quite a reversal from January 2012 when Nokia shot down the idea of using the sun as a green and cheap way to power up smartphones. Back then, we told you that Nokia had even built five prototypes which were given to five testers who staked out positions throughout the globe. The effectiveness of the process depended greatly on what part of the world the phone was being tested in. For example, in Kenya, where the sun is out all year, the solar recharging worked the best. On the other hand, at the Arctic Circle, the low angle of the sun forced the tester to chase sunlight as it moved around the house every day.
Trying to decipher the caption, some have theorized that Nokia is merely making a comment on the yellow color of the unnamed phone. Or perhaps the OEM is just looking forward to the summer. If Nokia is indeed working on a phone that uses solar charging, it could help sell its smartphones to those who are considered "green". How important would solar charging be to you in deciding which phone to buy?
source: Nokia via WPCentral