Can one phone use as much energy as two refrigerators?

Summary:The energy draw of smartphones and tablets are dwarfing what we traditionally think of as energy hogs in the home, according to a new study.

The energy draw of smartphones and tablets are dwarfing what we traditionally think of as energy hogs in the home, according to a new study. And all those data centers, wireless base stations, and wired networks are largely powered by coal. IEEE Spectrum reports.

A phone -- and other information-communications technologies (ICT) -- plugged into the wall draws a negligible amount of energy. But:

Add in the amount of electricity it takes to move data across networks to deliver a total of, say, an hour of video to your smart phone or tablet each week, and over a year it adds up to more power than two new Energy Star refrigerators consume in a year.

And while electronics are becoming more and more efficient, their efficiency doesn’t offset their explosion around the world.

Some highlights:

  • The global ICT ecosystem uses about 1500 terawatt-hours of electricity annually, which is equal to the electricity used by Japan and Germany combined. That figure will increase as cloud architecture overtakes wired networks.
  • This growth is also driven by “revolutions in everything from healthcare to cars, and from factories to farms.”
  • A 50-megawatt enterprise data center in Iowa that gets 70 percent of its energy from coal and 25 percent from wind will cost $350 million less to run over its lifetime compared with one in California, with no coal in its energy mix.
  • However, environmental regulations could eliminate the favored position coal enjoys because of its low cost. For instance, U.S. President Barack Obama has called for existing coal-fired power plants to meet more stringent greenhouse gas emissions standards.
  • In India (the second largest mobile market after China), 75 percent of rural and 33 percent of urban cellphone base stations will need to run on alternative energy by 2020.

Some work is already underway. By 2015, the GreenTouch Consortium plans to make ICT networks 1000 times as efficient as those that were in operation in 2010.

The study [pdf] was sponsored by the U.S. National Mining Association and the American Coalition for Clean Coal Electricity.

[IEEE Spectrum]

Image: Stevan Sheets via Flickr

This post was originally published on

Topics: Innovation


Janet Fang has written for Nature, Discover and the Point Reyes Light. She is currently a lab technician at Lamont-Doherty Earth Observatory. She holds degrees from the University of California, Berkeley and Columbia University. She is based in New York. Follow her on Twitter.

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