannot avoid increasing emissions—that’s critical—you now have to remove the CO2, the legacy CO2, that we put into the atmosphere and which is still in the atmosphere after all these years. So from the physical point of view, you have to know CO2 doesn’t decay, doesn’t decay as fast as other gases, and it remains in the atmosphere once emitted for decades, even hundreds of years in some cases. As a result of that, we do have a lot of legacy CO2 that doesn’t decay.

Steven Cherry The title of your book is Reversing Climate Change. The subtitle is How Carbon Removals Can Resolve Climate Change and Fix the Economy. Perhaps you want to say another word about the fix the economy part.

Graciela Chichilnisky Yeah, I will do it with two sentences. Sentence #1, I just want to quote new President Biden, who said, “When I think about climate change,” he said, “I think jobs, jobs, jobs.” So a technological evolution of this nature, that could be even a revolution, it’s creating a lot of jobs and it is creating the infrastructure that will allow us to solve the problem and grow the economy at the same time, because every time you remove CO2, you make money now. It doesn’t cost money. You have to invest initially, but you make money.

The second issue—[Biden] doesn’t address because he doesn’t know the level of detail or this type of focus—is the problem of the environment and the resources is very closely tied with the problem of inequity. And you must be aware, because there have been a number of books that were really prominently published and reviewed about the increase in the inequity in the global economy, not just internationally that we know is huge, it has increased 20 times since 1945, but also within nations, like in the United States. Well, what’s interesting is that these new technologies not only solve the problem at the technological level and not only can bring jobs, as I mentioned and I quoted Biden saying so, but in addition, these technologies sponsor equity. And I will give you two examples very quickly. As I mentioned already, the solar photovoltaic revolution in which 80 percent of the cost of the production of electricity for photovoltaic energy has decreased in the last 20 years.

That revolution has created the most accessible form of energy than ever before, because while fossil fuels were the main raw material for the production of electricity in the $60 trillion power plant economy, those are really not very equitable at all. And fossil fuels come from a few regions in the world. They have to be extracted from under the earth, etc. And the result is that our whole energy production system lies at the foundation of the inequity of the modern economy, the industrial revolution. If you replace fossil fuels, natural gas, petroleum, and coal, by the sun, as an input, you have a major equalizer because everybody in the world has access to the sun in the same amount. So the input now is no longer fossil fuels that come from a few places that make a lot of money. The input now is the sun that comes from everywhere and everybody has access to that. They import. That creates energy. Now, that’s more equitable is a huge difference, huge difference.

And the other difference is that with new technology that transforms CO2 into materials for construction or even into clean forms of energy like synthetic gasoline as I explained before. That is based on air, as an input, and the air has a property, it has the same concentration of CO2 all over the planet and this means an equalizer again. So we now can reduce cement, let’s say, beverages, food. You can even reduce protein from CO2 of course, because of the carbon molecules; you can actually produce all the materials that we need and even food and drinks, beverages, from air. And the air is equitably distributed—it’s one of the last few public goods that everybody has access to, as is the sun. So we are now going into a new economy. Powered by sun and with resources coming from air and, you know, what? That solves the problem of equity in a big way. I would say inequity, which is so paralyzing to economies and to the world as a whole. So I wanted to say not only this is an environmental change, some may say a revolution, but this is in addition a social and economic change and some would say revolution.

Steven Cherry Yeah, we could do we could do an entire show on things like the resource paradox, countries that are rich in oil, for example, end up being poorer through the extraction processes than when they started. Well, Graciela, it’s going to take economists, businesspeople, scientists and politicians to lead us out of this crisis. And we’re fortunate to have a news, someone who is several of those things. Thank you for your research, your book, your company, your teaching, and for joining us today.

Graciela Chichilnisky Great. Thank you very, very much for your time and for your insightful questions.

Steven Cherry Well Graciela, it’s going to take economists, businesspeople, scientists, and politicians to lead us out of this crisis, and we’re fortunate to have in you someone who is two of those things working with the other two. Thanks for your research, your book, your company, and your teaching—and for joining us today.

We’ve been speaking with Graciela Chichilnisky: Columbia University economist, co-author of the 2020 book, Reversing Climate Change, and CEO of Global Thermostat, a startup devoted to pulling carbon out of the air cost-effectively.

Radio Spectrum is brought to you by IEEE Spectrum, the member magazine of the Institute of Electrical and Electronic Engineers, a professional organization dedicated to advancing technology for the benefit of humanity.

This interview was recorded February 2, 2021 via Zoom and AdobeAudition. Our theme music is by Chad Crouch.

You can subscribe to Radio Spectrum on Spotify, Apple Podcast, and wherever else you get your podcasts, or listen on the Spectrum website, where you can also sign up for alerts of new episodes. We welcome your feedback on the web or in social media.

For Radio Spectrum, I’m Steven Cherry.

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