CooLMUC-2: A supercomputing cluster with heat recovery for adsorption cooling

In High Performance Computing (HPC), chiller-less cooling has replaced mechanical chiller supported cooling for a significant part of the HPC system resulting in lower cooling costs. Still, other IT components and IT systems remain that require air or cold water cooling. This work introduces CooLMUC-2, a high-temperature direct-liquid cooled (HT-DLC) HPC system which uses a heat-recovery scheme to drive an adsorption refrigeration process. Using an adsorption chiller is at least two times more efficient than a mechanical chiller for producing needed cold water. To this date this is the only installation of adsorption chillers in a data center combining a Top500 production level HPC system with adsorption refrigeration. This prototype installation is one more step towards a 100% mechanical chiller-free data center. After optimization of the operational parameters of the system, the adsorption chillers of CooLMUC-2 consume just over 6kW of electrical power to not only remove 95kW of heat from the supercomputer, but also to produce more than 50kW of cold water. This paper presents initial measurements characterizing the heat-recovery performance of CooLMUC-2 at different operating conditions.