Intelligent Data Centres Issue 3 - Page 54

Is ambient cooling overtaking compressor technology for data centre temperature control? Tim Bound, Director at Transtherm Cooling Industries, explores the evolving role of ambient cooling technologies in keeping energy costs low in data centre applications. A s demand for data collection, storage and exchange multiplies at an unprecedented rate, experts are concerned that the energy consumption of data centre infrastructure is becoming an increasing drain on the world’s energy resources. In an era where on an annual basis, data centres in the United States alone consume the entire output of 34 of the world’s largest power stations, methods of conserving and reducing the energy input of some of the globes most socially and economically critical buildings is more important than ever. By 2020 the UK will be the largest single market in Europe for data centres and analysts predict this will cost the industry up to £7 billion per year in energy alone. Disclosure of data centre energy and carbon performance metrics is now driving change in a sector where the potential energy savings could comfortably sit in the hundreds-of-millions. There are a number of ways to deliver power savings in data centres, from optimising renewable energy sources, to updating the physical infrastructure of the building, investing in modern server technology with lower heat emissions, or carefully specifying the right cooling equipment. Why is ambient cooling technology increasing in popularity? Historically, data centres have been cooled using compressor or refrigerated technology, often with an adiabatic cooler installed to dissipate the heat generated by the compressor. The performance of this conventional chilling technology has serviced the mission critical data centre sector well thus far, but change is definitely afoot. There is a distinct shift in popularity from traditional compressor based chilling methods to far more energy efficient ambient cooling technologies, with a particular focus on adiabatic solutions due to its retrofitting capabilities compared to other ambient systems such as direct evaporative or heat exchanger technology. Why? The two main drivers for change are a surge in investment in the construction of new or extended data centres, plus a significant improvement in the operating parameters of server technology. Tim Bound, Director at Transtherm Cooling Industries 54 Issue 03 The global data centre construction market is estimated to grow from US$14.59bn in 2014 to US $22.73bn by 2019, at a Compound Annual Growth Rate (CAGR) of 9.3%. This thriving market growth is down to many companies transforming traditional facilities into mega data centres and others planning to build new ‘monster sites’ in the coming years. With modernisation, comes state-of-the- art server technology which is capable of withstanding higher temperatures while maintaining optimised performance and reliability. The modernisation of legacy data centre infrastructure, the increased construction of new ultra-modern sites and the widespread adoption of more temperature resilient servers has driven a desire for compressor-less cooling, choosing the energy efficient benefits of ambient cooling technologies instead. Why is this happening now? Historically, ambient cooling equipment has been unable to cool data centres to within the right temperature range, which created an industry reliant on refrigerated or compressor led solutions. Now, thanks to more adaptive build methods and the marginal, but vital, increase in server temperature resilience, the temperature parameters of data centres has risen to a range which ambient cooling technology can comfortably achieve. In other words, instead of cooling the compressor, adiabatic equipment is now directly cooling the data centre equipment itself. This is reducing CAPEX expenditure by eradicating an entire chiller from many new build specifications. Why is this a more energy efficient solution? Adiabatic and other ambient cooling equipment achieves lower Energy Efficiency Ratios (EER) than compressor- based chillers. Take the example of a typical compressor chiller which will