At 3:17 PM +0000 3/29/08, Paul Vixie wrote: >page 10 and 11 of <http://www.panduit.com/products/brochures/105309.pdf> says >there's a way to move 20kW of heat away from a rack if your normal CRAC is >moving 10kW (it depends on that basic air flow), permitting six blade servers >in a rack. panduit licensed this tech from IBM a couple of years ago. i am >intrigued by the possible drop in total energy cost per delivered kW, though >in practice most datacenters can't get enough utility and backup power to run >at this density.
While the chilled water door will provide higher equipment density per rack, it relies on water piping back to a "Cooling Distribution Unit" (CDU) which is in the corner sitting by your CRAC/CRAH units. Whether this is actually more efficient depends quite a bit on the (omitted) specifications for that unit... I know that it would have to be quite a bit before many folks would: 1) introduce another cooling system (with all the necessary redundancy), and 2) put pressurized water in the immediate vicinity of any computer equipment. /John
