After collecting some photovoltaic data using PikoPy and a some readings from the residential meter it was time to put everything together. The data is collected by a couple of scripts triggered by a cronjob every five minutes.
$ crontab -l */5 * * * * python /home/solarpi/kostal_piko.py */5 * * * * python /home/solarpi/collect_meter.py */15 * * * * python /home/solarpi/collect_weather.py The results are then written into a SQLite database.
The first step of my plan, building a Raspberry Pi based photovoltaic monitoring solution, is finished. I created a python package that works with the Kostal Piko 5.5 inverter (and theoretically should work with other Kostal inverters as well) and offers a clean interface for accessing the data:
import pikopy #create a new piko instance p = Piko('host', 'username', 'password') #get current power print p.get_current_power() #get voltage from string 1 print p.
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.
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.
