Buildings as carbon sinks

October 2024

The construction industry is on the brink of a revolution. In future, buildings could not only be CO2-neutral, but even CO2-negative. The Empa initiative "Mining the Atmosphere" is pursuing precisely this goal. The NEST unit "Beyond Zero" is testing innovative materials that can permanently bind CO2. In this interview, Nathalie Casas (Empa), Corinne Reimann (Implenia) and Christoph Kellenberger (OOS) explain how these technologies can transform the construction industry.

The construction industry is one of the largest CO2 emitters in the world. However, projects such as “Beyond Zero” and the “Mining the Atmosphere” initiative could turn the tide. The aim is not only to reduce the harmful greenhouse gas, but to actively bind it in building materials. These materials, which are being tested in the new NEST unit, could revolutionise concrete and insulation materials and have the potential to make the construction industry climate-neutral or even CO2-negative.

Technology undergoing practical testing
Nathalie Casas from Empa explains that “negative emissions technologies” (NET) are the key to achieving climate targets: “We need to remove excess CO2 from the atmosphere in order to achieve the 1.5-degree target. NETs, which already work in the laboratory and are now being used in the construction industry, will help us achieve this.” Casas emphasises the urgency of taking action as emissions continue to rise.

Sustainability in the construction industry
Corinne Reimann from Implenia sees NET as a great opportunity for the construction industry: “The new materials will finally enable us to make decisive progress in the area of sustainability. The industry has enormous leverage here, but also challenges. Price and acceptance will be crucial.” Reimann emphasises that the functionality and cost-effectiveness of new materials must be ensured in order to enable their widespread use.

The contribution of architects and planners
Christoph Kellenberger, co-founder of OOS, sees the early involvement of architects and planners as a decisive factor: “With our knowledge, we can help develop the right building materials from the outset and integrate them into construction practice. We also need to publicise the potential of CO2-storing materials in the industry and show what effects can be achieved with them.” For Kellenberger, the key to success lies in transparent knowledge transfer and practical solutions.

Political framework conditions and social responsibility
In addition to technological innovation, the construction industry also requires political and economic framework conditions. According to Casas and Kellenberger, clear cost transparency is necessary in order to promote the widespread use of NET. CO2 emissions must be priced fairly and subsidies could help to offset the initial higher costs of the new materials. “The transformation will only succeed if everyone pulls together – politics, business and society,” says Casas.

The “Beyond Zero” project shows that it is possible to turn buildings into carbon sinks. However, this requires not only technological solutions, but also the will of politics, business and society to break new ground. The construction industry has the opportunity to develop from one of the largest CO2 emitters into a pioneer of the climate transition – and the potential to do so already exists today.

More articles