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Domoticz thermal energy kWh, thermal energy meter
Posted: Saturday 20 December 2025 17:47
by geoterm
Hello, could someone help? I need to measure and count the amount of thermal energy produced by a kW heat pump. How it do ? Is there such a device or do I need a script?
Re: Domoticz thermal energy kWh, thermal energy meter
Posted: Saturday 20 December 2025 20:22
by waltervl
What unit of measure do you need? Joules?
Re: Domoticz thermal energy kWh, thermal energy meter
Posted: Sunday 21 December 2025 9:01
by BartSr
Trying to calculate COP of heatpump?
Re: Domoticz thermal energy kWh, thermal energy meter
Posted: Sunday 21 December 2025 13:00
by geoterm
BartSr wrote: Sunday 21 December 2025 9:01
Trying to calculate COP of heatpump?
Yes of course, I have calculated cop, that's not a problem.
Re: Domoticz thermal energy kWh, thermal energy meter
Posted: Sunday 21 December 2025 13:02
by geoterm
waltervl wrote: Saturday 20 December 2025 20:22
What unit of measure do you need? Joules?
Best in kWh.
Re: Domoticz thermal energy kWh, thermal energy meter
Posted: Sunday 21 December 2025 14:55
by waltervl
geoterm wrote: Sunday 21 December 2025 13:02
waltervl wrote: Saturday 20 December 2025 20:22
What unit of measure do you need? Joules?
Best in kWh.
Then you can use a normal energy/electricity counter device. But your integration needs to supply the value, else you need to calculate it yourself with eg a dzvents script.
Re: Domoticz thermal energy kWh, thermal energy meter
Posted: Sunday 21 December 2025 15:38
by geoterm
Exactly, I need a script to calculate this. Maybe someone already has one like this and is willing to share.
Re: Domoticz thermal energy kWh, thermal energy meter
Posted: Sunday 21 December 2025 16:23
by HvdW
Easiest is to ask AI to write the script. AI has no problem writing dzVents.
BTW Can you share how to write your beatiful Dashboard?
Re: Domoticz thermal energy kWh, thermal energy meter
Posted: Sunday 21 December 2025 16:26
by waltervl
You can try to ask AI but be aware it creates also still a lot of rubbish, examples enough here on the forum.
But you first have to think about the values you need to calculate the energy in kwh. What iuput do you have and what should be the formula to calculate the desired energy....
Re: Domoticz thermal energy kWh, thermal energy meter
Posted: Sunday 21 December 2025 16:31
by geoterm
I don't want AI because nothing can replace a human in this regard.
The input data is: device operating time and heat pump power Qw. W [kWh] = P [kW] * t [h]
Re: Domoticz thermal energy kWh, thermal energy meter
Posted: Sunday 21 December 2025 16:33
by waltervl
So what are the Domoticz devices that have these values for P and t?
And when you have only P you can use an Electricity (Instant and counter) device that can calculate E kWh from P Watt values when supplied.
Re: Domoticz thermal energy kWh, thermal energy meter
Posted: Sunday 21 December 2025 16:40
by BartSr
For yr calculation you need:
Measure device for E-input
Temp measure device inlet water
Temp measure device outlet water
Waterflow measure device.
All available?
Re: Domoticz thermal energy kWh, thermal energy meter
Posted: Sunday 21 December 2025 16:48
by geoterm
ok
I'm working
Re: Domoticz thermal energy kWh, thermal energy meter
Posted: Sunday 21 December 2025 17:04
by RonkA
So correct me if i'm wrong but you want to take Retour to well temperature ( 22.31 C) minus From well temperature (20.5 C) what gives Delta-temperature (dT) of 1.81 C right now.
The flowrate (m) is now zero L/minute but in the calculation you need L/second so divide by 60.
You don't specify the liquid what is used in the well loop so that is a problem to make the right calculation, for now i assume The specific heat capacity (cp) of normal water what is 4180 J/liter.
So the thermal energy calculation (Q) would be now: Q=(m/60)*cp*dT --> Q=(0/60)*4180*1.81 --> Q=0 Watt
I don't know the normal flowrate but lets say it is 10 L/minute this would give Q= (10/60)*4180*1.81 = 1261 Watt
Re: Domoticz thermal energy kWh, thermal energy meter
Posted: Sunday 21 December 2025 17:05
by geoterm
I'm not an automation expert, it's my hobby, I'm just getting started.
Re: Domoticz thermal energy kWh, thermal energy meter
Posted: Sunday 21 December 2025 17:10
by geoterm
HvdW wrote: Sunday 21 December 2025 16:23
Easiest is to ask AI to write the script. AI has no problem writing dzVents.
BTW Can you share how to write your beatiful Dashboard?
Made in autocad without AI
.
Re: Domoticz thermal energy kWh, thermal energy meter
Posted: Sunday 21 December 2025 17:42
by geoterm
I'm testing to see if I've added the correct device, and then after a day of work, to see if it's counting correctly. But it looks good. Thanks.
I still have a few questions or missing information in my smart home.
Re: Domoticz thermal energy kWh, thermal energy meter
Posted: Sunday 21 December 2025 17:46
by geoterm
RonkA wrote: Sunday 21 December 2025 17:04
So correct me if i'm wrong but you want to take Retour to well temperature ( 22.31 C) minus From well temperature (20.5 C) what gives Delta-temperature (dT) of 1.81 C right now.
The flowrate (m) is now zero L/minute but in the calculation you need L/second so divide by 60.
You don't specify the liquid what is used in the well loop so that is a problem to make the right calculation, for now i assume The specific heat capacity (cp) of normal water what is 4180 J/liter.
So the thermal energy calculation (Q) would be now: Q=(m/60)*cp*dT --> Q=(0/60)*4180*1.81 --> Q=0 Watt
I don't know the normal flowrate but lets say it is 10 L/minute this would give Q= (10/60)*4180*1.81 = 1261 Watt
I took a screenshot so the delta calculation—you're right—is based on the time interval. Before the correct calculation was made, the previous temperatures were visible.
Re: Domoticz thermal energy kWh, thermal energy meter
Posted: Sunday 21 December 2025 17:52
by geoterm
HvdW wrote: Sunday 21 December 2025 16:23
Easiest is to ask AI to write the script. AI has no problem writing dzVents.
BTW Can you share how to write your beatiful Dashboard?
Please, if you want.
Re: Domoticz thermal energy kWh, thermal energy meter
Posted: Sunday 21 December 2025 17:54
by geoterm
This is a diagram of an air-source heat pump. To the left of the wall is the outdoor air-source unit, and to the right is the building system with a glycol heat exchanger.