Vestas, the company building the project, confirmed the incident.

“The site has been closed and we are working closely with emergency services and the authorities,” the organisation said in a statement.

The rotor blades used in the project are more than 80m in length, according to the Vestas website.

Three unions, the Australian Workers Union, CFMEU and Electrical Trades Union, had warned Vestas of safety concerns in the weeks leading up to the event, Australian Workers Union state secretary Ronnie Hayden said.

“This devastating loss could have been prevented,” Hayden said.

“Just two weeks ago, union delegates from three different unions met with Vestas management to raise serious safety concerns, telling them it was only dumb luck that nobody had been killed on site yet.”

The union accused Vestas of transferring safety obligations on to subcontractors who lacked the necessary training.

“This is not just another statistic, this is a worker who went to work and never came home,” Hayden said.

“We need more than just investigations and reports, we need immediate action on site safety and stronger enforcement of regulations.”

Speaking at a press conference in Melbourne, Victorian Premier Jacinta Allan expressed her sympathies and noted the state had strong workplace safety regulations.

“Any accident in any workplace is indeed a deep concern and a tragedy,” Allan said.

Once completed, the project will be the biggest wind farm in the southern hemisphere, producing more than 4000 gigawatt hours of energy each year, about 9% of the state’s current energy demand.

The project’s first turbines were connected to the grid in October in a launch by state Energy Minister Lily D’Ambrosio.

The wind farm has planning approval for up to 228 turbines, the current design comprising 215 turbines across 16,739 hectares.

In April, another wind farm worker was killed after falling 20m from a wind monitoring tower at a site in Queensland.

WorkSafe is investigating and police will prepare a coroner’s report.