Cold aisle containment

Effective cooling is essential for data centres: this is an indisputable fact. Without constant temperatures, data centre equipment cannot perform efficiently, and is at risk of breaking down. An unreliable service leads to customers being repeatedly hit with downtime and disruption.
While most data centres are now lowering their PUE through the use of efficient equipment and improved cooling methods – free air cooling and cold aisle containment are much more energy-efficient than other commonly-used methods.

Cold aisle containment is a layout designed to solve these problems whilst at the same time achieving energy efficiency and reducing cooling costs, all through successful management of airflow.

How does cold aisle containment work?
Data centres that employ cold aisle containment are laid-out to achieve efficient cooling through successful management of air flow. The placement of servers is carefully and meticulously planned to allow for maximum efficiency, and to keep the temperature levels constant. Cold air is then trapped exactly where it is needed, directly in front of the servers’ air intake. As it flows through the servers, hot air is expelled to the back of the cabinets ensuring there is no chance of the hot exhaust air mixing with the cold inlet air, keeping the temperature consistent.

Imagine your refrigerator at home, cold aisle containment works in the same way. Leave the fridge door open and the room and fridge contents will get hotter, because for every degree of cooling undertaken takes two degrees of heat creation through the mechanical losses. Close the door and the contents will cool, with the room only warming slightly. Cold aisle containment is like closing the refrigerator door, a phenomenon clearly visible in supermarkets where open food cabinets are being replaced with closed cabinets.

What are the benefits for organisations?
A result of the consistent cold air flow means that hot air spots are avoided, improving the efficiency of the cooling system and saving energy costs. As cold aisle containment can be implemented within most data centres it is an accessible way for companies to save money, improve their effectiveness and become more environmentally friendly. Aisle containment can be controlled using adjustable floor vents, allowing air to be focused according to demand on the areas that need it, rather than being pumped blindly into the wrong place.

What factors should be considered when outsourcing?
Businesses which take PUE into consideration when sourcing a data centre, need to consider how it is calculated and over what period of time. Remember it is relatively easy for a data centre to manipulate its PUE and often exclude the energy used for office functions. Ensure you are made aware of its energy procurement policy and its corporate responsibility on energy saving extends to its green purchase policy.

What does the future hold for cold aisle containment?
Cooling will always be a key concern for data centres, however balancing this need with achieving a low PUE is no longer something data centres can ignore. It is achievable, however, and increasingly customers will be demanding that centres invest in innovations to keep their service at a high standard, while maintaining cost control.

As a Data Centre Manager operating both a traditional data centre facility and a modernised new build, I know that the average PUE of a traditional data centre in the UK is 2.0 and needs to be a lot lower. That is why we’ve worked hard to tackle this and have managed to attain a PUE of 1.8 at our traditional facility and 1.25 at our new site in Reading – something we’re extremely proud of.