Reaping the economic benefits of green data centre efforts


4 March 2014
Reaping the economic benefits of green data centre efforts

The National Library Board has shaved S$55,000 off its annual utilities bill through its green data centre initiatives, and there is still room for improvement as it looks to progressively increase its data centre temperature to further reduce energy costs.

Speaking at the Green Data Centre Journey forum organised by the Infocomm Development Authority of Singapore on 27 February, Mr Ramachandran Narayanan, Deputy Director, Technology & Innovation Division, National Library Board (NLB), recounted how NLB embarked on its first green data initiatives in May 2009 and worked towards compliance with the Singapore Standard for Green Data Centres (SS 564), which it achieved in March 2011, making it the first public agency in Singapore to do so.

The journey involved a gamut of green IT initiatives including the adoption of best practices for data centre design and consolidation, server virtualisation, and improved tracking and monitoring of data centre metrics. Through these efforts, NLB improved its power usage effectiveness (PUE) score from 1.7 before certification to between 1.55-1.63 (in September 20 13 and March 2013 respectively).

PUE measures how much energy is consumed by computing equipment in the data centre compared with cooling and other overheads and has an ideal score of 1.

There was also a general reduction in power consumption by ICT equipment since the green data centre measures were implemented, from 110-115 kW/day in March 2011 to 85-90 kW/Day in March 2013. This came about despite an increase in the ICT workload. For example, NLB’s storage utilisation has grown four-fold from 200TB to about 800TB, without a corresponding increase in ICT power consumption.

Virtualisation and consolidation were the key factors that helped rein in energy consumption, said Mr Ramachandran. With multiple virtual machines running on fewer physical servers, less energy was required to run each server workload. At the same time, a reduction in hardware meant that less energy was required for cooling.

This has translated into tangible economic benefits as well. NLB achieved over S$55,000 savings in utilities costs per year (computed based on a rate of 25 cents per kwh), as a result of conforming to the SS 564 standard, said Mr Ramachandran.

As it continues on its green data centre journey, it is looking to further reduce energy consumption through an ongoing effort to raise its data entre temperature progressively, so that less energy will be used in cooling. From 22 degrees at the start of its green data centre journey, its data centre is now operating at 24 degrees, and Mr Ramachandran believes that this can go up even further without any detrimental impact on the data centre’s operations. The main challenge will be to watch out for hot spots, he said. To address this, an extensive network of 60 probes has been deployed to study airflow temperatures at the data centres.

Cooling was also the subject of a presentation by Ethan Lee, Assistant Vice President, Data Centre Facilities Management, 1-Net Singapore, who spoke about the ClimaControl System Adiabatic Cooling (AC) high pressure misting system developed in collaboration with Climatec Corp. They were one of four successful consortiums awarded the Green Data Centre Innovation Challenge by IDA last year.

The ClimaControl System is a bespoke energy efficiency solution that controls ambient temperature through ultra-fine mists which are produced at a pressure of 50-70 bars and act as a medium for heat transfer. The system was commissioned in June 2013. An energy audit found that between then and September 2013, 1-Net was able to achieve 9.4 per cent in power savings, without any deterioration in temperature.

The third presentation at the forum was on Data Centre Infrastructure Transformation. Mr Kenny Sng, Regional Solution Architect Team Leader, Asia Pacific, Intel Corporation, spoke about “ongoing stress” in data centre operations, such as the long lead time needed to provision new network services, the expected growth in storage demand, and low server utilisation rates. A software-defined infrastructure could help address these issues by transforming physical, discrete network storage and computer resources into flexible virtual pools, he said.