Alexander Dennis has unveiled the first members of its in-house battery-electric bus range in the form of the small Enviro100EV single-decker and the Enviro400EV double-decker. In doing so, the manufacturer has articulated a belief that the line-up will be as capable, versatile and popular as its existing diesel bus products.
The 11.1m Enviro400EV is a crowd shifter, says Alexander Dennis Group Engineering Director Chris Gall. President and Managing Director Paul Davies meanwhile describes the 8.5m Enviro100EV as “having a place in every fleet,” particularly noting its suitability to rural routes. Both have been designed around the needs of passengers and operators, adds Mr Gall.
In a further reflection of existing diesel products, the company believes that the newcomers will be “portable assets” that can move between applications across their working lives. The OEM talks confidently of that being 20 years, with claimed battery longevity and finance options supporting such an assertion.
Design language of the buses is described by Mr Gall as being akin to “modern architecture,” although he believes that they retain the recognisable characteristics of Alexander Dennis vehicles.
The former Jaguar Land Rover man is clear that his background in the car sphere has influenced the approach to the new range. “I felt that bus design before was based on engineering needs, with passengers fitted around them,” he explains. “I was keen to change that and put passengers first.”
Enviro400EV built on battery placement, says Alexander Dennis
On the Enviro400EV, one of the keys to design strategy is battery location. Packs are spread around the bus, with a concentration within the floor, as is also the case with the Enviro100EV; there, they are ‘nested’ inside chassis rails to protect them from damage.
A focus for Alexander Dennis was placing the batteries as far forwards as possible on the Enviro400EV to minimise imposed weight on the rear axle. Battery boxes within the floor are mounted on dampers so no chassis flex is transmitted.
Impact Clean Power Technology of Poland has supplied the batteries for the Enviro100EV and Enviro400EV. NMC chemistry is used. Mr Gall says the requirement for slim packs to go within the chassis dictated that choice, but he does not rule out using other chemistries on the later Enviro200EV, which will have greater scope for placement.
A characteristic of the Enviro400EV is a lower deck aisle that is flat as far as a step-up to the back row. Space and layout at the rear of that saloon is good. Two wheelchair user bays can be accommodated and one- and two-door layouts are possible.
Heights of 4.2m or 4.3m are available, and an open-top version will follow. Maximum passenger capacity is 96, with 80 seated. Expected range is 260 miles with 472kW/h of batteries, and 195 miles where 354kW/h is specified.
In 472kW/h iteration, the Enviro400EV is claimed to have an overall battery energy throughput of 1.4 GW/h before that storage requires replacement at 70% of original capacity. Alexander Dennis believes that the 1.4GW/h figure is 40% higher than any competitor vehicle.
That total takes into account power input and output as a result of regenerative braking and is thus not directly related to overall energy consumption. But the OEM says that route modelling has shown that such a capability will allow the bus to complete two, seven-year Transport for London route contract terms before battery replacement is needed.
On provincial work where average mileages are higher, a 20-year life with one change of energy storage is projected. Alexander Dennis will provide a standard eight-year battery warranty on both the Enviro100EV and Enviro400EV, but it is willing to negotiate an extension of that to 12 years on a commercial basis. Vehicle warranty period is five years.
Enviro100EV and Enviro400EV already certified by Zemo
The acclaimed Voith Electrical Drive System is used in both the Enviro100EV and Enviro400EV, in its medium-duty and heavy-duty variants, respectively. The latter gives a peak power of 410kW and the former 260kW. Alexander Dennis says that will be ample for interurban work, with a maximum road speed of 60mph, subject to other factors.
Zemo Partnership has already certified the new models via its Zero Emission Bus accreditation scheme. For the Enviro400EV in 354kW/h form, energy consumption is listed as 0.90kW/h per km. With 472kW/h of storage, that figure is 0.91kW/h per km.
In specifying members of the new range, Alexander Dennis will work with customers and local authorities to model operational requirements via a multi-physics tool. Mr Gall adds that in addition to CCS2 plug-in charging at up to 150kW, both new models are compatible with optional pantograph-based opportunity replenishment via roof-mounted rails at up to 300kW.
Enviro100EV ‘will create new market segment’, says OEM
Perhaps most significant of the two new battery-electric buses shown by Alexander Dennis is the Enviro100EV. Mr Gall believes that it will “create a new market segment.” The manufacturer is already talking of the Enviro100EV as a successor for the ‘go-anywhere’ 8.9m Enviro200 diesel. As previously noted, there is future scope for it to be shortened below 8.5m, he adds.
“We saw a gap in the market for a small bus with a good range, a good passenger capacity and which is highly manoeuvrable,” Mr Gall continues. “So the Enviro100EV was born.”
While the bus is 2.35m wide, Alexander Dennis has used full-width seats. 25 are fitted, with a total passenger capacity of up to 45. A turning radius of 8.6m is claimed and the OEM says that the Enviro100EV will have the same 20-year design life as its bigger brothers.
236kW/h or 354kW/h of battery capacity can be specified. Zemo certificates give energy consumption of 0.66kW/h per km and 0.69kW/h per km, respectively; Alexander Dennis claims ranges of up to 190 or 285 miles.
However, it hints that further developments later will push range figures for the Enviro100EV and Enviro400EV higher. That is via work by Impact, which is “already planning a future iteration of NMC batteries for Alexander Dennis,” the vehicle OEM says.
Batteries on the Enviro100EV are under the floor and on the roof. It has the same cab as the Enviro400EV, which has been developed from the existing layout.
Small bus shell to be manufactured by partner in China
Assembly of the Enviro400EV will be focused on the Alexander Dennis plant in Larbert, where a new production line has been established. The first customer examples, for Stagecoach and Transdev Blazefield, are well underway, although they are likely to be finished before homologation of the model is completed. Hence, they will not enter service immediately.
The Enviro100EV reflects the OEM’s global footprint. Its shell will be produced in China by Zhuhai Guangtong Vehicle Manufacture Co, the partner that already builds Alexander Dennis vehicles for Asia Pacific countries. From there, shells will move to Scarborough for fit-out, including driveline installation.
That transport will be via ISO flat rack, which is possible via the Enviro100EV’s diminutive size. The model will be available to satisfy successful bids via the second round of the Zero Emission Bus Regional Areas scheme in England, and the Scottish Zero Emission Bus challenge fund’s second phase.
Over 100 orders have already been taken for the two new models, and the manufacturer says that a deal for the Enviro100EV from a London operator is approaching completion. The smaller of the two newcomers will be built for stock, and Alexander Dennis has sourced a finance partner that is willing to underwrite 20-year terms on both models
On other members of the new battery-electric range, Alexander Dennis has confirmed that the larger Enviro200EV single-decker has entered development, with launch expected in 2025. The first latest-generation Enviro500EV tri-axle double-deckers have already been supplied to Hong Kong customer KMB. Mr Davies says that model could be offered in the UK if demand warranted.
Demonstration of the Enviro100EV and Enviro400EV will commence once homologation is complete. Existing battery-electric buses produced via the BYD Alexander Dennis partnership are unaffected and that relationship and product offering continues.
For more on the new models and the Alexander Dennis outlook on them, including further comment from Paul Davies, see the November print issue of routeone published on Wednesday 15 November.
