The next time you watch "House of Cards" on Netflix, think about the impact you might be having on the environment.
As the Internet powers ever more services, from digital video to on-demand food delivery, energy use in data centers will rise. To reduce their impact on the environment, companies like Apple, Google and Facebook have taken big steps to power their operations with renewable energy sources like hydro, geothermal and solar.
But despite those efforts, the growth of streaming video from the likes of Netflix, Hulu and Google's YouTube presents a pesky challenge to the companies' efforts to go green, according to a report Tuesday from Greenpeace.
"The rapid transition to streaming video models, as well as tablets and other thin client devices that supplant on-device storage with the cloud, means more and more demand for data center capacity, which will require more energy to power," the report's authors wrote.
It might seem that online services, like video streaming, would reduce carbon footprint versus, say, driving to a movie theater. But by enabling much higher levels of consumption, the shift to digital video may actually be increasing the total amount of electricity consumed, and the associated pollution from electricity generation, the report said.
"Unless leading Internet companies find a way to leapfrog traditional, polluting sources of electricity, the convenience of streaming could cause us to increase our carbon footprint," wrote the authors of the report, "Clicking Green: A Guide to Building the Green Internet."
The report ranked companies efforts in the area of renewable energy, by looking at company supplied data on energy use, publicly available information, and other data center investments. Apple took top marks, partly due to its investments in solar and its level of transparency toward reducing its carbon and energy footprints for its data centers. Google and Facebook also scored highly, partly due to their lowered reliance on dirtier forms of energy like coal and natural gas.
The authors did not rank Netflix, YouTube or Hulu, but they did identify online video as by far the biggest driver of consumer Internet data. Streaming video services now make up more than 60 percent of consumer Internet traffic and are expected to be 76 percent of traffic by 2018, according to the Greenpeace report, citing data from Cisco.
YouTube owner Google has a long term goal of being 100 percent renewably powered, though it's currently only at 35 percent. In the Greenpeace ranking, Google achieved a clean energy index of 46 percent -- Apple got 100 percent -- which took into account Google's energy transparency and its specific renewable energy projects. Over the past year Google has signed three long-term contracts to buy clean energy from producers, the Greenpeace report said, adding to six previous contracts. The company has also advocated for policies that would reduce the U.S. dependence on coal and fossil fuels.
In addition to rising consumer data demands, the report's authors identified uncooperative utilities that rely on coal to generate power in data center hot spots like Virginia and North Carolina, as a barrier toward wider use of renewable energy.
In North Carolina, customers are not allowed to buy power from anyone other than Duke Energy, which gets only 2 percent of its electricity from renewable sources, according to Greenpeace. Google and other IT companies have supported a renewable energy tariff for large customers in North Carolina, the report said, but Google has not signed up for the program.