Driving up air quality

Electric buses are being slowly acquired or trialled by fleets across the UK as operators come under growing pressure to help improve air quality in urban areas in particular.

Some analysts believe that electric buses could be cost-competitive with diesel within the next decade and significant numbers are now operating in the UK. Steve Banner reports

Guildford’s atmosphere looks set to become a little cleaner now that Stagecoach South has put nine battery-powered BYD/ADL Enviro200EVs into service. With a range of 150 miles between recharges, the Surrey newcomers are on park-and-ride work.

On the other side of London, and demonstrating that battery buses are not just for major fleets, GO-Coach has been trialling an electric Optare Solo in Sevenoaks, Kent. It can travel around 120 miles before its battery pack needs charging up again.

BYD’s involvement in electric buses in the UK serves to underline the progress Chinese manufacturers have made in this sector, and it is not the only Chinese brand making its presence felt in Britain.

In South Wales, Newport Transport has been sampling a Yutong E12, which has received favourable feedback from passengers says the operator. It is smooth and quiet, they report, so there is a positive story to be told about reduced noise as well as air pollution.

Battery buses are cheap to operate. Running on route 8 in and around Sevenoaks town centre and recharged overnight, the electric Optare has consumed less than a tenner’s worth of electricity a day.

Although government grants can sugar the financial pill, battery buses are not cheap to acquire. That could change over the next decade however predicts Bloomberg New Energy Finance.

In a report published last year – Electric Buses in Cities – it states: “Our analysis of battery cost curves indicates that electric buses will reach unsubsidised upfront cost parity with diesel buses by around 2030. By then, the battery pack in the average e-bus should only account for around 8 per cent of the total e-bus price – down from around 26 per cent in 2016.

“However, increasing demand for e-buses could bring e-bus battery prices down faster,” it continues. “In this case, electric buses would reach cost parity with diesel buses by the mid-2020s.”

If you are going to operate battery buses then you have to have the necessary charging facilities in place. That can mean a massive change to the depot they call home, which may have been refuelling diesel buses for many years.

It can also mean calling on the e-bus manufacturer concerned to help you make the necessary arrangements; not something that would be built into the equation if you kept acquiring diesel buses instead.

RATP Dev’s Shepherd’s Bush garage in London has undergone just such an upheaval and now has the ability to recharge the 36 Enviro200EVs that are based there. They are being deployed on routes C1 and 70 which are being converted to full electric operation.

BYD was closely involved in installing the required infrastructure. At its heart is the company’s Smart Charging Management System; an automatic charging set-up which allows the garage to recharge all the Enviro200EVs simultaneously overnight with minimal supervision.

Energy group SSE – Scottish and Southern Electricity – installed the necessary power and data cables and the related wiring.

RATP Dev aims to turn Shepherd’s Bush into a depot with an all-electric fleet, but it is not there yet.

Go-Ahead’s garage just behind London’s Waterloo Station is however, and is home to 46 Enviro200EVs sharing 43 charging points. Charging is managed in such a way that none of the vehicles loses out.

Once again BYD and SSE were involved in establishing the necessary facilities along with UK Power Networks.

“One consequence is that we have no need to make use of opportunity charging,” says Go-Ahead London engineering director Richard Harrington. In other words there is no requirement to plug the buses into charging points for a few minutes during layovers to top up the batteries.

While electric buses are gradually becoming better established, the situation with electric coaches is more problematic.

Buses invariably return to their home depot at night, but coaches do not always do so – especially if they are on touring work – and may travel long distances. That raises questions of range and where they plug in either during their journey or when they reach their destination.

BYD is persevering with electric coaches nevertheless. It currently has one on trial in Germany with Flixbus on a 60-mile-plus route between Frankfurt and Mannheim via Frankfurt Airport and Heidelberg.

It tackles this journey four times a day recharging once or twice. It uses 80kW charging stations in either Mannheim – there is one at the central bus station – or Frankfurt.

The trial will last a year and the coach should clock up over 78,000 miles.

Liquefied natural gas (LNG) could represent an environmentally-friendly alternative, at least compared to diesel. Last year’s Hanover Commercial Vehicle Show saw Scania unveil the LNG-powered Interlink Medium Decker coach, said to offer a range of over 600 miles.

“While there are several options for carbon-conscious city and suburban bus operators, there are fewer alternatives for businesses in the long-distance travel market,” says head of buses and coaches Karin Radstrom. “That’s a lack we’re now addressing.

