> Natural gas is a fossil fuel, though the global warming emissions from its combustion are much lower than those from coal or oil. Natural gas emits 50 to 60 percent less carbon dioxide (CO2) when combusted in a new, efficient natural gas-power plant compared with emissions from a typical new coal plant.
From the above natural gas power plants do produce a surprising amount of CO2, but is far far better than new coal plants. Legacy coal plants also are a significant air pollution source, so if we get out of coal power plants by building out natural gas seems like a win.
Finally I checked renewables for South Australia and they seems to be doing really great at 53%, compare to U.S. at ~23%: https://indaily.com.au/news/science-and-tech/2021/01/27/sa-r...
List of currently operating power plants and the ones under constructions corroborates renewable energy percentage and actually suggests that South Australia is doing great on renewables: https://en.wikipedia.org/wiki/List_of_power_stations_in_Sout...