The Merlin data centre just opened in Swindon might look like an indoor hockey rink, but it is in fact a bespoke modular data centre created by Capgemini to save some bucks pounds euros on power and cooling as it modernises its computing facilities worldwide. The facility, which is located at an undisclosed brownfield location …
I slide my server in your server-rack last night
I threw me cheeteos at your PFY to keep quiet
Now something's telling me that he's avoiding me,
Come on now BOFH,
You got something i need.
I got a brand new data cent'r and i'll give you the key,
Come get all your rackspace needs from my farming friends 'n' me.
i got 20 servers and you got 43
Now I got a brand new data cent'r and i'll give you the key,
Does the building currently have any servers in it?
It's all well and good having a PUE of 1.08 when it's empty with minimal UPS, cooling, lighting, office gear etc running, but what happens when they stuff it full of kit?
There is a DC in Manchester, with capacity for 147 racks, with a PUE of 1.16, running off similar cooling technology, with actual kit in it.
Empty or full
Well, actually it is more likely to achieve the claimed PUE when it is full as data centre PUE tends to get better with load, meaning a data centre that is only part full is likely to have a much worse PUE than when it is at full load.
The adiabatially assisted economised cooling is certainly not very common but CG are far from being first to use this method to cool buildings in a Swindon like climate, as for complex controls, those make me nervous, give me simple and reliable controls any day over complex and unpredictable failure modes.
What will be interesting is to see what PUE it achieves later on when some customers have demanded 2N UPS and various other efficiency impacting nasties. It is quite easy to get down to 1.1 or so with this type of cooling so long as you don't have much resilience and rely on the cloudyness of the IT platform to provide your failover.
Of course, this assumes they are including all the shared infrastructure in the PUE calculation and not telling porky pies like certain vendors of container data centres who leave out all the important bits like the transformers and UPS when claiming "can achieve a PUE of..."
A trifle sceptical
So 10KW delivered to the IT equipment and only 80W on cooling, lighting, UPS, ventilation, transmission losses, inverters etc.
Forgive me if I'm a trifle sceptical I'd want to know exactly where the measurment points are for this and what lies downstream from them.
However, efficiency it so be applauded. As many runner of large data centres will know, it';s not merely the cost of power that's the problem, it's getting supplied. Power companies often have some limits on the amount they are prepared to deliver to a given location (or at least without paying unimaginably large bills for uplifting distibution networks).
A little less trifle
That would be 800W (80W would be 1.008).
I live in Swindon so will now be out trying to spot the building.
I meant 80W in 1KW of course...
80W on cooling
The major part of the claimed PUE (again, no statement of what it currently achieves or under what optimal conditions it might achieve the claimed value) is that the site does not have mechanical cooling.
From the rather feeble description in the article the cooling is done with some large (read efficient) fans to push external air through the IT area, this is commonly called "fresh air cooling". When it gets too hot for the IT equipment (which with decent air management, sensible maximum values such as 27C intake and the Swindon climate won't be very often) the temperature is brought down using a common HVAC trick of putting the intake air through a water spray (washer) which increases the humidity but lowers the temperature in the process. None of this uses much power.
I am more skeptical about whether losses such as the main HV transformers are included and whether the claimed PUE is for a cloudy container which has no UPS.
Given the style of the building, it would fit quite nicely into the South Marston Industrial Estate or maybe Blagrove over by J16 of the M4.
our survey says...
South Marston, local rag gave that away a while ago: