Dunedin e-bus trial tackles hills no sweat

A Dunedin electric bus trial has come back with positive results and mitigated battery power and range concerns especially around more hilly areas. 

The Otago Regional Council (ORC) and Go Bus Transport began testing the vehicle in October on Dunedin’s public transport routes including hills, the city centre and motorways. 

The city provided a much hillier testing terrain compared to Auckland and Christchurch were the buses are already operating.  

The 35-seater Enviroline bus was built by Global Bus Ventures in Rolleston and the one-month trial set out find what challenges might arise with the introduction of EV buses there. The results were presented to the council’s implementation committee on December 8. 

Transport implementation advisor Abbey Chamberlain says during the trial, the bus used between 40-50% of battery on a full day of service and performed well on hills. 

More of the battery charge was consumed on steeper hills and when the air conditioning was used, though the braking of the vehicle regenerating energy partly compensated for increased battery consumption.

“We found out that this type of electric bus can operate well on a large part of Dunedin’s public transport network. Battery usage was not an issue, and the bus worked well on the different types of terrain.

“We also now have a better understanding of weight restrictions for heavy vehicles such as electric buses, which are heavier than diesel buses – largely due to the vehicle batteries. 

“Passenger feedback was overall positive about decarbonisation and most people were excited to see more electric buses in the future,” Chamberlain says. 

Go Bus chief executive Calum Haslop says he was “very happy with the outcomes” of the trial.

“Being able to bring one of our electric buses to the city for a month provided an opportunity to see how the EV bus performed on hillier suburbs, which we don’t see in Auckland or Christchurch. 

“As expected however, they posed no problems and drivers told us that the EV drove up steep streets with ease. The drivers loved driving it and are sad to see it go. 

“As a result of the trial, we have confidence that electric buses can easily be part of Dunedin’s public transport future, and Go Bus looks forward to the opportunity of bringing zero emission buses to Dunedin, permanently,” Haslop says. 

One of the main challenges identified in the trial was navigating some of the road infrastructure. This includes bus stops and key intersections, which require more precise driving due to the longer wheelbase and wider turning circle of larger buses. This issue was overcome during the trial with careful driver training.

The electric bus is estimated to have saved 2,511kg of CO2 emissions over the course of the trial, without taking into account other CO2 savings from reduced car usage. That is more than 90% reduction in CO2 emission compared to regular diesel buses.

The e-bus travelled a total distance of 3148km, carrying over 3000 passengers.

The heavier weight of the vehicle was not an issue for the trial even though it exceeded weight restrictions for some bridges in Dunedin –  those bridges were not located on routes operated by Go Bus.

Councillors at the implementation committee endorsed a subsequent report due next year to consider next steps towards a zero-emission public transport fleet.