Have a dumb bloutooth light, on for 12 hours a day - want to add power / energy - only energy sensor created ?

[vw-kombi]

I have a few things setup for 24 hours / all day in the house and they are all working fine.
This light however is for the stairs, I dont need an expensive one as it is just a timer.
This is the first time I have set the 'On Time', and when I set it to 12 hours (6PM to 6AM), the power sensor is not created, just the energy sensor. If I set it to 24 hours, then it is created like all the others.....

I'm wondering what the time is actually for therefore - Is it just to calculate the daily energy used (power configured x 12 hours)

In my use case, having an on and off time in here would mean I can track it properly - same as the schedule in the tuya app, and it can be added to my total monitored power.

[bramstroker]

That's correct, when you only supply on_time no power sensor is created because it's not schedule based.
i.e. powercalc just adds correct amount for 12 hour on during the day to the energy sensor.
But it does not know "when" the energy is consumed, so it won't create a power meter.

For your use case I would suggest to create an input boolean helper (Using Toggle helper in HA helpers section). For example input_boolean.staircase_light_on.
Create an automation which toggles this input boolean on 6PM and 6AM respectivily on and off.

Now create a virtual power sensor (https://docs.powercalc.nl/sensor-types/virtual-power-manual/), select the input boolean as source entity, select fixed strategy and supply the bulb wattage.

Hope this helps.

[vw-kombi]

Thanks for the reply - I am still learning all this stuff and have no idea what that is but I will research it. My experience in HA is fne=ding something I have already done, and trying to make it work in a new way, plus googling of course.

I came up with this added to the conf file, and this I create my usual 'helper' with left riemann sum for the energy value for it; :

  - name: "Stairs Lamp"
    unique_id: "Stairs Lamp"
    unit_of_measurement: 'W'
    state: >
      {% set power = 0 %}
      {% if now().hour < 6 %} 
        4.5
      {% elif now().hour > 18 %}
        4.5
      {% else %}  
        0
      {% endif %}

[bramstroker]

Yes that would be another approach.
I think you might also use this template to just create a virtual power sensor. Did not test it, but pretty sure it will work.
Just put the template in power template field.

You don't have to create riemann sum helper as well, because Powercalc takes care of that.
Just set the toggle create energy sensor on.
Under the hood powercalc uses same code as riemann sum helper for the energy sensors.

[vw-kombi]

I understand your answer now. It’s better as no config code needed. Plus it made me look at a few others things I did in config code that can be done better with the helper and automations. Thanks for that.