Network Rail has completed the UK’s first low-carbon track renewal, replacing 1,150 yards of plain line track between Honor Oak Park and Forest Hill using a suite of sustainable materials – a milestone that supports its commitment to net zero by 2050.
Led by the Southern Renewals Enterprise, the project combined green steel rail, low-carbon concrete sleepers, recycled ballast, and renewable biofuel-powered trains to cut emissions without compromising performance. The track was fully welded, stressed, and handed back early at line speed, proving that sustainability and operational excellence can go hand in hand.
Key innovations included:
- Green steel rail produced via electric arc furnace, reducing carbon intensity by around 60%.
- Low-carbon concrete sleepers, cutting embodied carbon by 40%.
- Recycled blended ballast, saving up to 13% carbon by reducing virgin aggregate use.
- ISCC-certified renewable biofuel (HVO) for trains.
- Solar-powered welfare units, eliminating diesel generators on-site.
The combined approach achieved a 63% reduction in emissions compared to traditional methods – equivalent to the annual emissions of 200 UK households. Across the first year of the programme, SRE delivered a 10.2% whole-life carbon reduction, setting a benchmark for future renewals.