Electricity Usage & Solar Feed-In (query)

CoreyR
Conductor
4 Replies 3543 Views

Hello, I have a query about my current AGL electricity bill & how the smart meter interacts with by inverter & lithium battery.

Monday 03 April 2023.jpg

I have new solar panels & 9.6 KW lithium battery installed in December 2022 and the quarterly electricity bill Jan 04 to April 03 has arrived. The bill was not what I was expecting and looking through the AGL usage meter website https://myaccount.agl.com.au/usage,  I have found hundreds of anomalies that I can’t explain throughout the 90-day billing period.

 

I have found that for EVERY day of the billing period there has been at least one occurrence, most days 2, 3, 4 or 5, where AGL has purchased electricity from my battery and immediately replaced it from the grid with the exact KWh.

In the vast majority of cases this occurs during the night when there is obviously no activity from the solar panels, so electricity is being drawn and sold from my battery storage. On the rare occasions where it occurs during daytime hours, its during heavily overcast days where I would be using my battery.

My battery has been below 10 % charge for a handful of days and for 70 of the 90 days, the battery would never have gone below 40% charge.

The attached screenshot shows my usage according to https://myaccount.agl.com.au/usage  for a single day, Monday 03 April 2023, where at,

→ 12am : 0.71 KWh was sold to the grid AND 0.70 KWh purchased from the grid

→ 4am : 0.28 KWh was sold to the grid AND 0.28 KWh purchased from the grid

→ 5am : 0.65 KWh was sold to the grid AND 0.64 KWh purchased from the grid

→ 10pm : 0.95 KWh was sold to the grid AND 0.95 KWh purchased from the grid

 

This happens EVERY day, day after day after day, and it adds up and accounts for 90% of the electricity my bill says I have purchased.

 

My smart meter has tallied these quantities over each day of the billing period and have included them all as usage from the grid when I suspect they should be usage from my battery. I have gone through every daily chart of the 90-day billing period from the https://myaccount.agl.com.au/usage  site and removed all the offending instances where equal or very near equal quantities of electricity are sold & purchased at the same time and come up with about 18KWh of electricity purchased over the quarter.

Also, I also have a third-party app that monitors usage from my solar inverter, including daily KWh of household load, self-consumption from solar panels, Battery charging from solar panels, battery usage, export to grid and import from the grid. The amount purchased from the grid for the year to April is 15.8 kWh (or about 0.17 KWh per day on average) which corresponds with the above adjustments.

I get the impression that the smart meter is registering electricity being drawn from my battery as electricity being drawn from the grid, and if that is the case, I am paying for electricity from my lithium battery.

My question is (depending on if it was Buy then Sell OR Sell then Buy)

  • Why would I need to purchase electricity from the grid if I just sold the exact amount to the grid (+why would I be selling electricity to the grid from my battery in the middle of the night?)

OR

  • Why would I need to sell electricity to the grid if I just purchased the exact amount from the grid. (+In this scenario the grid is charging my battery in the middle of the night then taking it back -but my battery is very rarely below 30% charge)

 

I am not talking about huge dollars more of the principal that approximately 90% of the electricity purchases from the grid in my bill may be in error and that I might be paying to use electricity stored my own lithium battery.

I was wondering if anyone out there has ever seen or had a similar experience such as this?

I have contacted the AGL help chat & they had said they will investigate it but have not got back to me yet. My bill is due in a few days.

Thanks.

7 REPLIES 7
-Olgi-
AGL Moderator
0 Replies 3524 Views

Hi @CoreyR,

 

Welcome to AGL Neighbourhood!

 

I'll sent you a private message to grab your account information from you, so that I can have a look at your meter interval data and to help you further.

 

Kind Regards,

-Olgi-

Hendra
Switched-on
1 Reply 3496 Views

Hi Coreyr

Just wondering if you could share what was ultimately resolved in your case. Not the $ refunds; about how in principle this issue was resolved. Also, could I request you to share links to different Apps that you mentioned in your post. I am a first time Solar Piwer user. Would like to check the billing the way you did.

Thanks for your detailed and educative post, Tegards

John-T
Powerhouse
0 Replies 3480 Views

@CoreyR 

 

Hi Cory I hope things are getting sorted for you.

 

Likewise I would also like the name of that 3rd party app it sounds extremely handy.

 

Regards

John

CoreyR
Conductor
2 Replies 3471 Views

Hi Hendra & John-T

I'm still waiting on an outcome but in regard to your question, my solar inverter (sungrow residential hybrid single phase inverter) monitors and collects all power generation data, battery use and grid interaction data and is available over wifi connection via login & password that was created when the inverter was installed. The inverter has a build in wifi adapter that allows to to access data from PC or phone. I believe the app is designed specifically for the Sungrow devices but its called 'iSolarCloud'

 

Similar applications should be available for the equipment you end up getting, but your solar contractors would be the best source of information on most suitable app for your setup.

 

Cheers

Corey

 

Examples of data available on the app once setup & connected are below

 

iCloudSolar (live data) -I think it has a 30 second lag time bit essentially 'Now'

iCloudSolar -Live Data (Now)iCloudSolar -Live Data (Now)

shows what is going by moving arrows where and how much + live battery charge %

 

 

iCloudSolar (daily summary -per hour)

iCloudSolar -Daily Summary (per hour)iCloudSolar -Daily Summary (per hour)

 

 

 

iCloudSolar (monthly summary -per day)

iCloudSolar -Monthly Summary (per day)iCloudSolar -Monthly Summary (per day)

 

iCloudSolar (year to date summary -per month)

iCloudSolar -Year to Date Summary (per month)iCloudSolar -Year to Date Summary (per month)

 

 

John-T
Powerhouse
0 Replies 3468 Views

Thanks for that Cory,

 

I have the Fronius App for my Fronius Symo Solar Inverter, I mistakenly thought you had an all in one app that was compatible with most inverters. 👍 

 

Kind Regards

John

Hendra
Switched-on
0 Replies 3465 Views
Thanks CoryR
CoreyR
Conductor
0 Replies 2659 Views

This issue has been resolved. For anyone interested it finally came to light that my electric hot water system was on off-peak which sounds reasonable but as the solar inverter has no connection to the off-peak circuit on the smart meter, the electric hot water heater was by-passing the solar system entirely and getting all its electricity from the grid. The inverter could not comprehend the unknown incoming electricity from the grid and (apparently) to compensate was dumping (selling) the same quantity back to the grid from the battery.

 

With the hot water connection corrected to run through the solar inverter, my daily electricity purchases from the grid (according now to AGL) has averaged 0.14KW for the past 19 days which is in complete alignment with iSolarCloud. I have been in credit for every day since the correction and it is now looking like AGL will be paying me about $10 per month going forward.