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Mismatch in electricity imported on my solar PV app compared to my smart meter and OVO online account?

Forum|Forum|3 years ago
March 11, 2023
18 replies
2531 views

Hey,

im wondering if anyone else has had similar issues, I was advised against smart meters due to their history of being inaccurate but figured was just paranoia.

Below you can see on the 9/3/23 I was charged for 30Kw of electricity, despite only using 22kw from the grid that day (to charge my car), I notice couple days before it also has slight over spending despite again not consuming that much from the grid. I sadly only got Solar this week so this may have been going on for the past couple months too (our routines haven’t changed)

curious on anyone’s thought?

Best answer by BPLightlog

Updated on 16/05/25 by Emmanuelle_OVO:

Interested in getting solar? Good news!

The solar fed from CT’s will not be that accurate as mentioned. It also generally doesn’t record continuously but just sample every few minutes.
On your usage chart, just check that these are smart meter readings and not estimated - that can happen from time to time.
All electricity meters are calibrated and have to be within tolerance to be in service.

M.isterW

Rank 6

I assume your top picture is from your solar app? In most cases they measure the current flow from a CT clamp on your meter tail and these aren't very accurate. While it's not impossible that your smart meter is incorrect it's far more likely that your solar app is wrong.

My solar app always reads at least 10% low.

1992 4 bed detached house. Solar PV + battery, Zappi EV charger, Mitsubishi Ecodan ASHP and i-life2 fan assisted radiators.... No gas 😊

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CaolAuthor

Rank 2

Yeah that’s correct.

I guess that is possible, I also have monitoring of the car charging (16kw to the car) which would leave 14kw for the rest of the house that whole day which we use around 8-12kw a day but that’s not including that we generated 4kw so should be like 8kw so still seemed over what it should be.

BPLightlog

Solved

Super User

Updated on 16/05/25 by Emmanuelle_OVO:

Interested in getting solar? Good news!

The solar fed from CT’s will not be that accurate as mentioned. It also generally doesn’t record continuously but just sample every few minutes.
On your usage chart, just check that these are smart meter readings and not estimated - that can happen from time to time.
All electricity meters are calibrated and have to be within tolerance to be in service.

Bring me Sunshine ~ E&E {Solar PV, Battery Storage, Hybrid EV, ASHP and Home Assistant automation}

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CaolAuthor

Rank 2

Just giving an update for anyone that may still see this thread.

2 weeks on and it seems our useage from the Ovo app is pretty unchanged and on somedays even more useage than history. (Started solar from 7th March, some days seem to report correct around 1-5Kw, especailly if we were away for the weekend) but still feels the ‘smart’ meter is not recording only the electricity from the Grid

Feb:

March:

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CaolAuthor

Rank 2

Report from the Solar app:

As mentioned above some will say this is less accurate, Ovo says for March we have spent 417.46Kw but the solar app is reporting 207.26Kw bought from the grid (just under half of what Ovo says, which is quite a difference and not a minor clamp inefficiency)

BPLightlog

Super User

Do you have pictures of your meter and clamp positions @Caol ? Your export figure looks high also unless your batteries were full on those days.
You could also check any detail from the OVO feed for spikes in usage at specific times of day on the ‘high’ consumption days - for example 16th March

Bring me Sunshine ~ E&E {Solar PV, Battery Storage, Hybrid EV, ASHP and Home Assistant automation}

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CaolAuthor

Rank 2

Not to hand sadly. The high export days on the 10/11th March seem about right (we were away for the weekend)

For these dates it’s pretty comparable and what I’d expect for the +/- mismatch

Solis: 10th 3.77, 11th 1.88

OVO: 10th 4.11, 11th 1.96

BPLightlog

Super User

Do you have a feed of usage every 30 mins from your meter? If not it might be worthwhile. I was thinking more in the detail of a particular day of a mismatch and looking at what times the additional usage is occurring

Bring me Sunshine ~ E&E {Solar PV, Battery Storage, Hybrid EV, ASHP and Home Assistant automation}

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CaolAuthor

Rank 2

Yeah we have the 30min reporting form the smart meter enabled to try track whats going on.

Looking on the 13th March

Solis: 4.65 (from grid)