No it is not. Can you quote a source or a dollar per MwH figure?
I looked in to solar at my place, no battery it would take eight years to break even on install costs and that assumes the feed in tariff does not fall again. With a battery it would be about 14 years to break even. Solar panel life is 15-20 years, inverter probably less.
The fact I have solar panels and they paid themselves off in 3 years.
Australia has gas and coal a plenty. There is no reason foreign influence exists other than only WA had a domestic supply reserve. All states should have a domestic supply reserve. Once again various federal and state governments have failed to look after the interests of Australians.
Just because you have coal and gas means nothing, it still has to be found, land purchased, machinery and plant procured, dug up, transported to the power plant, burnt in relatively expensive facilities, ash disposed of so it doesn't create an environmental disaster, sulphurs captured and disposed of to prevent large acid rain cloud formation in the lee of the stacks. Then there's cost of transmission and power loss to transmission because you don't want a coal plant anywhere near an actual city for obvious reasons.
The average actual life of a coal power plant is usually only 30 years, so having a solar panel on your roof that lasts 20-30 years is on par. Replacement of a coal plant is about $3 billion per 1000MWH. It costs around $1million per 1000 MWH just to start up a plant that's been shut down. Then the fuel runs at about 10000 tons of coal per station MWH per day. Because Victoria uses the worst coal on the planet stations like Loy Yang burn 60,000 tons of the stuff per day.
Then there's the health and environmental effects, areas of coal power generation have significantly higher respiratory disease than other areas, especially if using open cut mines. The cost for treatment of coal related disease in generating areas in Australia is estimated at around $2 billion per year.
I could go on and on about how expensive coal electric power is, its insanely expensive in an complete overview, but the plants appear cheap to the simple minded layman. But when you add the total economic cost of everything associated with them they are terrible.
PS We should have gone nuclear years ago. It integrates with renewables much easier as the output can be varied, where as coal costs a lot to power up and down stations, it increases wear and tear significant and adds a lot to maintenance. So yes renewables are making coal fired power more expensive as well.