Samsung, LG and ZTE all introduced solar-charging mobiles at this year's World Mobile Congress as the wireless industry is tapping into the green movement.
Samsung claims its Blue Earth is the first solar-powered full-touchscreen phone made partly from - get this - plastic bottles.
Samsung's head of mobile communications division, J.K. Shin, said the phone was named Blue Earth - and not green - because from outer space the planet appeared blue.
The phone will be released in the second half of the year.
LG Electronic's solar-powered handset unveiled last week has a solar panel embedded on the phone's battery back cover to harness the power of the sun: 10 minutes in the sun provides enough power for a three-minute call, the company said.
LG is also touting its ecofriendly packaging, using recycled materials and soy-based inks.
The ecofriendly phone will be released in Europe at the end of the year.
Chinese manufacturer ZTE's solar-powered device was the only one specifically aimed at the developing market, with a price under $40.
It is set to launch at the end of May.
The battery cover includes a solar panel to recharge the battery: One hour in the sun for five minutes of use.
