Solar eats my Always-On number

I am in the process of adding solar, and in testing the panels and micro inverters I have been running a panel into my home power thru the Sense Solar CTs.

It’s been fun seeing actual solar production in the lower left of the Meter display, but after having it up for a time I am seeing a strange thing, the Always-On has changed size. It is typically around 400 watts, but after a day of solar generation, it changed to 28 watts right now. And since it’s cloudy out, there is a big grey Other bubble.

Shouldn’t the Sense software KNOW that solar is coming in and leave the Always-On alone? I haven’t seen the full power of my solar system (permit still not approved) but I was expecting I would still see Other and Always-On in addition to any identified devices and how much they are drawing. I get that less is being drawn from the grid but this is about tracking my power use, not my power bill.

I have Sense with an 8kw solar array, and I definitely don’t see that behavior. And, I totally agree, this is about power usage so your solar generation shouldn’t affect any consumption numbers, including always on and other.

I’m not sure what you mean by “I haven’t seen the full power of my solar system (permit still not approved)”, but around here you can’t connect Sense to the grid at all without the permitting completed. So, if you are running the solar but not grid connected I have no idea what Sense would indicate. Do you perhaps have your own battery storage, something that’s getting more popular as utilities continue to trash grid connected solar?

I suggest connecting Sense support directly. They may be able to help you sort out this strange behavior.

Sounds like you are testing your solar system with just a panel or two connected to the grid ?
I would be interested in seeing your power meter waveform for the past 2-3 days. I’m betting that the change in Always On is either not connected to he solar addition, or only a secondary effect of your solar install (did you turn off your mains for a bit to go live with solar ?)

Look for any places in the past couple days where your power meter drops to zero.

Good to hear it’s not normal.

If I am watching the sun come up and I am using 500 watts, as the solar watts number rises the other number (with the green plug) gets smaller by that amount.

Should the solar number be negative? I notice you can put the CTs on one way and the number is negative, and the other way positive. Not sure which way the software is set up for. Perhaps that is why the number when down, it did make it to zero for almost a minute at one point.

I have a working solar setup, and in my experience.

  • Solar numbers shouldn’t show up as negative anywhere within Sense if the calibration, etc. goes correctly. Support can help flip polarities if setup didn’t go right.
  • Solar Production and Total Usage are somewhat intertwined, so if you do have negative Solar Production, it can affect Total Usage. Remember, that the Sense mains CTs measure Net Usage. Sense has to re-sum Solar Production plus Net Usage to create Total Usage in a solar household.
  • And a negative Solar Production can shrink Total Usage resulting in lower than expected Always On (I have had a negative Always On before when dropouts have helped contribute to negative Total Usage)

Solar numbers should show up as positive, just like utility numbers. Since you want to be monitoring usage, you are ”using” both solar and utility power. The instructions for the solar CT’s provide for that.

So, I suspect that you have the solar CT’s flipped over. Interesting behavior, though. Makes sense (so to speak) that it’s behaving that way.

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@israndy: You wrote: " I haven’t seen the full power of my solar system"

Just an FYI, your best solar month will be June (max hours), but sometimes in May having large clouds reflecting from the east when the sun is in the southwest makes for an additional boost. Plus the temperatures are lower then than later in the summer which helps just a little.

So you won’t see the maximum possible until next year is my suspicion. YMMV!

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