After installing my Sense a few months ago I’ve noticed a large Always On category. Most of my big items have been detected, and I’ve put a few smart plugs to monitor the rest (TV’s, monitors, desktops, etc.) I added the Flex Sensors on a breaker that goes to a sub panel when it was installed. I am curious if Sense net’s that usage out of the Always On/Other categories, or is it double counting the energy? Since I installed the Flex Sensors in the beginning, there weren’t any devices discovered yet.
To start with, most devices have both a dynamic / switched and Always On components to them - so it takes a little more digging to understand how to sort out Always On when dealing with devices on Flex Sensors or smartplugs vs. native detections.
As an example, my upstairs furnace on a smartplug uses a constant 8W (Always On) to power the internal control board and the associated thermostat - that device level Always On is even calculated by Sense. When the AC kicks in, the furnace blower turns on, causing the usage to go to 350W. That additional 342W is what I would call a dynamic power component. Sense native detection would only be capable of finding dynamic components part, but not the Always On part, but smartplugs/Flex Sensors see everything.
So when you add a smartplug or Flex Sensor, here’s what happens:
- Sense uses the measurements from the smartplugs for the device
- Sense subtracts off the entire usage of the device(s) on the smartplug(s)/Flex Sensor(s) as well as all the other devices it has detected as on at that point in time (including the house level Always On) to calculate the Other bubble.
- Sense does NOT currently subtract off the calculated Always On for the smartplug from the total house Always On.
- So just to restate you have to think about the device on the smartplug/Flex Sensor as having two different components, an Always On part and a dynamic part. Each gets treated a little differently for purposes of accounting. When you add a device on a smartplug, Sense will subtract off the full usage of that device (Always On and dynamic) to get Other. But the Always On component from the smartplug is NOT subtracted from the house level Always On. So the Other gets reduced a bit due to double subtraction of the Always On part.
- In most cases, the Always On is much smaller than the dynamic part of the device on the smartplug / Flex Sensor, so this double subtraction doesn’t result in a big issue with respect to Other. But there are some cases where people have very large Always On loads on smartplugs/Flex Sensors - in those cases Sense is going to offer up confusing results.