Redesign Your Data Center Energy Use-Put A Cork in It

I have mentioned Tom Raftery before but after visiting him and his colleagues as one of the guest speakers for the it@cork Green IT event yesterday I thought a follow up was definitely in order. Tom was responsible for redesigning the cork internet exchange to make it more efficient and took some intriguing design decisions, at least one worthy of Buckminster Fuller. It was Fuller for example who realised that we don’t need to have our showers so hot if the ambient temperature of the bathroom is a little bit warmer. Sounds obvious but then so often the really smart game-changing things do. Every time you see one of those timer/light/warmers in the ceiling of a US hotel room you are likely seeing Fuller’s thinking at work. Fuller was an iconoclast. It seems to me that in his own way so is Tom. And today more than ever we need iconoclasts at work, rethinking business as usual.

What is more, Tom is gas, as they say in Ireland (well on TV shows about Ireland, anyway. Probably about as real as the Irish tat in the airport) . It was brilliant to see the blank looks on the audience’s face as he said one of his slides was “geek porn”. About half an hour later I made the same mistake, telling the audience “unfortunately unlike Tom I have no porn in my presentation.” Cue more blank faces. Perhaps it was a bit early…

So what is so interesting about the cork internet exchange? Last time I mentioned the case study a couple of things went over my head. The most notable of which comes in slide 19 of this presentation.

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What was the design decision that makes all the difference at Cork? Well you see a normal data center has hot aisles (backs of servers) and cold aisles (fronts of servers), but the data center has an average ambient temperature based on convection and flows of these air streams. Indeed most data centers are pretty much designed and run with the ambient temperature in mind. So what did Tom and team do? They put a cork in it. They sealed the cold aisles, which means that when you walk into the data center you’re hit with a blast of 30 degree celsius air.  For humans the temperature is very high, but where it has to be cold, it is. Which is pretty smart if you ask me. Of course this idea would never fly in America where humans can only stand a very small ambient temperate range between 65 and 70 degrees F. But in Europe I can certainly see some organisations trying something similar. To be clear- the data center heat is also used to warm the offices and hot water at cix. Says Tom: “Our central heating is powered by Intel”. The crack about Americans and air-conditioning above is a little unfair- after all- Cork has the native advantage of not being as hot as California, or locations where many US data centers are located. But still- it surely makes sense to concentrate on cooling machines rather than people when you’re designing a data center.

Tom also talked some madness about electricity companies paying us to use electricity when the wind farms were working at peak load, but that’s a subject for another time.

One final thing I want to point out is that Tom is currently looking for a gig. He is world class as a social media guy, and he is also hardcore on the green data center side. If you’re looking for help look him up. He is moving to Seville soon, but location doesn’t matter with this interweb thingy.

Here are his details:

tom at
Tel +353-21-490 8485
Mob +353-86-3840828


  1. Green IT Ingenuity at Cork Internet Exchange…

    Let me preface this post with the obvious, I am not an engineer. But, it would be fair to say I’m green. So, consider what follows information sharing, but definitely not analysis. Other than, “Hey, what Cork Internet Exchange did…