If you use solar to charge your robot, it should have about 5-6 hours of runtime. In ideal conditions, you only need roughly 4 hours of direct sunlight. But as it’s dependent on the sun, much of that depends on time of year, day, sky conditions, pool shade, etc. That number can fluctuate. The Skimdevil also comes with a wall charger in the event your pool is located in a shady spot. But, many of our customers never end up using their AC/DC charger to power up their Skimdevil pool robots.