Solving for Zero is a climate change documentary that is about solutions, not just pointing a pending apocalypse. Right away, that makes it different and welcome. It explores the race for technological advances that will help us reach net zero carbon emissions by 2050. Leading up to Earth Day 2022, it introduces audiences to the scientists, start-ups, and solutions at the environmental forefront of this mission in a new original documentary, produced by Wondrium and Blue Chalk Media, based on Bill Gates’ best-selling book, How to Avoid a Climate Disaster.

Solving for Zero premiered on Wondrium on April 8, 2022 followed by the 10-part educational series, Solving for Zero: The Search for Climate Innovation, on April 15, 2022. To stream the film and series, go to https://www.wondrium.com/.

Grace Andrews, one of the scientists featured in the film, discussed coastal carbon capture, one of the most promising strategies being developed to combat excess CO2. She discussed the new technology, her company Project Vesta, and the documentary.

What is carbon capture in general? And how does it address like current problems in the environment?

Right now, we are in the middle of what some people – myself included – call a climate crisis in that, you know, we have been emitting fossil fuel into the atmosphere. Gases like carbon dioxide are driving global temperature. This is causing problems around the world. Predictions are that it will continue to cause fairly catastrophic impacts in the coming century. 

For people working in the climate change mitigation space, there’s really two ways that we think about trying to fix this problem. You can reduce emissions to the atmosphere, which is definitely step number one. It is something that we have to do and we have to do prudently and at large scale. 

The other thing that you can do is actually remove carbon dioxide from the atmosphere, essentially taking CO2 that we’ve already emitted out. That is, what carbon capture is. It is the kind of technology that my company works on, developing strategies to actually take CO2 out of the atmosphere as a second pathway to combating climate change.

What are some examples of carbon capture technologies that are currently in use? And how effective are they?

One of the most popular and widespread strategies for carbon capture at the moment is reforestation. Trees are a great way to take CO2 out of the atmosphere and improve other aspects of planet Earth. Generally speaking, we have a problem cutting down too many trees so reforestation projects are probably number one. 

Beyond that, there are other strategies that people are taking such as trying to enhance organic carbon storage in soils. Carbon capture in the ocean pathways include increasing the growth of seagrass and other organic carbon pathways. 

There are strategies that focus on what’s called carbon mineralization. That involves taking carbon and storing it in the form of rocks, limestone, things like that. You could potentially use that for building material and there are lots of interesting pathways there. 

What I work on and what Project Vesta works on is a form of carbon capture which is sort of an umbrella term for it. It’s called ocean alkalinity enhancement, and it’s trying to store carbon from the atmosphere in the ocean, in the form of something that is called alkalinity.

Now, are all the processes currently in use? Are all of them sustainable? Are there some ways that or are there some sort of industrial versions that are slightly less sustainable?

None of them right now are currently at any kind of significant, really global impact scale. They’re all fairly nascent, I would say, and they all do have their limitations. Reforestation is god but obviously, you need significant tracts of land in which you can grow forests, which are a challenge as we develop land and adopt other uses for it. 

There are challenges in all these spaces. But right now, certain technologies are looking more and more favorable for being able to reach large scale impact in the future. One of the things that’s great about the technology that I currently work on, again, it’s called coastal enhanced weathering, in scientific literature. At Project Vesta our brand of it is called coastal carbon capture. On thing that is good about it is that there is real potential for scale because we’re using the ocean as our storage of store. 

There’s a lot of space for carbon storage there. This is what I think makes it really attractive is that although it’s currently in the development phase right now, the projections are that it could, could certainly have carbon capture potential on the scale of billions of tons of CO2.

You mention coastal carbon capture. What exactly is that?

Coastal carbon capture is a carbon capture strategy that involves working with a natural mineral called olivine, a common mineral. We are milling it into sand and spreading it in coastal environments. When the sand comes into contact with carbon dioxide and seawater, it drives a really slow reaction that ultimately generates alkalinity. CO2 that was originally used in reaction transitions into the form of dissolved carbon called alkalinity, which is conveniently also the antidote to ocean acidification. It’s a natural chemical reaction. 

Again, this is a natural mineral that is found all over the world. The reaction happens all the time. What we’re doing is by grinding it into small sand grains and strategically placing it in oceans, we’re trying to accelerate a natural process so that it captures carbon on significant scales.

Where did the idea come from? Where you just maybe swimming on a beach one day and thought, “This could be a good idea?

The idea has been around for decades. Geologists like myself have been studying the natural process for carbon capture since the 1800s in the academic literature. This understanding of this chemical reaction that happens with olivine is incredibly well documented and well understood. That’s really the origin of this idea has been around for ages. 

It was really in the early 2000s that people started thinking about can we use this natural reaction? Can we speed it up to be advantageous for climate change mitigation? Mitigation has been in the literature for 20 years or so at this point. 

It’s only recently that organizations like mine, like Project Vesta, have really started to investigate it in earnest and think about how do we take this from the laboratory into the real world and actually create a scalable strategy here?

