To me this seems like overkill for what can be nearly accomplished with 240V 3-phase power. Most enterprise class systems have the option to be delivered with 240V 3-phase which is about as close to DC as you can get on the AC side but doesn't require the conversion and consequently the heat generated by the conversion that requires additional cooling.
If there is a desire to be more green in a computer room then it should start with the actual computers themselves. Most computers run constant speed fans that are consuming a large amounts of electricity when it is not needed. If a CPU and other components of a system are not being used then they do not need to be cooled as much. If a disk drive is not being accessed as much then it doesn't need to be cooled. Integration of the cooling with the monitoring of the systems usage to reduce the cost of cooling systems is the direction that should be taken.
Then there is the whole idea of having large numbers of servers sitting in a computer room with each server consuming electricity while they are being utilized at an average of 20%. I still don't understand how a company can look at a computer room full of pizza box servers running at 20% utilization and feel that they are getting their monies worth. Consolidation of servers into either blade enclosures that are running some kind of a virtualization software platform or larger servers that allow multiple layers of consolidation is the biggest bang for the Green dollar there is. There are companies who have cut their computer room costs by millions of dollars per year by consolidating hundreds of servers down to tens of servers.
The cost involved with AC to DC conversion of computer rooms would be unrealistic in most facilities where tremendous cost savings can be obtained by simply changing to newer technology.
Phil
-----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of David Nicol Sent: Tuesday, December 18, 2007 8:23 PM To: kclug Subject: didn't someone tell me that telco equipment had 40vdc racks once?
I've been suggesting this kind of thing for years
http://www.news.com/8301-11128_3-9835281-54.html?part=dtx&tag=nl.e433
-- Looking back, I realize that my path to software as a career began at the age of seven, when someone taught me to count in binary on my fingers. _______________________________________________ Kclug mailing list [email protected] http://kclug.org/mailman/listinfo/kclug