ASU KEDtalk: Carbon is a terrible thing to waste

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Like throwing trash into the street, each year we pump tons of carbon dioxide into the atmosphere. Klaus Lackner has developed technology poised to collect and reuse our carbon while cleaning the air.

Nov. 15, 2017

Popular Science magazine named the carbon capture technology developed by Lackner and his colleagues, and commercialized by Silicon Kingdom Holdings, as a top technology of 2019.

Want to learn more? See our Q&A with Lackner and take a peek inside his lab to learn how his technology works.

Video transcript

Hello, everybody. Thanks so much for having me here. I'm delighted to talk with you about a topic I have been working on for the last 20 years-- actually more than 20 years-- and this is about how to manage carbon, and really this is about climate change and having energy at the same time. We need to figure out how to balance our carbon books.  

So, for this theoretical physicist here, it seems, actually, very simple. It's a conservation law. If you take carbon out of the ground and you put it into the system, it will stay there unless you take it back out. From a societal perspective, this is much, much more complicated because, as we fix it there will be winners and losers. On the other hand, we also need to have an engineering response to it we don't have, yet, fully developed.  

So, our question, then, is how to do that, and I started on the engineering side. So, I started to work on the idea, how can we pull the CO2 back out of the atmosphere? Over those two decades, we all talked a lot about climate change and how serious an issue it is, but we ended talking. There was very, very little action, and I think, in part, that is because we thought of the problem as we have to reduce energy consumption, we have to stop doing what we are doing, and we should really think about it as a waste management paradigm, which actually, I think, will help us to make it an easier problem.  

Think what my neighbors would say to me if I simply got out and dumped my garbage in the street and left it there. They would probably call the cops on me and they wouldn't take it for an answer if I came back to them and said, see, I really thought about this problem. I worked very hard on it and over the last two years, I managed to reduce my emissions, my garbage, by 20%. Aren't you proud of me?  

But if you think about it for a moment, this is exactly how we think about the problem in terms of climate change. We pat ourselves on the back by having a 10% reduction, which by the way we never had. So, we have to clean up after ourselves, right? And we have to figure out how to do this. The other neat thing about having a waste management paradigm is that you actually don't have to think of it as something you can't have.  

Sewage is unavoidable. We know that and therefore we deal with it, rather than saying we can't have any, right? And so, we are working on this on water. We all understand we need water. We all need food and we want a clean environment, too.  

For energy, we actually have to also come to the point to admit that we need it, right? It gives us clean water. It gives us food. It gives us raw materials and, by the way, if we want to clean up after ourselves, we also need energy. So maybe we can solve the problem by simply avoiding fossil fuels completely. Well, perhaps. Perhaps over time, but not in the time we have. So, we are not running out of fossil carbon and climate change is not self-limiting, and there always will be an excuse.  

So, we have to figure out how to do this differently and think the answer is we have to demand that we cannot wait. We have to demand cleanup and then the neat thing of having many different options is the markets can figure out which of these options are the most cost effective and which ones we follow.  

So how much time do we have left? Is it a few years? Are we already too late? I think the best analogy to have there is to think about it like a carbon credit card the world is charging to, and the problem is like the old American Express. We don't really know what the overdraft limit is. We don't quite know where we are, but we do know the account balance because when we started in the pre-industrial times, the CO2 in the atmosphere was stable at 280 parts per million and we started to get worried about it in Rio in 1992.  

We were at 356 parts per million in the atmosphere and, by the way, we had a spending habit of 1.3 parts per million per year. Right now, we are at 404 parts per million and our spending habit has gone up to 2.5 parts per million a year. So we are higher than we ever were and we are racing up in the amount of overdraft faster than we ever had.  

Now, it's not clear where exactly the limit is. If you talk to the IPCC, the Intergovernmental Panel on Climate Change, they feel it's around two degrees warming, which is equivalent to 450 PPM or so. We are about 16 years away from that.  

So, we are nearly there. And some people, like people who subscribe to, think we're already in overdraft and we just haven't quite figured out how much this will hurt, because it takes another 100 years to really hurt. So here we need to do something. Here at ASU’s Center for Negative Carbon Emissions, which I started a couple of years ago when I came here, we are taking this seriously and we are working on technologies to pull carbon dioxide back from the atmosphere.  

Technically, that's not all that difficult. If you think about it, every tree can do it. And by the way, there are machines in every submarine and every spacecraft that do the same thing. So we know how to do it. The trick is to make it affordable. So we designed artificial trees, which literally stand in the wind, their leaves, which are made out of a plastic, sort of have the breeze blow over them, and they bind to the CO2. And they do this about 1,000 times faster than a natural tree could do.  

This plastic binds CO2 when it's dry. So out in the wind, it picks up CO2 after it dries. And then it releases it when it's wet. So the process is actually very simple. Think of this like leaves or a filter where the air blows through for about 45 minutes to an hour, then it's loaded up. Then you pack those filters in a box, make it wet inside the box, harvest the CO2, which comes off, process it further on, and once the wet leaves are finished and have given up their CO2, you simply put them back outside. And in the wind, they dry again, and the cycle repeats itself over and over.  

