I’m trying to watch my energy usage (without shelling out $200+ for some fancy meter reader, but it may get to that point 
) and I know that HVAC systems are huge energy draws.
In an attempt to gamify my HVAC usage, I’m creating a “last month’s HVAC usage” and a “this month’s HVAC usage”. This month’s HVAC usage looks weird, but I have data.
Here’s my sensor config:
- unique_id: last_month
platform: history_stats
name: HVAC Heating Previous Month - Heat
entity_id: climate.thermostat
state: "heat"
type: time
start: "{{ now().replace(day=1, month=now().month-1, hour=0, minute=0, second=0, microsecond=0) }}"
end: "{{ now().replace(day=1, hour=0, minute=0, second=0, microsecond=0) }}"
- unique_id: this_month
platform: history_stats
name: HVAC Heating Current Month - Heat
entity_id: climate.thermostat
state: "heat"
type: time
start: "{{ now().replace(day=1, hour=0, minute=0, second=0, microsecond=0 ) }}"
end: "{{ now() }}"
Two questions:
First, I’m guessing the reason why I have sudden drops in data is due to recorder dropping the 11th day’s history (since the default is 10 days). Can someone confirm?
Second, with the history retention in mind, what is the best practice for keeping track of stuff like this? I assume the most straight-forward way would be to increase my history to 60-90 days but I imagine the database would grow exponentially.
Or is it better to have a “yesterday” HVAC use and have automation add this number to a counter-helper?
Thanks!