A Raspberry Pi photovoltaic monitoring solution

A friend of mine had a photovoltaic system (consisting of 14 solar panels) installed on his rooftop last year. As I was looking for another raspberry pi project I convinced him I would setup a reliable monitoring solution that will lead him to an access to the data in real-time data. The current setup comes with an inverter by the company Kostal.

Kostal Piko 5. 5 Inverter

The Kostal Piko 5.5 runs an internal web server showing statistics like current power, daily energy, total energy plus specific information for each string. However, the visual layout of the the web page and the bundled software look like they were designed in the late 90s and development has been abandoned:

Kostal Piko 5.5 Web Interface

The power inverter itself logs data at either a 15 minutes interval for about 100 days or at an hour interval for about 400 days. At the current setting the 15 minutes interval has been selected. Furthermore my friend took notes irregularly from the built-in liquid-crystal display.

The final plan is now set. A Raspberry Pi would fetch data from the inverter, store it in a database and a web application would render the results to a browser:

SolarPi SetUp

The project is live at http://solarpi.tafkas.net

  • NoGi

    I’m looking at doing something similar, what software did you use on the pi?

    • I am collecting the photovoltaic data using a python script and the pikopy library. The meter data is read also by a python script. The website is powered by a flask application. I will publish an article about it soon.

  • Alex Ellis

    Parts of your temperature logging system are very similar to my ‘PI Dashboard’ where I have PIs placed around the city and my home logging temperature data and the like. http://ucloud.ae24.space/

    I would like to have more nodes that just run on battery power and a simple Arduino ideally like you have. PIs are too heavy weight for one-per-room.

  • Fritz

    very good programm, is it avail. for SMA inverter, too
    Question sent from Fritz: E-Mail fritz3108@web.de

  • Walter

    Hi there,
    I’m really a newbie in python programming. I tried to find out how to setup this cool application but I don’t know where to start.
    Where can I find the config-files I need to edit for my environment? – And what steps do I have to make to get it running. Thanks for your help!

    by the way: I found out that with my version of flask I had to edit the file manage.py
    I had to change flask.ext.script to flask_script and flask.ext.migrate to flask_migrate

    Cheers Walter

  • Günter

    Hallo Tafkas,
    ich habe versucht dein Projekt auf meinem Raspi zu installieren. Jedoch fehlt mir die Erfahrung und leider auch die Zeit mich in die Programmiersprache vom Raspi einzuarbeiten. Da ich die Auswertung die du über die Abfragen realisiert hast echt super finde, möchte ich dir die Frage stellen, ob es nicht möglich ist, ein SD Karten Image online zu stellen, so das ich (wir) als user nur noch Anpassungen für IP & Passwort zu machen brauchen…Ich weiss, das ist die Sofa Methode, aber ich denke für dich ist es machbar und für uns ist es eine tolle Vereinfachung. Danke dir soweit.

    • Markus

      Ich wäre auch dafür !