That sounds about right.
For the average Australian user, it means you add ~ $200-350 / year to your effective ISP cost. Not end of world for most, but certainly not trivial for all, either.
The regrettable history of Australian internet provisioning (specifically our national broadband network) and electricity pricing (specifically the rorts and corruption, and higher-than-rest-of-world pricing) are described much more eloquently by others.
in your case about $16.74 if you subtract 25% for the estimate of benefit from your solar (grid tied?) kWh going back to the grid