Smart Meter query

[stevemul]

Please bear with me. Out of interest and annoyance with the Utility Companies, I have installed a DIY solar system which is giving me about 1Kw of electricity per day in the current time of year and will give me over 2Kw per day in the summer. It is totally independent of my house supply. I have been trying to find the best way of using my " free" 1Kw per day and I decided to closely monitor my smart meter to identify which appliances have a consistent usage. I set it to show consumption through the day.
Retiring to bed each night at about 11.30pm, the meter shows an average of 10-11Kw usage through the day depending on whether my dear wife has baked bread or whether she has sneaked in a half hour tumble dry! before retiring, I turn off everything except for a fridge, a freezer, a 9w security bulb and 2 phone chargers.
Every morning at 8am the Smart meter shows 1.15Kw usage for the day so far. Although somewhat surprised by the amount, I first put this down to the fridge and freezer. I then plugged the fridge and freezer into my solar system overnight instead of the mains. Next morning at 8am the smart meter showed 0.85Kw suggesting that the fridge and freezer use 0.3Kw overnight - more realistic I suggest.
But what is using the other 0.85Kw over an 8 hour period? That's over 900KW per year!
In an effort to get to the bottom of it, I stayed up until midnight last night and watched the smart meter as midnight passed. The meter zeroed at midnight. Then at 3 mins past midnight, 50w appeared! I continued to watch but there was no more " usage" until I gave up at 00.12am.
Without staying up all night, I cannot fathom where the usage is coming from in such an inconsistent manner. What has used 50w in 3 minutes immediately after midnight and then accumulates another 800w over the next 8 hours? That is the equivalent of a 100w bulb on for 8 hours - surely I would notice something like this on in the house?!
Am I missing something?

 

[SPECIAL LOCATION]

How much power does your internet router consume?
How much power does the in-house-display that you have photo'd consume?
Do you have any security alarm / CCTV cameras?
Are there any outdoor lights with automatic PIR sensors? As these will consume some power whilst monitoring the detection zone to see if they need to turn the actual light itself on!
etc.. etc.. etc..

3 or 4 small items each drawing anything around quarter to half an amp could soon give you 100watts.

Power = Volts x Current.
3x items each using 0.25amps = 0.75amps
0.75amps x 230volts = 172.5watts!

Or your 50watts / 230v = 0.22amps approx..
Not a massive amount of current being consumed.

 

[Murdoch]

What is your total consumption in kwh per year?

What is your "independent" PV system power being used for?

 

[stevemul]

What is your total consumption in kwh per year?

What is your "independent" PV system power being used for?

About 3600kWh per year.
My PV charges a 100ah Lithium battery connected to a 3000/6000w Inverter to a 13 amp extension lead to my utility room.

 

[ProDave]

You would do a lot better with a low power PV system having a grid tie inverter and using the power to offset grid usage. And to help that, shift the usage of your big loads like washing machine etc to close to mid day.

Battery storage imho only becomes viable when you have more power generated than you can sensibly use in real time.

 

[stevemul]

You would do a lot better with a low power PV system having a grid tie inverter and using the power to offset grid usage. And to help that, shift the usage of your big loads like washing machine etc to close to mid day.

Battery storage imho only becomes viable when you have more power generated than you can sensibly use in real time.

My issue has nothing to do with my PV system. I only included reference to it to illustrate how I identified the issue with the Smart meter which appears to add phantom watts!
My small PV system is not intended to replace or even significantly subsidise my usage from the grid but it allows me to have a back up and learn about electric use in the home to better understand how the Utility Companies are ripping us off.
Why does 50w usage suddenly appear 3 mins into the new day when only milli amp usage is actually being used? If this is multiplied over millions of customers, it is significant false income for them.

 

[Murdoch]

^^ how are you confirming the milliamps load and the 50w usage ?

 

[stevemul]

^^ how are you confirming the milliamps load and the 50w usage ?

