Social networking giant Facebook last week said it was already planning to expand its not-yet-completed data center in Prineville, Ore., and Greenpeace took the opportunity to yet again call the company out for not being greener.

In a note on the website, Facebook's director of site operations, Tom Furlong, said that the company is moving forward with a planned 160,000 square foot phase two of the facility. The current phase, which is expected to be completed by Spring 2011, will be 147,000 square feet.

"To meet the needs of our growing business, we have decided to go ahead with the second phase of the project, which was an option we put in place when we broke ground earlier this year," Furlong wrote. "The second phase should be finished by early 2012."

Facebook caused a bit of a stir when it announced the groundbreaking of the data center in January. Though the facility touted a number of green claims, including energy-efficient evaporative cooling, reusing server heat, and a projected PUE of 1.5, the plans drew fire from environmental group Greenpeace.

The group criticized Facebook for siting the facility in a region where much of its energy would be drawn from dirty coal plants. Although the dust-up died out without any change of plans from Facebook (and in the wake of the revelation that Greenpeace's own data centers aren't as green as they could be), Greenpeace took the expansion announcement as an opportunity to once again rake Facebook over the coals.

"While it's rumored that Facebook has adopted a new energy policy in response [pressure from users and environemental groups], today's announcement shows that this policy does not have any teeth," Greenpeace climate policy analyst Gary Cook said in his statement. "Given that Facebook, along with cloud-based computing as a whole, is projected to quadruple in size over the next ten years, it's critical, both for the environment and the financial viability of the industry, that Facebook and other major cloud based companies such as Google and Microsoft build a green cloud, not a brown one that increases demand for coal."

Greenpeace has been working on the greening of cloud computing throughout this year; back in March it released a report delving into the environmental impacts and inherent inefficiencies in most cloud-centric data centers.