Retrofit of older bus models to Euro VI with selective catalytic reduction (SCR) systems that under-performed has been blamed by the City of Bradford Metropolitan District Council (CBMDC) for it having failed to meet legal limits for air quality in a handful of locations.
A report to the local authority notes how there remain three locations that do not comply. In 2022, that number was 36. The city’s Clean Air Zone (CAZ) was introduced on 28 September of that year.
Papers that went before the CBMDC Regeneration and Environment Overview and Scrutiny Committee on 16 December observe that “the failure of bus [Euro VI] retrofits has had a significant impact on our ability to meet [air quality] compliance.”
Concerns about the performance of Euro VI SCR retrofit equipment in some bus fleets first came to light in 2023 after evidence showed that it may not have been reducing NOx emissions to the anticipated levels.
The Clean Vehicle Retrofit Accreditation Scheme was paused at that time, with a report later stating that of around 3,500 buses examined, a previously-cited 80-90% reduction in NOx was achieved in only around a third of them. Funding for such retrofits was subsequently ended and compliance and reporting requirements for existing systems tightened.
In Bradford, the local authority papers of 16 December note how following a conclusion that the below-expected performance of the retrofit equipment was contributing to a lack of compliance with legal limits in some areas, the Joint Air Quality Unit (JAQU) made available £8 million towards further zero-emission buses in the city.
That is part of a dual award alongside £20 million for Sheffield. It also has a CAZ. Transdev Blazefield has already converted routes into Bradford to battery-electric with funding from the Zero Emission Bus Regional Areas scheme to 15 Mercedes-Benz eCitaros.
The JAQU money will go towards replacing buses that operate along Manchester Road and Manningham Lane in Bradford, with an earlier study having shown that legal air quality limits on those roads can be met with such a shift.
The £8 million will part-fund 79 battery-electric buses for First Bradford and installation of associated infrastructure at its Bowling Back Lane depot. Those vehicles are for introduction by April 2027. Following rollout of bus franchising in West Yorkshire, the number of zero-emission buses at Bowling Back Lane will rise to 96 in 2028, and 144 by 2031.
