Solar production logging?

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Pcthompson
Posts: 4
Joined: Fri Sep 01, 2017 1:31 pm

Solar production logging?

Post by Pcthompson » Wed Dec 06, 2017 7:44 pm

I recently upgraded my solar inverter to a Solar Edge HD Wave with per-panel optimizers. I figure with GEM and Dashbox logging my per-circuit usage data I should also document the per-panel generation, right?

So now I have a problem- I have TOO MUCH information on the solar inverter. The solar generation is logged by:
-PSEG utility company meter
-State required revenue grade meter (Locus 120) required for SREC generation verification
-SolarEdge logging from Revenue Grade CT
-GEM connected CTs

Of course none of the daily solar production totals quite match- if I assume the Locus meter is the reference to compare to (as the SREC reporting source) I see a range from +5% to -1% over a typical 24 hour reporting period comparing the various logging devices..

It looks like some of the difference is due to different methods of determining daily generation. Apparently the Locus and Solar Edge meters only total the outgoing power from the Inverter. At night when the inverter is consuming 7-9 watts in idle mode (including two WattNode power loggers connected to the SolarEdge solar sub-panel) that continuous use is NOT subtracting from the daily generation.

On the other hand, it appears that the GEM and Brultech solar generation logging (configured as NET sources, displayed in GREEN in the Dashbox Overview below the total daily usage) totals up the solar generation plus the SolarEdge idle power draw which reduces the generation figure.

Both of these methods are valid ways to track the solar panel production, but it is a bit disconcerting to see differences between them.

I am sure that other GEM/Dashbox users out there also have solar panels. What is your solution to this issue?

Thanks for your input.
Pcthompson
Posts: 4
Joined: Fri Sep 01, 2017 1:31 pm

Re: Solar production logging?

Post by Pcthompson » Thu Dec 07, 2017 12:48 pm

To clarify- yes, it does make sense to have the solar inverter show true NET generation (including any non-production time power being used that slightly reduces the total energy that has been produced by the solar panels, inverter and related components.

What does bug me though is that the green outlined "Power Generation Right Now" figure at the top left of the Dashbox display stays outlined on a green background when power is being generated (-) or used (no sign), but disappears when the net figure is 0.

Perhaps the background could change from green to gray when the Generation indicator is actually showing consumption?
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