Researchers from the Chalmers University of Technology and the University of Gothenburg studied a stretch of Sweedish highway construction and found that the construction industry could cut its carbon emissions by using sustainable technology already at hand.

The researchers evaluated opportunities for reducing emissions in an eight kilometre stretch of the Swedish motorway 44, between Lidköping and Källby, which was built in 2019. Source: Skanska

The construction sector accounts for one-fourth of the world’s carbon dioxide emissions. For this study, the team calculated how carbon emissions could be reduced using existing technology, material choice, production technology, supply chains and transport options.

During the study, the team analyzed an eight km stretch of the Swedish national road 44 between Lidköping and Källby. The construction of this stretch of road was finished in 2019. The materials and activities used in this construction were calculated for their total climate impact and emissions contribution.

The team used the contractor’s climate calculation as their input to break down carbon emissions of materials and activities. They analyzed potential carbon emissions reduction and possible material alternatives.

The contractor was able to reduce emissions by 20% compared to the Swedish Transport Agency’s reference values. But the team demonstrated that emissions could be halved by utilizing today’s technology and they believed that emissions could be completely eliminated by 2045.

This research was part of the project Mistra Carbon Exit, which focuses on transformative solutions to eliminate carbon emissions. Transformative solutions require time and large investments. These solutions would include steel, cement, concrete and asphalt production without carbon emissions and fossil-free or electric vehicles.

While there are sustainable construction solutions are being developed, but the team has found current technologies that can be implemented to reduce carbon emissions. In the study, the team highlights four sustainable technologies: transport optimization, recycling and reuse of excavation masses like asphalt and steel, material efficiency and design optimization and the replacement of cement clinker as a concrete binder. Implementing these technologies would result in large gains for reducing and eliminating carbon gains.

The study was published in Renewable and Sustainable Energy Reviews.