I don't know if you're doing it on purpose but Minjur is one of the most controversial sites in the desalination debate because of how much its bankrupting the government to fund it for such little water back. It's funded because of political necessity in SPITE of economic viability.

We just literally don't have the technology yet. It takes an immense amount of electricity/energy to desalinate ocean water which is way more saline than brackish water. The other half of the cost is in the very high rate of corrosion of equipment.

I'm not against desalination of oceanwater. I absolutely support funding more research into it. I'm just explaining the current state of technology. It just doesn't currently exist.