The 50w is showing on the Smart meter and the load(s) are from 5v transformers on the phone chargers and router

 

[Murdoch]

A smart meter uses power

 

[SPECIAL LOCATION]

The 50w is showing on the Smart meter and the load(s) are from 5v transformers on the phone chargers and router

Transformers adjust voltages and currents..
Excluding a few natural transformer losses.. (no machine or device is 100% efficient).

They do NOT generate power, consume power or change power rating..
i.e. 'power out' is just a bit less than 'power in'.

Back to my earlier post #2

50watts = approx 0.22amps..
Just under a quarter of an amp...

what are the actual ratings of your routers chargers etc...?

e.g. if you have a couple of PSU's that are 500ma / 300ma
which are 0.5amp or 0.3amps..

They are both more than 220ma (AKA 0.22amps)
e.g.
1x 500ma PSU and 1x 300ma PSU will be 800ma or 0.8amps or 184watts..
It sounds to me like your calculations are not accurate?

Why does 50w usage suddenly appear 3 mins into the new day when only milli amp usage is actually being used? If this is multiplied over millions of customers, it is significant false income for them.

50 watts IS miliamp usage!!!!!!!!!!!!!!!!!!
Why do you think 50watts is more than an Amp?

e.g. Power = Volts x Current...
so Current = Power / Volts

Power 50watts
Volts 230
50/230 = 0.217... AKA 217 miliamps!!!!!!

If we were talking of Amps used 1amp x 230volts = 230watts .... NOT 50watts..


How are you arriving at your calculation???

 

[stevemul]

Transformers adjust voltages and currents..
Excluding a few natural transformer losses.. (no machine or device is 100% efficient).

They do NOT generate power, consume power or change power rating..
i.e. 'power out' is just a bit less than 'power in'.

Back to my earlier post #2

50watts = approx 0.22amps..
Just under a quarter of an amp...

what are the actual ratings of your routers chargers etc...?

e.g. if you have a couple of PSU's that are 500ma / 300ma
which are 0.5amp or 0.3amps..

They are both more than 220ma (AKA 0.22amps)
e.g.
1x 500ma PSU and 1x 300ma PSU will be 800ma or 0.8amps or 184watts..
It sounds to me like your calculations are not accurate?



50 watts IS miliamp usage!!!!!!!!!!!!!!!!!!
Why do you think 50watts is more than an Amp?

e.g. Power = Volts x Current...
so Current = Power / Volts

Power 50watts
Volts 230
50/230 = 0.217... AKA 217 miliamps!!!!!!

If we were talking of Amps used 1amp x 230volts = 230watts .... NOT 50watts..


How are you arriving at your calculation???

My smart meter shows Watts, I’m charged in Watts /KW usage, my appliances are rated in Watts. Small appliances such as phone chargers have very little Watt usage. Certainly not 50w in 3 minutes ( ie 1kW per hour)) I cannot see the relevance of amps in this. My calculations are not meant to be “accurate” in the sense that there appears to be usage in Watts which I cannot relate to appliances in the house.

 

[ProDave]

Are you looking at the display actually on the smart meter? or are you looking at the display on the "in home display" unit?

Hint, lots of people seem to say what is shown on the IHD is a work of fiction.

 

[bladerunnerpv]

Puzzling, just some suggestions to add to the mix...
Does it happen the same time every day?
Something like a TV recorder on a timer setting ?
Computer set to optimise the hard drive space every might?
A printer doing a calibration cycle periodically?
Kids watching TV / gaming?
What's the granularity of the meter, is 50W the smallest increment it can do ?
as per post #2 anything automatically running overnight?

 

[SPECIAL LOCATION]

My smart meter shows Watts, I’m charged in Watts /KW usage, my appliances are rated in Watts. Small appliances such as phone chargers have very little Watt usage. Certainly not 50w in 3 minutes ( ie 1kW per hour)) I cannot see the relevance of amps in this. My calculations are not meant to be “accurate” in the sense that there appears to be usage in Watts which I cannot relate to appliances in the house.

