Using Sense for sizing future solar hybrid setup

Let me mention, I am EE for over 25 yrs and was recently looking for a tool that would simplify process of estimating power consumption at my household. The data would be used to properly size solar hybrid setup (on/off/backup).

As some of you may know that task it’s doable with single phase loads (all plugged into outlet) however with two phase heavy loads like stove, ac unit, water heater and dryer it becomes uneasy as these are either hardwired or there is simply no popular pluggable energy meters designed for split phase loads.

Couple days ago I stumbled upon Sense on Facebook and after reviewing available information, decided to order standard non solar version to try. Installation looked doable per attached sheet but when removing front cover of my main electrical panel I noticed the main feed wires are not available. This is because my electrical grid at home uses two panels, one main panel installed directly under the city energy meter distributing 2-phase heavy loads and feeds 2nd panel for remaining loads (lights, wall sockets, etc). The primary panel is integrated with energy meter both use fixed solid rail, no wires present to put Sense current clamps. So my Sense cannot be connected as advised to capture entire feed from the grid into the household. Instead, I am only able to tap into one of 4 main sub branches at the time, either 2nd panel sub branch, ac unit branch, stove branch or pool pump branch. So it’s going to take either 4 Sense units or using just one monitoring each branch separately for some time and analyzing results later. That may create unwanted error in estimate because there is no guarantee every load will be turned on same way when monitoring one branch after another over different times, not simultaneously.

So the use of Sense in my case is limited to monitoring individual 2-phase loads. And of course estimating power consumption from remaining loads in bulk fed via 2nd subpanel.
But not all at once like Sense manual says.

Still, evem that is sufficient when I employ my own spreadsheet and log power consumption for each individual load in my home. At the end I will be able to summarize worst case scenario for kWh say overnight to properly size battery bank in my solar hybrid setup.

I installed Sense yesterday starting from 2nd subpanel and within few hours I already analyzed and estimated most of my loads fed from it for wattage. Now, I will wait a week and monitor to get data about time each load is used. Having both, I will have weekly kWh consumption separately during day and night and that is my goal. I will repeat process for remaining branches in my main panel, that will be much easier as eaxh5sub branch feeds only one load, either : AC unit, range or pool pump. The last one is easiest as it only takes measuring its power via sense and multiplying it by nunber of hours it’s turned on.
So after all this, I should arrive with average and worst case kWh power consumption during the day (sun hours) and during the night. Both will allow to properly size PV array and inverter size, second will allow to size battery bank. With Sense used, this process is finally possible also for two phase loads.

Thanks, Sense!

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