I have a pretty simple smart thermostat without many fancy features. Every Spring and Fall I tell myself I should set up some kind of system where if the outdoor weather is good enough, maybe I dial back the heating / cooling, maybe send myself a text to open windows, etc.
Small example: I normally keep my house at 72 in the summer, but if it’s up to 76 or so outside, it’d be nice if the thermostat turned off the cooling. I could manually turn it back on if I have guests over, etc.
I’m sure some of this logic would be easy to code myself, but wanted to check out what anyone else is doing first.
Using home assistant.
I have central (water circuit based) heating with individual control per room. Additionally I have a weather station on my roof that tracks the sun and wind,temp, etc. and presence detectors in almost all rooms and electric blinds. The components are all KNX based, the logic part is home assistant based.
Basically what we do: I have a “normal mode” that is supported by two addon modules. Normal mode means:
On schooldays the system tracks when school starts. If none is present in the kids rooms for more than 30min it assumes the kid is gone and goes into energy saving mode for that room (18 instead of 21). The system then looks when the kid is likely to come back and puts the room temperature up on time.
Our offices are always in energy saving temp and only get into normal temp once someone has been there for 15min or one of our computers is put on - both the wife and I work home office full time,but travel a fair bit.
The system tracks if our mobile phones are “pingable” locally. If they aren’t for 30min it assumes we are all gone and puts the whole house into “away” mode,including reducing the temperatures. Then it looks at our outlook calendars (and the school schedule) and puts the temperature back on as required.
Additonally a room that has a window open is always cut off from heating and the system sends a message when the outside temp is either too hot or too cold after a certain time.
Additionally we have two prediction based module The system looks at three different weather predictions (my area is a bit of a problem for these) and creates a mean expected minimum and maximum day temperature.
If the expected max and min is below a certain point it switches on “winter mode” - this means the system tries to keep the shutters up as much as possible and open them as early as possible (based on the sun position) so the house absorbs as much sun as possible. Doesn’t help that much,but at least a bit. Additionally the time for “open window notifications” is reduced.
If the expected max is above a certain degree the system goes into summer mode. Then it’s basically vice-versa. The system tries to keep the blinds/shutters down as much as possible according to the position of the sun and opens them only after the sun has passed. That works fairly well and reduces the room temperature significantly - in the worst room around 3.8° on average. It also reminds the inhabitants to open windows in the morning when it’s still cold and close them in time.