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Problem: My kids and wife would start Air conditioner at lowest temperature (16 degrees Celsius) and forget to switch them off. At one point in time my electricity bill was 50% of my house rent.

Solution: I used Home Assistant and Frigate (local NVR) to detect if there are humans present in the room, if no humans for 10 mins, switch off everything. I actually use a combination of things to detect human presence, some of the things include motion sensor, PC active, user sleeping (10 PM to 8 AM), there’s also a switch I use to turn on sleep mode if I’m taking an afternoon nap (The switch automatically turns off after 3 hours). I also use a template to measure if the AC temperature is below 22, if it is, I set it to 22 degree Celsius. The automation above saved me 15-20% on electricity bill.




man! i hope your wife doesnt figure this out. ``` wife walks to thermostat - set 16C, walks away. thermostat: 22C! wife pikachu face - set 16C thermostat:.... ```




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