Modal Shift plus other benefits of trams – Briefing note: Making a case for Light Rail vs bus transport solutions – From Coventry project



Cities need to ensure efficient mobility of its citizens. Whilst historically this has been achieved via a mix of personal car use and bus networks, these modes are coming under pressure due to increasingly stringent emissions targets. On one hand, CO2 output is linked to climate change and on another, particulates and NOx are linked to decrease in public health. Whilst proposed low emission zones in cities may push internal combustion engine vehicles out of cities, alternative solutions for group transportation are now required. A number of solutions are in trial or already in service. For example, several cities now have electric-only bus routes utilising new generation single deck battery powered bus vehicles. Alternatively, a number of cities have adopted Light Rail as a ‘backbone’ transport solution linked with other solutions including local busses.

It is worth noting that bus transport can be broadly split into two categories. Firstly, most cities have an organised network of busses running with existing traffic. Secondly, it is possible to invest in a dedicated network of bus routes, generally known as a ‘quality bus network’ or Bus Rapid Transit (BRT). BRT solutions require significant infrastructure investment similar to Light Rail Transit (LRT).

This note briefly identifies the case for LRT over BRT as a solution to a city’s public transportation needs, but it should be noted that a new report has been released today (15th October 2021) strengthening the case for Light Rail Support:

Public perception

  • Busses are not generally well-received by the general public whereas LRT is. A recent (pre-covid) DfT report [Bus Statistic – June 2018] highlighted that despite population growth and congestion in cities, bus usage in the last decade (2008-2018) has declined by 11.8% outside of London[1]. Conversely, LRT usage has grown by 41.5% since 2008.


  • A number of scientific studies have highlighted a public preference for LRT over bus transportation although the reasons are not entirely clear[2] . At least some of this preference arises because LRT provides a reliable service with known travel times. Interestingly the preference is less evident when installation costs are made clear to the public[3]. The affordability of the proposed CVLR service will mean that public will continue to prefer LRT.


  • According to the UK Urban Transport Group[4], LRT provides a fast, frequent, cost effective mode of moving people in and around urban environments. There are nine LRT systems currently in the UK.


  • LRT systems have a high passenger satisfaction rate of 91%[5].


  • LRT systems are successful in driving transport modal shift, with 30% of Nottingham Tram users switching from cars, and 29% of Manchester Metrolink users stating they would use a car if the tram system was not available. Furthermore, across the Manchester Metrolink network, 48% of passengers reported having a car or van available for the journey they were undertaking, with this varying between 39% and 58% depending on which line they were travelling[6].
  • Some LRT passengers state they would use a taxi or car if Metro was not available, for example, up to 42% of passengers on the Tyne and Wear Metro would switch to using a car or taxi if the Metro was unavailable[7].


  • The CVLR LRT scheme will be zero emission at point of use. As the CVLR vehicle is battery-powered, there are no tailpipe emissions.


  • Importantly the CVLR scheme will have no overhead catenary as rapid charging will be applied at the end station of the line. The position of the CVLR vehicle will be defined by the rail track which means that direct (cable) overhead charging can be applied. Current electric bus technology relies on underfloor wireless charging which is slow and inefficient [8].


  • The so-called Oslo-effect identifies that rubber tyre wear and brake dust are a major contributor to poor air quality and are detrimental to health[9] .


  • DEFRA report that 60-70% of non-exhaust emissions arise from tyres/brakes/road wear [10]. The CVLR vehicle will not use rubber tyres and will use regenerative braking most often thus giving near-zero non-exhaust emissions. All busses must use tyres.


  • In September 2021 the WHO released new guidelines to improve air quality, taking into account non-exhaust emissions[11]. They attribute 7m deaths worldwide as a result of poor air quality. The CVLR system will not use rubber tyres and will not therefore produce particulate emissions.


