right list of heaters, 1 300 watt, 2 100 watts, 1 150 watt and 1 50 watter. so thats 600 watts in total for heating the tanks. yes the heat pump is huge 9 kw.. i know it uses a lot of power and my partner has it on 24/7 quite high but having a $800 power bill in november is a bit excessive.. yes it was a reading and yes they have added what was missed for the esitmates from the last two months but thats about $50 each month from what i've worked out from the contact website. thankfully with the online ontime payments and stoping a paper bill we have a 22% discount. our biggest one was about $950 this year.. for me my partner and a 3 month old that is bloody huge!