I've been developing my home automation stuff recently. I have a esp32 calling home over wifi about every minute, and I wanted to try a battery version. I just happened to have two rechargable AA and a AA battery holder.
You're very correct the wifi is a huge drain. I configured it to go into sleep mode between measurements and I was able to get 3x the life out of it, but for 2 AAs without a real battery circuit, it just meant about 36 hours.
I'm excited for the zigbee/matter chips, I'd like to really get power down so I can embed sensors in things like guitar cases.
It's been a while since I used it but from what I remember it works really well between ESP devices and you can certainly do a many to one/gateway approach. The range and power consumption is outstanding all things considered.
Would BLE work for your use case? I have a few ESP32 projects that fire out occasional sensor readings using BLE advertisements which is a lot faster and also lower power than trying to hook up to WiFi on every wake cycle.
You're very correct the wifi is a huge drain. I configured it to go into sleep mode between measurements and I was able to get 3x the life out of it, but for 2 AAs without a real battery circuit, it just meant about 36 hours.
I'm excited for the zigbee/matter chips, I'd like to really get power down so I can embed sensors in things like guitar cases.