Swiss-made metro vehicles struggled with Brisbane’s climate during trial

The new Brisbane Metro vehicles were not designed for the city’s climate, internal Brisbane City Council documents reveal, but City Hall is confident the issues identified during last year’s trial run have been rectified.

Documents obtained by this masthead through Right to Information legislation show a mostly successful trial period for the new electric bus service, with some issues that could – and should – have been foreseen.

But despite the teething problems, council public transport chair Ryan Murphy said the trial had been a “raging success” – an assessment borne out by internal feedback from passengers, who gave the service an average overall satisfaction rating of 4.3 score out of five.

Passengers onboard the first official Brisbane Metro service.Credit: Courtney Kruk

“Brisbane Metro is a first-in-class, all-electric, bus rapid transit system, but even with the best-laid plans, technical issues can crop up when a vehicle is initially deployed,” Murphy said.

“That is part and parcel of every major public transport project in history.”

The council documents reveal the airconditioning in the 24.4-metre electric buses at times struggled to cope during the month-long trial period late last year, due to “CC200 limitations”.

The CC200 is a power management unit that runs on-board systems, such heating, ventilation, cooling for the cabin and batteries.

“[Swiss-based bus manufacturer] HESS’s base design has not taken into consideration the ambient operating conditions for Brisbane environment, i.e. passenger cooling is compromised to prioritise battery cooling even at higher ambient conditions,” the council documents show.

A council spokeswoman said HESS updated CC200 software so it could better balance the load between air conditioners and vehicle battery cooling systems.

BCC public transport chair Ryan Murphy.Credit: Cameron Atfield

Passenger feedback was varied.

“There are some areas that are very cold under direct aircon flow,” one otherwise ‘very satisfied’ passenger reported to the council, while a ‘somewhat satisfied’ passenger said: “The metro needs better aircon because it was still quite hot but besides that it is amazing.”

A ‘somewhat dissatisfied’ passenger said: “Aircon usually warm on warmer days even if metro was not full.”

There were also numerous complaints about the chairs being uncomfortable or hard.

The documents also identified issues with the vehicles’ 24-volt system design and performance, which power a number of low-voltage systems on the buses.

“Overall 24-volt system capacity exceeds under certain load conditions, such as all [heating, ventilation, and air conditioning] units operational, battery cooling operational and steering pump operational,” the documents show.

The first official Brisbane Metro service, travelling the 169 route from Eight Miles Plains during the trial period last year.Credit: Courtney Kruk

“HESS’s base design does not have a 24-volt load control system.”

The council spokeswoman said there was no load balancing in the initial design, as “the HESS design did not require it”.

“Power draw for Brisbane’s subtropical environment required the implementation of load balancing and this was undertaken by HESS in a software update,” she said.

Murphy said the council was satisfied with how the issues had been ironed out.

“We’ve been pleasantly surprised with how quickly we’ve been able to work with our suppliers to fix these issues, with teams in Brisbane and Switzerland working to steadily improve the vehicle as we entered service,” he said.

“The first two stages have already been hugely successful, and Lord Mayor Adrian Schrinner and I are incredibly excited to launch more Brisbane Metro services from June 30.

“Together with Brisbane’s new bus network, Brisbane Metro will help us make the leap from public transport to mass transit, delivering an additional 160,000 services every year.”

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