Reducing embodied carbon in transport infrastructure will help drive the sector’s contribution to achieving net-zero, says Kim Yates.
Embodied carbon in concrete, asphalt, steel and the other raw materials used to build roads, tunnels, rail lines, and airport terminals and runways adds considerably to the transport sector’s overall carbon footprint.
Initial plans for the Lower Thames Crossing (LTC), a planned tunnel between Essex and Kent in the UK, would have produced about 1.8Mt of CO2e in the construction process, with embodied carbon making up between 70% and 80%. Carbon emissions from building phase 1 of HS2, the high-speed rail line between Birmingham and London, including tunnels through the Chilterns, have been estimated at 6Mt.
There are ambitions to significantly reduce embodied carbon. National Highways is due to submit a revised Development Consent Order for LTC which will include bold measures to cut embodied carbon on the project. Meanwhile, the company developing HS2 has adopted a stretch target to reduce embodied carbon emissions in main works civil contracts by 50%.