So what do we do with the CO2 once we have it? Well, first of all, we can store it, right? And we are working on mineral sequestration, and we are now using minerals you find here in Arizona to bind up that CO2. We can also make that CO2 back into fuel. We are, again, working on a project where we are taking the CO2, feeding it to algae, which make biofuels out of it. We could also chemically take water and CO2, rip the oxygen out with electrolysis or some other process, and then bind it with processes, which have been around for a 100 years, back into a fuel, or alternatively, into plastics, which you could store. So if you look at the infrastructure we have, it could hide a lot of carbon.  

So in a way, our air capture becomes on the one side the street sweeper, which cleans up the CO2 litter, and on the other side it becomes the carbon miner, which pulls resources back out of the atmosphere for new materials. And of course, making product is much more satisfying than just dumping it into a disposal site. But on the other hand, we are all responsible for between 15 and 20 tons of CO2 a year. We don't consume that much. So we will have to be honest about it in the end. In order to balance the budget, we will have to put some of the CO2 away in disposal.

So carbon taken from the ground must be put back. Some people are doubtful that this can be done. They are skeptics and they say you can never agree to get low enough in costs, and you can never reach the scale you need to get to. So let's ask the question, how big would we have to be?  

If you want a ton a day of carbon dioxide back, you will have to build a device, which is roughly as big as a trailer truck or a standard size shipping container you can see in a harbor. If you wanted to get all the CO2 back we produce right now by this means, you would need 100 million of them. That sounds like a horribly large number, but on the other hand, there are a billion automobiles on the planet. And we build about 80 million of them a year. So we have the industrial capacity to get there if we choose to do that. So industrial production can make that happen.  

So we know we can reach the scale. The second question is, can we get to an affordable cost? And the first question there is, what is actually affordable? We are working at it. There are a few startup companies who want to sell you CO2 they captured from the air, and we all think we are around $100 a ton of CO2. Some actually think they could get a little lower with the technology they already have. I feel we can get a lot lower if we actually advance the technology we have.  
If you look at how much raw materials we need, in the box itself, in the energy we consume, and the water, its less than $15 per ton. Now is that a big number or not? If you think about $100 a ton, that's 85 cents extra on a gallon of gasoline. If we can get it down to $30 a ton, you would have to pay one quarter per gallon more at the pump in order to be carbon neutral. So think about that.  

So the question then is, can volunteers lead the way to make it happen? Because we seem to have failed by regulatory ways of doing it. Imagine you could push a button at the pump where you say I want my carbon back, and you pay an extra $0.30 or maybe $0.50 extra, and that carbon will be taken back on your behalf. If volunteers started to do that, you, first of all, start having a market. Once you have a market, it will get cheaper. And so you can then make it happen.  

So the question then becomes, how do we convince people that this actually needs to be done? And that's difficult and will take time. But on the other hand, it exactly mirrors the discussion we had all in the 19th century about sewage. And eventually, people got convinced that sewage is dangerous, causes a problem with cholera and typhoid. And once people understood that, they were willing to pay the money. Unfortunately, CO2 doesn't smell, so it's harder to deal with.  

On the other hand, every gallon of gasoline you put out puts 20 pounds of CO2 into the atmosphere. Think about this next time you drive a car, right? And it will be there for thousands of years.  

So how do we get there if we start small? We have to build that first one ton a day unit. Maybe a few of them. That's a $20 million project, then you will have them. Then you can start mass producing them. I would argue we scale up just like the car engines in numbers, not in sheer size of individual units.  

Then that could actually go quite fast. If you look at a picture from New York in 1900, you are hard pressed to find a car. If you look at 1925, they're everywhere. Jet planes got in between 1951, when the first one started to fly, and by 1965, the world's fleets were jet planes. So it takes a decade or two for a new technology to really get in. Think of the cell phone. You see the same kind of thing.  

So what we really need is that you and I and everybody else have to demand to close the carbon cycle, which is a little bit like the recycling projects of the 1970's and 80's. You can convince people ultimately to do that. And if we do that, the policies will follow the volunteers. In the beginning, recycling was entirely voluntary. Today, I don't have all that much of a choice anymore because people accepted it. And it is a good thing. All right?  

So volunteers will never change the carbon balance substantively because they will never be enough. But they will give the politicians, ultimately, the cover to make it happen. So what we need is a well-designed buy back the carbon campaign, which sort of mirrors the old recycling campaigns, and in a way then, gives the politicians they cover they will need.  

The last 25 years, in my view, have shown that waiting for others to first make this happen will never work. Top down approaches seem to fail miserably. So let's begin at home. Ask for ways to buy the carbon back. Demand that button on the pump. And then over time, things will come into balance. And I think that's what we will need. Thanks so much for your time.


Klaus Lackner is the founding director of the Center for Negative Carbon Emissions. CNCE is partially supported by Arizona’s Technology and Research Initiative Fund. TRIF investment has enabled thousands of scientific discoveries, over 800 patents, 280 new startup companies and hands-on training for approximately 33,000 students across Arizona’s universities. Publicly supported through voter approval, TRIF is an essential resource for growing Arizona’s economy and providing opportunities for Arizona residents to work, learn and thrive.

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