Update on the sunpowered server
TL;DR - go to data.cyplo.net
Some, rather long, time ago I've added a custom python-driven data acquisition and graphing to my sunpowered RaspberryPi installation on the balcony. Since then I've upgraded it to Raspi2 and ported the data thingy to influxdb + grafana. All 3 of those things I am very positively surprised by.
RaspberryPi2 - definitely worth the upgrade - it's a speed daemon now. Small caveat - I recommend installing raspbian from scratch, especially if you had some custom overclocking config, as these do not seem to be compatible between 1 and 2. Also RasPi2 needs a microsd card instead of full-sized one. As for the software - since everything went suprisingly smoothly this post is not much of a tutorial. Just go to influxdb and Grafana and go through the respective installation documentation. You need x86 64bit server to host this, so unfortunately no self-hosting on RaspberryPi - at least I wasn't able to compile the software there. I've changed the original python scripts slightly, to upload the data to influxdb instead of graphing directly via matplotlib. Then configured grafana to display some cool graphs and that was pretty much it - you can see the result at data.cyplo.net.
Right now I'm testing 2 different sizes of solar panels and batteries, hooked at the same time. The ADC is connected as it was before though, so a TODO is to add more measurements, to see how the individual panels' output change during the data and how does it affect each of the batteries.