Comments on: Underfloor vs in-row cooling in data centres

By: Brad McIntyre

Brad McIntyre — Tue, 15 Jun 2010 02:03:43 +0000

Everyones comments are correct based on AIR but all Data Centre’s are developed by business drivers and climate. May I suggestion to explore all options by speaking to the vendors like APC, Emerson, Blue Box, Uniflare etc and asked them to tender on data centre engineering and design capabilities based on your requirements as they have your best interest with your environment.

By: erwin born

erwin born — Sun, 30 Aug 2009 20:29:37 +0000

Hi,
Ever considerated free outside air cooling ? that is a really efficiënt way of cooling. Trends are going in this direction, and server manufactorers are currently redesigning to meet the required ETSI qualifications. Telco operators have been doing this for years…. and yes 8kw a rack is more than low density, but certainly not a constraint to kick out underfloor cooling by fact. we’ve designed many datacenters with underfloor cooling going to 10-12kw a rack, in a very efficiënt model (both investment as the energy bill). grtz. Erwin Born.

By: Vince Pratt

Vince Pratt — Wed, 15 Jul 2009 20:38:23 +0000

Hi Jose,
I’m interested why datacenter design consultants have warned against APC’s InRow/hot aisle containment noting high risks -

There are many options of course and with your particular set of circumstances noted I personally see the APC solution a viable option.

Data Centre designs need to consider high density for the mid-longer term future unless is it built for a short term period.

You can attempt to reduce power densities with even throttling back using more energy efficient ICT hardware technologies.

However vendors are still going moving towards squeezing more into a rack (general blade technology- i.e. HP adaptive infrastructure, CISCO unified computing) and 10 – 20kW will start becoming standard in 5+ years time -

Data Centre design should be factored for longevity and if you are hitting 8kW/rack now then opt for a scalable high density solution now (underfloor is definitely not an option).

Just my humble option – keen to hear from others (btw great blog Tom and excellent comments from all…) Cheers!
Vince

By: Jose San Martin

Jose San Martin — Wed, 30 Jul 2008 16:04:22 +0000

We are in the starting phases of a 400-600kW datacenter in Madrid where energy efficiency is our main concern. We have severe space limitations in the clean room (3,5m/10,5ft high, 200m2/1800ft2), but not in the floor below. That means HUGE mean power density (8-10kW/rack), therefore APC InRow is right now our winning horse.

However specialized datacenter design firms consulted warn against this technology, and previous installations in Spain are scarse.

Are really risks so high? Should we go for a traditional solution and reduce power density? What is your opinion?

TIA

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By: climate Storage

climate Storage — Wed, 04 Jul 2007 14:15:17 +0000

We’re in the cold winter and quite few hot days in West Galille, Israel. Brandstetter Systems Ltd installed in 1994 saves us approx a third of consumption bill. The small company is the brainchild of Dr A.Brandstetter who worked in Australia many years + his two sons.

By: Tom Raftery

Tom Raftery — Mon, 25 Jun 2007 09:33:28 +0000

ask yourself would you rather contain the cold aisle with the room flooded with hot air, or contain the hot aisle with the room flooded with cool air. If you consider the volume of air at the desired temperature it becomes obvious that containment of the hot aisle is more favorable

John, thanks for your comment. I have to take issue, though with what you are saying above. We have a large room with a high ceiling. The mean ambient temperature in Cork is 10C – the temperature of the air exiting the back of the servers is 30C-40C.

Dumping the hot air to the room allows for cooling by the ambient air free. This is extremely energy efficient.

The only negative to this approach is that people entering the data room will be surprised the first time they enter to find it is warm. This is an issue of perception which we will address with all customers and potential customers before allowing them onto the floor.

By: John Bean

John Bean — Thu, 31 May 2007 18:46:07 +0000

InRowTM Cooling Architecture is not being recognized for its efficiency gains over raised floor perimeter cooling. At the end of the day the connected fan power for InRow cooling is substantially less than conventional raise floor computer room air-handlers. Please consider that InRow cooling may only require 0.34 watts (or less) per CFM versus 0.6 watts per CFM for typically perimeter air-conditioning. The major drivers for the additional fan power are: system effect on fan discharging into floor plenum, static losses of fan, and significantly higher internal cabinet losses for perimeter air-conditioning. Beyond this perimeter air-conditioning will circulate more CFM per kW of IT load than InRow solutions, assuming containment is not used.

Regarding the containment of the cold aisle, ask yourself would you rather contain the cold aisle with the room flooded with hot air, or contain the hot aisle with the room flooded with cool air. If you consider the volume of air at the desired temperature it becomes obvious that containment of the hot aisle is more favorable.

Furthermore InRow architectures are not susceptible to all of those under floor obstruction and problems associated with achieving desired airflow balance of perforated tiles.

By: Adam Beecher

Adam Beecher — Sun, 20 May 2007 12:51:51 +0000

We’re already using something similar to those grommets Fintan, albeit round rather than square. We use those for data, and another type of sealable grommet for power, 2x.

We’ve discussed using barriers to direct airflow under the floor, but I think it’s something we’ve decided to come back to. There will of course be an element of fine-tuning.

Thanks for your comments.

adam

By: Fintan Costello

Fintan Costello — Sat, 19 May 2007 17:10:43 +0000

Cold aisle containment is definitely a very efficient system and its great to see a Data Centre using it in Ireland.

Other things to factor in would be to to reduce by-pass air loss through cable openings by using Koldloks http://www.datacleaneurope.co.uk/blog/?cat=24

We are also seeing a lot of companies starting to use the pleanform under floor air barrier system to direct the cold air to exactly where it is needed. http://www.Plenaform.com