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How much power do you use from the grid, on average, throughout the darker days of the year?

  • 17 January 2020
  • 10 replies
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Newbie here, hello everyone!
I have a problem / query / concern!

We had solar panels and two batteries installed in March 2019.
On 22nd November, we had Smart Meters installed for electricity & gas. 
Since then, our electricity usage has rocketed and I do not believe it’s a coincidence. 

Usage:
Apr: 22kWh
May: 35kWh
June: -59kWh
July: 5kWh
Aug: 9kWh
Sept: 40kWh
Oct: 17kWh
Nov: 47kWh
Dec: 104kWh
Jan: 305kWh

The last few months in detail:
Oct to Nov =  47 kWh (clocks go back)
3rd Nov to 22nd Nov = -(minus)2 kWh!!
22nd Nov to 3rd Dec = 106 kWh!! (smart meter installed on 22nd)
4th Dec to 3rd Jan = 305 kWh!! 

I appreciate you will use more electricity in the winter but this seems suspiciously high. 

I have tweeted OVO and done the creep test as recommended; I didn’t find any issues.
We haven’t had any new appliances and our daily routine has not changed.
I have contacted our PV installer and they will be coming round to check everything.

Can anyone provide an insight as to how much power they use from the grid, on average, throughout the darker days of the year?

Help appreciated,
Matt  

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Best answer by PeterR1947 21 January 2020, 17:48

These are my usage figures for the same period that you quote, I am an EV driver so have subtracted the usage that was for chargng the car.  I also have a 2.82kWh PV system

Apr 216

May 207

Jun 201

July 75 (good generation month)

Aug 228

Sept 193

Oct 154

Nov 163

Dec 266

Your figures pre-smart meters look a bit unrealistic, unless you have a massive PV system; mine is 2.82kWh and I tend to use between 10 to 15 kWh per day without charging the car and without too much PV generation, however, I don’t have a battery.  Do you charge the batteries on an E7 rate at night then use the batteries during the day?

Are you able to split usage, for example usage by month together with total PV generated, that data on PV would help as would any data of how much you had put into the batteries.

Average UK domestic usage figures per annum are here:

  • Low consumption is estimated as being between 1,900kWh and 2,500kWh
  • Medium consumption at 3,100kWh to 4,200kWh
  • High consumption is between 4,600kWh and 7,100kWh.

My PV system generates between 2000 and 2500kWh per annum.

Hope all this gives you food for thought!

Just thought of something to try, on a good solar day does your IHD show negative consumption?

Peter

 

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Userlevel 5

Welcome to the forum, @Matt1985, I’ve changed the title and added a few tags to make this easier for other users to find.

 

@Transparent, @PeterR1947, do you have any suggestions on what may be happening here? :) 

Userlevel 6
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These are my usage figures for the same period that you quote, I am an EV driver so have subtracted the usage that was for chargng the car.  I also have a 2.82kWh PV system

Apr 216

May 207

Jun 201

July 75 (good generation month)

Aug 228

Sept 193

Oct 154

Nov 163

Dec 266

Your figures pre-smart meters look a bit unrealistic, unless you have a massive PV system; mine is 2.82kWh and I tend to use between 10 to 15 kWh per day without charging the car and without too much PV generation, however, I don’t have a battery.  Do you charge the batteries on an E7 rate at night then use the batteries during the day?

Are you able to split usage, for example usage by month together with total PV generated, that data on PV would help as would any data of how much you had put into the batteries.

Average UK domestic usage figures per annum are here:

  • Low consumption is estimated as being between 1,900kWh and 2,500kWh
  • Medium consumption at 3,100kWh to 4,200kWh
  • High consumption is between 4,600kWh and 7,100kWh.

My PV system generates between 2000 and 2500kWh per annum.

Hope all this gives you food for thought!

Just thought of something to try, on a good solar day does your IHD show negative consumption?

