Welcome to Sentivia

Okay, let me tell you a bit about myself and what I'm doing here. I'm someone deeply engaged in the world of climate solutions, specifically focused on the very tricky challenge of removing carbon dioxide directly from the air. You might say I'm an engineer, a scientist, a researcher - but more than that, I'm deeply concerned about the future of our planet, and I'm committed to finding real, actionable solutions.

It's really important to me that people understand the scale of the problem, which is why I started by explaining the current CO2 concentration – about 400 parts per million. Think about that. For every million molecules of air, just 400 are CO2. That's like trying to find one person in a green shirt in this whole room of people. It's a really small amount, a very dilute presence, and that's exactly what makes capturing it directly from the air so difficult.

I'm not going to lie; while pulling CO2 from the air is challenging, we have to face the reality that we aren't doing enough to prevent emissions from going up. So now, we have to look back at methods of pulling CO2 back out of the air. So while it’s hard, it’s actually quite possible.

Now, the Earth has natural processes in place, like oceans, soil, plants and even rocks, that removes CO2 from the atmosphere, but even accelerating these won’t be enough. That's where my work, and the work of so many others, comes in. We're developing technologies that mimic those natural processes, creating what I like to call a “synthetic forest.” It is essentially a man-made system to extract CO2 from the air.

There are two main approaches. The first is using liquid-based chemicals that grab CO2. It involves packing a large space with material and then filling that space with liquid and using fans to bubble the air through the liquid and the CO2 is separated and binds to the molecules in solution. The other is using solid materials, with similar functionality, but no liquid. Both approaches require a lot of surface area for optimal contact with the air since we're grabbing those small amounts of CO2 from the air.

These air contactors have to be very large and wide, but they need to be relatively thin. If they are too deep, it requires an incredible amount of energy to bubble all the air through the material. So that is a key optimization in the design. And once you’ve captured the CO2, you have to be able to recycle that material that you used to capture it, over and over again to make this process sustainable.

The real energy hog, and something I spend a lot of time working on, is the recycling process. To release the captured CO2, you need an enormous amount of heat, because those grabbing chemicals bond so tightly to the carbon dioxide. However, with that heat, you convert the dilute CO2 that you initially capture to high-purity CO2, which is essential for liquifying, transport, and use in a variety of ways. It can be used as a fuel, a chemical, or something to store and bury.

But here’s the kicker: just to remove one million tons of CO2 in a year requires about as much energy as a power plant, around 300 to 500 megawatts, which is absolutely critical to understand for us to make the process both sustainable and affordable. And of course, if you use a coal power plant, you might as well not bother, because the process would cause more CO2 to be emitted than to be captured.

The cost can be incredibly expensive for this process if it is energy-intensive. Some estimates say it could cost as much as $1,000 per ton to capture CO2, which is obviously not economically feasible. We need to bring that cost down, which is what I, along with many others, are currently working on. Some companies today are getting that number to $600 per ton, and there are other technologies being developed that can do it cheaper than that. I want to mention a couple of these companies.

There’s Carbon Engineering in Canada who uses a liquid-based capture approach. They co-capture both the CO2 from the air and also from burning natural gas for the heat required. This offsets excess pollution and reduces costs. Climeworks in Switzerland and Global Thermostat in the US use solid materials. Climeworks uses geothermal heat or excess steam from other industrial processes to keep costs down. Global Thermostat is optimizing the heat required and the speed it moves through the material for more efficient CO2 capture.

Here's another advantage of synthetic forests. They can be much smaller than real forests, such as the Amazon rainforest. The Amazon is a marvel, capturing 1.6 billion tons of CO2 each year, but a manufactured direct air capture plant could capture the same amount in 500 times less land. We also don’t have to place these plants on agricultural land, which prevents competition between food production and carbon capture, and we don’t have to cut down existing forests to do this.

Ultimately, I believe that negative emissions, which is removing carbon and storing it permanently underground, is where we need to be. But right now, there isn’t really a market for that, so a lot of companies are focusing on making things with that captured CO2 like fuels, plastics, and even gravel. While these markets are useful, they won't solve our climate crisis.

What will solve our climate crisis is investing in the technology and building capture plants so we can learn and bring costs down. This also requires regulation, subsidies, and taxes on carbon. It has to be affordable for the majority of society, not just the few who are willing to pay extra.

And we need to invest more in research and development. If we invested like we did during the Apollo program, about a half percent of our GDP, we could spend $100 billion. If we invest only 20 percent of that, or 20 billion, and get the cost of capturing down to $100 per ton, we could build 200 synthetic forests that each remove a million tons of CO2 each year, which, in turn, could reduce about 5 percent of our annual emissions in the US. This is huge, because five percent is what long haul trucking and commercial aircrafts contribute.

Now, if we use natural gas to power these plants, it would be about half the size of Vancouver. But if we use clean energy, like wind or solar, it will be about the size of New Jersey. So finding the resources to power these plants with clean energy is also something I need to think about in my work.

I want to end by emphasizing that these technologies aren't a silver bullet, but a necessary component of a comprehensive climate strategy. We need a combination of everything – improved energy efficiency, reducing emissions, improved farming, and direct air capture – if we hope to achieve net-zero emissions one day.

I think about this like my husband, who is an emergency physician. He saves lives in a moment, and I want to be able to do that on a larger scale. So even though a synthetic forest won’t be as pretty as a real one, if we take the proper steps, we can preserve it and all the people we love and cherish and our future generations. I have devoted my life to this, and I know this can be done. Thank you.