Felix Prettejohn

Sustainable decarbonisation of the London Transport System

Decarbonisation of the transport sector is accelerating to meet the challenge posed by climate change with 10.2 million electric vehicles worldwide in 2020, from only 1.2 million vehicles five years ago (IEA, 2021). However, while solving one problem we may be creating another unless we ask, “how sustainable is the decarbonisation transition”?

Current transition strategies can favour technological solutions to reduce the impact of private vehicles and minimise disruption to the status quo. However, their high-cost, environmental impact, and uncertainty in delivering the transition may make this approach mis-guided. Studies have shown that modal shift and demand reduction away from private vehicles is necessary for realistic net-zero pathways, but even these studies can fail to consider the sustainability of their proposed solutions and their suitability to local areas, instead treating the system as homogeneous.

This research aims to identify solutions that can decarbonise London road passenger transport sustainably by addressing the environmental, social, and economic issues local to different areas of London. The spatial variability of these issues and the variation of factors affecting private vehicle use was analysed across London with a novel method used to identify areas of greatest divergence between private vehicle necessity and use. In parallel, decarbonisation solutions were analysed for their effects to a range of sustainability criteria and, subsequently, appropriate solutions matched to local areas according to their needs.

The research found significant variability in the mobility needs and sustainability issues of local areas that must be considered when selecting appropriate solutions to decarbonise road transport. This implies that traditional research methods could improve their selection of appropriate decarbonisation solutions with spatial considerations. Modal shift strategies away from private vehicles were found to achieve multiple sustainability benefits for urban areas as well as large potential for decarbonisation. However, a well-integrated multi-modal system is necessary if it is to challenge the dominance of private vehicles. A method to identify areas of large divergence between private vehicle necessity and use was demonstrated to support selection of appropriate avoid or shift solutions.