Thanks to the chain communication, I was able to network up to 60 controllers!
In about 1 second, the controllers read the sensor, receive the data from the previous controllers and transmit the packet to the following ones. After that it goes on deep sleep mode for 30 seconds.
At the end of the chain I use an esp8266 as gateway that transmits all data via serial to a PC where I have created a supervision application, with geographical map, alarm management and data recording. Hope you like it.
This is the project page: https://hackaday.io/project/186064-green-detect
This is the Youtube video presentation: