How to properly read power consumption?

I’m attempting to modify the source code of a smart app that I found on GitHub. I would like this app to monitor the power consumption of a fridge, but having trouble finding exactly which data point to read.

Looking at the device itself on the SmartThings Groovy IDE, the fridge has a data structure called powerConsumption, with some sub-properties called deltaEnergy, power and energy. However the deltaEnergy and power properties are always zero, while the energy property has a fixed number that has not changed at all in the past 48 hours (since I started looking at it).

Note: I am reading the powerConsumption property by looking at any devices which have the powerConsumptionReport capability.

Does anybody know what is the right way to look at power consumption?

EDIT (Jun/2025): for the record, I never found a proper solution for this, but also it’s no longer a problem for me since a few years ago I moved on to a new fridge that properly provides the information I want when integrated with Home Assistant.

Welcome @badnetmask! Can you share the link to the SmartApp’s repo, please? I will take a look.

The status of the powerConsumption capability is “proposed” so it would be better to use powerMeter instead.

Doesn’t look like my device exposes powerMeter. Is there some flag I should enable for it to be exposed?

To expand on what I said before: the app can read powerMeter just fine, and I know that because I can see power from some smart plugs, but that’s all. The fridge is not exposed when listing for powerMeter.

Ok, as I understand, you already have the fridge installed in the SmartThings app but the values shown in IDE don’t make sense.
Have you checked the device status using the API?

I’m not checking the API, I am developing a Groovy app on the SmartThings hub.

I checked your fridge status, I see that the power attribute is not being read. So, I need to open an investigation to find out why. Please, send an email to build@smartthings.com with this information:

  • Device model
  • How did you install the device? (through the app, or another method)

Hello j have a samsung fridge and it shows the power consumption on the frige but will not show on the smart meetsr reading side can you help please

Thank you

Hi, @Muschamp.
Sorry for the delay. Can you provide more details, please?

What do you mean by “will not show on the smart meter reading side”?

Hi,

I’m new here. I have a similar problem with reading and understanding my power consumption values. I have installed the SmartThings integration in Home Assistant and want to display the power consumption of my fridge on my dashboard. The “power” entity that the integration is providing gives me an abnormally high value. Sometimes this value is 435W, sometimes it shows 1500W, and on rare occasions, a peak of 3500W is displayed.

So, I know that the power value is measured periodically, roughly every 15 minutes.
This is written here in the official documentation and also visible as the time between the “start” and “end” values from the json picture which can be seen a little further down:

But how is this power value displayed in the first place? Is there a measurement every minute about the current wattage and are all values summed up together?

My fridge is only exposing the powerConsumptionReport. No powerMeter or any other value.

Just for comparison, I plugged in a Zigbee smart plug which can also measure power consumption and updates every few seconds if a change in power is detected and shows significantly lower values.

If my fridge were really drawing 3500W of power, shouldn’t the fuse trip or get burned?

So… how is the power value calculated?

Best regards.

I think you’re a bit confused.

Power (powerMeter.power) is the instantaneous usage – how much electricity a device is using right now. Doesn’t matter if it reports this every second or every hour. Measured in watts (W) or kilowatts (kW). Kind of like a speedometer.

Energy (energyMeter.energy, powerConsumptionReport) is the total amount of electricity used over time. Measured in watt-hours (Wh) or kilowatt-hours (kWh). This is more like your odometer.

So if your smart plug or fridge says 100W, that’s what it’s using at the moment. If it says 2500 Wh, that’s how much it used over, say, a day or week.

Older fridges use a lot of power (Watts) for a short time to start the motor and that’s why you see these spikes.

My “AWA” is having issues since a week, so I have to use an old screenshot where you can hopefully see the difference:

Had a look at your screenshot. The deltaEnergy is the energy used between start and end (/timestamp). energy is usually the total since the last reset of the device.

1 Like

Hi @CurryPlayer
Just to confirm, deltaEnergy is the amount of power used in the period.

The problem I’m facing is that the Smartthings Integration in Home Assistant accesses these values from the Smartthings API (the picture showing JSON code from my previous post). As far as my understanding goes, the value powerConsumptionReport.powerConsumption.power should be represented in Wh (Watt-hours), right? Because the powerConsumptionReport gives details about a specific time period, not a particular point in time.
But the power value is represented in Watts through the Home Assistant Smartthings integration.

