Alexander Dennis presents new generation of electric buses

On 1 November 2023, Alexander Dennis (ADL), a subsidiary of the Canadian New Flyer Group, presented the latest generation of its electric buses at the company headquarters in Larbert, Scotland. The midibus “Enviro 100 EV” and the double-decker “Enviro 400 EV” were presented. Both belong to the large family of new, completely emission-free buses from Alexander Dennis and, according to the company, mark a significant step forward compared to their predecessor models.

They are completely new designs from the ground up, which is also reflected in the new look of the vehicles. According to Alexander Dennis, this will enable the transport companies that will put these buses into service to effectively draw attention to their commitment to emission-free public transport.

The Enviro 400 EV double-decker is 11.1 metres long and is primarily intended for use on busy city and neighbourhood routes. Alexander Dennis certifies that it has a range of 420 kilometres.

Its little brother, the Enviro 100 EV, is an 8.5 metre long single-decker that is only 2.35 metres wide. According to the manufacturer, it is particularly easy to manoeuvre and also fits through narrower streets. Alexander Dennis puts its range at 460 kilometres.

At the presentation of the new buses, ADL Chairman Paul Davies pointed out that change in the bus industry is now taking place at a remarkable pace. Alexander Dennis in particular can now draw on seven years of experience in the construction of electric buses.

Technological aspects of the new buses

ADL developed the new emission-free drivetrain in-house. Voith Turbo is contributing its “Voith Electrical Drive System (VEDS)”, which is designed for medium loads in the “small” Enviro 100 EV and for high loads in the double-decker. The double-decker in particular can also reach higher speeds.

The batteries work with nickel-manganese-cobalt (NMC) cell chemistry. They have found their place both in the chassis and in the rear of the two new types, and in the double-decker also under the stairs to the upper deck. The installation under the floor of the coach in the chassis protects them from being damaged in the event of an accident. Should the batteries ever need to be replaced during the “life” of the bus, “standardisation” of the installation spaces ensures that the replacement can be carried out easily. And should future batteries become larger in order to give the buses more range, the installation spaces are designed in such a way that larger batteries can also be accommodated here.

The low-floor lower deck of the double-decker offers 19% more space than its predecessor. There is more legroom on the seats. Unlike other double-deckers, the stairs to the upper deck are not angled and are therefore completely straight. Alexander Dennis says that this is not only more practical, but also safer.

The windscreen on the upper deck has been designed as a “panoramic window”, which provides a good view to the front. And “skylights”, or “windows to the sky”, can be installed in the roof of the vehicle.

The newly designed geometry of the front in the area of the driver’s seat not only protects the driver better in the event of an accident, but also other road users. Designer Chris Gall: “We have transferred design principles from car construction to the bus. The new generation gives the driver improved visibility and the front section offers improved active and passive accident protection.”

Both new bus types are equipped with the latest driver assistance systems. Warnings are not only visualised at the driver’s seat, but also audible. And a “speed limiter” ensures that the driving speed always remains within safe limits.

As Alexander Dennis also wants to deliver to London, safety specifications from TfL (Transport for London) have been incorporated into the new design at ADL. This has already been honoured by TfL with the “TfL Supplier Award”.

Extensive warranty services, low life cycle costs

Alexander Dennis emphasises the low operating costs for both types over their entire service life. In addition, very high warranty claims are granted. ADL offers an eight-year warranty on the Enviro 100 EV and Enviro 400 EV batteries. The manufacturer expects that the trolleys will be able to run for 20 years in typical London public transport services and will only need to have their batteries replaced once “halfway through”, i.e. after ten years. 

The production sites

It is interesting to note that the double-decker will (be) built in Larbert, while the small “Enviro 100 EV” will roll off the production line in Zhuhai, China. Production has been taking place in Zhuhai for 15 years now, and the plant there has long been fully integrated into ADL’s production network.

The next steps in the introduction of the new generation

For the “international markets”, the new generation of the double-decker “Enviro 500 EV” is to follow shortly – as it runs in the diesel version in Berlin. ADL recently delivered the first vehicles of the new Enviro 500 EV to Hong Kong.

The “international version” of the Enviro 100 EV is currently being built in the design offices in Larbert. While single-door (!) buses dominate in the United Kingdom and Ireland, the international markets demand at least two, if not three-door buses. A bus with only one door – even if it is double-width – could not be authorised in Germany.

Alexander Dennis also wants to launch the new Enviro 400 EV double-decker as an “open-top double-decker”. There does seem to be a certain market for city tour double-deckers.

In 2025, ADL wants to add the new Enviro 200 EV, a single-decker in the 11 to 12 metre class, to its new generation of battery buses.