In today’s data-driven world and with the ever-increasing trend towards “cloud based” information, Aspen Pumps Group Technical Director Chris Gee takes a look at the role which cooling has to play and the importance of continuous innovation.
Data centres are vital to global connectivity. Our content – from laugh-out-loud YouTube cat videos to financial and sensitive personal information, is all stored and distributed from these data centres 24/7.
By 2020, at least 1/3 of all data will be cloud-based, so it’s imperative that business critical I.T. equipment is kept and maintained in optimal conditions. Even for small businesses, short outages can cause significant disruption and any downtime can result in reduced productivity and loss of revenue.
Small but mighty
The rooms which contain and process this valuable data vary in size from small, single rooms serving small organisations (known as a server room) and scale right the way up to those of internet giants such as Google and Facebook. The energy consumption for a typical data centre can vary from just a few kW into MW depending on the size, with approximately 35% of consumption used on cooling and HVAC. Even in smaller server rooms, systems run 24/7 and can consume vast amounts of electricity, generating heat which needs to be removed to minimise the risk of fire from components overheating and to optimise performance - cooling is therefore a vital consideration. This cooling produces condensate which needs to be removed and gravity drainage systems are commonplace due to the obvious need for water to be kept well away from IT equipment.
Manufacturers such as Aspen Pumps Group are constantly innovating to create alternatives. We have worked hard to build core competences in smart controls and pump technology. The Hi-Flow Max Tank Pump has a much better and patented centrifugal pump than any other on the market. Though it is designed primarily for ceiling voids, since server rooms are not usually customer facing, there is no reason why this reliable pump could not be situated alongside a mini split system in a server room and used to pump the condensate far away from valuable IT equipment.
The bigger picture
One of the most common methods of cooling in large and medium server rooms are known as CRAC units (computer room air conditioners). The server rooms are placed onto a raised floor and the CRAC units then distribute conditioned air to the server racks. The units have heat exchangers inside which are connected to refrigeration units to remove heat from the rack. Some can also humidify or dehumidify the air which is very important to control the static electricity in the air. The conditioned air is moved by a fan in the CRAC unit into a void under the floor and leaves the floor through strategically positioned holes in the floor. This air collects the heat from the units, rises up and is sucked back into the units to be reconditioned. After much trial and error over the years, hot and cold aisles are commonly used today, meaning server units are placed back to back, creating a convection effect to keep the hot air from recirculating where it is not wanted. An improvement on this has been hot air containment aisles which stop the flow of hot air from mixing with the valuable cold air using a physical barrier like a ceiling void.
Data giants such as Google are a huge operation. Google’s data centre in Oklahoma is estimated to measure in at 980,000 square feet, so it’s no surprise that these companies need large-scale methods of cooling far beyond the needs of most businesses. While Google does use the hot aisle method for cooling, the entire room serves as the cold aisle. Raised floors are used but no perforated flooring. Instead, all the cooling magic happens in enclosed hot aisles, using cooling coils with chilled water which serve as the "ceiling" for these hot aisles. The aisles also house large stainless-steel pipes that carry water to and from cooling towers housed in the building's equipment yard. With environmental impact an increasing factor for all businesses, Facebook claims its data centre in Sweden is “one of the most efficient and sustainable data centres in the world” using the biting -41°C air to cool the thousands of servers within the building, with any excess heat harnessed to heat offices.
The reality for most businesses is a server room, as opposed to a larger data centre but cooling is just as critical. A mini split system may be used to cool the room and with this method comes the opportunity to use pumps to direct the condensate away. Pumps such as Aspen’s Peristaltic are designed to be placed as far as 3 metres from the AC unit with no impact on performance. This means they can be sited remotely, if needed, to allow for easy maintenance access and no worries about water near equipment. The other great thing about these pumps is that they are built to last – many running for 30+ years!
Cooling data centres can be a huge task but one which is increasingly essential to support the worldwide exchange of information on which we have come to rely. With manufacturers such as Aspen Pumps Group leading the way in HVAC innovation, the future looks bright for technology which can deal with the ever-growing need to keep our information safe.