what mattered was the energy usage comparison - latest usage vs usage one year ago
one year ago, for a similar period (within 2 or 3 days) the usage was 501 units for about 2 months - and the latest usage was 115 units.
the cost is 25c per kw plus gst - then the supply charge. the supply charge for the latest period was a few cents more than the cost of the eclectricity.