Discrepancy between solar inverter power generation and the AGL app

[Kevinh99]

Hi There, I've been monitoring my 5kw Fronius inverter and the kwh produced each day. July 26th was an ok day and reading via the Fronius solarweb app was 18.0kwh produced. Yet on the AGL App for the same day it states just 7.22kwh sold to the grid and 21.01kwh bought from the grid. The figures don't stack up. 

Thanks

Kevin

[jayden_AGL · Accepted solution]

Hi Kevinh99,

Welcome to the AGL Community!

As you've mentioned, your inverter records the amount of power your system generates, whereas your meter records the power you export to grid. Based on the figures you've provided, If your system generated 18kWh and exported 7.22kWh, the difference of 10.78kWh would've been used within your property during daylight hours. The 21.01kWh imported from the grid would've been used during non-daylight times, or during the day when your system was unable supply enough power to meet the demand within your property.

Kind regards,

Jayden

[Kim1]

I have long read my meters twice a day (morning and at sundown) and find there is a difference of 3 to 4 k/watts  from what my panels produce to what my smart meter tells me I have exported. I have put this down to the fridge running and occasional power I use during the day. This backed up by energy I import during the day at best 0.4 k/w and if I or my wife does cooking during the day up to 8k/w during the day, overnight we can use at best 5 k/w if all the cooking is done before sundown and have an early night. Hence with using power from the panels and overnight usage with minimal power usage would be about 5 k/w day or night. Of this is rare as we mostly cook after sundown. I find the ducted air con the biggest user of power and hence it is rarely used (heating or cooling) I got the ducted system as a deal with the new house but regret that now and should have gone for individual room a/c units.

To get back to the question at hand I still check with the AGL site what the readings are and they are never the same as my readings from the meter (only out by 1 or 2 k/w), now this is a smart meter it should read the same as the AGL meters I can only put it down to when the meter is read but if it is after sundown (which it should be to get the full solar reading) then why the difference. AGL cover themselves by stating their reading are estimates ( or as their put only indicative of the true reading) and I will find out when the bill comes in.

Sorry for being so long winded.

[NeilC]

Kim,

I am fairly new to AGL and in fact have just completed my first billing cycle with AGL and 16 days into my 2nd.

Now I was very disappointed that my bill was FOUR cents out from what I calculated.

I have a spreadsheet that I fill out daily using the CSV supplied by either my Electricity Supplier or the horrible AGL csv file.

AGL do not supply in NEM format but SA Power Networks supplies the data in NEM format but do not always get the correct data. So I have to add offsets into my programme to allow for missing days.

Not a problem as long I read my Meters at 23:30 to get the true Values then compare my reading to the reading produced up to the my meter read date.

I have written a programme that converts the AGL csv file into NEM format.

Also written a programme that converts NEM format files into something completely usable.

Date	Peak	Exported	Solar Gen	Used	Meter	Solar
Carried Fwd	0	0	1579.9		1038.348	3209.208
1-Aug	2.963	6.721	9.4	2.68	1041.311	3215.929
2-Aug	4.130	9.022	13.0	3.98	1045.441	3224.951
3-Aug	4.562	5.379	9.2	3.82	1050.003	3230.330
4-Aug	6.697	19.008	24.4	5.39	1056.700	3249.338
5-Aug	6.357	21.81	26.3	4.49	1063.057	3271.148
6-Aug	4.315	15.266	19.4	4.13	1067.372	3286.414
7-Aug	5.248	6.313	9.7	3.39	1072.620	3292.727
8-Aug	5.411	6.212	10.9	4.69	1078.031	3298.939
9-Aug	6.692	14.869	19.8	4.93	1084.723	3313.808
10-Aug	4.678	13.409	19.6	6.19	1089.401	3327.217
11-Aug	6.008	14.233	20.7	6.47	1095.409	3341.450
12-Aug	4.811	12.122	15.9	3.78	1100.220	3353.572
13-Aug	3.802	20.731	24.5	3.77	1104.022	3374.303
14-Aug	3.516	25.882	29.5	3.62	1107.538	3400.185
15-Aug	4.025	16.223	19.5	3.28	1111.563	3416.408
16-Aug	4.479	9.905	15.2	5.30	1116.042	3426.313

Above is the sheet that I use to keep track of my usage and my ACTUAL POWER METER from the data supplied by AGL and my solar inverter. The used column is what I have used of the SOLAR generated for the day.

I do not have anything that uses Controlled Load or Off peak so do not have that in my sheet.

Do you have electric hot water, is that using your power.

