A Martian-Inspired Innovation: Cement Made from Living Microbes
Architect Karen Antorves Paes from Switzerland has pioneered two novel techniques to produce building materials from biocement that hardens at room temperature without the need for high-heat firing. This biocement is created through the action of the soil bacterium Sporosarcina pasteurii, which induces the precipitation of calcium carbonate, resulting in a material with strength comparable to conventional construction mortar. Its applications include non-load-bearing walls and facade panels.
The process relies on Sporosarcina pasteurii breaking down urea to release carbonate ions, which react with calcium chloride to form limestone crystals. Paes describes this as using bacteria to produce a unique mineral adhesive, likening the transformation to baking a cake: "The batter is soft and fragile, but the oven turns it into something solid. In this case, bacteria play the role of the oven."
Cutting-Edge Production Techniques for Biocement
One approach involves creating a bio-ink composed of water, natural gums, sand, and living bacteria for 3D printing. The printed structures are then submerged in a mineralization bath for 2 to 5 days with daily solution refreshment. The second method uses a robotic arm to apply alternating layers of sand, bacteria, and mineralizing agents, building the biocement layer by layer.
In 2025, a biocement structure was showcased at the Venice Architecture Biennale, where it gradually grew over six months in front of visitors. This demonstration highlights the technology’s promise not only for conventional building but also for extraterrestrial construction scenarios, such as future Mars habitats, where transporting Earth-based materials is impractical.
However, Paes cautions that without proper management of chemical byproducts generated during production, biocement construction cannot yet be deemed fully sustainable. Traditional cement manufacturing is responsible for about 8% of global carbon emissions, making biocement a potentially greener alternative if environmental challenges are addressed.
The Swiss-developed biocement technology offers a groundbreaking, eco-friendly alternative to traditional building materials, with significant implications for the construction industry. Its potential use in off-world colonies like Mars could reduce reliance on Earth-supplied resources, marking a critical step in space colonization. Nonetheless, overcoming the hurdles of byproduct disposal remains essential for realizing its full sustainability and requires ongoing research and innovation.
In addition to advancements in biocement technology, global research is also focused on enhancing traditional materials. For instance, scientists from China and Germany have developed new iron alloys that offer greater strength and affordability using recycled scrap metal. This innovation aligns with the growing trend towards sustainable construction practices, highlighting the importance of eco-friendly solutions in the building industry.