The Transport Hierarchy: a new Clean Transport themed report from the Institution of Mechanical Engineers published ahead of COP26

The Institution of Mechanical Engineers has published a new report taking a focused engineering look at transport system design, addressing how we can change our approach to reduce emissions across all transport modes.

The report “The Transport Hierarchy – a cross-modal strategy to deliver a sustainable transport system” lays out a high-level structure for analysing transport with the goal of making it more sustainable in the future.

Transport is the largest contributor to the UK’s emissions, accounting for around 27%, of which around 90% come from road vehicles.

The Hierarchy highlights three priorities which can be used for coherent planning and engineering of transport systems to cut emissions. The first priority is to reduce demand for transport, followed by modal shift to encourage the choice of transport with the lowest environmental impact.

The third priority is to improve transport vehicle energy efficiency and boost the use of renewable fuels.

The paper develops the theme of modal shift from road and aviation to electrified rail as a key solution to reducing the UK’s greenhouse gas emissions from transport.

Matt Rooney, Head of Policy at the Institution, said:

“The Hierarchy is a powerful tool for thinking about how to make our transport system more sustainable. Demand reduction and modal shift are often low cost, sustainable solutions that are overlooked in favour technological fixes.

Technology will be crucial to reducing transport emissions, but policymakers should look for low hanging fruit first.”

Amol Gulve, co-author and IMechE COP26 Clean Transport Lead, said:

“Empowering new technologies and renewable fuels are key contributors to achieve sustainable transport solutions that will not only meet net-zero emission targets but will also provide significant social benefits.”

Dr Ken Hart, co-author and Visiting Fellow in Aerospace Engineering at the University of Hertfordshire, said:

“The urgent need to provide environmentally clean transportation of all types presents a number of very substantial and complex technological challenges. The engineering approach to this is to identify the barriers, deal with them as a number of more manageable problems – and then provide the solutions.”

This Hierarchy has similarities with the Institution’s Energy Hierarchy (reduce demand, increase efficiency, use renewable and sustainable energy sources, use other low carbon sources, use conventional energy).

The Institution’s goal is for the Hierarchy inform transport policies of all government departments and businesses when making decisions on their transport choices in terms of both use and planning activities.

The release of the report has been timed to coincide with the IMechE’s two-day pre-COP26 conference, where the afternoon of Friday 29^th October has been devoted to the COP26 Presidency Theme of Clean Transport.