Best approach using powercalc in calculating consumption of central heating?

[vahaldor]

I am trying to figure out what would be the best approach to calculate the consumption in a time of my smart valves. Each room has one smart valve from Netatmo that provides the attribute 'heat request' with variables from 0 to 100. This number says how much is the valve open. I am quite aware that this won't lead to precise kWh but at least a graph showing the comparison of how much we are heating the apartment between weeks and months would be nice. Any ideas?

[bramstroker]

You are using electricity for heating? I don't understand exactly what you are trying to achieve.

[vahaldor]

I have central city heating with warm water. The same water goes to taps and radiators. No electricity heating. I pay for m3 of heated water.

I know how much my valves are open (1-100%) for a defined period of time. And I would love to see at least that December used 5x more water than November or per day. I can try to heat to 20C in one day when outside is 5C and see how much it was. The unit probably has to be a virtual unit for comparison only as there's no way to know how much kW I consumber. Cubic meters also do not matter as the same water meter meters warm water to the bathroom and to heaters as well.

[wigster]

Well, the city heat used here is measured by comparing the temperature of the water coming into my apartment with that leaving times the flow volume -- you can see how much energy was lost to heat the rooms.

The only proxy you will get by looking at the valves is the total % valves open (I track that for fun), but this isn't a good guide to the energy use -- the input temp varies because it goes through some other apartments first. Then for a fixed flow, the heat loss is larger when the room temperature of colder. You will lose this information and I suspect it's the more important part.

[vahaldor]

I think that the best way for me is to follow the numbers on the analog meter. There are some methods how to OCR it and keep an eye on it... translating that into energy seems to be a bit overkill for our self-control.