Data Center power usage has been growing rapidly as new internet applications are developed, requiring computing resources such as high-density cloud computing server farms. All of the electricity consumed by data centers is ultimately turned into heat. This heat is removed using fans, pumps, chillers and air conditioning equipment, which comprise roughly a quarter of the total data center power consumption.
As part of a US Department of Energy cost shared grant, a data center test facility was designed and constructed with the goal to demonstrate the potential to reduce cooling energy use to less than 5% of the total IT and facilities energy usage by utilizing liquid cooling of the electronics rack. The system was characterized to develop temperature-based energy-aware servo control algorithms for further cooling energy reductions. These algorithms were implemented to dynamically reduce the data center cooling power consumption while controlling to a specified temperature under varying outdoor temperature and workload conditions. This work illustrates the energy-centric controls that were implemented to achieve dynamic system control in the most energy efficient manner.