Carbon-negative Technology To Solve the Climate Crisis - Eli Yablonovitch

Carbon-negative Technology To Solve the Climate Crisis - Eli Yablonovitch

Show Video

(attendees applauding) - Okay, it's great to be here, and to have the opportunity to describe how we're going to solve the carbon dioxide crisis. I should mention my co-author, Harry Deckman. And a long story we've been working, well, we started working together 45 years ago. Okay, so let's get right into it. It used to be all about being carbon neutral.

And now there's a recognition that carbon neutral is not enough, and that we actually have to have carbon dioxide removal. We have to have what might be called carbon negativity. Now, I'll give you some of the quick reasons. When you take a flight to another continent, the amount of time your airplane can stay in the air is determined by the energy to mass ratio of the fuel. And the jet fuel is the highest energy to mass ratio, so we use it.

And with jet fuel an airplane can stay aloft for 19 hours, and that explains the longest flight. There's an interesting physics question at the, let's say it's maybe at the level of a very good senior in physics, and go from the energy to mass ratio, from that figure out that the longest flight is going to be from Dallas to Singapore, which it was for a long time. Now, so, that's not easy to replace. We're gonna be putting CO2 into the air if we do that, and we're gonna have to have a way of getting it back out.

So another important factor is summer winter energy storage. And that is to say that it's great to have batteries, at least it takes care of the nighttime when the sun is not shining. But the real challenge is to move energy from the summer when we have lots of sunlight and our solar panels are working very well, to move them to the winter. And this is very difficult to do because the... You get to use this once a year. So the capital cost has to be incredibly low.

And you compare that with, let's say, oil tanks that are used, for example in the Northeast for heating oil, and the just storing the oil for just once a year like that, you still, you only add a penny or two to the cost of the oil. And so that's a very tough challenge to achieve that. We don't have a good energy storage. Good, I say it's one of the great unsolved problems in the energy business, is seasonal energy storage. But oil does that very easily. And then the third thing is that there will always be countries that do not cooperate.

And the idea is not to go to war with these countries, to pull their carbon dioxide out of the air, and then send them a bill. And then you argue about the bill, okay? So I think recognition that carbon in the atmosphere will continue to grow unless we extract it. And then there is a fourth reason I have here, is that in some climate models, positive feedback of CO2 from permafrost can lead to a thermal runaway. And so we may already have gone too far, and we definitely need to have a way of pulling carbon dioxide out of the atmosphere. So carbon neutral used to be a big thing, but I think it's widely recognized now that carbon dioxide removal is needed. So how do you do it? Well, there have been a bunch of reports on this.

People have started recognizing this. About five years ago I was on a panel of the American Physical Society, and they didn't wanna talk about carbon dioxide removal. They just wanted to be carbon neutral. And, but they now, then they started, okay, so about five years ago, carbon dioxide removal became a thing. And then the same thing in Europe, of course they don't wanna be left behind. They have their own advice science advisory council, and they called it negative emission technology.

And then an article appeared in Physics Today. So in the past five years, carbon dioxide removal has become a thing. And there have been recent reports, I think that the government is spending $1.2 billion

that they announced a couple of weeks ago, that they're gonna pull carbon dioxide out of the air, which is kind of hard because you have to sort of pass the entire atmosphere through some pipes. And so it ends up costing a lot. The latest price is $1,000 per metric ton.

And so that's actually a lot. Actually I should calibrate prices 'cause people don't normally go to the market to biometric ton of CO2, but let's say we talk, so I'm gonna show you, we can get down to $60 a ton. And how much is $60 a ton? It's obviously a very low price in relation to other prices.

But if you can convert it to gasoline, so let's say you burn some gasoline and you... You generate some CO2, and then you pull that CO2 outta the air. So a challenge for the advanced placement high school chemistry, convert $60 a ton to a certain number of dollars per gallon.

And so it's just a conversion of units, and it works out to be 53 cents a gallon. So to give away the punchline, we're gonna get down to 53 cents per gallon of gasoline. And the current prices are more like $6. You can see that the 53 cents is a very tolerable price, although it's still adds up to quite a bit of money. And at the prices of $600 a ton, would be 10 times higher, $1,000 a ton, even higher. It would really reduce standards of living.

