Geothermal needs very high thermal gradients. These are much...

Geothermal needs very high thermal gradients. These are much higher in areas with thinner earth crust or active subduction zones. The top 16 countries on this list all sit in either volcanically active areas or on the edge of plate margins (or both). Thankfully Australia is in a very tectonically stable plate (no volcanoes and very minor earthquakes) - the downside is that it makes Australia, generally, a poor area for geothermal power due to lower heat flow. There will be pockets where it is higher - maybe Perth basin is one but no one has made a commercial project there yet. Lots of R&D to come first.