Melbourne data centres could need 1,900 more diesel generators, researcher says

Dr Robert Ryan, an atmospheric scientist at the University of Melbourne, estimates that the city's growing data centre sector could need another 1,900 large diesel generators as backup, lifting diesel stored across its facilities to roughly 40 million litres. Ryan said about 300 of these machines already operate in Melbourne. His main worry was the western suburbs, where he said many lower-income residents already contend with pollution from traffic and heavy industry.

Ryan said Victoria's new planning requirements "definitely help", but they would not reach existing developments or some projects already in the pipeline. He called on operators to publish how many generators they run, when they test them and which coolants they use, saying thin information on testing and emissions makes it hard to judge the combined health effects on nearby communities. "We've got to start asking these questions before we make the investment," he said.

Ryan was among four researchers who spoke at a Melbourne Energy Institute forum at the Forum Theatre in Parkville on 22 October. It took place five weeks before the Victorian election, with the Greens seeking a moratorium on new developments and the Labor government having announced planning requirements, including a 150-metre buffer between new facilities and homes. Institute director Professor Richard Sandberg, who moderated, said Australia has about 165 operating data centres with more than 225 further projects under consideration, and that their combined operating capacity is projected to more than double by 2030.

Professor Pierluigi Mancarella, chair of electrical power systems at the university, said data centres can be delivered within two years while major transmission projects can take a decade. Planners, he said, must choose how much to build without knowing which proposals will proceed. Mancarella said, "Either you build too much or you build too little and you will miss lots of opportunities," describing the dilemma. His modelling suggested that siting data centres near renewable energy zones rather than around big cities, and moving some computing away from peak periods, could relieve strain on the grid and cut the new generation required.

Associate Professor Leslie Martin, an environmental economist at the university, said the electricity market does not fully charge users for the congestion they create on transmission networks. That means some data centre costs could be shared by other electricity users, she said, and she warned they could hit households least able to cope, such as renters and apartment dwellers who cannot fit solar panels or batteries. Martin doubted data centres would move demand to cheaper periods, saying she had seen "very little evidence of price sensitivity" in how they operate.

Professor Andrea Carson, director of the Centre for Advancing Journalism and Information Integrity, presented early research covering almost 130,000 Facebook and Instagram posts on data centres. She said civic backlash and calls for public oversight were among the most common themes, while government agencies, business media and investor accounts mostly backed expansion. Carson cautioned that social media activity is not a measure of public opinion.