Ecolibrium. Cloud control. Keeping data centres cool. OCTOBER 2018 VOLUME 17.9 RRP $14.95 PRINT POST APPROVAL NUMBER PP352532/00001

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1 Ecolibrium OCTOBER 2018 VOLUME 17.9 RRP $14.95 PRINT POST APPROVAL NUMBER PP352532/00001 Cloud control Keeping data centres cool.

2 22 ECOLIBRIUM OCTOBER 2018

3 The hunter and the prey A clever modernisation project has reinvigorated an aging mission-critical data centre in Sydney into a state-of-the-art facility. As Sean McGowan reports, the designers of the award-winning HVAC system embraced displacement ventilation, with cool air effectivelyseeking out or hunting down if you will the warm air and driving it out. OCTOBER 2018 ECOLIBRIUM 23

4 The Processing Centre had a touch-up of its looks as well as its efficiency. In an era when giant new data centres are being built around Australia to serve our ever-increasing demand for data storage and processing, owners and operators of existing, aging facilities are facing a tough decision. Should they abandon them, or commit to refurbishment? But can aging facilities be sufficiently transformed to achieve the same levels of performance, reliability and security as their modern counterparts? An important data centre operating in Sydney for a major Australian financial institution has answered this question in the affirmative, after a major modernisation project designed and managed by The Frame Group breathed new life into the 28-year-old facility. In doing so, the data centre s operational life has been extended by another 20 years while underpinning the availability of client services to customers. RISK VERSUS REWARD Built in 1985 to accommodate mainframe computer equipment and processing systems no longer in use today, the data centre is home to the company s critical enterprise services. These support highly critical, client-facing operations. In need of refurbishment to ensure these operations could continue, a major modernisation project was approved. The aim was to transform vacant office space on Level 2 of the building into a new data centre to house the client s server requirements. This new space would be alongside the five existing data halls dispersed throughout the building, so as to create space to migrate into without affecting the critical operations. But with the majority of the facility s existing building services approaching the end of their serviceable life, there was also a requirement to refresh or replace this equipment. If this was successful it would extend the building infrastructure s operational life by at least another 20 years. And it all had to be completed without impacting on the ongoing 24/7 critical operations of the data halls. The project required the installation of brand new, highly efficient plant and equipment in a live data centre environment, which could not be interrupted, says The Frame Group s head of critical facilities, Greg Jackson. What made it all the more challenging was the requirement to deliver the project within a tight timeframe, to a specific budget and to provide a design that could be installed within the existing building One of the project s key objectives was to... achieve a PUE of less than 1.3 across the entire site alongside existing services, such that no downtime to existing services was experienced. As well as transforming Level 2 of the building into a new data centre, the modernisation of the facility had other requirements. It needed to upgrade all of the engineering services associated with new office spaces, meeting rooms, amenities, front-of-house, security and external areas. The refurbished data centre was also required to accommodate current and future IT requirements. One of the project s key objectives was to deliver a mechanical and electrical design that would achieve a power usage effectiveness (PUE) of less than 1.3 across the entire site for the new infrastructure. 24 ECOLIBRIUM OCTOBER 2018

5 Structuring the project around its design management responsibilities for all disciplines, The Frame Group set about developing a solution that would meet the design brief without exposing the client to design and construction risks. TRADITION DECONSTRUCTED The Frame Group adopted a holistic approach to the refurbishment and modernisation of its client s facility. Underpinned by the firm s mechanical displacement ventilation philosophy, The Frame Group s re-imagining of the 22,000m² facility has given the client new data hall spaces. These have enabled simple and seamless migration, and consolidation from legacy systems to new. Jackson says the design undertaken in BIM deconstructed the traditional data centre topology and re-assembled it. The objective was to provide a simpler, more reliable model that requires less plant space and energy to run. About 2,700m² of technical space has been divided into three new data halls, supporting 2900kW of IT equipment. These halls are served by a displacement cooling solution that introduces lowvelocity air to the space via large grilles located in the front of specially designed, low-velocity fan units integrated into the walls of the data hall. This design removes the need for a supply-air plenum. Rows have been arranged in hot and cold aisles. The IT equipment is arranged in rows with an aisle between each, and rows arranged in hot and cold aisles. The room forms a cold aisle, while hot aisles are contained with spring-closed hot aisle end doors. Either the complete aisle is ducted to a ceiling plenum, or individual racks are given hot air chimneys for hot air return to CRAC (computer room air conditioning) units.

6 MULTI-AWARD WINNER As well as being the winner in the Best HVAC Retrofit or Upgrade category at last year s AIRAH Awards, the project was recognised as the Best Data Centre Transformation in the Data Centre Dynamics APAC 2016 awards. It also took home three Architecture Institute of Australia Awards under the categories of commercial, sustainability and interiors. The major driver of displacement ventilation is to effectively remove heat and contaminants from the cooling zone and collect it at high level, where it is then extracted from the space, says The Frame Group s engineering design manager, Arsalan Shahlaee, M.AIRAH. Individual racks are given hot-air chimneys.

