For the first time, smartphone shipments have reached 1 billion. That probably means a lot of calling, texting, and app use. It also means a lot of phones being plugged into the grid and charging.A new study by analyst Juniper Research found that smartphone charging could soon be a massive generator of carbon dioxide, which is one of the greenhouse gases thought to cause global warming. According to the study, greenhouse gas emissions from mobile devices will more than double within five years.
http://www.cnet.com/au/news/smartphone-charging-spews-out-megatons-of-greenhouse-gases/