Okay now, what's in the European report? So they try to include everything. They wanted forestry and reforestation. They want to convince farmers to change the way they farm and to increase the carbon that's in the roots of the soil. There is a concept to use of biofuel, and I'm gonna be talking a lot about biofuel 'cause it's very close to what we're talking about. To burn the biomass, and then capture the smoke, and pump it underground. So that's called BECCS, bioenergy with carbon capture.

There's weathering, this kind of interesting. There are rocks that actually absorb carbon dioxide, but it's very slow. So you spread, grind up the rocks and spread 'em all over the earth's surface, and it's still not enough.

It's a very slow process. Then there's the direct air capture that I mentioned that costs 600 to $1,000 a ton. And then there are more exotic ideas, like fertilizing the ocean.

So you could create a green marine algae, and then you somehow you prevent, you hope that the algae falls to the deep ocean where it'll stay. But it's actually, that's a lot of questions with regard to that one. Now, the one thing that is missing in this list, the most obvious thing that is missing, is simply the burial of the biomass, which we call Agro-Sequestration. Now who came up with this idea? First is a very famous physicist by name of Freeman Dyson. And in 1976, he had already proposed that we grow biomass, actually had mined trees, and we tossed the trees underground, and we'll pull, and that you can actually do that and you'll definitely pull carbon dioxide out of the air. But it has a little problem that he didn't include.

And that is that when you throw biomass underground, it decomposes and get your carbon dioxide back, and with some methane, which is even worse. So that's no good. But the idea of carbon dioxide removal is now more or less accepted and there is an XPrize, $50 million for the winner. And some consolation prizes have already been awarded.

Now why is it difficult to pull carbon dioxide out of the air? Well, one of the things is that the carbon dioxide is present at a very low concentration. And if you want to concentrate the carbon, you have to supply energy. So think of it as the plant is carbon, and you're pulling it from the air. It's takes a just a crude calculation, says it'll take about a quarter of an electron volt. At absolute minimum, they'll take a quarter of an electron volt.

You need energy. And of course if you grow plants, the plants take sunlight, converted energy, and are able to concentrate the carbon from the atmosphere. So which plants should we grow for this purpose? Fortunately, the biofuel people have worked this out. Biofuel was extremely popular about 15 years ago, and they did very detailed studies.

What is the best vegetation in different parts of the world? And in Midwest it's Miscanthus. And in Florida, it's this thing called Napier Grass, et cetera. So different forms of crops in different parts of the world. And they also figured out the yield, and the cost of the agriculture and so forth. So these are some of the crops, switchgrass and so on, and elephant grass, some people still think about algae.

Okay, now the important thing is the productivity. Every nation in the world publishes its agricultural statistics, which is how much they produce, the average productivity of the land and so forth. Now, these particular crops are not very useful as food.

They're the essentially cellulose, and they... It's not food for insects. And so because of that, it makes the farmer does not need to use insecticides as much, and the productivity is higher for cellulose than it is for something really useful like food. Okay, so, I gave this talk in Europe, and I started using the word maize because they don't understand what corn is. Okay, but if you're growing cellulose, you get up to three times more productivity than if you're growing a food crop like corn.

And the cellulose itself is about 44% by weight carbon. And so you work this out and you can figure out how many tons of carbon you can pull down, et cetera. So it's quite effective. Now, I was very strongly influenced in my early career, I think Jeff mentioned, I used to work on solar cells, and I was influenced by this gentleman, Al Rose, who was a leader at the RCA laboratories. And people have to be my age to even remember what RCA was.

It was a very important company, created television, created broadcasting, created advertising. It started right after World War I. And, but he was a consultant and I was sort of like the new kid. And so he was kinda like my mentor, and he tells me, "Eli, why don't you go figure out what is the dollars per megajoule in gasoline, and then get the Wall Street Journal and look up the dollars for a bushel of corn, and then convert the corn to dollars for megajoule, and figure out what is the dollars for megajoule of corn versus the dollars for megajoule of gasoline.

