Library image, photo by Alireza Attari on Unsplash

Shared mobility: the case for fewer cars, more sharing

01 December, 2023

Shared mobility: the case for fewer cars, more sharing

Greg Marsden

Clare Downing

Case study   Transport & Mobility

Greg Marsden, Clare Downing and Aimee Eeles

In recent years transport energy use has been rising, so decarbonising the sector is a substantial challenge but necessary if net-zero goals are to be met. Transport uses about 40% of UK energy consumption, mostly from fossil fuels. Ongoing CREDS-wide research is demonstrating that all rapid decarbonisation pathways for the UK require more sharing of fewer private cars.

This has opened up space for a discussion about the size of the UK vehicle fleet, so CREDS’ Commission on Travel Demand (CTD) launched an inquiry in 2019 into ‘shared mobility’ to focus attention on the opportunities to downsize the fleet and make more intensive use of vehicles when they do move. The CTD received 41 submissions from 28 organisations and heard from industry, academia and government in 4 evidence sessions. Its report, Shared Mobility: Where Now? Where Next? was launched in September 2019, and proposed that shared mobility should be a core policy objective for net-zero. The CTD was an opportunity to raise the profile of shared mobility with policymakers.

The Climate Change Committee (CCC) is now recommending shared mobility as a part of a net-zero strategy. The CTD report is cited in the CCC’s The Sixth Carbon Budget Sector Surface Transport Summary Report and shared mobility also featured in recommendations to the Department for Transport (DfT) in CCC’s 2020 progress report to parliament.

The Shared Mobility report is referenced in Local Government Association guidance for local councils on how they should/could deliver their net-zero carbon commitments (see separate case study on the LGA). Report author Prof. Greg Marsden is on an expert advisory panel at Leeds City Council, supporting their consultation on a strategy – including shared mobility – to make Leeds a city where no-one would need a car.

Shared Mobility was well received by the DfT. Feedback confirmed that policymakers were “actively using the findings and recommendations in their work” as they developed a policy framework on shared mobility. The ideas and concepts have been influential in broadening the Government’s role in shared mobility from being around innovation to “honing in to focus on the environmental impacts with the aim of feeding into the Department’s Decarbonisation Plan”. In July 2021 the Transport Decarbonisation Plan (pdf)Opens in a new tab was published which included an aim to increase average vehicle occupancy by 2030.

The Carbon Budget Delivery PlanOpens in a new tab quantified (Policy 135) the impacts of increasing average vehicle occupancy as an average annual saving of 0.5MtCO2e per annum in Carbon Budget Period 5 and 0.7 MtCO2e per annum in Carbon Budget Period 6.

The report has also been well-received by industry. Enterprise Holdings (the largest UK car club operator) has funded a PhD student to look at what areas would most benefit from new car sharing options.

Project team

Sources of information


I’ve already had some great follow up from attendees, so fingers crossed this is the start of a serious focus on reducing commuter emissions. Adam Jones of Liftshare, on the feedback he received on the day he took part in a webinar with local authorities on parking and decarbonisation.

Publication details

Marsden, G., Downing, C. and Eeles, A.K. 2020. Shared mobility: the case for fewer cars, more sharing. Centre for Research into Energy Demand Solutions. Oxford, UK. CREDS case study.

Banner photo credit: Alireza Attari on Unsplash