The current Prineville data centers are 334,000 square feet, while the new one will be 62,000 square feet. The new one also won’t add any jobs to the region.

Adding on smaller facilities at these huge data center locations isn’t unusual. Apple is adding on a small (21,000 square foot) “tactical” data center at its North Carolina site, next to its 500,000 square foot iCloud data center.

But Facebook’s infrastructure will be important to watch. The company is in a growth phase and its number of servers have soared to an estimated 180,000, up from an estimated 30,000 in the winter of 2009, and an estimated 60,000 by the Summer of 2010. That’s one of the reasons why Facebook is now keeping close track of its energy, water and resource consumption of its data centers.

For more info on data centers check out:

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In an interview last month, Weihl told me that one of the reasons he joined Facebook from Google — where he was the search engine company’s Green Energy Czar — was because of the massive opportunity to help deliver sustainability through Facebook’s social platform. Over the next six to 12 months, we’ll increasingly connect with third party app developers that can help us deliver this goal, and “the potential there is just enormous.” said Weihl.

The first of these types of third party partnerships is a deal announced late last year with energy software company Opower. Opower created a Facebook application that enables users to check out their energy usage compared to friends and national averages, get energy efficiency tips and, down the road, play games that make energy savings competitive. The app was launched in April in beta with 16 utilities (representing 20 million h0useholds).

While there is plenty of this type of energy efficiency software out there, building an energy app on top of Facebook’s social platform has unique opportunities to change people’s behavior. Because the app can compare their energy usage to their actual friends, it “is much more personal and seems likely to help people pay attention more and make a change,” explained Weihl.

The open social graph could be a fundamental key to cracking the code for behavior change — everything from turning off lights, to lowering air conditioning to buying LEDs, to participating in utilities’ energy efficiency programs. People are influenced by a variety of things, explained Weihl, but most people can be covered under some combination of: saving money, competing with peers, and doing good. Beyond energy efficiency apps, Weihl says Facebook has been looking to work with developers building apps around things like recycling and electric cars.

In 2010, Facebook says it “woke up” to using its platform for sustainability, and increased those efforts in 2011. The company has been working with environmental groups like the Environmental Defense Fund, and came to an agreement with Greenpeace last year to move up clean power on its list of criteria for siting where it builds data centers. Facebook also has an industry-leading project to open source the energy efficiency hardware for its data centers. However, the work with third parties around delivering sustainability apps for social good has been relatively modest at this point.

Weihl will also help Facebook monitor and manage its overall company energy usage and carbon emissions. Weihl also intends to help Facebook work with utilities to find more options for clean power for data centers.

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