Nokia study finds solar charging cell phones "challenging"

It is one of the persisting dreams of cell phone design: to be able to charge your device with solar power. Unfortunately, a Nokia study has found that the dream is still a ways off and holds a number of challenges. The study was conducted over the past 6 months in a 5 different countries using a customized C1-02.
Two tests were done in the Arctic Circle, one in southern Sweden, one in Kenya and one sailing the Baltic Sea. This was done to get a good range of weather patterns. Of course, the major challenge for solar charging is a simple one: solar panels just aren't efficient enough yet. Kenya had the best results, which is no surprise, because there's no shortage of sunlight there. But, even when a phone was well positioned in the sun, it could only gather enough energy to keep the phone running, with almost nothing left over to actually use the device. When powered off, it would take about 12 hours to charge the phone, and not many places can get 12 hours of uninterrupted sunlight.
Of course, even beyond those issues, these tests were done with a dumbphone, which has very small battery needs compared to our new smartphones, so if solar charging can't even power a dumbphone properly, we still need solar panels to get a lot more efficient.