Greenpeace said about 500,000 Facebook users have urged the world's largest online social network to abandon plans to buy electricity from a coal-based energy company for its new data center in the U.S.
Greenpeace International Executive Director Kumi Naidoo sent a letter Wednesday to Facebook founder Mark Zuckerberg warning that the company risked its reputation and financial health if it ignored the environmental impacts of its actions.
"Facebook is really out of step with the trend" among information technology companies, Naidoo told The Associated Press by phone.
But Facebook says it is committed to environmental responsibility and that the data center in the state of Oregon is "one of the most efficient in the world."
The Amsterdam-based environmental group started a Facebook campaign in February after the company announced plans to build the center in Oregon.
Last week, Greenpeace-sponsored groups urging Facebook to use 100 percent renewable energy passed a collective 500,000 members -- a small fraction of Facebook's more than 500 million users worldwide.
Naidoo said Facebook "had a choice" as to where to locate the data center and made an "active choice to lean in the direction of dirty coal."
But Facebook says Greenpeace is offering a simplistic explanation of how energy grids work, and the company choose the location of its data center because it could be energy efficient. To say the Facebook "chose coal" is inaccurate, said spokesman Barry Schnitt.
The high desert climate of Prineville, Ore., is dry and cools down at night, which Schnitt said has allowed Facebook's data center to operate without energy-hungry "chillers," used to cool the buildings so that the servers inside don't overheat.
Naidoo said his organization singled out Facebook because of its reach across the globe, especially among the young. Information-technology companies, including titans such as Microsoft, contribute an estimated 2 percent of human-made carbon emissions, about the same as the aviation industry. But the IT sector is growing fast. Greenpeace cite studies saying the industry has the capability to reduce its emissions 15 percent by 2020.
Greenpeace says the utility PacifiCorp, which powers the data center, uses 83 percent coal in its energy mix. But PacifiCorp spokesman Tom Gauntt said this number is actually 58 percent. The rest is natural gas at about 20 percent and hydro and renewable energy at about 10 percent each.
Burning coal for power is one of the largest sources of carbon accumulating in the atmosphere.