Finding the cause of power usage

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Aaroona

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#259773 21-Oct-2019 13:40

Our power bill comes to around 160-190 usually per month (mercury). For 3 people in the house, that seems *about* right, though still a bit high for me- reasons detailed below.

Over the course of the last few months, I spent the majority of my time overseas (3 weeks out, 1 week in NZ), which meant I wasn't home to use power. The power bill barely dropped.
Then my other flatmate has been away for about 3 weeks, and the bill still came to 160.
The third flatmate is barely home and barely uses many devices or electricity when they are home. Additionally, this flatmate replaced the previous person we had in who was VERY frugal with energy consumption and who was only home maybe 2 nights out of 7.

So I'm starting to wonder if there is another cause of the electricity bill. It seems to fluctuate around the 560-590kWh a month.

Is there any way of tracing what could be the case? The house is a 90's build, so not exactly new and I really couldn't comment on wiring.

SirHumphreyAppleby

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#2341371 21-Oct-2019 13:56

Hot water leak? An increase in power usage is usually the first indication we have of a problem.

wellygary

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#2341401 21-Oct-2019 15:02

First up $160-$190 a month is pretty good for a flat of 3,

What's the summer/Winter variation on that..?

Unless you are on a low user plan your daily charge over a month is likely to be upto $2/day, so in reality you only have $100-$190 in variable changes to reduce....

Do you have a power app from you power company so you can track your usage?... ( It saves having to run outside to check the meter when you are playing around)

you should be able to see spikes in demand based on when you bath/shower cook/heat

Assuming its an all electric household, the biggest demands are hot Water, heating and then cooking...

tripper1000

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#2341402 21-Oct-2019 15:02

1) Does the bill state weather the invoice is based on actual readings or estimates? One of my friends received estimated readings only for 24 months, so his billing did not accurately reflect fluctuating usage. Most retailers will accept an actual reading over the phone from the customer if they don't have an actual reading from the meter reader.

2) If your bills are actual readings have you matched the power meter readings in the bill with your power meter? If they don't match you might be getting sent a neighbours meter readings by mistake which would also explain why it isn't fluctuating as expected.

3) I know you said the power co is Mercury but do you get the power bill direct or via the landlord? If this via the landlord you are likely on a shared meter and your billing will be based entirely off of the landlords division of the bill - I'm aware of several places like this.

Aaroona

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#2341424 21-Oct-2019 15:55

SirHumphreyAppleby:

Hot water leak? An increase in power usage is usually the first indication we have of a problem.

Good question. Anecdotally we have had other issues re. water in this place, and it often took ages for hot water to come through and had a few tap leaks (but that was for cold). I will go around and check all the taps, etc and fittings the cylinder.

wellygary:

First up $160-$190 a month is pretty good for a flat of 3,

What's the summer/Winter variation on that..?

Unless you are on a low user plan your daily charge over a month is likely to be upto $2/day, so in reality you only have $100-$190 in variable changes to reduce....

Do you have a power app from you power company so you can track your usage?... ( It saves having to run outside to check the meter when you are playing around)

you should be able to see spikes in demand based on when you bath/shower cook/heat

Assuming its an all electric household, the biggest demands are hot Water, heating and then cooking...

As I mentioned, 190 was barely with 3 people there, it was more like 2.

In the last place I was in with two people, the bills were around 110, sometimes less, per month. (but also different provider etc. Definitely way less total kWh usage though).

I unfortunately don't have access to the app. the head tenant might, I'll ask him. The bill is direct from Mercury. It says (act) on the bill, so presumably that means actual reading vs. guessing here- (est).
would definitely be interesting to see when the spikes occur. Myself and the other flatmate barely cook at home at the moment. But even when we were, the power usage again barely changed (maybe $10 max)

The main flatmate who cooks at home almost daily hasn't been there for over 3-4 weeks, yet no real change in usage.

Looks like I need to do some digging around what electrics are running in the house, just to be sure. I'm not going to go on a crusade, I appreciate 190 isn't huge, but given the changes in usage patterns and corresponding lack of change in charges, it just seems a bit odd.

Aaroona

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#2341426 21-Oct-2019 15:57

tripper1000:

1) Does the bill state weather the invoice is based on actual readings or estimates? One of my friends received estimated readings only for 24 months, so his billing did not accurately reflect fluctuating usage. Most retailers will accept an actual reading over the phone from the customer if they don't have an actual reading from the meter reader.

2) If your bills are actual readings have you matched the power meter readings in the bill with your power meter? If they don't match you might be getting sent a neighbours meter readings by mistake which would also explain why it isn't fluctuating as expected.

3) I know you said the power co is Mercury but do you get the power bill direct or via the landlord? If this via the landlord you are likely on a shared meter and your billing will be based entirely off of the landlords division of the bill - I'm aware of several places like this.

1. It says (act) which I assume means actual.. I will have to double check in the Mercury FAQ's if that's what it means.

2. Will have to find where the power meter is, thanks for the suggestion.

3. Direct from Mercury (via the landlords email). Its a town unit in a block of units. They are all separately metered.

PolicyGuy

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#2341432 21-Oct-2019 16:18

Aaroona:

tripper1000:

2) If your bills are actual readings have you matched the power meter readings in the bill with your power meter? If they don't match you might be getting sent a neighbours meter readings by mistake which would also explain why it isn't fluctuating as expected.