7 Utilising this design, Shahlaee says the heat effectively becomes the prey and the cool air the hunter, as the cool air effectively seeks out the warm air via the convection process. With the chimney effect created, directing the hot air to the ceiling plenum by the hot containment at the rear of the rack, the higher the equipment temperature the larger the quantity of cool air is drawn inside the racks, he says. In this way, the air distribution is perfectly uniform, thus preventing any mixing. According to The Frame Group, the displacement method was considered superior to traditional up-flow or downflow systems for the application of this data centre. One advantage is that it allows for mixed rack capacities such that very hot racks with high power densities can be distributed throughout the rooms without special consideration needing to be given, nor degradation of cooling performance and effectiveness. Another is that the temperature distribution inside the racks and within the room remains uniform under all working conditions, having been made independent of any variation in the racks and room thermal loads. The new data halls have a fully contained process cooling system that exceeds Tier III redundancy and resilience requirements meaning that the cooling system is mechanically fault tolerant and the operation will remain intact should there be an issue with multiple units, says Shahlaee. The cool supply air and warm return air is segregated so that they do not mix and create inefficiencies. With stratification of the air granting a return-air temperature to the room unit higher than the values achieved with traditional systems, a number of benefits are realised. These include higher plant efficiencies, an improved PUE ratio due to the substantially higher cooling capacity and savings in central plant running costs as a consequence of the elevated water temperatures used (15 C compared to 8 C common of traditional systems). Additionally, the system designed for the facility required 20 per cent less airflow. This has resulted in a considerable reduction in fan energy consumption, and lower noise emissions. Displacement units also allow for a sensible reduction in installation costs, by matching room loads with less room units, says Shahlaee. The displacement units are typically cheaper per unit than traditional down/up blow CRACs. About 32 low-velocity precision displacement fan units have been installed in each new data centre, providing N+4 redundancy based on the unit groupings.

8 But quite often, the industry pushes back on innovation and new approaches outright without considering the alternative due to the fact that there is a perception that the new approach is not in line with the industry practice in Australia, says Shahlaee. We have proven in this project that you can explore other options whilst delivering highly efficient and reliable systems. Since completion, the modernised data centre has operated to expectation. The chillers have been customised to minimise operational noise levels. LOW-NOISE CHILLERS The mechanical services installed in the modernised data centre consist of a new chiller plant on the building s roof, CRAH (computer room air-handler) units for data hall cooling, AHUs for data hall and node room pressurisation and humidity control, and FCUs for node room temperature controls and power train room temperature controls. Relief air from the ground floor is also provided to power train rooms. In total, over 3.6MW of cooling capacity has been delivered to the refurbished facility via seven new, external adiabatic hybrid air-cooled chillers configured in an N+2 arrangement for redundancy. To ensure the optimal operation of the electrical and mechanical services plant, a site-wide distributed control system (DCS) was deployed that uses industrial control techniques. The DCS is also used to control chiller sequencing to ensure the most economic chiller plant operating scenario is considered. Each of the seven 718kW chillers that make up the plant has also been customised to minimise operational noise levels. The building is surrounded by recent apartment developments, says Shahlaee. This has driven a reduced target noise level for the design, with evening and night-time noise levels now critically important, as apartments are situated above and nearby the data centre. A decision was made to deploy modern centrifugal compressor chillers with free cooling units, very-low-noise fans, acoustic baffles and advanced acoustic management controls. Noise is further reduced through the use of an active dynamic noise control feature that actively adjusts the chiller performance to use a controlled noise mode during set noise limit periods based on programmable time bands even if this results in lower efficiency. From an operational perspective, the chillers can also be controlled, with priority of acoustic noise levels over cooling performance around different time zones, says Shahlaee. The chiller management system is also able to provide cooling performance optimisation based on strategic demand control of the available chillers as a compressor pool. The alternative is to have any one chiller reach 100 per cent load while others are at low load or off. To maximise the use of free cooling in the data halls, the system uses elevated chilled water temperatures. The use of larger chilled water pipes has minimised pumping power. The new plant and cooling solution has been coupled in a way that has not been undertaken before in Australia, says Jackson. EMBRACING INNOVATION The Frame Group says the successful modernisation of this data centre is proof positive that smart design using existing technologies can be effective. None of the technologies applied are new. Rather, they are proven technologies that have been used in countless applications for many years. We now have significant data but this won t be fully justified until the loads in the new spaces are increased, and these are reliant on other client projects that are currently in flight, says Jackson. When loads grow, it is expected that the project will be fully assessed for a NABERS Data Centre rating. PROJECT AT A GLANCE The personnel Design manager: The Frame Group Mechanical services engineer (CRAH, Chillers, CFD): The Frame Group Controls: Zi-Argus Electrical engineer: AECOM Mechanical services contractor: FDC Mech Mechanical services engineer (Other): AECOM Structural engineer: Bekkar Architect: Genton Builder FDC The equipment AHUs: Munters BMS: Tridium Chillers: Geoclima CRACs: RcGroup Diffusers: Airfoil Fans: Pacific HVAC FCUs: Mitsubishi Electric Pumps: Masterflow (Source: The Frame Group) 28 ECOLIBRIUM OCTOBER 2018