Monthly data not matching for usage

I am keeping track with a spreadsheet about daily production & usage (among other stuff: like comparing microinverters with stringinverter )

For production it is absolutely spot on the same in my spreadsheet and what sense reports.
For usage it is off since this month.
My spreadsheet is filled out with the values I get from sense on daily basis.

and my spreadsheet:
Screenshot from 2021-02-27 06-19-32

There seems to be a difference of 51.6 kWh
I added all the daily usage readings (i hovered over each day in the monthly overview) in a calculator and that ended up to be the same value as my spreadsheet.

Which makes me believe that the monthly value of the web interface of Sense is not calculated right.
When I compare last month of my spreadsheet & sense monthly overview, everything matches.

This month I added my hybrid inverter , meaning that my usage actually goes negative part of the day.
I asked for feedback about that in a different thread. Even sent an email to support@ but no response yet.

Could it be that is where the 51kWh “went” ? it just doesn’t show up on the daily values anywhere but somehow the total usage does include the fact it went negative?

Hard to see anything amiss from here though the differences between Total Usage - Solar Production and From Grid - To Grid are off by one another by about 1kWh - those differences should be spot on to within 0.1.

But if you are seeing negative Total Usage during the day, that’s not good unless you have an appliance inside the house that’s generating energy. Sounds like you have an energy source (the hybrid inverter) that Sense isn’t seeing through the solar CT. Or if the hybrid inverter has a battery, Sense might be seeing the energy when it is produced rather than when it flows into main breaker panel ?

My solar production is within 0.2kWh accurate, which should be considered a rounding error.

Correct, as my thread here describes:
https://community.sense.com/t/how-to-hookup-a-hybrid-inverter/13720/5

Basically I keep the batteries charged during the day with solar.
The unit is able to put energy back into the grid (sell mode) if the batteries are full and enough sun.
My MPPT charge controller tells me it is producing about 5kWh per day that in puts in “the batteries” but part of that is used to offset the load on the output and when there is more solar available going back in to the grid , but on the CT’s of usage of the sense.

Coming back to my original question:
Sense does not show negative values on the daily usage graph. When you mouse over you can actually see if shows eg -200 watt. Could it be that that energy, although not showing up in daily operations, does get calculated for the monthly totals , hence my missing 51.6 kWh?

So two things:

  1. I looked at a time periods where I had negative Total Usage back in Oct. (not for good reasons - my Sense monitor was misbehaving), and when I added the Total Usage in each bar, it summed to the the same 250.8kWh calculated by Sense. But you’ll notice that the totals for Mon and Tues were zero, instead of negative. I also noticed that the difference Usage - Production is very different than From Grid - To Grid which indicates accounting problems.

  1. I’m guessing that you want your hybrid inverter showing up on the supply side of the solar CTs if you want the Sense calculations to come out correctly. Sense adds the measured Solar Production to the Net Usage it measures to get Total Usage. You’ll get negative Total Usage if Sense is missing some of your solar / battery production, when your net usage is fairly low.

couple of things:
I am coming up with Monthly totals not adding up with adding each individual day measurement.
What do you do? come up with weekly measurement. Not what I asked.
Then you come up with from-to-grid, which is something totally different and has absolutely nothing to do with this case. You are only admitting you don’t understand what you are talking about.

Another total useless opinion. Another proof you don’t even understand what I am asking.
Trying to answer the other thread with just an opinion, no facts.
So out of 24 hrs a day, the hybrid inverter uses electricity for 21 hours at much higher power then the 3 hours it might put 150 watt back in to the grid. but your suggestion is to hook it up to the solar production side? Do you realize how silly that looks?

Could you do me a favor?
Don’t respond to my postings/questions any more!
It is clear this is out of the area of your expertise and sometime it is better to say nothing.
This is not the first “discussion” where this happened.
I will wait for a real experts opinion.

Thank you!

Danny
btw: Dutch Culture Taught Me to Be Brutally Honest: The Dutch Directness - Thrillist

OK - bye. Support should be able to help.

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This was absolutely awful to read. I’m going to address you with a bit more respect than you seemed to have used in your other responses here, but I will not give you another warning about this.

Next time you speak to anyone in the Community like this, you won’t receive a “watch your tone” message. You will be banned. We’re all adults here. Act like it.

A reminder for anyone who wants to act like a child when someone is attempting to help you:

  1. The people who are trying to help you with your issues are volunteers. Don’t speak to them like they are beneath you, or you will be banned from this Community.
  2. @kevin1 is as much of an expert on Sense as anyone that you’ll find in these forums. The amount of actual folks he’s helped on these forums is beyond what anyone else has done for this Community, by a significant amount.
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