Without or with Solar is farily easily to compare on energymadeeasy.gov.au . . .
If you have a digital meter with 2 years of data, then you can put your NMI number in there and it will work it out on your 2 years of data, very accurate.
(You can do it for gas too same time if you have that, otherwise click electricity only.)
If you have an older analogue meter (unusual for new solar, usually it's an 'upgrade'), then you have to look at the tariffs from different retailers and do some sums based on your plan tariffs with Alinta.
If you got a battery too, that is a whole different matter, as these comparo sites can't compare the amount of variables there are.
For that, I would google sommething like > what electricity FIT plans are available in (your state) for evenings
Adding - small retailers - to that search can bring up minor retailers entering the market and offereing quite high rates for 3 - 4 hours in peak time.
AGL has a different approach, offering things like the VPP and battery rewards.
All the best with the solar . . . know that the way things are now, or changing fast, without a battery you will really only benefit from solar only if you can self consume . . . if you were on a single tariff plan, and now moved to a TOU (time of use) plan, you can still be ok, you just have to use power in the home to bet suit your TOU periods for cheaper power, usually through the 1000 - 1500 type time.
If you work all day, TOU will probably cost you a lot MORE than older bills, if that's the case ask to be moved back to a single tariff if possible, just make sure where you are your DNSP does not have a demand charge for peak times, not knowing how that works can cost you really big $.
It a crime really that the electricity market is so complex now.
Best of luck.
