Energy Accounts and Billing

Help with your AGL Energy account or AGL online tools.

Help with your AGL Energy account or AGL online tools.

Hot water billing confusion.


We moved to an apartment 6 months ago after living in a larger home with 4 gas appliances, we had a bill shock with our hot water in our apartment. After finally working out some answers to my bill I was rather shocked how the hot water from the boiler to my apartment is calculated it appears I have a hot water meter under my kitchen sink that measures the amount of hot water used as this water meter has a heat sensor on it. This meter measures kilo litres and litres so when I use hot water the odometer moves to show usage. The units on my bill show decialitres then multi 10 which I believe converts back to litres used then conversion factor of.4666 something then coverts in to mj. Since I have finally figured this out I am worried about using my hot water. Am I misguided here feeling I am being charged in a fanciful way a cent a litre. Mj usage 12,000 for quarter previous in house average 7,000mj



Hi there, 


If they can not explain the non technical multiplication factor of 10 which so far Distributor is not in a position to justify, Please do not agree. Your start and end read indicated in the bills should refelect exactly as it appears on the meter registers, nothing more than that. So far only explanation that they give is this is the industry practice. This is not acceptable at all. Please lodge a complain with EWON on line and keep a diary of everyting. 


Please let me know whether you have any units of measurment is printed on your hot water meter. 


Hi @Dragons and @Village


Thought we'd jump in again - we've had a chat with our billing team to get you more info on centralised hot water systems and how they're billed. 


We've taken an educated guess (since you've mentioned the NSW Energy Ombudsman) and assumed you're in NSW. In NSW, centralised hot water is measured in litres and not the normal gas units (cubic meters). So the usage is multiplied by 10 (10L = 1 cubic metre of gas) and then by the common factor to determine the amount to be charged. 


Hopefully that sheds some more light on your enquiry. Let us know if you have further questions. 





If I've helped at all, a Kudos would be appreciated 🙂


Hi there, @sugarkane


Your finding from the billing department is not correct, let me give you the engineering behind this.


1m3 = 1000Liters= 1 Killo Liters (KL)


Hence 1m3 (Cubic Meters) = 1 KL


These are the unites of volume such as Water.


The Hotwater meter black registers are KL or m3. just forget about the red registers which is in Liters.


Now lets take an example, my consumption is 1 unit (that is diffrence between current read and last read) this is 1 m3 or 1000Liters of water usage.


According to your formula ie. 10L of hot water requires 1m3 of gas, let's calculate the required amount of gas for 1000 Liters of water (equal to 1m3) usage.


10 Liters Water need 1m3 of gas

1000 Liters Water need (1/10)*1000= 100m3.


So what did I do here, dvided by 10 and mutiplied by the usage. 


It is proved here that mutiplying by 10 is wrong based on the billing team formula.


This is where our billing is in correct and and no base or scientific reason to use the muliplying factor of 10.


I am ready to challenge this.


Of course the conversion factor used in my billing is 0.335826. This is another problem how this factor is calculated for the quarter. Infact I know this is based on the all the usage of the occupants in the apartment. When the hotwater usage is multiplied by this factor we can get the Gas energy used in MJ. This factor is called also the common factor. We should see how this common factor is determined and it will be interesting.




Hi Sugarcane

Thanks for your post, in your explanation to how much gas to heat litres, I am a bit taken back that it takes 1 cubic Meter to heat 10 litres of water? I am sure that my cooktop couldn't use that amount of gas to heat 10 litres of water. Please reconfirm this value. This for me means 10 litres x 10 x common factor= 1.39 dollars for heating 10 litres of water?


Hi Dragons, I also am confused about the meter. I drew off exactly 10 litres of hot water and took a before and after reading and the meter moved 67 units on the red dial. Can you tell me what I'm looking at here? If it's litres shouldn't it register 10 since I drew off 10 litres of water? AGL don't seem to be able to provide me an answer.


Hi Dragons

Sorry for later response more than 2 days, meter was at the back of my kitchen cupboards.My hot water Meter has m3 printed on it, with an arrow in the !middle between black and red this relevant?

hi ivy. Apparently you have done a dosage test to check the meter calibration using 10L of water. Theoratically the difference between last read and current read the red decimal register should increment only by 10 units instead of 67units as you found. No one else have should use at the same time. If your test is conducted correctly it can be assumed that the meter is not accurate. You can also repeat the test. Also another point is 10L may not be sufficient to check the resolution of the meter. The accuracy should come with in 2 percent. If you are not satisfied please lodge a complain with EWON if you are in NSW otherwise the appropriate Ombudsman in your state. Hope this clarify.

hi village. You have confirmed your water meter reads in cubic meters. that means black digits reads in Kilo liters. 1m3 is eqal to 1 kl or 1000l. thanks.


Hi Dragons

Thanks for quick response, my bill says I used 2,580.99 units, ( no disciption of what these unit are on my bill) my start read was 30,388

End read 32,968.99. My self Meter read was 329.689 on the last billing day, which if I subtract start and end  read I therefore  my read used 258.09 Kilolitres.

If the Meter used KILOLITRES should I be then be charged in litres, KILOLITRES or m3 as it appears that I am being charged for litres, when they use the mult 10, sorry for the trick question but no one knows how I should be billed including the retailer, wholesaler or any other agency.Just need clarification so I can really challenge this form of billing. Your insight is gratefully appreciated.

hi village. hope you are now convinced with the units of measurement of the meter. M3 or Kl it's same. Its true none of them are in a position to justify MF 10. You would have read our previous postings. This why I am challenge this issue with the Ombudsman. Infact I have more issues with the meter reading apart from MF application. It's so unfortunate that we can not get any explanation from the distribution network as they are responsible for the correct metering operations.