Alexander Dennis has revealed the first member of its latest-generation battery-electric bus range that is to Transport for London (TfL) specification in an Enviro400EV double-decker.
It is a demonstrator and will be made available to operators later this year after completion of homologation and certification. A TfL-specification Enviro100EV battery-electric small single-decker will follow “shortly,” and the builder advises that the larger Enviro200EV under development “will cover all other TfL vehicle requirements.”
The Enviro400EV has been shortened to meet London needs. In that form it is 10.5m long compared to 11.1m in the provincial model. Such an exercise has been carried out to assist manoeuvrability, and turning radii are 10.1m and 10.8m, respectively.
In London format the bus has a wheelchair user bay accessed via the centre door. The demonstrator has 62 high-backed seats, with four abreast on the rear row in each saloon to benefit comfort. With 472kWh of batteries overall capacity is 87 passengers, while with 354kWh up to 96 people can be carried.
Alexander Dennis Group Sales and Business Development Director Ben Werth underlines that the energy storage is warranted for 14 years or one million kilometres, whichever comes first. That will cover two full TfL route contracts and give a major benefit to total cost of ownership, he adds.
“For the TfL Enviro400EV, there is a design sweet spot that optimises available energy and therefor range, as well as vehicle efficiency, length, weight, and passenger capacity,” Mr Werth continues.
“In addition to detailed route analysis, we have conducted extensive tests with our supply partners at the cell, module, pack and vehicle level, which has shown that 99% of London routes can be fully services with our 472kWh battery.”
The manufacturer says that charging can be undertaken in as little as three hours via a DC connection, or faster via optional roof-mounted rails for inverted pantograph-based opportunity replenishment.
Power is taken via the Voith Electrical Drive System, which as the German OEM recently revealed has already seen 1,000 units deployed among UK users. Vehicle manufacturers including Alexander Dennis have lauded that product for its efficiency.
The latest-generation Enviro400EV satisfies UN Regulation 155 on cybersecurity. Although not mandatory in the UK, such compliance “ensures that the vehicle is protected against malicious attack and that customers’ data is securely hosted within the country,” Alexander Dennis says.
Mr Werth adds that while the Enviro400EV in current form can operate almost all TfL routes, a battery roadmap shows growth in energy density that “points towards needing fewer batteries in future to deliver the same total energy at an even better total cost of ownership.”