Facebook is getting some green love from Greenpeace.

The activist environmental organization declared victory in its nearly two-year campaign to pressure Facebook to reduce the environmental impact of its data centers. The social media giant’s data centers house a colossal arsenal of servers that supports the friendships and marketing campaigns of 800 million people across the globe.

Most of the electricity that powers Facebook’s data centers — and most other data centers — comes from coal-fired power plants. Greenpeace’s Facebook campaign, dubbed Unfriend Coal and centered on a Facebook page, gathered 700,000 supporters, according to the organization. The campaign also garnered a Guinness world record for most Facebook comments in a 24-hour period.

Greenpeace and Facebook issued a statement Thursday outlining a collaboration on clean and renewable energy. The agreement is short on quantifiable goals and encompasses several existing Facebook initiatives, principally the Open Compute Project. Facebook launched the industry coalition in April with the aim of sharing and promoting specifications for energy-efficient data centers.

Perhaps the most substantial commitment from Facebook is the company’s agreement to adopt a siting policy for new data centers that states a preference for access to clean and renewable energy. Facebook received an F on infrastructure siting in Greenpeace’s Clean Cloud Power Report Card.

The report card was issued as part of the organization’s April report: How dirty is your data? The report lambasted web-scale data center operators for chasing after cheap, dirty electricity. Apple took the brunt of Greenpeace’s ire, but Facebook was near the top of the offenders list. Of the 10 data center operators rated on the report card, Facebook was second to Apple in highest coal intensity for mix of power sources.

Facebook’s agreement with Greenpeace also calls for the company to pursue research into clean energy for data centers and to “engage in a dialog” with the company’s utility providers about increasing the supply of clean energy to Facebook’s data centers. Greenpeace and Facebook promised to work together to use social media to organize people around energy conservation and clean energy issues.

Facebook partnered with the Natural Resources Defense Council and energy use data provider Opower in October to use social media to raise consumer awareness about energy efficiency. Greenpeace pledged to support that effort, and to encourage companies to participate in the Open Compute Project.

The Open Compute Project’s formation coincided with the opening of Facebook’s energy-efficient Prineville, Oregon data center. Facebook also announced plans in October to build a massive data center near the Arctic Circle in Luleå, Sweden. Greenpeace reacted positively to the Open Compute Project and Swedish data center plans. Thursday’s announcement completes the thaw in the Greenpeace-Facebook relationship.

The question now: will Apple and its new CEO get jealous and try to win Greenpeace’s heart?