Victoria warned against ‘very inefficient’ hydrogen buses after trial announced

Cambridge professor says grey hydrogen buses are expensive, ‘destructive’ and not a true zero-emissions solution

Australia’s push towards hydrogen-powered buses could lead to governments repeating costly and energy-intensive trials that have failed around the globe, an expert has warned.

The Victorian government last week announced two Australian-made hydrogen buses will be rolled out in Melbourne’s west as part of a transition to a more sustainable transport fleet.

They will be part of a trial of 52 zero-emission buses, of which 50 are electric. The Victorian announcement came as jurisdictions across Australia were trialling hydrogen-powered buses, amid a focus on electric vehicles, as they transition to emission-free transport.

But Guardian Australia understands the buses will run on grey hydrogen, produced using natural gas.

Currently about 96% of the world’s hydrogen is produced using coal (brown hydrogen) and gas (grey). The production of grey and brown hydrogen releases carbon dioxide and unburnt fugitive methane into the atmosphere.

David Cebon, a professor of mechanical engineering at the University of Cambridge, said hydrogen buses were expensive, inefficient to run compared to electric vehicles and not a “true zero-emissions solution”.

“It’s destructive from the point of view of emissions. It’s destructive from the point of view of the energy transition,” he said. “It’s destructive in terms of finances and the economy because you have to subsidise them in order to make them financially viable.”

Cebon, a member of the hydrogen science coalition, said hydrogen was inefficient because of the energy-intensive process.

“It’s very, very inefficient. And that means that you use a lot more energy in that process than if you just took electricity and you put it in a battery and then just ran a battery electric bus,” Cebon said.

Victoria’s hydrogen buses will service routes across Footscray, Williamstown, Moonee Ponds and Sunshine in Melbourne’s west. The government said the trial, involving six operators, would provide information on how no-emission buses perform, including energy usage.

The government said the hydrogen fuel cell buses were estimated to save about 90 tonnes of emissions annually, as they only emitted water vapour at their tailpipe.

Prof Scott Hamilton, from Monash university’s department of chemical and biological engineering, said buses should use green hydrogen, which needs to be independently certified.

“If it’s not, the emissions profile can end up worse than if you were using petrol or other fuels because of the use of fossil fuels and electricity,” he said.

Hydrogen-fuelled vehicles can travel further than electric vehicles without requiring recharging.

From 2025 onwards, all new buses bought for Victoria’s public transport system will be zero-emission vehicles. Queensland has committed to the same action for its south-east fleets while ACT has a territory-wide pledge. NSW has a plan for all buses in the greater Sydney region to be electric by 2035.

Cebon said electric buses were becoming the standard globally and should be Australia’s preferred alternative to diesel vehicles.

He said the capital cost of a hydrogen bus was typically at least double the cost of an electric bus, while the running costs were at least three times more.

Cebon said trials of hydrogen-powered vehicles around the world had failed, including in the UK, Germany and France.

Alison Reeve, deputy program director for energy and climate at the Grattan Institute, said electric vehicles were the best option for city buses in terms of costs and emissions. But she said hydrogen buses for longer distances had the benefit of faster refuelling

“The Australian context is often different to a lot of other countries because of distance and population density,” she said.

“You can get a bus from Darwin to Adelaide and that’s a really long trip and it has to refuel several times along the way and there’s limited electrical infrastructure along that route.”

A spokesperson for the Victorian government said six operators across Victoria would take part in the $20m zero-emissions bus trial in Melbourne, Traralgon and Seymour over three years.

“Each technology offers unique advantages,” the spokesperson said. “Electric buses have the potential to excel in shorter routes and urban settings, while hydrogen buses boast longer ranges and quicker refuelling which may make them more suitable for heavy-duty and longer-distance application.”