Net consumption not matching SDG&E

[Sparta_SC]

Hi everyone,
Switched ON my 4.56KW Solarword 285+ Enphase system in December and have the automated generation and consumption data linked to PVoutput. SDG&E NEM was enabled last month but i still don't see any change to the online energy usage page. I was hoping i could see the "received" and "delivered" energy broken down on the SDG&E page but don't see it yet? Is this available for other users?

Also, i am seeing a discrepancy on the PVO computed NET energy and what SDG&E shows me. is this due to averaging error or is there something missing in my understanding
[[Using the rainforest automation Z109-Eagle for capturing consumption]]

Here is an example (see attached snapshots)

on 1/19: per SDG&E, energy usage was: 10.59kh while from PVO, imported =10.52kWh (close to SDG&E usage ) but the system also exported 3.79KwH. Shouldn't the exported be reduced from the SDG&E usage?

[sensij]

On the page you are looking at, you have five columns: Generated, Exported, Consumption, Import, Net. These are related to each other by the following:

(Consumption - Generated) = (Import - Exported) = Net, with a positive sign meaning you are a net consumer of energy. The Net number should match what SDG&E reports. As far as I know, the received and delivered data is not accessible though any of SDG&E's online reports.

It does look like the SDG&E data you posted is reporting total Imported, and not the Net. Are you sure that your system was given Permission to Operate? SDG&E has a net metering specific department... you can call or email, their contact info is here.

As an aside, the meter captures three values that the Eagle can see: Summation Received (PVO Exported), Summation Delivered (PVO Import), and Instantaneous Demand. PVOutput's Eagle uploader is based on the changes in value of the Summation Received and Delivered counters, and along with the Generated data from the Envoy, the rest of the values can be calculated.

The update rate of the Summation values is (on my meter) typically between 5 and 10 minutes. When I use a 5 minute status interval in PVOutput, it means that a few times a day I might have consumption data duplicated (or blank) from one line to the next. If you want true 5 minute data, you can use Wattvision as an intermediary, and get your PVOutput data from there. Wattvision receives the Instantaneous Demand data, typically every 8 sec, and by totalizing & averaging that over each 5 minutes you can get the energy consumption & power in the interval. Because of the difference in timing, those data don't perfectly match the Summation values, but usually come very close.

The calculated Consumption value reported by PVOutput also suffers from some timing problems. Since the timestamps on your generated data won't perfectly align to the timestamps on your Net data coming from the Eagle, you might see some negative consumption values (reported as zero) on days when generation (clouds) or consumption are fluctuating rapidly enough for the timing misalignment to matter. I found that using Wattvision had fewer problems with this than using the Eagle uploader, but ultimately neither was good enough and I went to polling my own generation and consumption data and doing the calculations myself, keeping the data more synchronized. This was forced by the fact that my generation data comes from SolarEdge, which has very different timestamping approach than PVoutput.

[Sparta_SC]

thanks Sensij. I got a NEM approval email end of last month and also my meter was reset and I see "rec" and "del" values on the smart meter.

I did however only get ONE regular bill this month (not the one separated out from GAS). When i called SDG&E, the told me that tit takes them a couple of months to start providing NEM bill (which i can settle end of the year). Has this been your experience too?

and i am using wattvision as an intermediary between PVO and rainforest . Have emailed the NEM team to look at my account. will keep the forum posted..

[sabersix]

I did however only get ONE regular bill this month (not the one separated out from GAS). When i called SDG&E, the told me that tit takes them a couple of months to start providing NEM bill (which i can settle end of the year). Has this been your experience too?

The first month after ATO, I received two bills.

[rwb1921]

It took SDGE at least 2 months after approval before my SDGE online page changed to see the net use amount. They are not very fast in changing this over.
Then I could see the amount I was charged for daily, and then the amounts went negative on the days I over produced.