Alexander Dennis continues to promise much for its next-generation Enviro200EV battery-electric single-deck bus, which will break cover in 2025.
What the manufacturer says will be class-leading seating capacity and energy consumption are among items that it believes will deliver strong market share for the product, which sits alongside the existing Enviro100EV small single-deck and next-generation Enviro400EV double-deck models.
Head of Concepts and Advanced Engineering Jamie Wilson explains that while the Enviro200EV shares a lot with those other vehicles, it also leans on the strengths of the Enviro200 diesel. In current form, that bus debuted in 2015, but it in turn traces its roots as far back as the late-1980s in the Dennis Dart.
Low weight is a hallmark of the Enviro200 and its iconic predecessor, and that has been key for the Enviro200EV since it was laid down as a concept in late 2022.
But much more is shared with its contemporary zero-emission sisters, including design language inside and out. “We took a high-level view of our next-generation battery-electric range because those models have a lot of commonalities,” Jamie says.
“We tried to make them modular as far as possible rather than designing three products for the UK that are each new from the ground up.”
Weight reduction at the fore for Enviro200EV
On minimising weight, he adds that a key element is right sizing the drivetrain. The Enviro200EV will come at lengths of 9.9m, 10.9m and 11.7m in provincial and Transport for London (TfL) configurations, with a 10.4m option to TfL specification only.
GVW will be 17,200kg against a maximum passenger capacity of 92 in provincial format, which Alexander Dennis notes gives a 1,800kg saving over many competitors in the full-size single-deck space.
Jamie adds that as far back as the Dart, lightweight single-deckers have performed well for the manufacturer and its predecessors. The basic philosophy for the next-generation Enviro200EV is “quite faithful” to the Enviro200 diesel, although the battery-electric will gain independent front suspension.
The cost of that equipment is less than before. Alexander Dennis is mindful that a lighter-weight design risks magnifying poor road surface intrusion into the vehicle and is more susceptible to rattles.
Independent front suspension helps to mitigate those factors, and the manufacturer is confident that ride quality will be good. Jamie and his team have also carried out a lot of work on maximising structural stiffness.
Up to 43 seats planned for newcomer
Much else is being done on the Enviro200EV from a passenger perspective. It will introduce new design elements beyond those common with the Enviro100EV and Enviro400EV. “We recognise that with those vehicles, we needed to move quickly to get them to market, and so most of our styling work was on the exterior,” Jamie explains.
“For the Enviro200EV, we had time to consider the interior in detail with respect to passenger experience and ambience.” Key to that is the platform area, which he describes as “the lobby.”
An inviting proposition for boarding customers is important, and what is seen first on the full-size single-decker is expected to find its way to the other battery-electric vehicles over the next two years.
A lightweight approach translates into the layout of the passenger area. As seen on the Enviro100EV, small wheels minimise intrusion. The Enviro200EV will ride on 19.5-inch wheels compared to the 22.5-inch diameter of competitor models.
“A bus is for passengers, not to carry a drivetrain,” Jamie notes. “The floor area, not weight, is the limiting factor when it comes to maximising seating and standing capacity.
“Reduce wheel intrusion and you have more space to carry people. That is an approach that has served us very well in diesel single-deckers and we believe it will do the same in the Enviro200EV.”
At 11.7m to provincial specification, a maximum of 43 seats will be possible. With two wheelchair user spaces, that will drop to 41.
In TfL configuration, Alexander Dennis says that the Enviro200EV will have between two and five seats more than competitor vehicles and, the builder claims, will be the only larger single-deck battery-electric product that can meet the tendering body’s target capacities. A midi-based approach is again key to that, Jamie says.
Urban and interurban use of Enviro200EV considered
A major area of commonality with the Enviro100EV and Enviro400EV is use of the Voith Electrical Drive System (VEDS).
That product’s efficiency has been lauded, and in the ‘virtuous circle’ surrounding weight and energy consumption, it means that 400kWh of battery storage has been judged to give the optimum range. A move away from hub motors also means that the traction package is entirely sprung, which will reduce vibration.
VEDS will be available in the Enviro200EV in medium-duty or heavy-duty form. Jamie expects that the former will account for most examples manufactured, but the latter is part of the portfolio to account for interurban requirements where higher average speeds are in play. The heavy-duty iteration of VEDS is already used in the Enviro400EV, where 60mph can be achieved.
Lithium iron phosphate (LFP) chemistry in batteries sourced from CATL has been adopted for the Enviro200EV. That is one area where it varies from its range-mates. The other two buses use lithium nickel manganese cobalt (NMC) technology owing to space constraints.
The Enviro200EV has significant roof space for energy storage and hence packaging is not as critical. LFP is thus most appropriate. Battery warranty will include up to 1.4GWh total energy throughput.
Jamie notes that on the 11.7m variant, energy capacity could be increased, while across the board it could be reduced should a customer require. However, neither is likely to be necessary, barring highly unusual use cases.
That expectation comes via the use of route modelling, with Alexander Dennis having a ‘deep dive’ tool that goes into significant detail on each customer’s needs.
Class-leading energy use predicted by Alexander Dennis
That modelling has also given predicted energy usage and range for the Enviro200EV. Figures are not yet for public consumption, but Jamie points to its Enviro400EV sister having achieved the lowest consumption for a battery-electric double-decker under Zemo Partnership testing as a strong indicator of what is expected from the newcomer.
“We hope to mirror that in due course with the Enviro200EV,” he explains. “We have almost two tonnes less to move than competitors, and we will do so with the most efficient driveline on the market.”
97% grid-to-wheel efficiency is promised, as with the Enviro100EV and Enviro400EV. A first Enviro200EV is expected in Q3 2025, with Zemo testing to start soon afterwards, subject to availability of slots.
While LFP battery chemistry is what the Enviro200EV will debut with, Jamie adds that thoughts have already turned to future technology generations for energy storage. With the promised efficiency and versatility within a lighter vehicle, there are no plans for a full-weight Enviro300EV single-decker for the UK to follow.
Manufacturing location awaited
Alexander Dennis President and Managing Director Paul Davies has made clear his view against use of subsidy to part-fund zero-emission buses manufactured outside the UK. There is no final decision yet on where the next-generation Enviro200EV will be assembled.
But a spokesperson for the business points out that at present, “the market does not reward us for building buses in the UK,” which is the reason for the body of the Enviro100EV coming from a partner in China.
“We assume that market conditions for the Enviro200EV will be similar, so we are pursuing the same approach for now,” they add. Even so, the new model could be built entirely in the UK, although any supplied to Asia-Pacific markets will be manufactured in China as a matter of course.
Clearer is that Alexander Dennis has high hopes for the new model. It will arrive next year into what is already a competitive marketplace. Battery-electric technology in bus has advanced far beyond its position when full-size vehicles in that field began to appear in 2013. Such a pace of progress, exemplified by what is promised of the Enviro200EV, shows no sign of slowing.
