Looking back on the post from 2019, it's hard to fathom how a small home with one adult one child could have received such a bill amount, this is before the period over the last 2 years or so when power costs have soared.
It'd be interesting to see how @Kaleidoscope got on with this with no further posts.
As for the thread awakening from @Dianneleroux you might need to get someone in to do a power audit, some power companies can do this, varies state to state, and there are private organisations that do it too.
Eg. AGL apparently do this for customers in Victoria ?
I just googled > power energy audit < and had a quick browse.
You can do some checks on various appliances yourself, there are simple powerpoint meters that measure what something plugged in is using, 2 quick search (power consumption meter) examples . . .
https://www.jaycar.com.au/mains-power-meter/p/MS6115
https://www.bunnings.com.au/arlec-energy-cost-electrical-meter_p0586167
I would look really close at your bill first.
Where are you using most KWH of power ?
At what times ?
If something looks very high, it's worth looking hard at that first.
If you have a few basic skills in analysis, you can possibly use meter readings when using power, and record some before / after figures, check readings before bed and in the morning, again middle and end of day etc, see if there are any large usage amounts of power used overall in the home.
A lot is going to depend on what state you are in, what plan, the tariffs, and then the metering, whether still on single tariff, possibly with CL if you have electric HWS, or if you are on TOU tariff which can be complex with best times to do household power using chores.
You should hope you aren't on a demand tariff, some are being moved to this, moreso in some QLD regions this can really be unfair in the way it charges a peak demand cost over an entire billing period peak demand, just from one single peak high usage.
States, pricing, plans, tariff structures, metering, it can all make one persons situation far different to anothers.
Very hard to work out what's going on, and most people don't have the time, desire, or willingness to get through all the cloudy modern power charging discrepancies.
