Victoria's summer energy supplies will be boosted by a new power station at Mortlake in the state's west.
The $810 million plant near Warrnambool is the largest gas-fired power station in Victoria.
It runs on natural gas from the Bass Strait and can be switched on and start generating power within about five minutes at times of peak demand.
The plant can generate up to 550 megawatts of power.
Premier Ted Baillieu says the plant will not reduce Victoria's reliance on brown coal, but it will make electricity supplies more stable.
"This adds a significant contributor to the generation capacity in this state," he said.
"Obviously it's a peaking plant, it's servicing a very particular need, but it has long term prospects as well." Energy Minister Michael O'Brien says the plant will protect the state from blackouts on days of extreme heat.
"With this extra 550 megawatts of peaking power which can come online at very short notice, it means that when we get those very hot days, those spikes as we experienced last week, Victorians will be better placed than ever before to cope with that this summer," he said.
Origin Energy will run the plant.
The company says the station has the capacity to supply the equivalent of peak power to 250,000 homes.