Sustainable cooling solutions for data centres with the HXV Hybrid cooler

A sustainable cooling solution with BAC’s HXV Hybrid Cooler reduced water and energy use. This case study elaborates on how implementing the solution improved the efficiency of a 160 MW data centre, resulting in cost reduction and environmental impact.

Data centres often rely on water-cooled chillers combined with open—or closed-circuit cooling towers for heat rejection. Alternative solutions include dry coolers, hybrid fluid coolers, and adiabatic fluid coolers. The study explains how evaluating all heat rejection options helps optimise energy and water usage.

Project

A high-performance computing customer approached BAC with 160 MW operating power to provide a more sustainable cooling solution. They had previously used open cooling towers with water-cooled chillers. BAC collaborated closely with the customer to identify their key challenges and requirements. The primary priorities included minimising water usage while maintaining a balance with energy consumption to align with sustainability goals. Additionally, there was a need to provide efficient cooling for increasing heat loads within a compact footprint. The solution also needed to meet system water temperature requirements without relying on chillers, even under high loads and fluctuating external conditions.

BAC partnered with the customer to understand its challenges and requirements. The focus was on minimising water usage while optimising energy consumption to support the customer’s sustainability initiatives. The solution needed cooling to increase heat loads within a smaller footprint. Meeting system water temperature requirements without chillers at high loads and varying outside conditions was also essential.

Solution

BAC analysed the IT capacity, space requirements, operating power, and location weather data. After that, it evaluated fully evaporative, hybrid, and adiabatic solutions. Based on the analysis, BAC recommended a chillerless system utilising the HXVTM hybrid cooler. The HXV’s packaged evaporative and dry cooling features offered the water-saving and energy-efficient solution the customer desired.

The factory-assembled unit also allowed for easier maintenance and serviceability for the operations team. Due to the crossflow design, large doors, and internal access platforms, they could access the cold-water basin, prime surface coil, and drive system. Additionally, the customer could perform faster inspections of the spray distribution system while the unit was operating.

The HXV Hybrid Cooler addressed all the customer’s challenges and needs, reduced annual energy costs, and improved system efficiency. It helped achieve an estimated power usage effectiveness (PUE) of 1.136.

HXV hybrid cooler

The HXV incorporates three modes of operation. It has the benefits of evaporative, adiabatic, and dry cooling in a water-saving and energy-efficient solution. It maintains peak system performance for various applications where water is scarce, water costs are high, uptime is critical, or plume is a concern. Further, it is an ideal solution where space is limited.

Due to its high dry switch point and extended dry operating hours, the HXV hybrid cooler delivers advantages, including water savings of up to 70 percent compared to open cooling towers. It ensures year-round sensible cooling through its dry coil, further optimising water conservation. On a typical design day, sensible cooling can save an average of 25 percent water. Energy costs are substantially reduced, up to 60 percent lower than air-cooled systems, owing to evaporative cooling combined with BAC’s innovative flow design. The cooler offers improved operational and layout flexibility, balancing water and energy efficiency, while its highest reliability mode eliminates plume abatement. Maintenance requirements are reduced by up to 25 percent compared to traditional fluid coolers, facilitated by their dry operation and crossflow design. Additionally, chemical usage is minimised by up to 70 percent due to its dry operation, making it a cost-effective and environmentally friendly choice.

Result

In this installation, the HXV Hybrid Cooler met the customer’s need for a reasonable first cost while significantly reducing water consumption and operating costs. The HXV heat rejection system offers advantages over open cooling towers with water-cooled chillers. It achieves a remarkable 71 percent reduction in annual water usage effectiveness (WUE), an 86 percent decrease in installed peak power, and a 52 percent reduction in yearly operating costs, encompassing energy and water expenses.

BAC creates cutting-edge cooling equipment for the HVAC, Industrial, and Refrigeration marketplaces. It leverages the power of evaporative cooling by optimising the balance of water and energy.

For more information, visit www.BaltimoreAircoil.com.