And tell me the difference in price." So he was teasing me a little. And because he had already worked this out, I didn't realize he had already published it in this paper. But I went ahead and did it. And I was shocked to discover that the energy price of corn was pretty similar to the energy price of gasoline. Of course it was during an energy crisis, but it was still kind of amazing.

And ever since then, I have had tremendous respect for agriculture. And so what are we gonna do with all this biomass? Is we're gonna put it underground in an environmental chamber and keep it dry. That's the important thing that is new, and what I'm gonna tell you, is if you keep the biomass dry, it'll sit there and last for millennia. And that's sort of the missing link in carbon dioxide removal, what are you going to do with the carbon.

So we went ahead and we published this paper, analyzing this thing, and of course I'm gonna show you some of the things that happen. Now, of course, we've heard a lot about biofuel, used to be a very big thing at the Lawrence Berkeley lab. Let me mention some of the pitfalls of biofuel.

Let's say you grow cellulose as is recommended. And this is like the strong point of the biofuel. They analyze that in great detail. But look at the formula for cellulose. The approximate formula is CH2O. And what it means is that the carbon dioxide is already half-oxidized in the biomass.

So unfortunately, what that means is that, you have to go twice as much biomass because it's already half-oxidized, okay? Versus simply burying it, in which case you get rid of all of the carbon when you do that. So the biofuel requires twice as much farming than simple burial. And there's many other problems with biofuel. The conversion to fuel is very capital intensive, et cetera.

So what happens if you do simple burial? The biomass decomposes, and you could be anaerobic, doesn't help, because there are anaerobic bacteria that will digest your biomass and convert it back into CO2. So the insects, the fungi, the microbes, they go back. And worse than CO2, they also produce methane. So you've gotta do something about it. Now if you don't, you get the proportion of CO2 and the proportion of methane.

Now what's very popular out there, is the simple burial of wood. And there are at least, that I made a list or at least seven companies. Well, I know the name of the company, and I know the website that are just bearing wood without any precautions. And they have reason, they can say, "Well, it might be okay." The problem is that wood is about 70% cellulose and 30% lignin.

And lignin is the part of the wood that makes the beautiful grain that we enjoy in the appearance of wood. Now, lignin is very difficult to do any with in, And it's the bane of people who want to do biofuel because the lignin is so stable, it's very hard to convert it into anything. But the cellulose decomposes very readily. And so I wonder if you've had this experience where you're digging up in your backyard, and you're trying to plant something and there's a board buried down there, okay? That the contractors left behind when they built the house.

And so you dig the board out and it feels okay, it looks like a board, but it has almost no weight to it. And the reason is that the cellulose is gone. And what you have is the lignin in the shape of a board.

And you see this sometimes in museums. You have things dug up from the ocean or harbor. I remember we go being in a museum in Stockholm, and they had a ship from the 1600s, but you can be sure that the weight of the wood was a fraction of the original weight 'cause it's the lignin that that lasts long. So what happens is that you can't say that it's useless to bury the wood because you're getting 30% of the original carbon is sequestered, but 70% is gone and it completely messes up the economics.

So the lignin provides strength to the wood, has many other things, and only 30% of the weight of the wood is sequestered under those circumstances. So I can't say it's useless, but it's not very cost effective. So we need to solve the problem of the decomposition of the biomass. And so this idea has been around, at least since the 1970s with Freeman Dyson, the idea of burying biomass.

But how to prevent it from decomposing? So I have to introduce a scientific concept called water activity. So water activity is just like relative humidity, but it applies to things that are solid. For example, you wouldn't ask what is the relative humidity of a piece of steak like this, but it's perfectly sensible to ask what is the water activity inside the steak? And indeed, if you dry the meat, dry it very thoroughly, it becomes very stable, doesn't decompose. So all biomass has a certain water activity, but if the biomass is very dry, it'll have a low water activity, which you can read that that's like relative humidity.

