So this morning we had a power outage between 9:10 and 10:46 in the entire neighborhood. Homey crashed instantly of course. I’m also using the energy dongle.
However, why did it register power usages? Does he just guess? Assume that my power usage would be the same while Homey was down? Also why the weird dent in my total import? What is happening here?
Also, can it be fixed? Doesn’t feel very reliable tbh
You should issue a support request with Athom about this: https://support.homey.app/hc/en-us/articles/360015784034-Submitting-a-support-request
Insights is unreliable by design, because it aggressively averages down values. I can’t really explain the first graph, but the second one suggests it might have written a “0” (or at least a substantially lower value) to the database just before it crashed. That might point to a bug, where the dongle mistakenly used a default of 0 when it couldn’t read data from the meter (that’s all conjecture on my part though, best ask Athom to explain).
Can it be that Homey just keeps recording the current value, until that changes? During the power outage nothing changed as Homey was down. When you powered Homey up again and Homey received a new consumption value, only then it updated the power usage. The power consumption in between is a straight line, as Homey did not receive and power usage updates during that period.
That would make sense for the second graph, since it’s a monotonically increasing value, but not for the first one, which is an ephemeral value.
And from what I understand, the graph are showing 6 hours (I think the ‘jan. 13’ marker is midnight) while the outage only lasted an hour. So the flat line in the first graph points to something being wrong.
That could be indeed. Or: the screenshot if from a 6 hr period and was taken around 15:00 hrs. The right hand part of the graph is not included in the screenshot (cut off). The the start of the graph would be around 9:00 o’clock, aprox. when the outage occurred. But it’s just a guess, of course 
.
Anyway it is weird behavior in the end.
You might be right. This is what a 6-hour graph looks like:
The ‘jan. 13’ marker is used as the first hour marker for the graph, not midnight as I thought.
So that could explain the flat line in the first graph (not nulling “unknown” datapoints but continuing using the last recorded value before the crash.
@robertklep and @SunBeech , it’s indeed the 6 hour graph. Which starts around 9, and as soon as the line goes flat, it’s 9:10 and at 10:46, it stops and also the weird dent in the 2nd graph shows up.
The weird part is, the kWh in the 2nd graph stayed the same, on the dot. Meanwhile it did “register” 145W for over 1,5 hours.
Could I state the fact that both numbers are unaware of each other? They just read P1, drop the numbers and that’s it right?
Which would mean that even during a power outage Homey won’t check with the total consumption value what the average power consumption was.
I think that is the way Homey does it for every capability: if the value does not change (or more accurately, if Homey is not aware of a change) it considers the value as current. So in your graph you get a straight line.
I expect that capabilities, like the current and total consumption, are treated by Homey independently. Homey just displays (and records) the values it receives.
Maybe when your Energy Dongle powered on again it re-initialized the communication which led to the zero value in the bottom graph.
Which would be a bug, since it should only be recording the values returned by the smart meter, which does not reset (imagine if it did 
).
FWIW, I really wonder if Athom has ever considered that people could get a new smart meter. Mine was replaced a few months ago, so all counters were reset, but HA has some specific measures in place to handle that.
