Tranzit Group’s second successful “repower” bus or 3401 – a single deck electric bus that was successfully converted from diesel to 100% electric – is now delivering services on Metlink’s bus network in Wellington.
The innovative bus was made to show that repowered electric buses are a viable public transport option that can assist the country in reducing emissions from land transport.
Repowered buses are an extension of transitioning to a zero-emissions bus fleet and can also solve three problems at once, according to Tranzit’s director of transport and opertions Keven Snelgrove.
“Our two repower buses provide an alternative way for New Zealand to meet its public transport decarbonisation targets on time alongside building brand new, while addressing the issue of how to transition relatively new diesel bus fleets to electric so that operators are not left with stranded assets,” Snelgrove says.
“In addition, to having zero tailpipe or scope 1 emissions, a repower bus can mitigate scope 2 or indirect emissions that result from building brand new.”
The bus is the second successful converted vehicle, the first completed in 2021 in a Southern Hemisphere first.
“It’s great a second repower bus is in service. Metlink is aiming for all core bus routes to be electric-only by 2030 and for the complete decarbonisation of our bus fleet by 2035,” Metlink group manager Samantha Gain says.
The conversion was done by Tranzit’s Masterton based workshop team, removing a Cummins Euro 6 engine from the single deck urban bus and replacing it with 10 batteries that have a combined 350kwh.
These were placed in bespoke framing and brackets build by Tranzit’s engineers, and a fully electric air conditioning system was installed and is located on the top of the vehicle.
Tranzit’s team, who were involved in the first repower, spent weeks testing the vehicle including electrical signals that once came from the body, suspension and brake computers, but now come from the ev powertrain.
An extra challenge faced on this repower, compared to the double deck repower, was fitting the same number of batteries into the same space at the rear of the bus.
“You can certainly tell just by looking into the engine bay, that all the batteries are precisely positioned in their purpose-built framing and thanks to the reduced space are pretty snug, however we are really happy with what the testing showed us about its performance,” Tranzit’s Masterton eorkshop manager Gareth Price says.
“Our first repower bus, which was a Southern Hemisphere first innovation, took around six months in total but allowed us to develop a blueprint for further repowers which proved invaluable on this one.
“We are proud of the work we’ve done and it’s great we’ve been able to lead the way from regional New Zealand.”