And the microbes that decompose the biomass, they need a certain amount of water. And indeed it has been discovered that all living things require some water just to move the chemicals around inside the cell. But if you have less than 60% water activity, the metabolism comes to a halt. And so who has studied this? First of all, let me, I have another picture here. This is like the Native Americans drying, in the Pacific Northwest, drying the salmon. So what happens is that as you reduce the water activity, fewer and fewer forms of biology can survive.

Now the bacteria go away early than the yeasts, then the mildews, and more bacteria, and so forth. And finally, at 60% water activity, metabolism stops. What's going on there is something that has been investigated, it's been investigated by two agencies of the government. The first agency is the Food and Drug Administration.

Let's say you want to put some food on the shelf and you have it nicely wrapped in cellophane. And the inspector comes and says, "Well, is it dry?" And they say, "Yes, the water activity is less than 60%." He says, "Okay, seal it up and put it on the shelf." Because it's safe. There's not gonna be any decomposition or bacteria growing, or other things if it's less than 60% water activity.

The other federal agency that studies this in great detail is NASA. They're looking for life on other planets. And they're asking, "Well, how much water do we need to have life on other planets?" So they arrive at the same conclusion. You need at least 60% water activity in a solid material to support the metabolism of the microbes. So then, you look at what the biomass does.

So on the horizontal axis, I have plotted water activity. So you gotta be to the left of this line, so that you have low enough water activity. And if you dry the biomass sufficiently, you can get there. So this is a graph that tells you how much weight, percent of water you need, to get the water activity below 60%. And it's roughly 12 to 14 weight percent of water. And that's enough to prevent decomposition.

And by the way, you look this up on the Chicago Board of Trade, if you're a farmer and you wanna deliver your crop to the Chicago Board of Trade, they have a requirement. They don't want to pay for too much water. So they have a requirement, the weight percent water has to be below 14%, and that actually gets you below the threshold for water activity. And they can put the corn on a ship and take a long trip, and it's fine. So this is the concept we have in mind, is to put the dry biomass in an environmental chamber, underground, seal it with four millimeters of polyethylene. So that's a very substantial thickness of polyethylene.

And the first thing to mention is how much land do we need for this? And the amount of land for the environmental chamber is 1/10000th of the land required to grow the biomass. So you would set aside this land, you would bury the biomass in this chamber underground, and then you throw dirt on it and it becomes agricultural land again. So you're not losing the land, but you're pulling carbon dioxide out of the air. This is stable for greater than 10,000 years because four millimeters of polyethylene, polyethylene really does not like water.

Water barely diffuses through it. It's been studied and the groundwater diffuses it less than two microns a year equivalent to liquid thickness. And because of the biomass is dry, it can safely absorb that and not have any, not get above 60% water activity.

So now let's say we wanna pull the carbon dioxide out of the atmosphere. So I have here a bunch of numbers, but basically if you can pull 20 gigatons of CO2 out of the atmosphere, that would compensate for what we burn. Of course we burn a lot of stuff that we shouldn't be burning at all.

And so this is a little bit of an overestimate. Now, so we're weighing at the land for growing that much biomass. Again, we fall back on the biofuel people, they have already worked out where to grow all these biofuel props. And so here's a report and published in science, here's one from the Department of Energy.

And looking at where we would get the land, and I can sort of summarize it in this slide. How much land would you need to pull the annual carbon dioxide out of the air? So we used this horizontal bar is all the land that's available. And of course at the north and south pole, it's a lot of it's covered with ice. And then you go down and you say, "Well, there's quite a bit of agriculture, there's forestry, there's other things."

Now in the agriculture you have the row crops. So this is like what we think of as the Midwest. You have row crops, soybeans, corn, wheat, et cetera. But most of the agricultural land is just pasture. Now the quality of land needed to grow the biomass is sort of similar to the pasture land, and the amount of land that would be needed is represented by this blue bar.

