FACILITIES power+cooling
inherently resilient system was provided due to less potential points of failure, along with a reduced carbon footprint. Structural support steelwork, plant space and maintenance were also significantly minimised. The main chilled water pumps were provided with inverter frequency drives and these served chilled water to the perimeter CRAC units which incorporated low energy EC fans. These highly efficient fans also formed part of an automatic floor pressurisation system. This ensures that the air pressure within the raised floor remains relatively constant and so minimises any impact on room conditions when floor tiles are lifted for maintenance or data cabling. Conditioned air was supplied via floor grilles in a hot aisle/cold aisle configuration to aid in separation of the airstreams.
The Data Hall ventilation system comprised a heat recovery air handling unit which reclaims the heat from the extracted air and so reduces any heating requirement to temper incoming fresh air to acceptable conditions. Inverter frequency drives were also used on the integral supply and extract fans. The Ancillary rooms were served by a heat recovery VRF air conditioning system and were provided with tempered fresh air via a number of heat recovery ventilation units. These units reclaim the heat energy from the extracted air and use it to heat the incoming fresh air.
To minimise the initial CapEx, fully resilient, scalable, modular UPS systems with a near unity input power factor were specified to match the initial Day 1 anticipated load. This approach allows the expansion of the UPS systems to match the projected IT load increase with minimal disruption to the operational capability of the facility. Total Cost of Ownership (TCO) is always of prime importance and the systems selected were 97% efficient at full load and 96% efficient at 50% load. Within the Support Areas and circulation spaces energy efficient lighting systems using intelligent absence detection systems were provided. These systems reduce the lighting levels in vacated areas to preset levels for a predetermined time before turning them off completely.
The Day 1 Load
As is often the case in new Data Centres, the Day 1 partial room occupancy required only a small percentage of the total room cooling and power capacities. This provided potential for significant energy savings to be made during this initial period. The building management system (BMS) and the LAN networks of the critical cooling system equipment provided the platforms which were upgraded to include a specific time schedule to shut down specified CRAC units when not required. It should be noted that this is a highly simplified explanation of the Day 1 configuration and does not detail changes to setpoints and plant control modes.
Lessons to be Learnt
It is hoped that by this time, readers will appreciate that effective implementation of energy efficient systems is not beyond the reach of most, if not all, organisations. With the exception of the bespoke Day 1 controls upgrade, all of the efficient systems provided in our example are commonly
available.It was also hoped to highlight that the prime mover in the implementation of energy efficient solutions is undoubtedly the Clients undertaking to incorporate such systems.
This decision can, however, be encouraged by optimising the CapEx budget and providing significant energy savings for the benefit of the OpEx. As stated at the beginning of the article, imminent fuel price increases could have a profound effect on the operational costs of running a Data Centre in the very near future so the real question is; “Can anyone afford not to implement the use of energy efficient systems in their Data Centres?”
February 2012 I
www.dcsuk.info 29
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52