We have a heat pump and set that to run from 11:00 to 17:00 each day (thus using Solar).

That uses about 3kw of our average daily consumption of 4.8 used from our solar output.

As I have said I am 16 days into our next bill.

Meter Readings
Peak Meter	Off Peak	Solar	DATE
1038.348	0	3209.208	31-Jul-19
1077.953		3298.939	8-Aug-19
1116.137		3426.318	16-Aug-19
Used	Used	Produced	Days
77.789	0.00	217.110	16
Averages Per Day
4.86	0	13.57
Cost Per Day	$            0.22

I won't go into great details but the COST PER DAY is inclusive of all electricity used by our house and includes our supply charge.

We are still getting overcast days here and rain (Adelaide SA).

We pay including GST 41.58 cents per KW and 91.3 cents per day for Supply Charges, 20 cents per Kw for Solar generated. If my average  Solar / used is greater than 3.00 then I do not pay a bill.

At the moment it is 2.792 which equates to 21 cents (3- 2.792)*100.

To go further at my current use and supply averaged out to when my next bill is due. My bill will be

Bill Due 29/10/2019
Current Bill
No Discount (Estimate)
Supply	$           74.70
Peak	$         165.40
Total	$         240.10
+GST	$           24.01
	$          264.11
Solar Feed in	$         244.25
Total Payable	$         19.86
Payment Required Per Fortnight Pay on Time	$             4.00
Credit	$            71.05
Cost Per Day	$              0.22
DUE DATE	29/10/2019

Here is a CSV sample of what my programme produces in regard to the CSV file supplied by AGL (then converted to nem format) and then run through my MeterRead programme.

NMI 20013969096   <-->   Meter #U260000657   <-->   NMI ID=E1   Interval Mins=30

DATE	NMI	TYPE	D/Total	00:00>07:00	07:30>18:00	18:30>23:00	23:30>00:00
20190801	E1	General	2.963	1.467	0.399	1.02	0.077
20190802	E1	General	4.13	1.245	0.8	1.953	0.132
20190803	E1	General	4.562	2.088	0.812	1.484	0.178
20190804	E1	General	6.697	2.18	1.045	3.355	0.117
20190805	E1	General	6.357	2.554	2.052	1.645	0.106
20190806	E1	General	4.315	1.743	0.748	1.73	0.094
20190807	E1	General	5.248	2.043	1.504	1.641	0.06
20190808	E1	General	5.411	1.75	1.845	1.685	0.131
20190809	E1	General	6.692	2.17	0.948	3.306	0.268
20190810	E1	General	4.678	1.594	1.433	1.508	0.143
20190811	E1	General	6.008	2.204	2.172	1.453	0.179
20190812	E1	General	4.811	2.339	0.792	1.558	0.122
20190813	E1	General	3.802	1.712	0.226	1.739	0.125
20190814	E1	General	3.516	2.173	0.343	0.881	0.119
20190815	E1	General	4.025	1.335	0.411	2.106	0.173
20190816	E1	General	4.479	2.359	0.624	1.496	0
Total:	E1	General	77.694	30.956	16.154	28.56	2.024
DATE	TYPE	NMI	Last Data	Meter Read	Day Avg
20190816	Solar	B1	9.905	3441.182	12.771
20190816	General	E1	4.479	1122.734	4.57
20190816	Controlled	E2	0	0	0

As you can see I can manipulate the data any way I like

DATE

NMI

TYPE

D/Total

Are default settings

I then can add up to 10  additional queries for any times that I want to add using a configuration file

You can see at a glance that we are having cloudy days due to the high usage between 7am and 6pm

Electronic meters are "read" at midnight but using nem file and a bit spread sheet know how. You can take a meter reading anytime (well at the hour or half past) and going from you last meter read (from your bill)  add up all the daily usages plus the part day up to when you read your meters confirm you meter reading.

Solar is easy, if your are not producing power then the meter is correct for that night (after sunset) or if before dawn then the night before.

If you know what you are doing you can check your SMART meter to see how many amps you are using and how many amps you are putting back into the grid..

Simply multiply the amps by 250 to get the watts (close approximation). If you are putting 20 amps into the grid (20*250=5000 watts or 5Kw) then you are producing the maximum out from your solar system.

Yes you may have a 6.6Kw system but your inverter is limited to 5Kw (and will reduce further on hot days)

Hope this helps but I have been using a smart meter and my programmes for some time and the only fault I have found is that our meter runs on Vic time not SA time.....

