Electric Water Heater Running Costs

• 

  poboy on 31/08/2017 - 15:30

  Do you have a controlled load on your hotwater? Do you have halogen downlights? Are you using air con?

  Your supply charges may have also changed as you changed area. Compare to your previous area.

  Generally hotwater is about 30% of your elec bill. Does the hot water system have energy ranking info? Compare to a modern system.

  Good luck.

  • 

    AustraliaObscura on 31/08/2017 - 18:13

    Thanks for the reply.
    I'm a bit naive when it comes to these things, how do I check the load type? All I know is that the system is in the roof, so I might have to try getting up there and see if I can check out the energy ranking info too. I did ask the real estate agent some questions about it, and he kept insisting we had gas water heating, until we finally got a plumber to tell him!
    Even when we were away for 3 weeks, so no showers / hot water usage at all, our bill seemed continuous for that time.
    The supply charges are quite a bit lower here, so that's why we were even more shocked that the charges were so high.

    • 

      poboy on 31/08/2017 - 19:22

      Your electricity bill will note if you are on a controlled load. If not, perhaps ask your energy retailer if you can have one.

      A controlled load only applies to hot water. Your hot water is heated very early in the morning at a rate that is much cheaper than your standard electricity rate.

      • 

        AustraliaObscura on 31/08/2017 - 23:30

        I think we might have that, as when I looked at the Jemena electricity report (hour by hour view over days) the spikes seem to be all at 11:30pm. We're usually in bed then with no heaters or lights on, so I assume the water heating is done then. Just seems to be a spike of triple the amount at 11:30.

      • 

        Euphemistic on 01/09/2017 - 07:12

        @AustraliaObscura: that sounds 'normal'. Now you need to determine if you are getting a cheaper rate at that time. It should be cheaper becuase it is off peak.

      • 

        AustraliaObscura on 01/09/2017 - 13:10

        +1

        I rang the energy provider, they said we have a single rate, but with controlled rates between 11am - 7pm. The spikes seem to start from 10pm, so they said to get an electrician to check the time switch on the actual water heater system in the roof. We'll probably have to pay for it ourselves, can't see the landlord doing it when there is no specific problem.
        The electricity staff member I talked to said our household was using the same about as a 5 - 6 person household! Crazy.

      • 

        tunzafun001 on 23/07/2018 - 18:45

        @AustraliaObscura: This is 100% it. I have the same hot water service. But it is on its own controlled load circuit, not time dependent.

        To reduce costs it sounds like it comes on 1 hr early? you could try finding the breaker and turn it off for an hr to get back in sync. If the timer is independent, then it's call an electrician, or physically turn it off and back on manually after 11.

        Also, it's probably set on the side at 55 degrees. Dial it back to 48C or similar (but you will need to get in the roof to adjust).

        Lastly, I bought a twin door dishwasher from Gumtree for $150, as the kitchen sink hot tap basically has no flow. Twin door holds around 6 plates, 6 bowls, 6 mugs etc per half. Uses 6L water (less than a sink).

        My house is entirely electricity. Bill is sub $200 per quarter for 2.

        • Edit - I do like cooking with my butane camp stove (thanks supercheap auto for the free gas with $5 credits… Been a while though).
• 

  thetrain on 31/08/2017 - 15:32

  Probably electric hot water. it sucks

  • 

    [Deactivated] on 23/07/2018 - 19:08

    +1

    A mate of mine halved his hot water bill by switching the water heater on only when he needed it.

• 

  Euphemistic on 31/08/2017 - 15:50

  You say your electricity bills have gone up by $60/month but at the last place you were using gas for hot water and cooking. How much was the gas previously? ie was gas+electricity at the old house equivalent to electricity at the new?

  Double check what system the hot water is using: off peak (controlled load), or standard. Our off peak hot water uses around 4-7kwh per day which equates to $35-$60 per quarter on the cheap off peak rates for a family of 5. Variation is due to seasonal differences, lower usage in summer. $60/month increase seems quite high just for water heating.

  • 

    Nugs on 31/08/2017 - 16:04

    electric hot water;

    family of 5 - average per night from jan thru march this year is 7.2kwh

    unit is Vulcan 250 litre rated at 3.6kw and manufactured in 2006

  • 

    AustraliaObscura on 31/08/2017 - 18:31

    Thanks for your example and the reply. The gas and electricity combined was slightly lower before, but also we had two people cooking and showering before, whereas now it's hardly any cooking and one person showering during the week.
    How do I check the system, will it be on the water heater itself or through the bill / electricity company? Sorry, don't know much about these things but it is important for me to learn, I'm seeing!

    • 

      Euphemistic on 31/08/2017 - 19:45

      First place to check is the bill. Something else to consider is that the power company probably doesn't read the meter monthly, unless it is a smart meter, they might be averaging based on the old tenants.

      • 

        AustraliaObscura on 31/08/2017 - 23:32

        We have a smart meter. I just compared average bills between the new and old place, used to have a combined gas / electricity of $90 a month, now it's around $150 electricity, but with one less person.

• 

  3dgy on 31/08/2017 - 18:42

  Hot water system might need a bit more insulation on the pipes especially close to the heater, it is possible it is loosing heat through the piping during winter, also check to see if the overflow is leaking out a lot when the heater gets hot, perhaps the pressure relief valve is old.
  Has there been an increase in the daily connection charge with your electricity provider?
  Do you have induction stovetop - these sometimes chew a lot of power even when you are not using them - if they are faulty. You can try unplugging or swiching it off at the powerpoint under the bench, or get a clamp type amp meter to measure current on each of your circuits to see if there is a draw when you have everything turned off.
  Also if you have a printer or copier try switching that off at the power point as they use a surprisingly high amount of power when in standby.

  edit - also 2 months of running an electric heater - - what is the watt rating of your electric heater - how much do you run it? 2500w heater means 2.5kw per hour which would be how many cents/kw on your electricity bill?
  …say 30c/kw would equal 60c an hour!

  • 

    AustraliaObscura on 31/08/2017 - 23:44

    Thanks for the informative reply. I think you might be right, the house is quite old and a few things have already had to be replaced because of faultiness or old age (stove, toilet, etc). As we're only renters though, I doubt the landlord is going to care too much about doing up insulation or valves.
    No induction cooktop, printer or copier, but those are good ideas for future for me to remember.
    We have been running electric heater plus a reverse cycle sometimes during winter, but the bill has only gone up about $15 - $25 per month over winter months, so the bulk expense must be something else.

• 

  Stewardo on 03/09/2017 - 21:46

  My electrician said a 250ltr was about $100 a quarter.

• 

  PlumPro on 18/07/2018 - 07:30

  There are some great guides and tools for water heater consumption online try:

  Rheem's Cost Calculator
  Aus Grid Energy Calculator
  CMPS's guide to electric water heaters

  From my experience the main cause of high electricity bills which result from a hot water system come from an unnoticed leaking valve.