@cathoderay and of course others. Has anyone tried to get energy out figures from Midea Smart Home? I am now getting energy in, energy out and COP but the energy in numbers (and therefore COP) are nonsense. For example, November 1st showed energy in of 79kW while my actual total energy usage for that day was 33kW and my base load (without heat pump for heating/DHW) is around 13-14 kW so max for heat pump should have been in the region of 20kW. Given how far out that is, I have no idea whether to trust the energy out number, which was showing at 118kW, which implies a COP of 7.75 for the day as a whole based on my actual energy in number. Very frustrating!

@pash44pump - I stopped using the Mide app ages ago, so my memory is hazy, but I vaguely recall (at least I think I do) two things:

(1) it uses total cumulative kWh in and out as its basic data, ie lifetime kWh in and out. Thus if the energy in is 100kWh at noon today, and it was 97kWh at noon yesteday, then i have used 3kWh over that 24 hour period. It uses the lifetime data to do the interval calculations

(2) it uses integers (whole numbers) for this lifetime data. Over longer periods, that's OK, but over shorter periods it can cause rounding errors.

Note that energy is measured in kWh, not kW, which is power. 1kW of power (say a 1kW conventional electric heater) on for 1 hour uses 1 kWh or energy.

Posted by: @pash44pump

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I have no idea whether to trust the energy out number, which was showing at 118kW

Bearing in mind the above note about kW and kWh, I would be seriously alarmed if you property was running at that power rating, which is roughly 40 3kW kettles all on the go at once. Over 24 hours, that will consume 2832 kWh of energy. At 25p/unit (or kWh), that is over £700 per day... 

Check exactly what that 118 figure is: units, and over what period. If you can do it, posting screenshots might help. Here's a rare example of one I took when I did have the app. It shows an 8 hour period from a single day, with the hourly kWh in ranging between 1 or 2 exactly, no decimal places because of the integer based counting:

@batalto might be able to provide further insights, if he hasn't fallen asleep again. 

@cathoderay I think the app has changed. I don't see any screens like yours. It's now Midea Smart Home.

Here are screenshots of Nov 1st to Nov 3rd. You can see that the electricity consumption is crazily high. Doesn't even seem to over-estimate consistently on electricity used. One day it's 5x the next 1.7 times.

Nov 1st full load consumption was 38.5 kWh and the normal daily use without heating and DHW is 13-14 kWh. Nov 2nd was 50.1 kWh and Nov 3rd was 26.5 kWh. My estimations for last 3 days for heating are  . Smart Home reckons 76, 81 and 40 just for Heating. Energy out at 119, 142 and 53. No idea what is going on. Might have to just do manual readings.

@pash44pump - oh dear, it looks like they've managed to take a bad app and made it even worse!

I agree the data does not appear to make much sense. For comparison, for the three days your data cover my data (mean OAT / kWh in / kWh out / COP) for both space and DHW heating are:

1 Nov    7.0 / 17 / 87 / 5.1

2 Nov    5.9 / 29 / 124 / 4.3

3 Nov   14.8 / 13 / 75 / 5.7 

In contrast, your kWh in / kWh out (as reported by the app) and COP (as calculated by me) for just space heating are

1 Nov    76 / 119 / 1.6     (when full load kWh in was 39)

2 Nov    81 / 142 / 1.8    (when full load kWh in was 50)

3 Nov    40 / 53 / 1.3      (when full load kWh in was 27)

Clearly something is very wrong! I can't even begin to make sense of it!

I think you have to do what I did, forget about the Midea app, because it is cr@p. A pity, they might have improved it, and it might have given you the sense check I hoped it would, but it seems to be the opposite, they have made it even more unintelligible.

That unfortunately means as you say manual data collection for now, very tedious and boring, but definitely better than nothing, so worth doing, until such time as you set up automatic monitoring

@pash44pump I found the midea smart home app really unreliable as well. It then completely stopped connecting, and I gave up with it.

I've got another thread running about our control set up and I've now added a bit of extra monitoring. In essence I'm using the modbus registers which record the cumulative energy consumption and output in kWh. This is then linked to home assistant, and HA has a really handy energy dashboard which can track the change, and would give you something like this (you can change the calendar icon at the top to show specific days, last week, last month etc):

I've also got combined COP for last 24hr period, using the helpers feature in HA and a bit of help from ChatGBT to set them up- this is displayed on a separate dashboard in gauge form. I'll probably update my main thread at some point. You obviously have the energy metering menu on the actual control panel which also takes it a step further and separates heating and DHW. I have been trying to set up some additional HA helpers to then plot COP hourly in some form of bar chart showing last 24hrs (much like Cathoderay has I think) but haven't quite managed to get that to work yet.

@benson I have to Shelly devices to measure the power usage of the indoor and outdoor unit and created virtual energy meters in Home Assistent for heating, dhw and defrosting. And then when the heat pump state is for example “DHW”, I update that virtual energy meters with the state op the 2 real energy meters.

That way I can perfectly see what amount of electricity  is used for each state.

@pash44pump The kWh energy usage data from the heat pump self is indeed rubbish, although I have read on this forum that the power output data seems to be quite good.

@mosibi yes I am interested in potentally evolving my setup along those lines for better accuracy. Haven't quite got my head around how they'd be installed. What ones do you have- have you got a link?

I've got the tesla gateway and app providing our overall usage for the house so the midea consumption data doesn't look to far out from what I can see.

Posted by: @benson

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What ones do you have- have you got a link?

I have two Shelly 1PM plus (discontinued and replaced by Shelly 1PM Gen3), which is working perfect, but if I have to start over I would have chosen the Shelly Pro 1PM for the simple reason that in my opinion it is nicer to have this metering all in a central location.

@mosibi — I, and I suspect others, am interested to know what the Shelley Pro 1PM offers over and above a standard modbus enabled energy meter like the Eastron SDM120M (prices vary, but typically a bit less than the Shelley Pro 1PM). The Shelley web page for the Pro 1PM talks about power metering but so far as I can see does not explain how it does that, or what the actual output from the Pro 1PM is. If it really is a power meter (kW), then how does it measure energy (kWh)?

Posted by: @cathoderay

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If it really is a power meter (kW), then how does it measure energy (kWh)?

I have a couple of Shelley devices, brilliant little bits of kit.  I can't comment on the particular one you identify but I would say that, if it claims to do what you want, it will.

Posted by: @jamespa

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Energy is just power x time

I know! What I was trying to get at here was clarification, both about what a Shelley can do, and yet again the difference between power and energy which still get regularly confused. The meter I mentioned is an energy meter, and it's display shows (cumulative) kWh (which is also available over modbus):

I'm asking what is the equivalent data/display from a Shelley so called 'integrated power meter', given that what we actually want to measure and record is energy use over time (kWh use per hour/day/whatever).

Agreed, @cathoderay.

In fairness, Shelly are pretty precise in their claims and, as such, also provide a range of energy meters alongside their power meters. The only distinction I can see between their offerings and the Eastron you mentioned is that Shelly don't seem to provide a modbus version. Other than that, like @jamespa, I have no concerns about recommending Shelly kit for doing what it says on the tin.