DCN October 2016 | Page 22

green IT

THE WHOLE PICTURE

Marc Naese of Panduit outlines some best practices to consider for maximising the energy efficiency of a greenfield data centre or for modifying an existing deployment .
Figure 1 – Approximate data centre energy cost breakdown by source (%)
Cooling 33 %

After a period of rapid growth , energy consumed by data centres seems to have stabilised at an estimated two per cent of global energy use . Despite the stabilisation , pressures to continually lower operating expenses and reduce environmental impact make data centre energy use a significant area of concern . Growth in data creation , processing , transport and storage continues unabated . More IT operations are migrating to large , centralised data centres or are hosted

Other 14 %
IT 53 %
* Data source : Lawrence Berkeley Labs , 2014 PUE for Midtier data centres , published 2016 . at cloud data centres . These larger sites take advantage of economies of scale and justify improvements in operational efficiencies to demonstrate to their community that they are forward thinking and environmentally responsible .
Optimised energy strategy Whether their data centre is large or small , facility managers need a strategy to most effectively optimise energy consumption . Data centre energy consumption typically breaks down as shown in Figure 1 .
Minimise IT power The first step in optimisation of data centre energy consumption should be to minimise the energy consumed by the IT equipment itself . Not only is this the largest cost segment , it is also a contributing factor to all of the other energy costs needed to run the data centre . Practically every Watt used by IT equipment ultimately turns into waste heat that has to be removed from the facility . As a result , any reductions in IT power consumption are compounded , reducing total energy costs .
Orphaned IT equipment , which is drawing power but doing nothing productive , is a great starting point . Eliminating it frees up facility space , power and cooling capacity . The challenge to data centre managers is in knowing confidently which physical equipment is actually sitting idle . Established operations with years of evolution may require data centre infrastructure management tools and / or significant analysis to gain a clear picture of the physical locations of orphaned IT equipment .
Underutilised IT equipment is another opportunity to reduce a data centre ’ s energy footprint . Several servers operating well below capacity will consume more energy than a single server running near full capacity . Industry trends support migration of operations to virtualised environments . Many virtual machines can be custom sized for the applications they will be running . These can reside on a single , high capacity server that will use much less energy than if each application was on its own physical server . Converged systems combine compute , storage , networking , virtualisation software , power distribution and interconnectivity into a pre-packaged cabinet or multiple cabinets , simplifying the deployment of high capacity environments .
Power Usage Effectiveness , or PUE , is a commonly used metric for calculating data centre power efficiency .
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