High-performance computing systems like Eagle produce a lot of heat. NREL’s HPC data center cooling system was designed to be super effective in managing that heat—using evaporative towers that are more efficient and less expensive than energy-demanding chillers. However, the towers consumed approximately 2.5 million gallons of water annually to support cooling of the IT load—approaching an hourly average of 1 megawatt. NREL recognized the need to make the data center not just energy efficient, but water efficient, too.
NREL’s David Sickinger, Roy Fraley, and Kevin Regimbal, along with partners from Johnson Controls and Sandia National Laboratories, installed the thermosyphon hybrid cooling system on the roof of the Energy Systems Integration Facility. In combination with the existing evaporative towers, this advanced dry cooler that uses refrigerant in a passive cycle to dissipate heat—called a thermosyphon—forms an extremely water- and cost-efficient hybrid cooling system.
The system saved 1.16 million gallons of water in its first year of operation, cutting the data center’s onsite water usage in half while continuing to operate at optimal energy efficiency. The NREL team received 2018 U.S. Department of Energy Federal Energy and Water Management Awards for this outstanding achievement in energy and water efficiency and conservation.