The Internet may not consume nearly as much environmentally unfriendly fossil fuel as airplanes or automobiles, but the growth of cloud-based services offered by Apple, Netflix and others is forcing data centers to provide greater speed and more storage capacity. All of this size and speed comes at a price. Data centers generate a lot of heat that has to be whisked away by power-hungry air- and liquid-cooling systems to keep the Internet's engines from burning themselves out.

Efforts to combat this growing power consumption have been lukewarm, argues Diego Reforgiato Recupero, a computer scientist and electrical engineer at the University of Catania in Italy. In the March 29 Science, Reforgiato Recupero shows that Internet traffic volume doubles every three years, yet this increase in usage has not been matched by a similar increase in network energy efficiency.

To avoid adding more greenhouse gases into the atmosphere, these data centers need new approaches, Reforgiato Recupero says. He points to two in particular. One is smart standby, which places unused portions of computer server and networking equipment into very low power states. Another—dynamic frequency scaling—allows computer central processing unit usage to be throttled back on the fly when data traffic on a network is light.