The environment

http://ed.ted.com/on/2Yy019iv

http://iteslj.org/questions/environment.html

http://www.youtube.com/watch?v=7OAcv7k8Qc0&feature=related

http://www.breakingnewsenglish.com/0807/080714-solar_energy.html

http://www.headsupenglish.com/minilessons/ecotours.pdf

http://www.breakingnewsenglish.com/0712/071211-wind_farms.html