Since 2013 we have a photovoltaic system with 5.2kWp on our houses roof. In combination with the SMA inverter it was not a big deal to monitor the PV output. There is a webpage of SMA where you can see the outputs for every day, month and year. The inverter itself sends the data to the SMA servers.
Now I wanted to montitor and visualize all the data by myself. And not only the PV output but also the energy consumption. Which means additionally power import and export. To get these data I installed the SMA Energy Meter. With this piece of hardware you are able to monitor the energy flow for every phase in your house. The measured values are then broadcasted, or better multicasted, to your local lan.
I wrote a little programm to receive these multicasts, extract the interesting values and save them in a SQLite database. Additionally I used the SBFSpot tool to get the current PV output from the inverter. The current PV output will also be saved in a SQLite DB. A small webpage collect all the data from the database and visualize them with Highcharts.
Here are some screenshots of the beta version. It also runs quite fast on a Rasperry Pi 2, but currently I use it on Ubuntu 14.04 LTS.