HP ML150 Optimizing facility operation in high density data center environment - Page 12

requirements of the target servers. Liquid-cooled racks are ideal for high density head loads. The HP Modular Cooling System (MCS), pictured in Figure 6, is one such rack. It is a closed-loop cooling system mounted on an HP 10000 Series G2 Rack. The MCS makes it possible to achieve hardware densities and power consumption levels (up to 35 kW in a single rack) that have been difficult-if not impossible-to support with conventional HVAC systems. In particular, the MCS allows data centers to resolve specific hot spot occurrences without revamping the overall infrastructure or introducing additional heat into the data center. Figure 6. HP Modular Cooling System An HP 10000 Series G2 rack with an attached MCS requires approximately 1½ times the width and 1¼ times the depth of a standard server rack (to allow for the fan and heat exchanger modules and front and rear airflow). However, one MCS enclosure has enough cooling capacity to support the heat load of a rack of equipment consuming 35 kW. This heat load is equivalent to that generated by three 10-kW racks, yet the MCS occupies 40 percent less floor space than three standard racks. Likewise, the MCS supports a heat load equivalent to 4.38 8kW racks (35 kW/8 kW per rack = 4.38 racks) while occupying 65 percent less floor space and reducing the overall heat load on the facility.5 Efficient practices for facility-level power and cooling In the past when data centers mainly housed large mainframe computers, power and cooling design criteria were designated in average wattage per unit area (W/ft2 or W/m2) and British Thermal Units per hour (BTU/hr), respectively. These design criteria were based on the assumption that power and cooling requirements were uniform across the entire data center. Today, IT managers are populating data centers with a heterogeneous mix of high-density hardware as they try to extend the life of their existing space, making it important to understand power density distributions across the facility. 5 Complete product information for the HP Modular Cooling System may be found at: http://h20000.www2.hp.com/bc/docs/support/SupportManual/c00600082/c00600082.pdf 12