Template sensors don't appear

Configuration
4

  1. Where are you putting this config?

  2. Did you restart HA or just reload your config? The first time you use any new integration you need to restart. Then after that you can use reload.

EDIT: Also to prevent odd results when one or more sensors are unavailable you should use an availability template in each sensor, e.g.:

template:
  - sensor:
      - name: "Total Electricity Consumption"
        unique_id: total_electricity_consumption
        state: >
          {{ (states('sensor.energy_consumption_tarif_1') | float(0)) + (states('sensor.energy_consumption_tarif_2') | float(0)) }}
        availability: >
          {{ has_value('sensor.energy_consumption_tarif_1') and has_value('sensor.energy_consumption_tarif_2') }}
        unit_of_measurement: "kWh"

More here: Why an availability template is important for energy template sensors