Yes your appliances may be rated in Watts...
BUT the watts are calculated by the amount of current (Amps) that they draw!!!

Watts is NOT a separate independent method of measuring electricity..
As per my previous posts : "Watts = Volts x Amps"

Your meter measures the amount of electrical current (amps) flowing..
And the voltage (which can fluctuate anywhere 216v up to 253v).
So that it can calculate the Watts..

The amps are relevant if you are trying to work out what power you are consuming!

If you don't understand this, and you say you are not trying to be accurate..
I'm not sure you will resolve your questions?

 

[UNG]

The RF connections between devices like this generally are not transmitting data continuously and updating in real time, normally they transmit and update after a preset time or period has elapsed or there has been a set level of data change. So the only reliable way to monitor what is happening is at the actual smart meter itself

 

[SPECIAL LOCATION]

So.... I've been pondering this a bit more today.. and thought I would do a basic experiment to see what sort of current (& thus Watts) are typically being used at our house late at night when we are all in bed!!

Step 1...
Stick my random selection of clamp meters around the tails between cut-out & electric meter to get a rough idea of consumption on a Saturday November afternoon with only me in the house.. a few lights & computers on but not a fat lot else except all the background 24/7 running stuff..

As I do not have any form of cheap easy to use Watt-Meter.. I can only reference the current readings, (in Amps), with my various budget price level, (and accuracy), clamp meters..
Initial test we can see 2.44amps, 2.31amps and 2.2amps as the possible readings..?

Which in this case the middle meter is actually the average value of the three readings.
So at a nominal 230v I guess at that time I am consuming around 530watts.



Step 2...
Use the Blue meter, (which had the lowest reading but can measure milliamps),
to read current on individual circuits with everything else off..
i.e. Clamp meter around CU tail turn off ALL MCBS so shows Zero current.
Then switch on individual circuits and note down current reading...

{It is quite easy to isolate individual loads as we have 20 final circuits some dedicated to specific purpose.. e.g. There are 7 socket circuits; Downstairs, Upstairs, Kitchen, Hall, Garage, Loft, Caravan outdoor... (p.s. only one is a 32A ring)}

My readings were as follows:-
Cooker, (electric double oven), only running the clock/timer:
7.8mA or 0.0078amps or 1.8watts @ 230v nominal.

Security intruder alarm:
63mA or 0.063amps or 14.5watts @ 230v nominal

4x mains powered interlinked smoke detectors:
173mA or 0.173amps or 39.8watts @ 230v nominal

Traditional doorbell transformer:
20mA or 0.02amps or 4.6watts @ 230v nominal

Loft socket, 1x traditional 8port Co-Ax TV distributor & mast-head amplifier supply:
10mA or 0.01amps or 2.3watts @ 230v nominal

Kitchen Sockets with ONLY combined American style fridge/freeze plugged in:
135mA or 0.135amps or 31.1watts @ 230v nominal
{but did jump up-to 722mA or 0.722amps or 166.1watts when first switched on!!}

So the combined "scores-on-the-doors" so far are:-
1.8+14.5+39.8+4.6+2.3+31.1 = 94watts!!

even allowing for percentage inaccuracies of the test meters..
and/or of using 230v nominal..
we are still looking at over 50watts!!

And other bits I haven't yet included...

Hall socket; Internet router, cordless telephone charging base including answerphone, and smart LED table lamps connected via wifi to Alexa:
69mA or 0.069amps or 15.9watts @ 230v nominal.

Central heating boiler while pump is running:
191mA or 0.191amps or 43.9watts @ 230v nominal

So...
My conclusion is that even late at night anything from 50watts to 100watts+ could be easily consumed by various 24/7 appliances..?

 

[Bob Minchin]

Virtually every device you list is a non resistive load and so ohms law calculations cannot be used to work out the power consumed. The power factor has to be born in mind.