  • The lowest emissions are generally from rail vehicles, which deliver between 4.5 and 36 grams of carbon dioxide equivalent (gCO2e) per passenger kilometre, followed by electric vehicles which have emissions of 39 to 75 gCO2e per kilometre, and coaches and buses, emitting 27 – 118 g CO2e per passenger km[12]


Urban regeneration

  • Light Rail is known to stimulate urban development. In Manchester, the Salford Quays extension cost £150 million, but has led to 3000 permanent jobs, £60 million of investment by businesses, and a boost to the Greater Manchester economy of £70 million per year[13].


  • Light Rail benefits economic activity in urban areas. For example, land values around the Tyne and Wear Metro rose by 17.1% compared to non-served areas[14].


  • An Economic Impact Assessment has been carried out for CVLR which illustrates that the scheme will deliver the following benefits for the city. The moderate and major positive impacts are highlighted in red below[15]:
    • Local Impacts within ‘First Route’ CVLR Corridor (Core route only)
Local Corridor Impact Area Summary of Potential Scale of Impact
People CI-1: Access to skills & employment Moderate positive impact
CI-2: Access to housing Neutral impact
CI-3: Access to services and amenities Minor to moderate positive impact
CI-4: Safety & security Minor positive impact

(social value = £1.2 to 2.1 million NPV, 2020 prices)

CI-5: Active health Major positive impact

(social value = £16 to £31 million NPV, 2020 prices)

CI-6: Personal & community wellbeing Moderate positive impact

(social value = £3.1 to £6.3 million NPV, 2020 prices)

Place CI-7: Existing Housing Major positive impact

(LVU – £27 million to £78 million NPV, 2020 prices)

CI-8: Existing Commercial Property Moderate positive impact

(LVU – £1.5 million and £8.2 million)

CI-9: Future Housing Minor positive impact

(LVU – £0.35 million and £2.3 million)

CI-10: Future Commercial Property Minor positive impact

(LVU – £0.4 million and £2.6 million)

CI-11: Climate & Emissions Moderate positive impact
CI-12: Townscape & Heritage Neutral to minor positive impact
CI-13: Ecology Minor adverse to neutral impact
Economy CI-14: Size of economy Minor positive impact

(indicative £1.0 to £4.25 million NPV,2020)

CI-15: Productivity of economy Minor positive impact
CI-16: Local government finance Neutral impact

NPV = Net Present Value: calculated for 10-year period, unless otherwise stated,                     LVU = Land Value Uplift

[1] Annual bus and LRT statistics: England 2019/20. Department for Transport

[2] David A. Hensher, Chinh Ho, Corinne Mulley, Identifying preferences for public transport investments under a constrained budget, Transportation Research Part A: Policy and Practice, Volume 72, 2015, Pages 27-46,

[3] Bus Transport, First Edition, David Hensher, 2020, ISBM: 9780128201329

[4] Urban Transport Group, Light rail: keeping city regions moving during the pandemic -and building back better afterwards, 19 May 2021.

[5] TfGM, Table 3.1, Metrolink Phase 3: Monitoring and Evaluation Second Report, March 2021.

[6] UK Tram, Freeing Up Our Cities, available at:

[7] Urban Transport Group, What Light Rail can do for City Regions, October 2021


[9] All Party Parliamentary Light Rail Group, The Oslo Effect (The Elephant in the room Killer), March 2017

[10] Non exhaust emissions from road traffic, Air Quality Expert Group, prepared for DEFRA, July 2019.


[12] DfBEIS, Table: Business travel – land, Greenhouse gas reporting: conversion factors 2021, 2 June 2021

[13] Urban Transport Group, Briefing on Light Rail, December 2020.

[14] Peter Newman, Sebastian Davies-Slate, Evan Jones, The Entrepreneur Rail Model: Funding urban rail through majority private investment in urban regeneration, Research in Transportation Economics, Volume 67, 2018, Pages 19-28,

[15] Economic Impact Assessment, Coventry VLR, February 2021