Hot aisle containment vs cold aisle containment
I came to Interop this week to check out some of the latest technologies in the Data Center space. It was interesting to see APC’s Hot Aisle Containment kit (see below).
I was particularly interested in it because in CIX we have decided to go with containing the cold aisle instead of the hot aisle.
I spoke to one of the APC guys and asked why they decided to contain the hot aisle. He said it is more efficient for their equipment because they have the have the air handling units in-rack. Air handling units work more efficiently the warmer the air they get so it makes sense for APC to contain the warm air, direct it to the air handling units and benefit from the efficiencies.
In our case our air handling units are in room as opposed to being in rack so it makes sense for us to contain the cold aisle and vent the hot air to the room so we can benefit from the efficiencies of our air handling units taking in warmer air and we also get free cooling from Cork’s ambient temperature of 10C!
August 2nd, 2008 at 11:01 pm
Over time Hotaisle Containment will pay for itself compared to cold aisle containment.
You don’t need nearly as much capital cooling equipment because the heat is so well contained/converted back to cool air.
August 30th, 2008 at 5:47 pm
Cold Aisle Containment is even more efficient!
November 25th, 2008 at 3:39 pm
The effeceincy comes in two parts
firstly the seperation of hot vs cold air
secondly the close coupled cooling
The second make a huge saving in fans speeds sizing etc, very similar to chilled beams in a normal building HVAC strategy.
This is where containing the hot aisle works better than the cold. Keeping the cooling units as close to the load as possible can have of a 10x saving in fans sizing / speed / power requirements. Having the hot air from the back of the server directly into the cooling coil can double the capacity of any coil.
June 21st, 2009 at 8:19 pm
Hot aisle/cold asile,hot asle containment or cold asile containment will all produce savings in power comsumption and provide optimum cool air supply to the product of your focus. Each of the above have their merits.But the product saftey in the event of outage and the recovery time for the room must be assesed before implementing any of the options mentioned.
With respect to data centers the product or server is fed from ups power which is more costly than NC power, but provides power during outage. So if cold asile containment is your choice it is imperitive that all CRAC units(computer room air cooling) be supplied by ups because the temp rise in the room will be in seconds instead of minutes and so reduce your recation time and so place the room in a position of risk. the volume of cold air in a cold asile containment enviorment is ristricted to the area of the cold asile and the rest of the room is hot this is why you must assess the effect an outage will have on equipment and consider ups supply to CRAC units. This extra cost makes this less efficent than first seems.
The hot asile option has the hot air contained and the room temp cold at optimum running temp for the product and so in the event of outage the recation time is much increased and places the product in a safe position. This option does not erquire ups supply,making this the most cost effective and risk free option.