I just came back from a 12 day river trip. I was under direct sunlight all but one afternoon. It took two full days of full sunlight to charge the battery. Something to be aware off if you're in less than direct sunlight. The Solio was very finicky on charging. It did work once to charge my ipod and cell phone. Later in the trip it wouldn't do a thing, even though it had a full charge. I was grateful for the two charges it gave me. I was upset and frustrated when it failed, especially once I relied on it. I'm going to work with it now that I'm home and see if it a defective model or if it's just unreliable. It did work for awhile, but if you're going to depend on it, be careful.