Geoengineering: Carbon Capture

Direct air capture (DAC) technology has been in the news a lot recently following the announcement of Elon Musk’s one-hundred million dollar carbon sequestration competition, but how does the technology work?

In this episode of Create the Future, we are joined by Nathalie Casas, a chemical engineer and Head of Research and Design at Climeworks, the world leader in carbon dioxide DAC technology.

Climeworks’ innovative modular carbon capture technology is powered by renewable energy and has the smallest land and water requirement of all carbon dioxide removal techniques – including afforestation. Though DAC is no silver bullet to the climate problem, we hear how the air-captured CO2 can be permanently stored underground or recycled into climate-friendly products such as renewable fuels, fertiliser, or the bubbles in your favourite soft drink. Nathalie also shares her experiences working for a start-up, imparts advice to budding engineers, and describes her weekend penchant for sailing on Lake Zurich.

About the guest

Nathalie Casas is a chemical engineer and Head of Research and Design at Climeworks where she and her team develop filter systems that separate CO2 from the air.

During her studies at the Swiss Federal Institute of Technology in Zurich (ETH Zurich), Casas obtained a bachelor’s and master’s degree in Chemical and Bioengineering and completed a PhD in Chemical Engineering.Before working for Climeworks, Nathalie worked at Sulzer, Winterthur, a fluid engineering company specialising in water management technologies.

Episode highlights

• “First we get air into the box and collect the CO₂. Then in the second step we heat it up, CO₂ is released and can then be collected.”
• “I think engineers can contribute quite a lot to the solution of climate change. Everybody needs to be aware of, and everybody needs to work against it or do their share. I think the engineers have the opportunity to deliver technology in order to mitigate it. From this perspective, I think being an engineer, we are in a good position to help.”
  
• “So we have a very modular system. Each cube can capture about 40 to 50 tonnes a year […] so, if you compare it to trees, it's as efficient as 2000 trees per year.”
• “If a new idea is on the table, we set, for example, two weeks to get a bit deeper into it and analyse the risk and upsides or the potential of the idea. Then we decide if we put more time and money on one or the other idea.”
• “From early on, I was very fascinated, on the one hand, by engineering, by math, and on the other hand, by the work you can do in the lab.”
• On studying engineering: “I think you should do something you're passionate about […] If you're passionate about something you are also good at it, or you are really eager to spend time to get really good.”
• “There are two ways you can make use of this captured carbon dioxide. One thing is to store it underground. The other thing is the circular economy, which gets more and more attention […] You capture CO₂, you transform it into fuel, and then you burn the fuel and the CO₂ is released again. By doing this, the CO₂ concentration is not reduced, but you're not adding any CO₂ to the air.”

Photo by Barthy Bonhomme from Pexels