“It’s a timely and viable alternative now that LNG is becoming increasingly available throughout Europe as well as in many other parts of the world,” she adds.

Diesel is likely to dominate the coach market for some time to come though, and operators with Euro 5 models face a problem. They may not want or be able to afford to replace their vehicles with more modern Euro 6 coaches just yet; but tougher emissions regulations set to be rolled out by city authorities across the UK that favour Euro 6 may compel them to do so.

Nor is retrofitting a Selective Catalytic Reduction Technology exhaust after-treatment system that will bring their existing coaches up to Euro 6 standard necessarily an easy option as it is with diesel buses.

Eminox, Amminex, (Eminox handles the latter’s products in the UK), Baumot, Proventia (which works through Mitcheldean, Gloucestershire-based Excalibre in the UK) and HJS have all introduced systems for buses. Coaches are produced in smaller volumes however and their designs can differ significantly from one model to the next, so a suitable package may not be available.

Eminox however has come up with a package for Volvo’s B9R. By doing so it has become the first and to date the only company to gain approval from the Clean Vehicle Retrofit Accreditation Scheme for a coach system.

Plaxton has gone on to successfully complete a trial which it says demonstrates that what Eminox has to offer can be used to upgrade Euro 5 Elites on B9R chassis to Euro 6. “It has also been developed to upgrade other models such as Leopard and Panther,” says Plaxton and ADL used vehicle sales manager Jamie MacIntosh.

Eminox points out that the introduction of the London ULEZ is putting a strong focus on Euro 6 emissions standards compliance. “Companies have limited options if they want to operate in London after 8 April 2019,” says an Eminox spokesperson, “they can buy new vehicles, pay a daily fee, avoid the ULEZ, or retrofit. The ULEZ is just one of a growing number of clean air zones and low emission zones being planned or implemented across the UK – wherever you are based, now is the time to look carefully at emissions compliance.”

As the only company to currently provide a CVRAS-accredited coach system, Eminox is in a strong position and one customer that it says is already seeing the benefits is Lucketts Travel which is retrofitting its Volvo B9R fleet with Eminox’s exhaust aftertreatment system to dramatically reduce NOx, while meeting the stringent emissions standards of the ULEZ.

Eminox’s rivals are working on gaining approval for products suitable for coaches too, but progress is slow.

HJS is developing packages for Mercedes/Caetano and DAF/Van Hool applications, but they will not appear before the middle of this year.

Excalibre says it should soon be able to offer CVRAS-approved products for selected DAF-powered models. Baumot is also working on systems for a number of coach models.

While gas may be in its infancy so far as coaches are concerned, it has made significant progress in the bus market.

Fifty-three biogas-fuelled Scania/ADL Enviro400CBG City buses are in service with Nottingham City Transport (NCT); the biggest fleet of gas-powered double-deckers in the world. The contribution they have made to cleaning up the city’s atmosphere is believed to be one reason why plans for a Nottingham Clean Air Zone have now been scrapped because there is no longer any need for it.

Meanwhile Van Hool buses fitted with hydrogen fuel cells have been in service in Aberdeen for some time and other bus builders are starting to offer the technology.

Last year saw ADL announce that it was adding hydrogen fuel cell models to its line-up. It has developed a prototype hydrogen Enviro400 in conjunction with Arcola Energy.

Opt for gas buses and – as with electric buses – a properly-thought-out refuelling infrastructure is vital. Roadgas has installed gas dispensers in NCT’s Parliament Street depot, positioning them next to the diesel pumps so that both types of vehicle can be refuelled.

Gas is starting to find its way into the minibus market too.

Last year Luton, Bedfordshire-based Blue Bus Innovations acquired three compressed-natural-gas-powered Iveco Daily Line Hi-Matic 50C14GA8 16-seaters. They are being deployed on a shuttle service between Luton Airport and central London, which will see the introduction of the Ultra Low Emission Zone in April.

The ULEZ will be expanded out as far as the North and South Circular Roads in 2021.

Says Blue Bus managing director Tazio Puri Negri: “While we strive to offer our customers the best service, we are also aware that we need to minimise our impact on the environment; and with emissions restrictions set to get even tougher, we will look to increase our fleet of alternative-fuel minibuses.”

Leave a Reply

Your email address will not be published. Required fields are marked *