The final blade on the 123rd wind turbine was hoisted into place by crane and fitted to the turbine hub by the rigging crew last week, the final construction piece of the Cooper Gap Wind Farm.
Cooper Gap has a capacity of 453 megawatts and will generate 1.51 million megawatt hours of renewable energy, enough electricity to power about 260,000 average Australian homes.
The farm is already generating 182MW of power from 96 turbines linked to the Powerlink substation which feeds into the state's electricity grid.
The development is located some 250km north-west of Brisbane near Cooranga North, between Dalby and Kingaroy.
"The scale of the achievement is underlined by the fact that each of the blades are more than 60 metres long, the nacelle housing the generating parts weighed 90 tonnes, and they were lifted more than 100 metres into the air hundreds of times to be fitted," AGL head of construction Brian McEvoy said.
"About 200 people from the GE - Catcon consortium worked on site at the peak of construction work but this will wind down to about 20 once operations begin."
Cooper Gap is likely to be ramped up to full capacity in the coming weeks.
The Queensland Resources Council welcomed the completion of the construction phase, and said it was a "leading example" of coexistence between the Australian oil and gas industry and renewables sector.
"Queensland can thank the coal seam gas industry for investing more than a billion dollars in upgrading the transmission infrastructure across the Darling Downs which enabled a whole second wave of renewable investment to follow behind the gas industry," QRC chief executive Ian MacFarlane said.
"By adding Coopers Gap to the mix, Queensland will further consolidate its role as a heavy lifter in the National Electricity Market."