How to get mqtt sensor value chooseable in energy dashboard?

I get already data by mqtt. Therefore i have done the following stepts:

A) include in configuration.yaml

# MQTT Powergrid
mqtt: !include mqtt.yaml

B) mqtt.yaml

for example one value:

sensor:
  - name: "Powergrid in"
    state_topic: "homeassistant/powergrid/actual/in"
    state_class: measurement
    device_class: energy
    unit_of_measurement: "Watt"
    icon: mdi:transmission-tower-import
    value_template: "{{ value | multiply(1000) | round(2) }}"

Now i want to add this to energy dashboard. But this sensor is not showing up in dropdown.
How to do that?

thx.

Watts are a measure of electrical power, not energy.

The energy dashboard is for energy sensors. Not power sensors, which is what you have.