How the ZEBRA Scheme is Improving Oxford’s Air Quality
The Zero Emission Bus Regional Area (ZEBRA) scheme has transformed public transport in Oxford and surrounding communities, introducing 159 electric buses on 34 routes. The project was funded by the Department of Transport, Oxfordshire County Council, Oxford Bus Company and Stagecoach, representing a major investment in zero-emission public transport and Oxford’s journey to net zero.
The ZEBRA scheme is an important step forward to reducing carbon dioxide emissions. Furthermore, research has shown that the scheme is delivering tangible benefits to people’s health, wellbeing and their everyday experiences of the city.
Cleaner Air for Oxford
Air pollution remains one of the biggest environmental threats to public health in the UK, contributing to an estimated 30,000 deaths each year. Road transport is a major source of pollution in both Oxford and Oxfordshire, making cleaner public transport a key part of the solution.
The Oxford ZEBRA scheme was introduced in support of local ambitions to improve air quality and reduce traffic-related emissions. Early findings from an independent evaluation conducted by the PHIRST PHRESH Research Team suggest that the switch from diesel to electric buses is already having a measurable impact.
Annual average nitrogen dioxide (NO₂) concentrations across Oxford fell by around 10% between 2023 and 2024. In locations with particularly high bus activity, including St Aldates and the High Street, reductions reached up to 24%.
The residents interviewed as part of the study, reported experiencing fewer diesel fumes and less visible exhaust pollution on city streets.
Quieter Streets
Traffic noise is increasingly recognised as a significant public health issue, affecting sleep, stress levels and overall wellbeing. The transition to electric buses is helping address this challenge too. Researchers found that traffic-related noise levels in central Oxford reduced by an average of 5.1 decibels following the introduction of electric buses. To put this into context, the reduction is comparable to moving three times further away from a busy road.
Residents living along bus routes reported fewer disturbances and a more peaceful environment. The quieter operation of electric buses is helping create a cleaner and more pleasant streetscape for everyone who lives, works and visits Oxford.
Lessons for the Future
The evaluation highlights Oxford's success as an example of what can be achieved through strong collaboration between local authorities, transport operators and communities. Researchers identified partnership working, investment in charging infrastructure and comprehensive staff training as key factors behind the successful rollout.
While factors such as ticket prices, service reliability and route connectivity remain important in influencing travel choices, the scheme has shown that decarbonising public transport can deliver wider benefits for public health and quality of life.
Looking Ahead
The success of the ZEBRA scheme demonstrates the important role that transport decarbonisation can play in improving environmental quality and public health. Today, the 159 electric buses introduced through the scheme account for 69% of all bus mileage within Oxford. The evidence from the evaluation shows that this investment is already delivering measurable improvements in air quality, reducing citywide nitrogen dioxide levels and lowering traffic noise on some of Oxford's busiest streets.
This work contributes to Oxfordshire County Council’s Air Quality Strategy and Route Map. Moreover, building on this progress, Oxford City Council has recently adopted a new Air Quality Action Plan (AQAP) 2026–2030. The plan sets an ambitious new target to reduce annual average nitrogen dioxide (NO₂) concentrations to 20 microgrammes per cubic metre by 2030, a commitment known as "20 by 30". The target goes significantly beyond current legal requirements and reflects the council's determination to continue improving air quality and protecting public health.