 

[stevemul]

So.... I've been pondering this a bit more today.. and thought I would do a basic experiment to see what sort of current (& thus Watts) are typically being used at our house late at night when we are all in bed!!

Step 1...
Stick my random selection of clamp meters around the tails between cut-out & electric meter to get a rough idea of consumption on a Saturday November afternoon with only me in the house.. a few lights & computers on but not a fat lot else except all the background 24/7 running stuff..

As I do not have any form of cheap easy to use Watt-Meter.. I can only reference the current readings, (in Amps), with my various budget price level, (and accuracy), clamp meters..
Initial test we can see 2.44amps, 2.31amps and 2.2amps as the possible readings..?

Which in this case the middle meter is actually the average value of the three readings.
So at a nominal 230v I guess at that time I am consuming around 530watts.

View attachment 16296

Step 2...
Use the Blue meter, (which had the lowest reading but can measure milliamps),
to read current on individual circuits with everything else off..
i.e. Clamp meter around CU tail turn off ALL MCBS so shows Zero current.
Then switch on individual circuits and note down current reading...

{It is quite easy to isolate individual loads as we have 20 final circuits some dedicated to specific purpose.. e.g. There are 7 socket circuits; Downstairs, Upstairs, Kitchen, Hall, Garage, Loft, Caravan outdoor... (p.s. only one is a 32A ring)}

My readings were as follows:-
Cooker, (electric double oven), only running the clock/timer:
7.8mA or 0.0078amps or 1.8watts @ 230v nominal.

Security intruder alarm:
63mA or 0.063amps or 14.5watts @ 230v nominal

4x mains powered interlinked smoke detectors:
173mA or 0.173amps or 39.8watts @ 230v nominal

Traditional doorbell transformer:
20mA or 0.02amps or 4.6watts @ 230v nominal

Loft socket, 1x traditional 8port Co-Ax TV distributor & mast-head amplifier supply:
10mA or 0.01amps or 2.3watts @ 230v nominal

Kitchen Sockets with ONLY combined American style fridge/freeze plugged in:
135mA or 0.135amps or 31.1watts @ 230v nominal
{but did jump up-to 722mA or 0.722amps or 166.1watts when first switched on!!}

So the combined "scores-on-the-doors" so far are:-
1.8+14.5+39.8+4.6+2.3+31.1 = 94watts!!

even allowing for percentage inaccuracies of the test meters..
and/or of using 230v nominal..
we are still looking at over 50watts!!

And other bits I haven't yet included...

Hall socket; Internet router, cordless telephone charging base including answerphone, and smart LED table lamps connected via wifi to Alexa:
69mA or 0.069amps or 15.9watts @ 230v nominal.

Central heating boiler while pump is running:
191mA or 0.191amps or 43.9watts @ 230v nominal

So...
My conclusion is that even late at night anything from 50watts to 100watts+ could be easily consumed by various 24/7 appliances..?

That is very interesting, thank you. It confirms exactly my point and situation.
Last night, after being out all the sunny day, I had a full battery of "free" solar electricity so I confidently connected the fridge freezer and the separate freezer to my solar battery, thus isolating them from the mains.
That left only 3 phone chargers, the house alarm, one security camera. I set the CH thermostat to 15 degrees so no CH pump use.
This morning at 8am my Smart Meter showed 700w usage since midnight!
Based on your figures, allowing for 100w of usage by the items we list, that is 600w of phantom use. That's 1.8kW over 24 hours, 657kW per year at my tariff of 27p per kW plus VAT = £186!
The next few nights I am going to isolate each circuit on the consumer unit in turn to try to identify the rogue item.

 

[stevemul]

The RF connections between devices like this generally are not transmitting data continuously and updating in real time, normally they transmit and update after a preset time or period has elapsed or there has been a set level of data change. So the only reliable way to monitor what is happening is at the actual smart meter itself

My Smart Meter shows usage in real time. If I boil a kettle, the usage shows immediately on the meter.

 

[Murdoch]

in my experience people have far more small items drawing power than they imagine!