Slideshow: Government's 10 Most Powerful Supercomputers (click for larger image and for full slideshow)

The National Security Agency is designing a new $895.6 million supercomputing center that will be constructed at its Fort Meade, Md., headquarters over the next several years, Department of Defense budget documents reveal.

The NSA's new High Performance Computing Center, slated to be complete by December 2015, will be designed to with energy efficiency, security, and lots of "state-of-the-art" computing horsepower in mind, according to unclassified specs found in the documents, which detail numerous military construction project budgets, including several NSA efforts.

NSA has long been a supercomputing powerhouse. The secretive signals intelligence agency purchased the first Cray supercomputer in 1976, and even keeps two Cray supercomputers on display at its National Cryptologic Museum alongside spy gadgets such as centuries-old code books and a working German Enigma machine from World War II.

The specs for the new supercomputing center read much like the NSA is building a massive data center, with typical requirements for raised flooring, chilled water systems, fire suppression, and alarms. Power requirements are 60 megawatts, equivalent to the power requirements of Microsoft's recently completed 700,000 square foot data center in Chicago, which itself is one of the largest ever constructed.

Despite the power requirements, the facility will be built as efficiently as possible, with the goal of attaining a LEED Silver certification by conserving water, energy, and materials.

The High Performance Computing Center also will include tens of millions of dollars in security features, such as an estimated $15.1 million in building security and $21.7 million on perimeter control. The security features will include a vehicle cargo inspection facility, a visitor control center, card access control, video surveillance, intrusion detection systems, chemical, biological, radiological, and nuclear detection systems, and perimeter fencing, among others.

NSA is requesting $84.7 million for its new High Performance Computing Center in fiscal 2012, including $35 million for planning and design. That will be followed up with a planned $399.9 million in fiscal 2013, and $431 million to complete the center in fiscal 2014.

In addition to the supercomputing center and a few non-tech related construction projects, the budget documents also indicate a $246.4 million 2012 request for NSA's new cybersecurity data center under construction at Camp Williams, Utah and a $68.6 million request for a new generator at NSA's communications intercept site at RAF Menwith Hill in England.

While NSA's total budget remains classified, a few other details on its tech spending can be gleaned from other documents, including a $944 million information assurance request for fiscal 2012, which is 5.5% more than this year's request. Accounting for the difference, according to the request, is a boost in operational spending for "advanced network operations and intrusion analysis."

The cybersecurity request details a number of NSA's planned efforts for 2012, including continuing development of more advanced cryptography for nuclear command and control systems and building partnerships with the IT and communications sectors on mobile applications and cloud security.