A new-ish garage door opening will have a DC motor and I assume most of the backup ones do. I’m not confident that signature is a charge cycle although it’s a native Sense signature so it may be artifacts thereof.
Here’s a Dyson charger for comparison:
As you probably know, just because you have smart plugs on the freezers and other devices doesn’t stop Sense from detecting the devices and components separate from the signature being sampled by the smart plug.
OK, for a frivolous exercise let’s say Sense has nailed the opener.
4 times a day (average) sounds possible (up & down & up & down).
8.8 kWh/yr and 1504X ==> 5.85 Wh per activation.
8ft ceiling = 2.4m
Lets say the door weighs 100kg (heavy one)
Assume 100% efficient “opener”
E = mgh = 100 * 9.8 * 2.4 = 2,352 Joules = 0.65 Wh
It’s amazing how little energy it takes to lift stuff!