A Beautiful Mind

Continue our Solar Power Adventure…

Last week David spent his vacation writing a C software package called fslurp at SourceForge, to “read and display data from Fronius IG and IG Plus inverters, using a serial port to talk with the Fronius Interface Easy Card.” Because now we have a way to read our inverter’s beautiful mind, it’s time to start collecting data and do something about it!

First I wrote a tiny Python script to clean up the dataset generated by David’s fslurp. Next I loaded the cleaned dataset to R for the data visualization step. However, things didn’t go as well as I had in mind; the plotted graph looked strange — each reading was a short horizontal line instead of a circle.

After investigating the problem for a while, I realized that I got tripped over by the infamous Factor object. Fortunately, plenty of experienced R users have already solved this problem and posted their solutions along with detailed explanations online. Even better, William Revelle actually implemented the same solar power plotting project back in Feb. 2006! While he had 38 months of data, I just had 1 day to play with. But, still!

Tomorrow I’ll need to add a little shell script to have the whole process automatically run at the end of the day. Frankly, it’s more interesting to have at least 1 year of data, so we can see the amount of power generated following the changes of season. But we’ll get there, and we’ll have a lot more data to track!

[10/27/2009 UPDATE] Yesterday I forgot to post the daily summary: