Monitoring Solar Panel Output

We recently installed 3kW of solar panels on our house, and being a data nerd I was keen to monitor their performance.

Our system is a Fronius Galvo 3.0-1 inverter paired with 12x 260W REC panels.

From a monitoring perspective, the Galvo 3.0-1 seems to have been a good choice. It comes with wifi, and the installer connected it to our network on installation day. From there, I was able to connect to a web interface and poke around.

I clicked a button to upgrade the firmware to 3.3.5-22, which included a new “Push Service” feature. This pings a remote HTTP or FTP server at regular intervals with the latest output data.

Following instructions from pvoutput, I configured the inverter to update my profile every 5 minutes, leading to charts like this:

chart has a public API, so there’s also a few android/iOS apps available. None are perfect, but my current favourite is Oxley Solar. Its intra-day charts look like this:


There’s also a well documented HTTP JSON API available on the inverter. I’m not actively using it, but it’s straight forward:

curl ""
        "Head" : {
                "RequestArguments" : {
                        "DataCollection" : "CommonInverterData",
                        "DeviceClass" : "Inverter",
                        "DeviceId" : "1",
                        "Scope" : "Device"
                "Status" : {
                        "Code" : 0,
                        "Reason" : "",
                        "UserMessage" : ""
                "Timestamp" : "2015-03-03T15:30:00+11:00"
        "Body" : {...}