@dhuy42,
The supply charge is set by your Supplier (Energex I presume,listed on the top of your bill), it has nothing to do with AGL (your retailer) who simply collect this on behalf of them.
I live in SA and our prices are double yours (or maybe more), but I only pay 109c per day.
Nothing to do with AGL and the good thing is if you go on holidays and turn off all the power you will still pay the supply charge for the whole time, for a 90 day bill period you will pay $130.50 for supply charge.
Cheers Neil
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