Here is a useful charging device that use just solar power to charge almost any device with a USB port. Simply unroll the three flexible solar panels and plug into your device, no battery packs to charge just a straight power boost. It will take about three hours of direct sunlight to fully charge the battery of an average Smartphone.
This is how the Folding USB Solar Cell will work;
The idea is simple. Put three small solar cells together in a nice enclosure that outputs to USB. Just unfold and plug in. A small package that is inexpensive and very useful. Combined, the solar cells put out 5W, or about 1 Amp of power at about 5 Volts, that outputs directly to a standard USB port. No special dongle or adaptor needed, just plug in any device that has a USB port on it. How does that translate into the “real world”? At full sunlight, you will charge up an iPhone in around three hours.
This is a project on Kickstarter, they needed $5,000 (£3,250) but so far, they have a massive $77,000 (£50,000) so it is safe to say that this is another successful crowd funded project.
Source: Brown Dog Gadgets