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Have you used portable folding solar panels (5-20W) like Anker or GoalZero with much success? It seems like they would really only work well on a pack trip if you have a day off periodically to recharge equipment, otherwise I would think there's just not enough time to charge up your gear.

marked as duplicate by Ben Crowell, Rory Alsop Dec 3 '14 at 23:10

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