Hence my 4 cents wrong on my bill average usage between 23:30 and 00:00 is 0.1265 watts at the moment so unless I change my programme to run on VIC time it will be 5 cents out this time.

Cheers

Neil

[Kim1]

Thanks Neil for such an in-depth analysis and far more accurate recording and spreadsheet setup than I am capable of. I am happy with what I record and my simple spreadsheet is set up to tell me how much I make per day and how much I use per day and the difference. Here in Queensland I haven't been able to find a program on the AGL website to record these and I don't think I am capable enough to convert it from cvs to nem format (even if I knew what they were). I have tried to add up the cost from the information I have gathered and I would be happy if I could come as close as 4 cents difference.

Simply put as long as I make more solar power than I use then I am happy. The true test will be if I can work out when the next bill comes if I come any where near what AGL has calculated. Having said I want to make more than I use, this might change during the summer months when using the a/c will be a necessity due to Queensland hot/ humid weather. At present we have homestay students and providing them with comfortable conditions for their studies is a priority. If it was myself and my wife I would take advantage of shopping centres and libraries using their a/c.

I do have solar hot water and I believe it has a pump to circulate the water between the tank at ground level and the roof panels but it apparently it automatically heats up when the water get below a certain temperature, 50 degrees I believe. So I am not sure what power it uses and again with students if and when it heats up, if it was just my wife and myself I don't believe it would need the boost. Here in Queensland we are blest with generally sunny days but  I believe once the temp gets above 25 degrees the panels are less effective again I am happy with what I am producing at most so far this winter the best was 22.602 k/w for my 4.3 /k/w system, I was impressed with you getting a couple of 26 k/w on a few days. I have to remain below 5 k/w system or I will lose my 52 cents feed in tariff a carry on from the old system on the house we knocked down to rebuild a new one. 

Once again Thank you for your reply it sure has enlightened me to how other systems work and in different states with their different weather zones. Keep up your recording and calculations your dedication may help others as much as it helped me. I will be interested in what your summer reading will be compared to here with mine. I would pass on some of my readings from my spread sheet if I knew how.

Kim Harley

[NeilC]

Kim,

When you log in on the page you can see your icon and settings.

Third icon on the right is E-Mail.

You can send personal messages via that.

Cheers Neil

[MrWill]

I have just recently fallen into this same trap with the smart meter. I believe it has been wired wrong, all my renewable energy is being charged as energy used and the energy my house is using is being credited as feed in energy. I just went out for 2 hours and had everything turned off, my meter said I used 4kw and I fed into the grid 0.2, I look on my inverter app and presto, the solar panels made 4kw in those 2 hours...

how do I go about getting this resolved?

[NeilC · Accepted solution]

Hey MrWill,

Who installed your Meter can you contact them, the guy that put my meter in gave me his contact details.

I would agree with you that the meter has been wired up incorrectly, can you see on the meter what the numbers of the meters are and compare what the numbers are with your meter specifications from your supplier (your supplier is not the retailer AGL).

The information is normally available on your suppliers website as to what numbers appear under the meter readings.

In SA the meters are OFFICIALLY installed by the retailer and then the Supplier supplies the power and the Retailer makes the profit. In SA we only have one supplier for ON GRID power unlike VIC where there are 7 Suppliers (Although two are now the same company I believe) I know there are a few in NSW and more than a couple in  Qld.

https://www.energymadeeasy.gov.au/hot-topics/be-meter-smart-your-rights-when-getting-smart-meter

Above is a link to a Federal site regarding smart meters (as from December 2017, your retailer is responsible for installing new and replacement meters.)

I would ring AGL ASAP and ask them what is happening and who to contact.

Failing that go to your Supplier (Contact number should be on your bill)

Next port of call after that, in Victoria is the Energy and Water Ombudsman Victoria https://www.ewov.com.au  or (phone 1800 500 509).

Hope this helps and let us all know the results

Neil

[MrWill]

So... my live data started working again once my account was un blocked, due to not being affected by bushfires.

Now i am seeing the live data, it is not matching the numbers i see from the meter. For instance, one day there the meter used about 45kw from grid and 10kw feed in, which is huge! The app data said i used 23 and fed in 12. The 2nd set of numbers is less concerning and more like what i would have used.

Now im starting to think the smart meter is displaying the actual usage as grid+solar used? 

Any information on this?

[NeilC]

Hey MrWill,

Find out how to to send me a PM (private message) and I will send you an email address and you can send me a copy of your MyDataUsage_ and I will analyse it for you.

Can't do much else to help you though I don't work for AGL and do these things to help others

Cheers

NeilC