I have a consumer motion-triggered camera that is armed 24/7 and records for 30 seconds after each trigger. It has WiFi and serves playback itself, as well as of course video encoding. It's probably running Linux though i haven't verified.

It runs off a 25cm square solar panel screwed to a wall that only receives direct illumination for 5 hours a day, and is not in any way optimised beyond 'that looks roughly like it's pointing at the sun'.

Works great!