With a record number of viewers watching video streams of the presidential inauguration this week, it’s not hard to see why energy consumption of the Internet has doubled between 2000 and 2006. And it’s just going to consume more energy as greater numbers turn to the web for entertainment, news, communication and shopping and as Internet users demand faster broadband speeds.
But take a closer look at the numbers and we can see the Internet is actually getting more energy efficient. According to data from Jonathan Koomey, scientist with the Lawrence Berkeley National Laboratory, while Internet energy use doubled from 2000 to 2006, Internet traffic has far more than doubled during that period, and has ramped up by a factor of 20 to the 5th (or 3.2 million). The reason for the discrepancy is because network technologies have gotten consistently more energy efficient per unit of data transferred over the Internet.
In geek terms that’s called “energy intensity” — or the energy used to move a gigabyte of data across the network (kWh/GB). And between 2000 and 2006 the energy intensity of the Internet decreased by an order of magnitude, says Koomey.
|Internet Electricity Use (TWh/yr)||grew by 2.2|
|Low data traffic||grew by 22.5|
|High data traffic||grew by 22.9|
|Energy Intensity||grew by .1|
Source: Jonathan Koomey and Cody Taylor
Partly that’s because newer networking technologies are generally more efficient. Older technologies like dialup and traditional wireline connections use 3.56 kWh per GB. Newer technologies including fiber and power lines use .77 kWh/GB, while cable uses .72 kWh/GB and DSL sips a low .17 kWh/GB. These figures don’t include the power consumption of the end-device like a laptop or a cell phone. Also remember the measurement is energy per gigabyte of data, and newer networks also transmit significantly more data than older networks.
Cisco, the largest gear provider for the Internet, has been making its network more energy efficient for years as a way to offer hardware with lower energy bills for service provider customers, and Cisco touts its switches as the first to be designated by consultancy firm Miercom to be “Certified Green” for their efficient power draw and smart power management capabilities. Cisco is also working on other energy efficiency networking standards and says they are “fully committed to providing networking solutions that lead the industry in energy efficiency.”
Most importantly a substantial drop in the energy intensity of the Internet from more efficient hardware is a solid sign that continued installation of efficient hardware could deliver a web that could actually help reduce our overall carbon footprint by replacing other carbon-emission heavy actions, for example online shopping reduces the carbon emissions from driving a car to and from the store. While many are concentrating on the rising overall power consumption of the Internet, the Internet as a carbon-reducer is a real possibility if the hardware itself can get efficient enough. (Jonathan Koomey will be giving a talk at our Green:Net conference in San Francisco on March 24th).