OP again. US$300 is a lot, but fairly typical here in SA. We regularly hear of families in our area paying AU$1500 per quarter (around US$1300) for electricity. But then we also see families with more TVs than actual family members, reverse-cycle airconditioners running all day and other sorts of outrageous waste.
Pricing has been seen as a means to reduce consumption in Australia. It's a valid approach, but it does hit people hard - particularly those who can't afford it - but by and large it has been effective. But it has also lead to an oversupply of electricity generation, so now the Carbon Tax has been removed it's possible we'll see a return to higher consumption. It's hard to tell if people's behaviour has changed during the period when the Carbon Tax was in force.
As a side note, as a point of comparison, we only pay around US$150 per month for a four-person household (inc. one teenager). We don't go without - everyone has their own computer, there are multiple tablets in the house. We're just careful about leaving things on that don't need to be on.
South Australia's climate also lends itself to better energy use. Winters are mild and because we have a very dry climate, evaporative air conditioning works really well here in Summer (and costs very little to run). We have the highest uptake of residential solar power in the country, thanks to a high number of days with sunshine. Solar panels are also mandatory on all State government buildings, including a large array on top of our Parliament House. I'm not actually from SA originally, but I'm quite proud of the place I call home. Far from being a "backwater", South Australia has been quietly leading the way for a long time.