Passive cooling at a Dublin data centre
Thu 21 Jul 2016
Radical ‘free’ cooling unlocks IT potential at Profile Park in Dublin, an innovative solution that could keep the fast growing world of data on track…
Digital companies are under intense economic pressure to rapidly expand the IT capacities in their data centres in the face of soaring global demand for their services. This has major implications for energy consumption and methods for maintaining optimum working temperatures for equipment.
Allowing IT firms to expand their operating space without losing control of the energy costs and keeping data management systems working efficiently is an increasingly pressing challenge for the engineers designing these buildings. Therefore, a BREEAM ‘Excellent’ project commissioned by a leading global data management firm has important lessons for the whole industry. The project envisions ‘free cooling’ as essential to the future economic model of the data management industry.
Profile park, Dublin
The proving ground is the Profile Park centre in Dublin, whose BREEAM ‘Excellent’ rating is the result of a partnership with Excool. The centre relies on indirect adiabatic and evaporative cooling system to exploit free cooling for extended periods, but without exposing the sensitive equipment to untreated, outside air. The Excool system uses outdoor air to cool the indoor air via a heat exchanger.
When the outdoor temperature is high the adiabatic and evaporative process lowers the outdoor temperature sufficiently so that free cooling is always available. The Irish climate is ideal for providing long periods of free cooling to keep the equipment rooms at optimum operating temperatures at very low energy consumption.
Most data centre companies now focus on the power usage effectiveness (PUE) system developed by The Green Grid to measure the energy efficiency of their facilities. The Profile Park site in Ireland now provides 15.4MW of IT provision from four buildings at an extremely impressive PUE of 1.2 with no compressor-based cooling.
Leveraging the environment
The facility is the first one in Ireland to receive the Uptime Institute’s TIER III classification for both design and facility. It also received the Institute’s prestigious BRILL award for product solutions last year along with its BREEAM rating.
Each building contains two data hall modules rated at 1.92MW, which can be sub-divided into two 960KW modules without loss of performance or resilience. Most of the year, the heat in the data hall is simply transferred via the plate heat exchangers to the cooler outdoor air. The two air streams are separated to make sure the indoor air is free of contaminants from external pollution.
During some summer periods, the Excool adiabatic system maintains the supply air temperature of 24°C by saturating the outdoor air and raising the relative humidity to 100%. This lowers the temperature to a point where it can still meet the target indoor conditions.
The maths behind the savings
The annual energy savings have been calculated at €650,000 per 1920kW hall based on similar sites that achieve a benchmark of around 1.6 PUE.
This solution has, considerable potential for capital and maintenance cost savings on top of the impressive cuts in energy use and carbon emissions. It also proves that it is possible to successfully cool intensively used data centres using a ‘passive’ approach – a discovery which could have major implications for the building engineering sector.