Hi everyone!
So I’m happy to say that my system was issued PTO and turned on a little more than a week ago, and I just had a quick question regarding the data in Enphase Enlighten and how it compares to that of my utility.
When I look at the “imported from grid” data in Enlighten and compare it to the “consumption in excess of generation” from my utility’s smart meter, I get the following.
| Date | Enlighten (kWh) | Utility (kWh) | Δ% |
|---|---|---|---|
| 2/18/2022 | 21.7 | 29.457 | 36% |
| 2/19/2022 | 11.8 | 14.146 | 20% |
| 2/20/2022 | 17.4 | 18.949 | 9% |
| 2/21/2022 | 15.1 | 16.205 | 7% |
| 2/22/2022 | 9.6 | 10.26 | 7% |
| 2/23/2022 | 48.1 | 50.447 | 5% |
| 2/24/2022 | 75.9 | 77.218 | 2% |
| 2/25/2022 | 62.0 | 63.378 | 2% |
| 2/26/2022 | 52.0 | 53.128 | 2% |
| 2/27/2022 | 23.7 | 27.433 | 16% |
I know the data won’t be a perfect match, as I believe the Enphase consumption CTs are +/- 2.5%, while obviously the utility meter is “revenue grade.” But the data can vary quite a bit, anywhere from 2% to 36%.
The consumption CTs are installed around the L1 and L2 wires emerging from the top of my main service panel, with the arrows pointing down towards the loads. No sub panels. And the consumption meter in Enphase ITK is set to loads only, because my PV is connected via a line-side tap above the CTs on the L1 and L2 wires on their way to the meter.
Does anyone have any thoughts? If the C1 and C2 CT meters were swapped to L2 and L1 in the service panel, would that explain it? Am I missing something else entirely? Or are these just normal variations?
If you’d like to see more data, I’m at The Solar Collective 11.250kW
Thanks for all your help!