2. Will have to find where the power meter is, thanks for the suggestion.

There is probably a 'meter cupboard' or similar where all the meters are housed together.

In case you are getting charged for somebody else's electricity and they are inadvertently getting the benefit of your frugality:

check the meter number printed on the bill is the same as the meter number on the device itself.
If they match, check that the meter you are being charged on is actually the one for your flat - it is not impossible that the meter marked "Flat 1" is actually connected to "Flat 2" (or 3 or 4). You may need to coordinate with the other flats and turn off "your" meter to make sure it is actually yours.

Good luck
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wellygary

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#2341436 21-Oct-2019 16:30

PolicyGuy:

check the meter number printed on the bill is the same as the meter number on the device itself.
If they match, check that the meter you are being charged on is actually the one for your flat - it is not impossible that the meter marked "Flat 1" is actually connected to "Flat 2" (or 3 or 4). You may need to coordinate with the other flats and turn off "your" meter to make sure it is actually yours.

You should be able to find the correct meter by matching or getting close to the Kwh reading on your bill...

tripper1000

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#2341439 21-Oct-2019 16:34

Don't forget that with Mercury on a Standard user plan you will paying at least $66 in fixed charges (base on a Auck address) so this mutes somewhat your power consumption swings. Actual consumption costs could be swinging nearly 300% from $40 (on a ~$100 bill) to $110 (on a ~$180) bill.

$120 is in the realm of normality for one person, so your bills don't seem large.

Moderate cooking for 1 or 2 people doesn't use a lot of electricity in the big scheme of things (boiling a pot of spuds, frying a steak etc), that is unless you are doing a lot of baking and having 3 hot meals a day etc.

The single biggest users of power is space heating and water heating. 10 extra minutes in the shower will user more power than cooking the spuds. If the absent flat mates normally have short showers the effect on the bill will be far less than when someone who has long showers is away.

wellygary: You should be able to find the correct meter by matching or getting close to the Kwh reading on your bill...

You mean, you should be able to find the meter that you are being billed for, not necessarily the meter that is measuring your flats consumption.

Delphinus

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#2341455 21-Oct-2019 17:22

I'd also locate your meter and then turn as much stuff off in the house as possible and check the current usage stops as expected. Eg leave appliances off for an hour when you're all out and ensure there is little to no change in kWh usage.

WyleECoyoteNZ

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#2341457 21-Oct-2019 17:50

Does seem very high, considering the amount of time away you've detailed.

We're a family of 4 (2 adults & 2 kids) and we were away for a week in July, and average power usage for the week we were away was around 7kWh a day (entertainment unit devices in standby and HRV system running). Got those numbers from the Contact Energy website usage stats.

Generally a month, usage is anywhere between 520 - 670 kWh, it's lower due to LPG gas for hot water heating and cooking.

It could be that the thermostat on the hot water cylinder is faulty, and if's constantly heating the hot water, this could explain the higher power bills.

ANglEAUT

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#2341474 21-Oct-2019 18:23

Aaroona: Our power bill comes to around 160-190 usually per month (mercury). For 3 people in the house, ...

Ask your landlords to enable the weekly usage reports from Mercury. You'll get something looking like this

This report is delayed by 2 week unfortunately, but it does give you an idea at least.

Btw, we are 4 people in the house. 2.5 at home all day, 1.5 away for work. Our bill from Mercury is ±$260 in summer & ±$360 in winter.

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ghettomaster

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#2341568 22-Oct-2019 08:25

You need to use a process of elimination to understand your usage.

Firstly, if you can’t get into the website and look at your usage, start taking meter readings morning and night. Do this for a week or so to get an understanding of your current usage oattwrns.

Next, start looking into causes of high usage. As mentioned already your two biggest causes of usage is space heating and water heating. You are probably already aware and conscious of your space heating usage but check for the obvious. Do you leave a heat pump on all day? Does a flat mate have a heater in their room? If you’re trying to get to the bottom of the issue you’ve probably already looked into this but it’s worth a mention.

Next look at your hot water cylinder. After your week of baselining, try turning it off for a day and see how much difference that makes, and if it is about what you expect.

I had an issue in one flat where the hot water cylinder was low pressure, and the valve that feeds water into the cylinder was faulty. The end result was that hot weather was constantly trickling onto the roof then down the spouting. This constant trickle of cold water into the cylinder meant the element was never turning off. We nice I got it fixed my power bills went from 3-450 a month down to a more reasonable 100 and something so you obviously don’t have an issue as bad as that.

Once you have dealt with those two culprits, see what else you can find out about. You could get one of those piggy back meters where it will tell you how much power a given outlet is using but a typical entertainment centre or pc setup use about 100w or less, maybe a bit more for gaming.

Finally, if you can get into the website and see your hourly usage, this is even better. If your hot water cylinder is turning off and on, expect some hours where it’s a few kWh, and a few where it’s less than that. Try and work out what is happening and when and correlate it with that data.

Finally as far as ensuring you are using the right meter, if it is digital you can get it to tell you the current load. Turn something big on, like a heater or stove element, and ensure it goes up as expected. The hot water cylinder isn’t ideal for this test as it won’t draw any power if the hot water is above the required temperature.

ANglEAUT

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#2342192 22-Oct-2019 23:18

Aaroona:

Our power bill comes to around 160-190 usually per month (mercury) ...

Say thank you to dolsen, spend one months bill worth on these, plug them into anything & everything to confirm power consumption. 😂

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