Solar has a much higher upfront cost than coal, so it's much easier to finance a coal plant than solar one. That said, this is a better excuse for poorer, developing countries than Australia.
Yes, the WACC (Weighted Average Cost of Capital) explains why it made financial sense to roll out solar PV in northern European countries before many sunnier areas.
But as you say, Australia has no such excuse, having both the geography and the cost of capital to be a world leader in this, way beyond what they are now, which is okay but could have been much, much better.
Also points to an easy way to provide assistance to any country that is trapped into this financial dead-end.
