The solar inverter went to generating basically no power for a few minutes, and I went out to see it resetting itself. It did it again, a short while later. I called the solar company, and somebody's going to call me back.
The light blue line is the solar generation, and you can see at around 11:20 and 12:15 it goes to 0. Great - I believe the inverter should still be under warranty, but I haven't dug out the paperwork to see yet.