Hi everyone, I’m building a perimeteral alarm system for my home and I’m not sure which transmitter board to use for my sensors.
The ESP32 is not highly recommended due to high power consumption, XBee probably consumes less but is very expensive.
Can you suggest some other transmitter board that can be used with the home assistant?
Thanks
What type of sensor?
Nice devices 
From what I can see, it may be possible to hack a cheap Zigbee contact sensor to use as transmitter. These sensors use a reed (magnetic) switch, which you can desolder and replace by two wires that you can subsequently use with the N.O. contacts of your PIR sensors.
Similar to the “rain meter hack”: Portable rain drop sensor made with Xiaomi door sensor
The Aqara sensors last a long time with a battery, although using them outside will limit their battery life if it tends to get cold.
Thank you, is the sensor SONOFF SNZB-04 similar? Can I use this sensor with a small hack?
I think I need something different, I need more GPIO, for example for tamper output.
Or more sensors 
They are relatively cheap.
The Sonoff device looks like it can be used, but I don’t have any experience with it. It uses a CC2530 which isn’t a super lower-power device AFAIK.
An ESP32 could still be useful as you can put it in deep sleep mode and wake it using an external input (like an alert).
Yes, but my concern is detecting the “offline” status when using deep sleep.
It will always be offline except when there is an alarm and therefore I would not be able to prevent network problems.
Which zigbee chipset should I look for for the lowest power consumption?
JN5169?
The JN5169 is used by a lot of Aqara devices, and they have very good battery life. I have no programming experience with them, though.