Solar Power Leashed, an article that describes how to use the Solcast API to predict the power output of an array of solar panels, has been published recently on Linux Magazine #268
I had a powerful solar array installed at home last September (you may check the article for the pictures!), so I naturally wanted to be able to predict the power yield I could expect day by day, so I could schedule my power consumption in advance. In other words: I wanted to be able to know if a given day is a good day to turn on the washing machine and the garden watering pumps, or if it would be wiser to wait for a day with a more favorable solar irradiation forecast.
The article includes a very handy Perl program that is capable of giving you a forecast which reaches up to 3 days in the future.
You may find the article in Linux Magazine #268.