While playing around with the solar panels I noticed that the animations don't always represent the current state of the machine. In the screenshot below the panels are working at full power but not animated as such. I experimented with reloading the save and noticed that the condition the solar panel is loaded in as will be the one displayed permanently. So loading the save while production is high will cause the animations to keep playing even when there is no light and loading while the doors are closed will cause the inactive animation to play regardless of state. Upon building the solarpanel it will also be stuck in one of the two animations until the save is reloaded.
Steps to Reproduce
Build a solarpanel, play around with loading your save when light is available or not.
This issue has not been confirmed by a developer yet.