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Large vehicles targeted as new clean air measures take hold

•  Clean Bus Fund helps local bus fleets curb emissions
•  Coaches, vans, trucks striving to meet new city standards
•  Accreditation scheme ensures retrofits up to the job

Quality public transport services are a massive part of a low-carbon future – but that’s not to say that there isn’t room for improvement from the transport options currently available.

Cutting air pollution is a prime priority for towns and cities, and buses, spending a lot of time on the roads and often running on diesel, are a contributor to poor air quality.

full bus with man looking out the window with a newspaper

Technological additions can curb bus emissions

It’s heartening news, then, that more money has just been made available to retrofit cleaner technologies on to bus fleets in 20 local authority areas in England.

A total of 2,768 buses will benefit from lower emissions thanks to the £40million injection from the Clean Bus Technology Fund.

While the scheme is only available in England, there is money available for firms in Scotland to get help with retrofit through the BEAR programme, a pilot scheme using funds left over from the Green Bus Fund, which helped companies to buy new buses.

Certification Manager Colin Smith explained the rationale behind supporting change in this very familiar form of public transport. He said: “Local authorities are responsible for local air quality and have a degree of control over bus contracts and the vehicles operated, so can stipulate certain level of bus emissions performance.

“Though changing all buses to the latest emissions standards overnight would have a great impact, it would probably bankrupt the bus industry, and manufacturers probably couldn’t cope with the demand. What this funding means is that councils can now help companies with retrofitting their legacy vehicles and meet the standards required.”

Buses still best bet for urban transport

Smith is quick to add that even though funding is being put towards cleaning up older buses right now, they still represent an ultimately cleaner way to get about towns and cities – particularly where rail services are not available.

He explained: “If you look at buses’ emissions per passenger kilometre compared to a car, it’s a lot lower because you can get more people on board. The challenge is to get more people onto buses and out of their cars. Bus patronage has fallen in cities like Glasgow, which doesn’t help with congestion, and so, in a cyclical effect, discourages people from using them.

“Integrated transport networks do something good for cities. Utilising bus capacity then means they flow better. The experience on buses is changing based on people’s expectations, too, with some offering the option to charge up your phone or access Wi-Fi. There’s a lot of behaviour change elements that need to shift so people make more sustainable transport choices – and that’s part of the mission of Energy Saving Trust.”

Certifiably clean

The UK has been lagging behind European air pollution targets in a number of hot spots for some time now, so naturally, this new funding alone isn’t going to provide an overnight solution to a significant problem.

It is, however, a useful addition to a nationwide push to radically reduce harmful pollutants – part of which is the introduction of Clean Air Zones (CAZ) in UK cities. Diesel-using vehicles such as buses, vans, coaches and trucks entering these zones must comply with what’s known as the Euro-VI standard for exhaust emissions, or face financial charges .

Energy Saving Trust is currently working to certify emission reduction systems for fleets with these vehicle types that have opted to retrofit, rather than investing in new models, are coming up the mark through the Clean Vehicle Retrofit Accreditation scheme.

Going retro requires strict standards

Retrofitting exhausts is a more complicated business than it used to be, as NOx emissions reductions are required as well as particulate matter (PM), using what’s known as a Selective Catalytic Reduction (SCR) system. Then there’s the matter of different vehicle and engine types, performing slightly differently.

Smith explained: “Retrofit is one way of achieving compliance within a CAZ, if avoiding the zones or investing in new vehicles are not viable options. But you need to have trust in the retrofit product that you’re buying. So we’re there to provide trusted, impartial certification of these systems.

“However, you can’t test on one bus and be certified for them all – it doesn’t quite work like that. And when money is being given out for retrofits, funders want to know that the technology is working in the real world and on all vehicles where it’s installed.”

More modifications to come?

Buses are not the be all and end all when it comes to air pollution in our towns and cities, but at the moment, whether other types of vehicles benefit from any retrofit funding support remains to be seen.

Smith said: “Buses represent a relatively modest contribution to particulate matter and NOx emissions. The rest is cars, vans and trucks. There was £220million announced in the Budget to help local authorities improve air quality, so some may decide to set up other retrofit initiatives. But this could be difficult, as it’s hard to say that a truck, for example, is wholly working in a specific local area.”

Responding to a human – and legal – issue

Taking on retrofit in the transport sector now is all about meeting a present need. Smith added:

“The retrofit market does have a limited life, as vehicles eventually get replaced at the latest emissions level, so the market gradually diminishes. This replacement cycle will take some time, but the air quality situation needs to be acted on as soon as possible, as that’s the basis of Client Earth’s continuing legal case against the UK Government.

“Retrofitting to Euro-VI equivalence has an immediate impact. Once you’ve retrofitted a bus, for example, it’s cleaner. In the end, 40,000 die prematurely each year due to conditions related to air quality – if you wait five years for models to be replaced, that’s a real human problem.”

Gary Hartley is Energy Saving Trust's expert blogger. He has extensive experience researching and writing on a number of topics, with particular expertise in sustainable energy, policy, literature and sport. As well as providing regular blog content, Gary has also been published in numerous magazines and journals.