Decarbonizing intraregional freight systems with a focus on modal shift

TLDR

Road freight accounts for about 7 % of global CO₂ emissions, and shifting freight to rail or water could markedly reduce energy use and emissions. The paper outlines five strategies for decarbonizing freight and identifies research gaps for improving modal efficiency and infrastructure to enable modal shift. The authors compare tonne‑km freight by mode across countries, map intraregional corridors, and analyze modal structure and infrastructure needs to estimate decarbonization potential. Road freight dominates with a 60:40 road‑rail split, but rail intermodal transport offers significant potential; however, few countries have policies to promote infrastructure investment and internalize road freight external costs.

Abstract

Road freight transportation accounts for around 7% of total world energy-related carbon dioxide emissions. With the appropriate incentives, energy savings and emissions reductions can be achieved by shifting freight to rail or water modes, both of which are far more efficient than road. We briefly introduce five general strategies for decarbonizing freight transportation, and then focus on the literature and data relevant to estimating the global decarbonization potential through modal shift. We compare freight activity (in tonne-km) by mode for every country where data are available. We also describe major intraregional freight corridors, their modal structure, and their infrastructure needs. We find that the current world road and rail modal split is around 60:40. Most countries are experiencing strong growth in road freight and a shift from rail to road. Rail intermodal transportation holds great potential for replacing carbon-intense and fast-growing road freight, but it is essential to have a targeted design of freight systems, particularly in developing countries. Modal shift can be promoted by policies targeting infrastructure investments and internalizing external costs of road freight, but we find that not many countries have such policies in place. We identify research needs for decarbonizing the freight transportation sector both through improvements in the efficiency of individual modes and through new physical and institutional infrastructure that can support modal shift.