IBM is going build a supercomputer more powerful than ever built before for the Energy Department's National Nuclear Security Administration.

Worthy of its name, Sequoia will be based on future IBM BlueGene technology and exceed 20 petaflops.

IBM says Sequoia will include 1.6 million IBM POWER processors housed in 96 refrigerator-sized racks occupying 3,422 square feet and brags that it will be more powerful than the combined performance of all of the systems on today's list of TOP500 supercomputers while offering "unprecedented" levels of energy efficiency.

Although the behemoth is meant to ensure the safety and reliability of the country's aging nuclear deterrent, it's actually supposed to have broad application like a 40x jump in weather forecasting, making it possible to predict a tornado's path, and a 50x refinement in predicting earthquakes and their effects on a building-by-building basis across an area as large as Los Angeles County.

It's also simply supposed to help maintain US leadership in high performance computing.

Sequoia is supposed to be deployed in 2012.

Dawn, an initial delivery system based on BlueGene/P technology with speeds over 500 teraflops or 500 trillion calculations per second, will go in this quarter, laying the applications foundation for Sequoia, which is calculated to be 10 times faster than the most powerful system today.