[LINK] Greening ICT

[Carl Makin]

On 11/02/2009, at 9:24 AM, Stilgherrian wrote:

> On 11/02/2009, at 9:15 AM, Richard Chirgwin wrote:
>> I'm not so sure it's "very little". Each rack needs front and
>> (preferably) rear access, and that access has to be usable. So for a
>>
> Or, each rack can be mounted on a track so that you slide open the
> 1.5m gap between the rack you want to work on and its friend like,
> showing my age, a Compactus.



Front and rear access is important but actually cooling capacity  
becomes the limiting factor in most data centres.  Most old style data  
centres with airconditioning units against the walls having cold air  
delivered via an underfloor plenum and hot air extracted from the roof  
space typically max out around 5KW average per rack.

One local commercial data centre (Canberra) uses the APC hot aisle  
containment system (www.apc.com) where the cooling units are actually  
between the racks sucking the hot air from an enclosed space at the  
rear. This place supports 7.5KW average per rack however they can be  
upgraded to 12KW average per rack (at a suitably upgraded price of  
course).

Closer to Stil's idea is the "Data Centre in a 20ft Shipping  
Container" such as Sun's Project Blackbox (http://www.sun.com/products/sunmd/s20/index.jsp 
) which fits 8 racks at either 12KW or 25KW average per rack.  The  
racks run down both sides facing sideways with a cooling unit between  
each rack sucking the hot air from the rack in front and blowing cold  
air into the rack behind.  The racks slide into the centre aisle for  
servicing.  These seem like a great idea until you realise you need  
another container full of support gear such as a UPS and water  
chillers (and the cooling tower on the roof) to support it.

Where I work we've just been looking at all of this in the context of  
implementing a disaster recovery facility.


Carl.