"Please consider the environment before printing this email." This quote is familiar to e-mail users of a pervasive environmental awareness. Bills and bank statements now come with paper-less options, and newspapers are being e

schewed for Web site visits. But how effective for saving resources are these measures? Don Carli of PBS.org collected numbers from various sources to answer this question.

As Carli notes, consumers are given the choice between digital media or traditional paper, aimed to "confront consumers with a false dilemma and present a forced choice that may have unintended consequences. The false dilemma is: 'By using paper to print your email or by receiving paper bills you are knowingly degrading the environment, destroying forests and/or killing trees.'The forced choice is: 'Eliminate your use of paper or feel like a guilty hypocrite.'"

But does the tradeoff actually help the environment? Carli suggests that digital media can be more destructive to the environment, including "trees, bees, rivers and forests in the United States than paper-making or printing(...)"

Digital media technology sources energy from coal power plants which add to global warming. Greenpeace projects that data centers will demand more electricity than France, Brazil, Canada, and Germany combined by 2020. Additionally, the coal mining process contributes to deforestation, biodiversity loss, and headwater stream pollution in the US.

The deforestation of over 600 square miles of US forest has been connected to the current framework for computers, cellular networks and data centers. The push for cloud computing has intensified this workload as more energy is needed for an always-on global network.

Electricity used by data centers doubled from 2000 to 2006 to 60 billion kilowatt hours per year, according to the US Department of Energy. This amount equals that used by 559,608 homes in one year, and could double again by 2011. Carli presents more data on coal-power and other unseen impacts of digital media in his article.