Cookie policy: This site uses cookies (small files stored on your computer) to simplify and improve your experience of this website. Cookies are small text files stored on the device you are using to access this website. For more information on how we use and manage cookies please take a look at our privacy and cookie policies. Some parts of the site may not work properly if you choose not to accept cookies.


Rackspace shares design of new free-cooled London site

Built by Digital Realty, Rackspace Crawley is first large UK site with no chillers - and Open Compute has the design 

Managed cloud provider Rackspace has opened its new 6MW data center in Crawley, south of London, built by Digital Realty and using only outside air for cooling. The design has been shared with the Open Compute Project .

The data center is the first at this scale to be built in the UK without any mechanical chillers, says Rackspace, and is designed to have a PUE (power usage effectiveness) of 1.15. Two of its four data halls are open - and Rackspace showed visitors round on April 22 before beginning to install equipment for customers. 

Rackspace Crawley

Power and cooling plant  is on the roof to save space

Source: Rackspace

The air is fresh and sweet (up on the roof)

To save space, and build an efficient vertical flow of power and air, Rackspace and Digital Realty have put all the power and cooling systems on the roof. The physical layout and design idea will be shared with the Open Compute Project, making it freely available to other data center builders, Rackspace announced at the launch. 

The cooling units on the roof are from Excool, using indirect outside air or “free” cooling, taking in air to circulate through a closed loop system based on contained hot aisles. When the air temperature is warm, the Excool units add in evaporative cooling, with a water spray system.

This allows the site to operate without mechanical chillers, reducing its energy usage. Water for the evaporative cooling system will be harvested from the building’s roof to further reduce environmental impact. 

The power distribution system uses Emerson units, and a conventional battery-backed UPS with conversion to direct current on the roof and back to AC for distribution to the racks. High voltage DC distribution was considered but it still requires a lot of conversions, Digital Realty staff explained to DatacenterDynamics.

The building has a BREEAM “excellent” rating, and supports the latest (2011) ASHRAE guidelines. It is based on contained hot aisles which rest on a solid concrete floor. The air inside the building is at 24C and the hot aisles are at 36C.

Rackspace Crawley

Rackspace Crawley

Source: Rackspace

Power is distributed from above using A and B power feeds, color coded in green and yellow

Open Compute 

The design is based on the Open Compute Project’s principles, with less weight, waste and power requirements, although the site can accommodate both Open Compute racks and conventional systems. At capacity it can hold 50,000 physical servers, and its current 6MW capacity can be extended to 12MW.

The site extends an ongoing Digital Realty and Rackspace partnership onto a third continent, said William Stein, Digital Realty’s CEO: ”We are delighted to see Rackspace establish its new managed cloud data centre with such outstanding eco-credentials. With competition growing for facility services across the UK and Europe, we are pleased Rackspace choose Digital Realty as a provider to collaborate on this bespoke facility in Crawley.”

The ribbon was cut by local Conservative MP Henry Smith, who has visited the project during its genesis, and is currently standing in the UK’s General Election. ”I fully understand PUE,” quipped Smith,” and if I am not re-elected in May, I will be sending my CV to Rackspace.” 

Readers' comments (1)

  • I read with great interest and some incredulity in your news publication this week that Rackspace have claimed to be building “the first large site in the UK with no chillers”. The reason for my surprise is that this is simply not true. Our state-of-the-art 40,000 ft² fresh-air cooled facility Aegis One was opened by the Secretary for Health, Jeremy Hunt MP just over a year ago.

    Whilst their claim may not be true, it is heart-warming to know that companies like Rackspace are following Aegis Data’s market lead. Our customers are already benefitting from the efficiencies and cost effectiveness of our direct fresh air cooling. If any of the Data Centre Dynamics team are interested in a greater insight on the benefits of and how best to manage a fresh-air cooled facility, we should be very happy to show them round our Aegis One data centre in Godalming, Surrey – perhaps you would like to join them on the tour?

    I look forward to reading your next edition

    Unsuitable or offensive? Report this comment

  • Dear Gerald

    Many thanks for your comment. The Rackspace site is certainly the first large data center in the UK we have heard about that is built with no traditional CRAC units. If yours is also in this category, we're very interested to hear about it now.

    It's our understanding that many sites use fresh air where possible, most have some traditional cooling in place for hot days or as a backup to ensure availability.

    I can't find a story on our own site about Aegis One, so it looks as if we weren't at your launch last year.

    Meanwhile, your own site describes your use of free air cooling - and promises a very impressive design PUE of 1.12 - but it does say there is a "DX system for ancillary cooling"

    Elsewhere it says the site has "N+1 Cooling infrastructure delivered under floor with (CRAC) units"

    Clearly there is more to understand here, and we look forward to hearing more. Thanks again for contacting us.

    Peter Judge

Have your say

Please view our terms and conditions before submitting your comment.



More link