So it gives you an idea that yes, we can pull out the existing, the annual carbon dioxide, we can actually pull that out and it would be a very substantial new cash crop for farmers. But it is something that is doable. And fortunately because agriculture is so efficient that we've been doing it for 10,000 years, the cost actually comes out to be pretty moderate, even though it would be a big new agricultural crop. So let's talk about the cost. So what we're gonna do is look at these non-food crops and these biofuel crops, and figure out what it's gonna cost.

There's a number of different ways of doing it. You can go bottoms up ahead of all the things that a farmer has to pay for. And... There's another way of doing it.

You can look up the cost of an acre of farming, or you know, the productivity of land. You look that up, and the Chicago Mercantile Exchange, and you figure out that the farmers are, at least most of the time they're not losing money. So they're breaking even. And it's about $500 an acre.

And then from that, you can figure out what the productivity of a biofuel crop would be. And it's easier to farm the biofuel than to farm actual food. And so the cost, this is what the cost works out to be. And it's pretty much a very solid estimate. It's roughly, this is for different plants, miscanthus, switchgrass, some people like pine trees, and it's about $30 per metric ton of the CO2, just for the agricultural part. And switchgrass a little more, for the wood, it's a little bit more.

And then you ask what is the cost of building the environmental chamber? So the environmental chamber is existing technology because this is used to store our garbage. They actually, and our various hazardous things that we generate in our labs here on campus. And it ends up being sealed off by four millimeters of polyethylene. The design is pretty similar in that case.

We don't want the groundwater to be contaminated. Of course in our case, we're doing it in reverse. We don't want the groundwater to make our environmental chamber wet, our biomass wet. And now they build these, you can get a contractor to build it, and the price is known and it's also works out to be about $30 a ton. So the total cost is about $60 a ton for this form of carbon sequestration, which as I mentioned translates to 53 cents a gallon of gasoline, and would take care of 20 gigatons of CO2.

And we know roughly what it's gonna cost, is $60 a ton. And the world GNP is $100 trillion, and this is going to cost $1.2 trillion. So it'll be a setback to the world economy of 1.2%. Now productivity grows more than 1.2% a year.

So it would be like half a year setback in world productivity. And so I think this gives us a little bit of perspective. Two things on this slide perspective. Are you willing to pay 53 cents extra for every gallon of gasoline? And what's the overall effect on the world economy? And it's pretty small. So I have to tell you one more thing.

So we sent the paper off for publication and the referee comes back, and says, "Well this is all well and good, but you need a natural experiment. Some kind of proof that if you keep the biomass dry, it's going to last for a very, very long time." And so we had it, we didn't think it was necessary, but I think it was a good point. So it was an experiment, was not a natural experiment. It was actually a human experiment made by people and had a little bit to do with politics of 2000 years ago.

So 2000 years ago in Israel, they had King Herod. And like most kings, he was afraid of being overthrown. So he built a palace, a castle if you like, a defensive castle on top of this mesa in Israel, which a very famous mesa because this mesa was the last holdup of the Jewish zealous against the Roman legions. The Dead Sea is in the background. Dead sea used to be right up to the base of the mesa.

The top of the mesa is actually at sea level. And here is King Herod's palace. And it's on a series of levels here.

And it's a very remote place, hard to get to. You can see the vertical walls are very good for defense. And it was sort of forgotten for 2000 years. And then something interesting happened, and that is that an archeologist in 1965 starts excavating. So this is a likeness of King Herod the Great and he builds a castle in about 2000 years ago. And in 1965, an archeologist goes and digs it up, and he writes a bunch of archeology papers on it, about the ancient past.

And in the course of doing that, he discovers some seeds, you can see they're the size of pecans, and these are seeds of the date palm tree. And then in 2005, a medical doctor from a hospital in Jerusalem hears about this. And by then, the archeologist has passed away, and she is able to persuade the people who hold all these archeological treasures, "Can you please give me some of the seeds? And I'll have them carbon-dated." So she has some carbon-dated, and they turn out to be 2000 years old. And then she gives them over to a horticulturalist. And the horticulturalist plants them in 2005, and they germinate.

And so they germinate, they have a little pot, and they grow a little bit more and they put 'em in a bigger pot. And finally you get to today, and you have a tree that's 18 years old. It has ended up as being figure five of our paper. The tree is 18 years old, and it was germinated 18 years ago from a seed that was 2000 years old.

And so this gives you an idea, yes, if you keep things dry, it is one of the driest places in the world. If you keep things dry, then you preserve it for a very long time. So this is actual proof that this works.

So I think my story could end there. But I wanna tell you one more thing about agriculture. I mentioned that I'm very fascinated with agriculture and so you can do a lot of studies. Let me mention some data that's been collected since 1960. The yield of wheat has doubled in the least developed countries.

So that's kind of interesting. I'll show you some more data. This is a remarkable data from England.

There's data going back to the 1700s, how much wheat is produced per unit of land. And in those days they did not have acres. They did not even have bushels. You have to convert the units. But so we started the graph at 1800, the year 1800.

It was also roughly the time of Malthus. Malthus said that the industrial revolution is pointless 'cause everyone's gonna starve 'cause they'll have more children than we could produce food. And he was wrong. And this is one of the reasons he was wrong. If you look from 1800 to 1900, the productivity of the land doubled.

And then in 1905, the making artificial, the Haber process for making artificial fertilizer was invented. And so we, it went even faster. So from 1900 to 1950 it doubled. And from 1950 to 2000 it doubled again. And so what it says is there is indeed a Moore's law for agriculture.

It's not as fast as the regular Moore's law, but agriculture gets better and better every year. And we can expect it to continue into the future, at least as doubling every 50 years. Why? Because we now have CRISPR, we have other ways of manipulating the genome and there's a lot of room for improvement. Here's a factoid, is that corn is only 2% efficient. Growing corn is only 2% efficient. And even these fantastic biofuel crops are maybe 4 to 5% efficient.

And so there's lots of room for improvement. The processes and the photosynthesis are very similar to the processes in solar panels. And the solar panels are up to 29% efficiency for a flat plate panel. So we have probably another three factors of two left to go, using CRISPR and other improvements. And here's another data point which is somewhat surprising, is that a very large amount of land has fallen out of agricultural production. I think what they mean is row crops.

A lot of this has been turned into woodlots, but we are today using 68% less land to produce the same amount of food. So this is interesting and it projects out to very big improvements in agriculture in the future. However, we have not used any of these future improvements in the cost analysis. These, the $60 per ton is using present day agricultural methods. So what do we need to solve the climate crisis? We need something scalable.

Well, agriculture is one of mankind's largest industries and it is scalable. It's already very large. The cost is modest, 53 cents a gallon of gas, 1.2% of a world GNP over the next century. Now, here's something that's very important.

Is it really stable? Because society's gonna do something big and spend $1 trillion a year, and then well, we'll find out in a hundred years maybe it wasn't done right? So we need to have a proven sequestration method. And the dryness has been proven to work for over 2000 years in that experiment. That not an exactly an experiment attempt by King Herod to protect himself, okay? And then we need predictability. We can't really wait hundreds of years for validation and we need rapid implementation. So the implementation can begin in the next growing season, let's say April of 2024, which means by January, we would need to start contracting with farmers.

Actually, they're already growing the miscanthus, but we need them to increase the amount that they're growing. So I'm just about done. I just wanna say I'm a high-tech guy offering a low-tech solution. Actually agriculture is not low-tech, it's getting higher-tech all the time.

But nonetheless, we can't really take risks. No one's gonna take a risk with this. We can't really wait hundreds of years to see how things turn out. And Agro-Sequestration is essentially a proven method.

So where are we gonna get the land? Of course, I already told you there's plenty of land available, but 40% of US corn is already used for ethanol, which is not even carbon neutral. It's actually a bad thing to do. And so imagine taking 40% of Iowa and using it to grow miscanthus. Of course the farmers will be very happy, so it gives them a new cash crop.

And so that I think is something that we could start right away. And it does appear to be the lowest cost carbon dioxide removal technology, and it could even remove historical carbon emissions. But we have to avoid complacency and we need to research new forms of energy. We need to continue with conservation, alternative energy, de-carbonization, et cetera.

All these things, we need to continue, we need an all-of-the-above approach. So to implement things, I've learned that you, to get anything done, you really need to do it inside a company. So we have actually started a company called AgroCapture Corporation, and we're recruiting at all levels from members of technical staff, all the way up to CEOs. So please contact me if you're interested.

So this is my final slide. We all know we're living in previously uncharted carbon concentration in the atmosphere. I think it's recognized now that carbon neutral is not gonna be quite enough. We need to have carbon dioxide removal technologies and Agro-Sequestration can do this. And let me thank you for your attention, and hopefully get some questions here.

Thank you. (attendees applaud) (staff member distortedly speaking over microphone) - [Moderator] Okay, we're open for question. We here, this we have someone carrying microphone. There we go. - This is really spectacular.

I'm much more optimistic about the future of our planet when I hear you talk about this stuff. In the papers, you mentioned that in this burial thing you'll add salt. And I'm curious about that because the 3000-year experiment I finally think that was using salt.

- That's correct. - Do you think the experiments with salt, is that something you're concerned with? - The salt is kind of an interesting alternative option. You can make things dry with salt, you can preserve food with salt. And the mechanism of preservation is you're pulling the water out with the salt.

But it's just a trade off versus the cost of drying. So drying has a certain cost. We've included that in our cost estimates.

And the salt would be another way to do the drying. But I prefer not to talk too much about the salt because it's just an option on a part of the process. And you don't have to do it, that you can just dry the biomass efficiently. But thanks for reading the papers. (chuckles)

- [Bill] Hey, Bill here. Did they cost us, would include the cost of water? - The... What we envision and what has been worked out by the biofuel people, is that there is land with like ranch land that for these types of crops, that there is adequate precipitation on those lands to grow these types of crops. And we took into account all the costs of the agriculture. So for example, one of the things that comes up is the carbon efficiency, says, well you're sequestering a hundred tons of carbon, but your farm machinery produced a few tons of CO2, and your trucking, the stuff around also produce CO2, and then the fertilizer produced a little bit of N2O, which is similar to CO2, and it's a bad thing.

And all of those things together add up to about 5%. So we have about 95% carbon efficiency. Now, some would argue that we have over 100% carbon efficiency because we're putting roots deep into the ground, and that's so not including that carbon, but if you start including that stuff, we could even go over 100%. So that's roughly where all the other factors lie.

- [Audience] So Eli, fascinating work. Tell us a little bit, without disclosing confidential information about the business model of a for-profit company, would it depend on a carbon market to make money? How would that work? - Yeah. What's going on right now is that many large companies, and just household names have decided to pull their assets together, and they have created a company called Frontier Climate. And they give the money to Frontier Climate, and then Frontier Climate buys the carbon.

And so a company in this, and there are many companies in this business, and they would have to persuade the Frontier Climate that they have a good method of sequestration, and Frontier Climate will then pay them for the carbon credits. But what the payments are ridiculous. They're well over $600 a ton of CO2. So, and in fact they're paying, they're not paying on delivery of the carbon or the sequestration, they're paying in advance, which is a pretty good deal from the business viewpoint.

But these companies have, maybe for public relations, for purposes or for whatever reason, they have budgeted $20 billion to buy carbon credits. And that would be the initial thing. Now ultimately, if you ask me where is this gonna end up, I think it's going to end up with a mandate. The mandate would be you put a kilogram of carbon dioxide in the air, you've gotta pull a kilogram back out, okay? And that seems to be, to me, a little more rational than attacks because it directly addresses the CO2 problem. - [Audience] So I presume that there is intellectual property behind all this? - Yeah, yeah, I would say so. - [Moderator] Back there, student.

- [Student] Thank you so much for the lovely talk. If I understood your talk correctly, there's a slide where you say that the total land area needed for this is about 2 billion acres, isn't that right? - I'd have to refer back to the chart, but the acres dependable, whether the quality of land. So if you have lower quality land, you need a little bit more, but there's a lot of low quality land around and so forth. - [Student] Well, the 2 billion acres is roughly the land mass of the entire United States. So it's a lot of land, right? - Okay, it's actually, so that's a good question. I get that question quite frequently.

