How accurate is accurate? (Sense+Solar vs Tampa Electric) **spoiler IT'S VERY ACCURATE**

I’m starting to become very confident in the data accuracy of Sense for my installation.

I have had Sense installed since the end of January 21’ and I recieved PTO in February. This gives me 2 full months of net metered bills going for comparison. My utility is Tampa Electric and they do not provide any real-time, daily or other production/consumption dashboards or data. Just the monthly statements with power uses, and power imported from my solar array. Perhaps in the future more granular data will be available but for now I’ll just compare Sense data to the monthly statements.

In order to match the utility bill I export a report from the Sense dashboard for the entire year in daily resolution and then pivot table out the days for each bill and focus on two key data points. Those are “Mains” and “Solar” under the Device ID column. From there I look at the values contained in the kWh column for Mains and Solar respectively. If you sum those two values - “Mains” will be a positive number and “Solar” will be a negative value - you will end up with your net consumption or production for the day.

Here is what my data table looks like with everything but the Mains and Solar data filtered out.

Here is my pivot table that sums up the net usage and includes my data from the April and May bills (which is March and April data). The reporting dates float for my utility from month to month so I have labeled the specific dates to help me keep track in the Pivot table labels at the top. Each month I will do a new year to date export and update the pivot tables for a new month.

Sense Data April-May

Now let’s look at the actual numbers from the screenshot above. My utility bill states that I imported 1,120 kWH and Exported 1,796 kWH in the April bill and imported 499 kWh and exported 2,094 kWh in the May bill. This is a net export of 676 kWh and 1,595 kWh for the April and May bills.

Comparing to Sense data Sense shows a net export of 676 kWh and 1590 kWh for each month. Thans less than 0.5% variance between the two datasets for each month! That is OUTSTANDING especially given the limited and summarized data that is available from my utility.

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Nice work ! Just added to the summary of user comparisons. More and more, it’s looking like any substantial Sense differences vs. utility measurements are due to either:

  • Sense install issues (missed circuits or not-fully-closed CTS)
  • Utility issues (estimated reads vs actual from a smart meter, irregular monthly meter readings)
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