Power delivery and cooling are two of the biggest challenges facing data centres today. Steve Warnock, managing director of the Coolmation Group, explains how IT managers should consider  compressor chillers when reviewing climate control, since the technology offers significantly higher efficiency

Although the vast majority of IT people are not experts in cooling technology, they may be aware of Turbocor compressor chillers. When Turbocor compressor chillers were launched a few years' ago they received rapturous applause, offering data centres a highly efficient chiller that could significantly cut carbon emissions, fuel usage and costs in one fell swoop. Their introduction was timely with data centres having to weigh up their air conditioning choices with increasing pressure from escalating server numbers, rising energy prices, as well as EU regulations, including the F-Gas Regulation, and a raft of building legislation introduced by the Government to reduce the UK's carbon output.

However, the Turbocor compressor was a huge technological leap, so it was not surprising that the technology took time to overcome teething problems. The Turbocor compressor brought huge energy savings but its innovative design was so dramatically different from previous compressors that it took time to produce the optimum relationship between chiller and compressor. Although this refining process has now resulted in proven Turbocor chiller technology offering all the energy savings the prototype compressor promised, therefore providing data centre managers a reliable and highly efficient air conditioning solution for critical cooling of computers and servers.

So why should data centres opt for Turbocor technology? For the data centre industry having a Turbocor compressor at the heart of a chiller means a company can depend on the technology's simple design, which incorporates just one moving part, to increase the reliability of the equipment and help avoid unscheduled system outages. This is key within the data centre industry, in order to maintain the integrity of data and avoid costly downtime.
Meanwhile, with the compressor generally the single, largest energy consumer within the air conditioning system and at the heart of chiller operation, it is not surprising that Turbocor chillers are also such an important step forward for power saving. In fact, in its target capacity range, there is no other compressor currently on the market that produces better efficiency in operation.

So how do Turbocor chillers achieve such high operating efficiencies? Let me explain. The Turbocor, oil-free compressor incorporates an inverter-driven, permanent magnet motor and magnetic bearings. Typically, traditional induction motors of this size are in the 92% efficiency range, but the Turbocor compressor’s permanent magnet DC motor provides an efficiency of between 96 to 97%.

The Turbocor’s magnetic bearings further enhance efficiency by avoiding the friction typically associated with traditional oiled bearings. In fact, magnetic bearings have over 500 times less frictional losses than conventional bearings. The frictionless bearings reduce the starting current to just 2A removing the transient starting spikes frequently associated with screw compressors and the need for expensive soft start arrangements, as well as eliminating the risk of penalty charges for exceeding maximum power demands. A reassuring fact for the data centre sector.

However, it is the seamless integration of the Turbocor compressor within the chiller as a whole, which is now providing new outstanding and reliable operating efficiencies. For instance, Coolmation, has launched Rhoss’ new series of Eurovent-certified Turbocor R134A cooled chillers which are available from 150kW to 2,100kW and have been developed through a unique partnership between Rhoss and the University of Udine. The result is that Coolmation’s Turbo Power chillers include innovative design features, which complement the Turbocor compressor to offer even higher efficiencies.
Turbocor chillers, such as Coolmation’s range, now offer significantly higher operating efficiencies than chillers using scroll, screw or reciprocating compressors. Compared with screw compressors, Coolmation’s Turbo Power range has an EER of up to 4.0 at full load conditions and in excess of 8.0 at part load, representing an efficiency increase of 10% and more than 100% respectively.

Another benefit of the new generation of Turbo Power chillers is a flooded type evaporator which optimises the compressor and is more efficient than a shell and tube direct expansion evaporator. It is this symbiotic relationship between the compressor and chiller that offers the data centre industry increased benefits.

Low maintenance is another key feature of this type of chiller which is partly due to the simplicity of the compressor - it comprises only one moving component - the compressor shaft. Magnetic bearings keep this high-speed shaft suspended in the air and frictionless, so reducing wear, extending the chiller’s lifetime and keeping maintenance to an absolute minimum. The compressors are also oil-free which improves efficiency and helps to keep maintenance costs down by avoiding the need for oil management systems. Offering great reliability Turbocor compressors are manufactured from aircraft grade aluminium castings with high strength thermoplastic electronics enclosures. The high standard of workmanship also means a reduction in potential refrigerant leaks, making it is easier for data centres to comply with the F-Gas Regulation.

We recognise that the vast majority of IT people are not experts in cooling technology, yet they should be aware that proven systems do exist which are capable of delivering the effective cooling that servers require. Talking at an early stage to a specialist in cooling systems, such as Coolmation, can save time and hassle and supply a very cost-effective cooling system providing the right environment for servers to do their jobs effectively, without the risk of overheating, repeated crashing and data loss. Following the design advances that Turbocor chillers have now undergone, the proven compressor technology is now set to take centre stage and offer a truly efficient and low carbon solution.