How to monitor my consumption?

Questions
#1

Hi Guys,

This is my current setup.
I have a SMA Tripower 5.0 inverter with Webconnect, connected with a Ethernet cable to my network.
Then I have a Raspberry Pi Running SBFspot, transmitting my SMA data to PVOutput every 5 minutes.
This works Great.

But I also want to measure my consumption now.
I live in Belgium and I don’t have a smart meter from the electricity company yet, who can do it for you.
Still have the old analog meter, and intend too keep it as long as possible (Belgian people will know why).

So I need a way to measure my consumption with an external meter.
I have an ‘old’ Smappee laying around, but its not able to measure my PV pannels, only the energy I take from the supplier.
I hooked it on to see what happens and during the day it reports my consumption minus the power my pannels are generating, so that’s not good.

The tricky part is that my electricity cable coming in from the company is a 3-phase cable, and my inverter is also a 3 phase inverter.
So if I would go the smappee-like way, I would need 6 clamps to be able to configure it correctly, correct me if I’m wrong.
Have not found anything like that online.

I could just buy a SMA home manager 2.0, which I think would solve my problem but it too expensive (600 - 700 euro’s).

What would be the best and most inexpensive way to go here?

Help would be much appreciated as I’ve spend many hours online looking for a inexpensive solution to this.

#2

I’d be looking at one of the options where the CT sensor goes onto your home load circuit-breakers and measures the house consumption directly. I use an Efergy system (https://efergy.com/engage/), the base uploads to the Efergy cloud, and PVO can automatically query the Efergy cloud, so you don’t need any in-house server system to get the consumption into PVO.

You might be able to use the Smappee, hooked into your consumption bus rather than the solar or grid cables. PVO has integration with Smappee also - https://pvoutput.org/help.html#autoupload-smappee

With PVO you can have your consumption measured by one system (your Smappee, Efergy, whatever) and the generation measured by a different system (your SMA SBFspot), and it will stitch them together - and calculate your ‘grid consumption’ from the difference between generation and house load consumption.

#3

I use an Iotawatt on my USA split phase system. You would only need 3 current transformers for the incoming phase leads. This device can measure forward and backward current flow, and has PV Out reporting built in. You would set it up it to report ONLY your consumption. (Forward minus reverse power at the mains).
You could also add additional current transformers for the solar. The unit can handle up to ( i think) 14 total current transformers.

You can go to their forums and read up on discussions about using it for 3 phase applications.

#4

Forward - Reverse gives you net power/energy, not consumption. The general formula is Net=Consumption-PV so Consumption=Net+PV. (Sign convention is that positive Net=import to home from grid and negative Net = export to grid) To measure consumption, you need to measure both the net and solar, so for a three phase system, you need six current transformers.

PVOutput does allow the upload of Net and will then calculate Consumption as long as you are uploading PV data from your inverter.

#5

Thanks for all the great feedback.

I contacted Smappee to get access to their API and they ask a monthly fee for it … not what I hoped.
So I’ve been looking into Iotawatt, looks like a great system for what I need.

Ordere an IoTaWatt, hope that arrives next week