Seratech interview in Undaunted close-up series

Working with the foundations of net zero cement

Franca Davenport

6/22/20234 min read

By refocusing on the underpinning processes of concrete manufacture, Seratech has created a net zero cement without changing its fundamental ingredient. Undaunted reporter, Franca Davenport, explores this clever chemical approach with CEO and Co-Founder, Sam Draper, for Undaunted’s Climate Solutions Up-Close series.

Cement is one of the largest resources consumed by humans, second only to water. It is also responsible for 8 per cent of our global CO2 emissions.

Being the main ingredient in concrete, cement is everywhere. And with its ubiquity comes a deep familiarity within the building sector, making it a challenging material to target for change.

Rather than looking to disrupt the industry and replace cement, Seratech has taken a novel approach to reducing its climate impact, maintaining the familiarity of this well-known building material while reducing its emissions to net zero.

“Everybody likes concrete. It’s a known quantity and although there are some very smart ideas to replace it, construction doesn’t have the capacity to try new materials or to insure them as part of buildings. We wanted to offer a solution that kept cement simple and familiar.”

Sam Draper, Co-Founder & CEO, Seratech

Getting cement to net zero and beyond

Traditionally the building sector substitutes up to 40 per cent of Portland cement with a waste material, such as fly ash or slag, which lowers its environmental impact to an extent. By focussing on this ‘supplementary cementitious material (SCM)’ Seratech identified an opportunity to reduce emissions further. They developed a process that takes the CO2 produced by cement manufacture to make silica, and then uses the silica to substitute the Portland cement. As the process has used CO2 to create the silica, the resulting cement becomes carbon neutral.

Seratech’s technology uses a common mineral called olivine which absorbs CO2 when it weathers naturally. By extracting the gases directly from the flues in a cement factory and adding them to olivine the technology accelerates the process and produces carbon negative silica that can be mixed with cement.

It also produces magnesium carbonate that can be used to make a range of zero carbon construction materials and consumer products, enabling Seratech to unlock the potential for the future cement industry to go one step further and become net negative.

“We call it enhanced, enhanced weathering,” says Co-Founder and CEO Sam Draper. “Although olivine has been identified as a prime candidate for carbon sequestration for years, many technologies rely on energy intensive high temperatures and pressures to carbonate it. We use a slightly different approach which minimises energy consumption and also ensures that the silica and magnesium carbonate come out of the process separately so can be used in subsequent construction products.”

From concept to company

The company is an entrepreneurial child of the pandemic, founded in 2020 by Barney Shanks and Sam Draper who were both PhD students at Imperial College London. The two of them began working on the concept as a lockdown project and when they strength-tested the material for an academic paper they became aware of its potential in the real-world. “The numbers just worked,” says Draper. “For the cement to become carbon neutral we had to use 35 per cent of the silica that we produced and this is also the upper limit used in the industry to supplement Portland cement.”

In early 2021 the two of them got in touch with the Imperial Enterprise team to start the IP process and, six months later, they joined The Greenhouse accelerator. “It was fantastic to be in an ecosystem with other start-ups that share common goals,” says Draper. “And provide such a range of perspectives and experiences.”

Since their time on The Greenhouse, Seratech has received grant funding from the Engineering and Physical Science Research Council, the Higher Education Innovation Fund, and the DT Prime fund from the Institute for Deep Tech Entrepreneurship at Imperial.

With this funding Seratech has grown the team and scaled up lab production from grams to kilograms, allowing them to showcase their technology in the form of a 100-block wall at the 2022 London Design Festival. “Having that physical sample has been massively instrumental in attracting interest,” says Draper. In October 2022 they won the international Obel award for outstanding architectural contributions to human development.

Looking to the future

Seratech is now looking to partner with property developers, architects, structural engineers and building contractors so they can evaluate the material for functionality, safety and durability.

Ultimately, they want to explore ways to licence the technology to cement manufacturers to use directly in their kilns. “We believe this will be the quickest way to scale and achieve global impact,” says Draper, who estimates that if their cement reaches its full potential and is implemented at a global scale it could mitigate 2 to 3 billion tonnes of CO2 per year. “One way to accelerate this is by changing environmental policy and taxation on emissions,” adds Draper. “And the key to this is showing there are solutions, which are not only effective, but also economically viable.” Indeed if scalability of Seratech’s cement can be achieved then the ‘everywhere-ness’ of concrete no longer represents a challenge but more an opportunity to decarbonise the construction sector. As emissions from concrete are expected to double over the next 10 to 15 years, this opportunity could be even larger in the future.

Climate Solutions Up-Close

Take a deeper-dive into innovative climate technology by exploring other posts in Undaunted’s Climate Solutions Up-Close blog series.