Counting how many days elapsed in Utility Meter

Configuration
21

Just to be clear I didn’t mean you needed to all three. Just one should do it. E.g., you don’t need entity_id in your solution:

- platform: template
  sensors:
    days_kw:
      value_template: "{{ ((as_timestamp(states('sensor.date') ~ ' 00:00:00') - as_timestamp(state_attr('sensor.power_yearly', 'last_reset')))/(60*60*24))|int }}"
      friendly_name: 'bimonthly'
      unit_of_measurement: "Days"

It will automatically find sensor.date and know to update when it changes.

22

Thanks Phil, I’ll update the sensor.