where to put sensors

configuration.yaml

# There are three ways you can add your sensors to Home Assistant, and they all start in the configuration.yaml file
#
# First you can just add them directly:
sensor:
  - platform:
    name:

# Or you can create a seperate file like sensors.yaml, 
# you will need to of course create the sensors.yaml file first but add this to your configuration.yaml:
sensor: !include sensor.yaml

# then after restart will will load any sensor that in that file. 

# Or if you want to get more organized, you could go with a directory of yan files dedicated to sensors. 
# This way you could create a folder called sensors and in that folder have a power.yaml file for any power based sensor
# and may be one called stats.yaml for statistic based sensors. 
# you could then use this so that home assistant just loads every yaml file in that directory:
sensor: !include_dir_merge_list sensors