No stranger to ranking high on the Top500 list of supercomputers, IBM is also racking up eco-points with a formidable presence on the Green500 list.

In the latest ranking, IBM dominates the top 20, with the first spot going to a BladeCenter QS22 Cluster housed at the Interdisciplinary Centre for Mathematical and Computational Modeling at University of Warsaw. Powered by Cell processors, the system produces 536.24 megaflops per watt and has a total power envelope of 34.63 kilowatts. On the Top500 list, the supercomputer takes the 422nd spot.

Rounding out the top three are the DoE’s BladeCenter QS22/LS21 Cluster and IBM’s Poughkeepsie Benchmarking Center, both at 458.33 megaflops per watt.

The Green500 crew also offers some interesting observations. Predictably, efficiency is improving. Although the survey finds that the Green500 are consuming more power in aggregrate, they are 10 percent more efficient on average. And there’s also this note on commodity processors:

Four- and six-core commodity processors keep improving in energy efficiency (265 Mflops/Watt to 273 MFlops/Watt) and surpass previous-generation custom processors. Now, 20 of the top 50 energy-efficient supercomputers utilize commodity processors.

You can find the latest Green500 list here.