I implemented base level monitoring for our solar installation several months ago and it is working well - having calibrated the AC adapter the figures that I am seeing for cumulative kWh closely match what our smart meter is recording for import and export.
We have recently added 10.5kWh of batteries supported by a separate AC-coupled inverter and I now want to monitor how these are working - our current arrangement does not allow me to do this. So I am looking for a bit of advice.
This picture shows our set-up:
The solar and battery inverters are in the garage, linked to the house via 30 metres of underground cable. The existing CTs in the meter box monitor the grid supply (CT1), the link to the garage (CT2) and consumption by the house (CT3); they are connected to an emoncms box in the house (on the wall in the office which is immediately behind the meter box).
I believe that in order to accurately capture the solar generation and battery charge/discharge information I will need to install 2 new CTs, shown as CT-x and CT-y in the picture.
I have a wired WiFi repeater in the garage so am looking to use MQTT to pass the data from the new monitoring in the garage to the existing emoncms system - the house acts like a Faraday cage (lots of foil insulation in the walls), so other RF solutions won’t work.
So my first question: Is there any small platform that can support 2 CTs and an AC voltage input with comms over WiFi?
If not, I am considering building something around an ESP32 or a Raspberry Pi Pico W - both of these support WiFi as standard and have multiple ADC inputs.
I would appreciate thoughts on the above.
Thanks, Martin