Create kWh sensor knowing heater state + fixed power

[andypnz (Andrew Palmer)]

Hi. I have a current sensitive relay that (via and ESP32 / ESPHome) tells HA if a heater is on or off.

I know the power of the heater in kW. I would like to add the heater as a “Monitored individual device” in the Energy Dashboard.

How do I create a new sensor that will use the heater state (on / off) + known power and calculate kWh as a ‘fake’ sensor the Energy Dashboard can use?

[tom_l]

Create a virtual power sensor:

Powercalc - Virtual power sensors

In the last few weeks I have been working on a custom component to get virtual power sensors for your lights or other devices. It is stable enough right now to share it on this forum and make dedicated topic for it. The component provides multiple strategies to calculate estimated power consumption. One of the most interesting is the LUT method (using lookup tables). Some community members and me have taken measurements for all kind of different brightness/hue/saturation settings and their resp…

Then use the Riemann Sum integration to calculate the energy.

Integration - Riemann sum integral

[tom_l]

One issue you may have is that the Riemann sum integral is only calculated when the power sensor updates. Not sure if there is a way to force regular updates in powercalc.

[andypnz (Andrew Palmer)]

Thanks… I have added the power sensor and will see what sort of values I get Thanks again…

[MiguelAngelLV (Miguel Ángel)]

You need create a power sensor with a template that return 0 when the heater is off and the power when the heater is on.

After that, you can use a integral to create a energy sensor using the power sensor.

[bramski (Bram Gerritsen)]

Powercalc will force regular updates (every 10 minutes) even if the value doesn’t change. You can even change that with force_update_frequency option.
No need to create a riemann integral sensor manually. Powercalc will do so automatically for each virtual power sensor by default.

[tom_l]

Nice! Powercalc makes it very easy then.