Trends come and go but doing things for the environment never goes out of style. Sony Ericsson knows this and is pushing toward greener features within the next two years and is set to release two new handsets putting the plan into practice.

Calling them the Elm and Hazel, these new phones are part of Sony Ericsson's "GreenHeart" initiative, the project to make handsets from recycled plastics and free from hazardous chemicals to help reduce CO2 emissions.

Each comes with a low-power charger, the WalkMate application that lets users compare the steps they take with the equivalent journey by car and a "Green" calculator to show how much CO2 they save when walking.

They also feature "Noise Shield" technology for better voice quality, a 5.0-megapixel camera, FM radio and music player and Wi-Fi and Bluetooth connectivity.

The Elm and Hazel handsets will be available in the first and second quarters of 2010, respectively.