Why "From Grid" isn't back calculated after installing Solar

Have had my Sense meter > 1 year and love it. Just added solar and the production numbers are a great addition.

Seems like 1 issue though which is surprising. The TO and FROM grid data seems to only be calculated from the date I added solar around end of January. Before then, even though we used power in January FROM the grid, that usage is recorded in the “Total Usage” but as 0 From Grid.

This is going to muddy the reporting of current month, bill, and yearly data.

Why not just back calculate all usage prior to Solar as production FROM grid?

Raised a ticket few days ago but so far no real response from Sense Support.


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My guess would be since you weren’t using solar there are fields that aren’t generated. Then when you added solar it adds those fields similar to adding a row in an excel document and now some of the historical data is in the wrong column. Hopefully someone at sense can fix that.

Agree with your theory. Don’t bother counting to/from if Solar is not enabled, but once it IS enabled, it seems reasonable to apply a back calculation for the historical consumption, at least for the current affected periods (day, week, month, bill, year).

Maybe in some rare edge cases the assumption that FROM GRID = USAGE pre Solar is not as straight forward (e.g., generators, battery backup).

@davidduran , I’m a solar user, and for me the solar reporting transition seems correct. From Grid, To Grid, and all the other solar-specific “measurements” don’t exist until you have solar. In other words, just because Total Consumption = From Grid when one has yet to add solar, is no reason to call it From Grid.

Hi @Kevin1 - can you share a screenshot of your data?

Here is my January. Solar activated on Sense Jan 30 I believe.

In this case, for sure my bill from electric co is going to reflect close to 700 kwh usage, and it seems reasonable to me to call this “From Grid” as that’s where it came from, no?

Yet Sense reports 68kwh as it’s only considering my usage those last couple days of Jan.

Said another way, I would expect ongoing:
From Grid + Production = To Grid + Usage

But for this transition period it does not.

@davidduran, I have has solar since I installed Sense so I don’t have any transition months or years like you do. Looking at your transition, I can see why you might be surprised by the difference between Production and From Grid, but I’m not so big on backfilling a solar-only concept like From Grid (which is a companion with To Grid) to time periods that don’ have solar. If you want consistency, Production, Usage and Net will all be consistent.

I added my solar several months after I had sense. Back then, it worked correctly.


@ccook Interesting! The plot thickens.

Whether a bug or intentional, something seems to have changed in the “adding solar” process.

What does your “bill” view show? I can see how it would be frustrating for the calendars month. I’m assuming it’s how Sense calculates it and adding mid/late month screwed it up. Though I’d imagine it would correct itself next month.
While I don’t think Sense would be willing to re-write how it calculates. They might want to add a disclaimer or suggest enabling solar on the 1st day of the month or billing cycle to avoid of inform of this type of situation.

Same discrepancy just slightly different numbers.

From grid is ~100kwh less than what my actual bill is going to end up showing. This from the period between start of billing cycle Jan 24 & solar activated Jan 30.

At risk of beating a dead horse.

Just wanted to show the end of billing period discrepancy here that is not the end of world but seems like it could be easily improved.

Every number here in the Sense report is correct EXCEPT “From Grid” and “% Solar” due to the week of usage in the billing cycle prior to activating solar.

About 100kwh difference.

Also note, “From Grid” + “Production” != “Usage” + “To Grid”. Again about a 100kwh missing from the left side.

I digress.

Did you open a ticket for this? In your billing … do you have another line that says net or production in your bill? I would expect your from grid and your usage to match or be pretty close.

The “powered by solar” is calculated strangely, maybe more for those trying to design their system to be non-grid dependent with the use of a battery bank. For instance if you had 8 hours where you made 10,000 watts (80kwh) the whole time and only used 1,000 (8kWh) watts during that 8 hours. During the 8 hours you would be 100% powered by solar even though you produced 80 kWh and used 8kWh … that +72 kWh doesn’t make it 700%. Then for the 24hr period it would show you were powered 100% 8 of the 24 hours so you powered by solar 33% of the time for that 24 hour day. When sense populated that field and I had a day where I made 38kWh and used 26 kWh it showed up as 38% powered by solar… I was like ???

I’ve also wondered why they don’t put the dollar amount in the Net column, instead you have subtract production from usage then add my meter free or customer charge. For that billing cycle my bill would be 99-82=17$. + 15.86 my customer charge … ~34$ … they also won’t let you build a tiered billing or add in a meter fee.

Thanks ccook. Yes ticket raised, they said it is expected behavior and “as designed” although others here suggested it’s now how it worked when their solar was activated so I suspect still a bug.

Re the % Solar, I’ve seen the other threads on that and honestly am happy with how it works. Agree it is a bit counterintuitive if you are producing some multiple of your consumption, issue is WHEN you are producing it.

For me, lotsa power in middle 1/3 of the day more than covers our total need (on a sunny day), but there are still 2/3 of the day (morning, evening, night) where that’s not the case and I’m pulling from grid.

Best way to visualize this I think is the Meter trace. % Solar is really area under the orange curve that IS ALSO under the yellow curve. You can see lots of orange where this isn’t the case 3pm-9am.