Hyundong,
I see that you are from SA.
You should be worried more about the fact that SA Power Networks are doing estimated reads.
An estimated read is given when the meter reader does not have access to your meter box.
Normally this is because of a locked gate and you are denying access to the property, another reason is that you may now have one or more animals in the yard that the meter reader does not feel comfortable entering the yard with.
Your Bill states that the reading period is only 29 Days which indicates that you probably only recently moved into it (Also note that your next bill is due after about 60 days.)
Your 905 meter has 58355 on the bill and your photo shows 58997
906 meter has 38960 on the bill and your photo shows 37881
Now it has been a week since you lodged this post so 18 days since your bill.
18 days and 29 days now makes 47 days
So your average daily use for your 905 meter is (based on your start reading on bill to your current true reading "the photo") 945kw / 47days = 20.11 kw a day so your reading on the 25 March should have been about 29 * 20.11 or 583 kw used or a meter reading of 58635 so 300Kw less than you have been charged for.
Your 906 meter is something different again according to your meter photo and the actual bill you have used -816 Kw which is not possible. (This is -17.4 Kw a day). The only logical assumption I can make of this is that there are solar panels connected to this meter
Could you take some photos of the meters again with actual dates supplied.
Cheers Neil
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