Americans think that the world revolves around America. America residents about 6% of the world's land area. So the way to think of it, is that there are other countries in the world that are very large and have their own agriculture. - [Student] Okay, if I just follow up real quickly, wouldn't this require us to all eat much less beef, right? If you wanna reuse the pasture to grow this, then we all have to reduce our beef consumption.

Isn't that correct? - No, not at all. There's plenty of land for beef and so on. So the way we set it up, is that we weren't gonna touch any of the land that was currently being used for agriculture.

And I showed you on the last few slides that there's a lot of agricultural land that has fallen out of production because of the Moore's law for agriculture. And so there's actually, like I go back east to New England, and they just can't compete. Those farmers cannot compete with Midwestern farmers. And a lot of that land has just been reverted to woodlots. So no, there is, that's an absolute necessity. In fact, it's a regulation in Europe, is that whatever you do, you can't disturb land that is used for growing food.

- That one at the end. - [Joey] Hi there, I'm Joey. I'm a member of this school's effective Altruism Club, and I was wondering like the particular, like carbon sequestration being so important to the climate crisis, I feel this would be a very good project to have, like either material or technical support from the effective altruism community, if you've heard about it. - So I'm all in favor of altruism being effective. I know it's not always effective. Some people have good intentions and it doesn't necessarily work out.

But I think from the business viewpoint, we don't think of this as altruism. We think of this as an environmental problem that has to be regulated by the government, like many other environmental problems. - Stick here, here. That black boy, that I look (indistinct). - [Audience] Nice talk.

Has there been any study on four millimeters of ethylene, the longetivity over 10,000 years? And is there a possibility that there can be a hole in it? And then what is the consequence of it? - Yes, that's a good question. As I understand the question is over let's say 2000 years, it could be that maybe some tree roots would get down there and cause a hole and so forth. And so one of the things we do is we cover the environmental chamber, we cover it over with dirt. We budgeted 20 meters deep, so that's 65 feet deep. And we think that's actually safe. But one of the things I asked my co-author to figure out is let's say we would add more depth to protect it from some, maybe some animal or something digging down.

And it costs only 40 cents a ton for every meter of depth. So at a certain depth, you're pretty much safe from disturbances, both from plants and animals. But it's certainly something to be concerned about.

Thank you. - Okay, I'll take one more. I have a question. A couple of times you said that the farmers would be thrilled to have this cash crop. - Yeah.

- But all the numbers you gave, I think, and that's my question, were based on the cost. So what's the margin for the farmers? - That's a good point. The farmers have to do better than break even. And in some cases, they own the land, and they can make a profit.

And in other cases they have to rent the land, and they have to pay the rent and so forth. So this corresponds to the current level of agricultural cost, in the sense that the farmer has to build in his profit in order to make a living. And so I think this is, that's the way we normally cost things. - [Moderator] Okay, so $60 a ton includes that factor? - It includes what it would cost the farmer to rent the land. That's correct.

- Well, but that's then the farmer's still breaking even. So where's, where's the farmer's cash? - I think you can't assume that the farmer is only breaking even 'cause then why would he stay in business? - Exactly. - Okay, so, this is the cost at the point of sale of the farmer. - Oh, I see. - So the example I gave is the farmer gets paid by Chicago Board of Trade. So he has to deliver it to Chicago, okay? And then they will pay a certain amount, and he has to pay for the cost delivery, and he has to build in his profit.

Now the thing about farming that us normal people don't understand, and farmers understand this very well, is that some years they lose money, okay? And this is a problem, okay? And, but they're supposed to make it up in other years. And if they can't, then there's no more farming. - Okay, well I don't see any more questions, so I think we can close the session.

And thank, Eli, for another really creative and thought provoking new idea. (attendees applaud) - [Eli] Thank you.

2023-10-01 00:57

Show Video

Other news