Estimate Power Usage From Current Readings

Configuration
1

Hello All,

I finally set up my current meter readings and I can see a graph of historic data with max,min, and mean values…

I would like to convert this to watts by multiplying it to 220v (later I’d put in actual voltage from a sensor) and then sum the hours to get KWH per day…

Is it possible? How can I get this done? Markup card maybe?

Markdown code:
{{ (states('sensor.watermotor_gridcurrent')| float * 220)}} Watt
but this only gets the wattage right now

Thanks in advance…

2

Use a template sensor to multiply your current and voltage to get power.

Use the Riemann Sum integration to integrate your power sensor with respect to time to get energy:

Be careful which method you pick. Nine times out of ten the left method is better than the default trapezoidal method.

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3

Ok So I added a helper of type integration and set it to be hourly, it automatically says these are Ah values.

Then in a markdown card I had this:

## Power Meter
Now: {{ states('sensor.watermotor_gridcurrent') | float * 220 | round()}} Watt
This Hour: {{ states('sensor.power_usage') | float * 2.20 | round(default=0)}} KWH
Today: {{ states('sensor.power_daily_usage') | float * 2.20 | round(default=0)}} KWHD

Which looks like it works ok (I have to wait to accumulate more data).

BUT the first line shows values such as: 123.2000000000002 Watt So it won’t round and it’s driving me crazy haha.

@tom_l

4

You are rounding the number 220.

Put some parentheses around the whole expression, then round.

Now: {{ ( states('sensor.watermotor_gridcurrent') | float * 220 ) | round()}} Watt
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5

@tom_l Thank you so much now it works with rounding of values

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