Why is it taking so long for someone to move on? Is there something was there something that they thought might hold it back?

There wasn’t really an urgency around emission technology development until relatively recently. Until recently, it’s hard to even get funded in the academic space. All of the companies that are working on these kind of technologies have only started in the last few years. There wasn’t public demand for it. There wasn’t funding. There wasn’t governmental support behind it. Those are really the main reasons, to be honest.

So now there is support for it.

Increasingly, things have started to look better with the new administration. President Biden has certainly made climate change, a directive amongst all federal agencies. There is now funding coming into this and you’re seeing people increasingly talking about it and interested in helping to progress. We’re getting there and projections are very encouraging.

How much carbon can even take out of here? Is a quantifiable?

Absolutely. The amount of CO2 you can draw out is proportional to the amount of the olivine that you put in the ocean. For about 100 tons of olivine captures 80 tons of carbon dioxide from the atmosphere. You just have to do the math.

If you want to get billions of tons of C2 removed, you need to put billions of tons of sand into the ocean. But that is certainly doable. There are billions of tons of sands, billions of tons of all the available in natural supplies that can be accessed. There’s certainly enough coastal ocean to place that sand.

So how do we know whether the process is working? There’s a there’s a few shots in the movie where you guys are in the water and you have the tubes?

There’s some really nice shots in the movie about looking at us actually collecting samples of the water. What we’re doing and what we’re measuring actually is quantified carbon capture. Like I said that the reaction that runs using olivine sand with carbon dioxide and water generates a form of dissolved carbon called alkalinity. What you’re seeing in the film and what we’re measuring is alkalinity generation that you can go out and you can collect a sample of seawater and measure that alkalinity by comparing that to a baseline.

You can determine what that increase in alkalinity is due to the olivine sand addition itself. So in falling for zero, what you’re seeing there is at our pilot site in the Dominican Republic. Right now we’re working on our baseline. So we haven’t added all the sand there yet, but we are monitoring alkalinity levels and all the other geochemical parameters for about a year to creating this really robust baseline of alkalinity and these other parameters across seasons. So that when we do at all we have a very clear understanding of the relative change due to that output.

When the olivine reacts with the CO2, what’s the carbon product that comes out on the other side?

The carbon product is totally dissolved carbon. You’re taking carbon that was both a gas in the atmosphere and you’re changing its face so that now it’s dissolved in seawater. And that dissolved carbon is called bicarbonate. But another way of describing that like I said, is alkalinity.

Are there any other byproducts in that reaction?

Everything that was originally in the olivine ends up in the salt phase. So basically all of the made up of magnesium and silica and when you dissolve it, you release that magnesium and silica to seawater as well. Thankfully, seawater already has incredibly high levels of magnesium. And so the small addition that you get from olivine is probably not going to be detectable at all. It’s not something that will change the marine environment.

Even with billions of tons of it.

Even billions of tons of it. So to put this in perspective, if you put billion tons of olivine into the ocean that would only cover .2% of the continental shelf, not even the whole ocean, just the continental shelf. The ocean is really, really big, and it’s kind of amazing. A billion tons of sand is pretty insignificant in those sorts of scales.

This question ties into that one. Are there any possible unwanted effects on the ecosystem because they’re pretty fragile?

Right now, we’re in the pilot phase and so we haven’t put all the sand down yet, but we’re getting ready to do that. It means the initial pilot phase is really of the utmost importance. We’ll be carefully monitoring every aspect of the marine environment, looking at the chemistry of seawater, looking at the composition of marine sediments, looking at any changes in species, marine species abundance and diversity as really everything under the sun. Now, we’re not we’re not expecting to have significant changes here. 

Of course, we have to actually demonstrate that in the real world. And I’ll say that’s part of why we think that this is going to be safe because we’ve been spending the past few years doing extensive amounts of laboratory testing and collecting the data before we actually move out into the field. 

That said, I mean, there are certainly some aspects of this that are unavoidable. For example, when you place any kind of sand into the coastal environment, you are covering up the sand that’s underneath it. There are marine organisms, benthic organisms that live in that sand, and so you’re, you’re coating that habitat. 

This is something that can have a smothering effect on marine organisms, and that is certainly largely unavoidable. One way that we are mitigating against that is by working within the coastal protection industry. 

Does the ground up version, the sandy version of olivine react in the same way as when you find it naturally in like rock form?

Absolutely. The only difference is that when you grind the olivine from a chunk of rock into a sand, you are basically increasing what we call the reactive surface area of that rock. So you’re increasing the area that’s available to interact with seawater and CO2. So the reaction is completely the same if you have a chunk of rock versus sand. The only difference is because you have increased your reactive surface area, you can see that the same volume of sand can react much quicker. That is a key strategy in terms of speeding up this natural process to capture carbon on human timescales.

Now is it is there a possibility of making the water two ways

That’s a good question. The issue with climate changes that we’ve driven, really significant increases in seawater pH. In order to undo all of the ocean acidification associated with fossil fuel addition to the atmosphere is a real undoing 100 years, really, of human history. So that’s not really something we worry about.

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