According to Cnet, Apple has received a patent from the US Patent and Trademark Office for solar powered electronics.
The patent is for a system for using a solar panel to charge a variety of portable devices, including notebooks, tablets and phones. The main thrust is around converting the power from a solar panel, which could be embedded or removable, so as to be useable by the electronic devices to recharge batteries.
Patently Apple (a web site entirely devoted to Apple patents, would you believe) has lots of detail about the device and points out that it’s Apple's fourth solar powered patent.
It looks like this is a theme for device manufacturers, although it’s not new. Vodafone Essar, the Indian subsidiary of Vodafone, launched a solar-charging handset in India last year. Cnet reports that there are already a number of third-party solar chargers designed for Apple equipment, although ‘Solar charger makers say that Apple products are particularly demanding in terms of the quality of power needed to effectively use solar panels’.