Neustark: “Without technologies that eliminate carbon dioxide permanently, we will not be able to stop global warming”

Johannes Tiefenthaler was, until recently, a laboratory scientist who enjoyed exploring physical and chemical phenomena on a tiny scale. In 2016, while pursuing a PhD in Mechanical and Process Engineering at ETH (Federal Institute of Technology) in Zurich, he realized he wanted to create something with a global impact. “There was a lot of hope. The Paris Agreement had been signed a year earlier, and I wanted to contribute to a better world,” he explains. Three years after that initial inspiration, together with his business partner Valentin Gutknecht, they developed a unique solution on the market to capture carbon from the atmosphere.

They founded Neustark, a name derived from two German words meaning “new” and “strong.” “Both concepts connect with construction and technology,” explains Tiefenthaler. Their technology triggers an accelerated mineralization process, where the injected biogenic CO2 reacts with the minerals within the demolition concrete aggregate, binding the CO2 to the pores and surface of the aggregate. “It’s a very effective way to fight climate change and promote the circular economy by reusing materials.” Neustark has innovated a method for storing carbon in demolished concrete and is now collaborating with companies across Europe that demolish buildings and concrete structures.

QUESTION: Before diving deeper into the project, please briefly describe your background

ANSWER: I studied Mechanical and Process Engineering at ETH Zurich, where I identified carbon capture and storage as being crucial in combating climate change. This was in 2016, shortly after the Paris Agreement was signed. It became evident that, aside from reducing emissions through traditional methods like electrification and renewable energy, solutions were still needed to address unavoidable emissions in sectors such as cement, steel, waste management, and the chemical industry.

Developing technologies that could permanently remove carbon dioxide from the atmosphere was crucial to addressing the emissions we cannot avoid. Without these technologies, we would have no chance of slowing global warming. That was the start of my journey. At that time, I was about 25 years old.

Q: How did the idea of creating Neustark come about?

A: When I was a PhD student at ETH Zurich, I met Valentin Gutknecht, who would become the co-founder of Neustark. He was also in the city, exploring the possibility of storing carbon dioxide in demolished concrete. A mutual friend introduced us. In 2019, we founded the company with a viable business model. Although the process might seem simple, it involved a lot of idea-sharing and numerous meetings. We patented the concept, which is common practice at ETH Zurich —if you develop something, you apply for a patent. However, we knew we were serious about the project when we applied for a grant from the Swiss Federal Office for the Environment to run a pilot model of the technology. This grant enabled us to demonstrate that it was possible to scale up our laboratory achievements to apply to several tons instead of just a few grams.

“Our technology initiates an accelerated mineralization process that permanently fixes the carbon dioxide in the concrete”

Q: How does your technology work?

A: With our solution, biogenic carbon dioxide —naturally produced by living organisms— is captured in biogas plants, where it is liquefied and transported to construction waste recycling facilities. At these facilities, carbon dioxide is injected into concrete granules from demolished buildings and other mineral wastes. Our technology initiates an accelerated mineralization process that permanently fixes the carbon dioxide in the concrete. The resulting carbonated recycled product can be used for road construction or in the production of new recycled building materials. This process enables the captured carbon dioxide to be stored for hundreds of thousands of years, with virtually zero risk of reversion, providing a long-lasting and effective solution for carbon capture and storage. The storage yield can also be converted into certificates —documents that attest to the elimination of greenhouse gas emissions, allowing companies and organizations to purchase carbon credits— which we trade for our customers in the voluntary certificate market.

Q: Why is Neustark’s technology so cutting-edge?

A: We provide technology that allows our partners to eliminate carbon dioxide. Our goal is to eliminate one million tons of carbon dioxide by 2030. This approach is viable today, and I believe we are among the pioneers in scaling this business within an established industry. We currently have 20 plants operating in Europe and more than 50 under construction. While we’re primarily focused on Europe at the moment, we have plans to expand into the North American market soon.

Q: Why is carbon removal essential to address global challenges?

A: When we consider climate targets, we essentially aim to halt global warming, which means we must stop emitting greenhouse gases into the atmosphere. This implies we cannot operate engines that run on oil, gas, or other fossil fuels, and we cannot continue to produce more cement, as it’s an activity that emits significant amounts of carbon dioxide.

There are two main reasons why we need carbon removal. First, we are unlikely to achieve zero emissions; there will always be some residual emissions. We won’t eliminate all diesel engines or stop using fertilizers, so we need to offset these unavoidable emissions by removing them from the atmosphere. Second, we have a limited carbon budget, and exceeding it will lead to a sharp increase in temperatures. The only way to prevent this is by capturing atmospheric carbon dioxide. However, this should be a last resort. Our primary focus should be on reducing emissions first.