The Smartthings API reports the following value under the capability powerConsumptionReport with its attribute powerConsumption:

{
    "energy": 497667,
    "deltaEnergy": 13,
    "power": 613,
    "powerEnergy": 141.72165887143876,
    "persistedEnergy": 0,
    "energySaved": 0,
    "persistedSavedEnergy": 0,
    "start": "2025-06-16T18:29:24Z",
    "end": "2025-06-16T18:41:16Z"
}

The API response for the value power doesn’t have a unit to display. So, because it says power, it should be in ‘watts’, not ‘Watt-hour’ or any other unit, right?

So, does the Home Assistant Smartthings Integration just return a wrong unit or is my understanding still not correct?

Just to clarify any misunderstandings… I have two entities to measure the power of my fridge. On the left is the power entity of the fridge itself. This value is provided by the Smartthings Integration via Home Assistant. On the right side is a ZigBee Smartplug that measures the power of the fridge:

If both devices measure the power of the fridge, how can they differ that much? The values from the smart plug makes way more sense than the values provided directly from the fridge itself.

Sorry for the inconvenience, but I just want to get rid of my confusion and get this right.

Best regards.

Edit: For reference, the fridge I’m using has the following model number: RS6HA8891B1/EG

You’re correct that the “power” attribute uses watts (W) as its unit, but it represents instantaneous power.

We’re not sure how the Home Assistant integration works exactly, but is it possible for you to configure it to use the deltaEnergy attribute instead of power? That value is reported in watt-hours (Wh), which might better match what you’re expecting.

Also, since your device includes this capability, it should be supported in SmartThings Energy. We suggest installing the SmartThings Energy app (found under the Life tab) to see if the chart shown there makes more sense. That application relies more heavily on the deltaEnergy value.

Devide the smart fridge power value by 10 and be done with it! :wink:

Seriously. Do that and compare the graphs a few days later.

You should also log in here, go on each device and check the values in the attributes and especially the events - since the ST-HA integration is SSE, if I remember correctly.

@Itati The problem is not the Home Assistant SmartThings integration. It pulls values directly from the SmartThings API. The SmartThings API itself is providing these extremely high values.

The reason I asked about the units for all values within the powerConsumption object in the JSON is that the developer documentation doesn’t provide these information. For the powerConsumption object it only states “energy and power consumption during specific time period” (see documentation here). The JSON schema also doesn’t specify any units (see documentation here).

@Andreas_Roedl I’m currently writing my Bachelor’s thesis on the energy consumption of IoT devices. Therefore, I unfortunately cannot simply divide the value by 10, as this would falsify my results.

I am retrieving the consumption data via the following API link:
https://api.smartthings.com/v1/devices/XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX/status
(The actual Device-ID has been replaced with X’s in this example)

The API returns the following powerConsumptionReport object:

"powerConsumptionReport": {
    "powerConsumption": {
        "value": {
            "energy": 500136,
            "deltaEnergy": 19,
            "power": 852,
            "powerEnergy": 157.68786165714263,
            "persistedEnergy": 0,
            "energySaved": 0,
            "persistedSavedEnergy": 0,
            "start": "2025-06-18T15:49:54Z",
            "end": "2025-06-18T16:04:38Z"
        },
        "timestamp": "2025-06-18T16:04:38.238Z"
    }
}

If the power attribute is truly output in Watts by the SmartThings API and represents the instantaneous power, then this value must have been calculated incorrectly. My refrigerator has an average power draw of 60W (measured with an external power device). But the API responds with an instantaneous power value from at least 800W or higher. That would be far too much for a refrigerator.

If powerEnergy is the consumption over time, it should be easy to calculate. The period for the calculation is provided by the start and end attributes. The period is thus 14 minutes and 44 seconds, which is 14 * 60 + 44 = 884 seconds. If I multiply this time by the instantaneous power provided from the power attribute by the API, I get 852W * 884s = 753,168Ws (Watt-Seconds). Divided by 3600 seconds, this equals 209.213…Wh (Watt-Hours). However, this is still significantly higher than the reported powerEnergy of 157.687…Wh.
So… what am I missing?

Could the refrigerator’s sensor be damaged, causing the high wattage reading? Or is the wattage calculated differently?

My refrigerator is a RS6HA8891B1/EG, if that helps with the analysis.

I just want to know how these values ​​are to be understood, and why they are so high.

Best regards

We asked the team, and they mentioned that they’ve also spoken with Home Assistant developers about this particular capability. However, this capability is designed specifically for interacting with SmartThings Energy. So, while you can see its values in the API, it’s likely that a special “rule” is being applied to calculate and interpret those values within the app.

Therefore, outside of SmartThings Energy, this information may appear inaccurate. Unfortunately, we don’t know the exact “special sauce” behind it, as much of that configuration depends on the manufacturer’s implementation.