Peter

 

Thank you for you response Peter.
 

Your figures pre-smart meters look a bit unrealistic, unless you have a massive PV system; mine is 2.82kWh and I tend to use between 10 to 15 kWh per day without charging the car and without too much PV generation, however, I don’t have a battery.  Do you charge the batteries on an E7 rate at night then use the batteries during the day?
​​​

I have a 3.60kWp PV system.  No, we are not on E7.

The batteries charge during the day with a percentage of the generation going to the batteries - 2x 2kW.

An example - at 3.05pm on a cloudy, dull afternoon…
104w being generated. 
115w from the grid.
5.19w to the batteries.
222w house consumption. 

I’m struggling to obtain usage data prior to the Smart Meter being installed, waiting to see what OVO come back with. The SolarMan app I have for the PV system isn’t the best either!

Generation (kWh)
Apr: 331.10
May: 425.40
June: 368.70
July: 429
Aug: 2.41 MWh (something went terribly wrong on 28/08 spiking at 2.0MWh)
Sep: 338.70
Oct: 187.70
Nov: 61
Dec: 62.50

Let’s take Monday 20/01/20. A fairly sunny day. My wife had an operation this day so we were out the house the majority of the day. 
Generation was 6.10kWh
My OVO usage was 7.3kWh

Spike points:
6:30 - 8:30am = 4.72kWh
1:00pm = 0.68kWh
15:00 = 0.53kWh

Rest of the day 0.01kWh - 0.03kWh

Yet on 21/01/20… We were in all day, TV on more than usual etc. I was on carers leave!
Generation was 5.80kWh
My OVO usage was 1.1kWh

Spike points: 
6:30 - 8:30am = 0.38kWh
6pm = 0.05kWh

Rest of day 0.01kWh - 0.02kWh

At the moment, none of it is making much sense. 
 

Userlevel 6
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Matt, you didn’t answer my question “ Just thought of something to try, on a good solar day does your IHD show negative consumption? “

Sorry Peter. The IHD only goes back a week and there has been no negative during that time. It is not something I have noticed since we had it installed.

Userlevel 6
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Matt, the reason for the question is to check if something in your set up thinks generation is usage so the meter records it as such;  obvioulsy if your IHD shows exporting then that isn’t happening.  You don’t need a terribly sunny day for exporting to happen, you could always turn off a few MCBs (but not the one that feeds your PV inverter!) to reduce the house usage to force it to export.

Peter

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No PV, No batteries. Detached house (1980s) with four adults (alleged) : monthly consumption fairly flat across the year at approx 9kWh per day pre EV, 19kWh per day post EV. These figures are below the national averages.  Relatively flat instead of seasonal as our lighting is all low energy and the tumble dryer is reserved for emergencies.

OVO predict 660kWh consumption for a typical 4 bed detached during December.

 

 

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Standout data point has to be the 2.0MWh  for one day in August (28th).  That is incorrect by more than one order of magnitude.

Was your actual August bill indicating enormous figures too or is this an example of incorrect display of consumption rather than incorrect billing

Standout data point has to be the 2.0MWh  for one day in August (28th).  That is incorrect by more than one order of magnitude.

Was your actual August bill indicating enormous figures too or is this an example of incorrect display of consumption rather than incorrect billing

I was simply stating the generation since the PV was installed. No idea why there was a surge but something obviously went wrong on that day as the generation for the rest of the month was what you would expect. The bill for August was fine.

PV Installer has a hunch that the system has not been connected to the meter properly. Hopefully be round towards the end of the week to check. My hunch is I’m being charged for the electricity I’m generating / exporting / using from batteries or similar! 

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PV Installer has a hunch that the system has not been connected to the meter properly. Hopefully be round towards the end of the week to check. My hunch is I’m being charged for the electricity I’m generating / exporting / using from batteries or similar! 

That was my thought too and why I asked you to check the IHD for exporting.

Peter

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