Goal Zero solar panels do not hold a charge; they produce power when exposed to sunlight. For the best charging experience, pair with a Flip 12, 24, or 36 power bank to keep devices charged on the go. Simply plug the Flip into the panel's built-in charging dock to charge the battery from sun while hiking or away from camp. Then, use the charged Flip to charge your electronics when the sun goes down. Devices can be charged directly by a sunlit Nomad 5 as well.