This presentation shares CERN Cryogenics Group’s experience in the design, operation, maintenance, and long-term sustainability of large-scale helium refrigeration systems. CERN currently operates around 30 independent cryogenic installations supporting accelerators, detectors, and test facilities, with a total refrigeration capacity of approximately 180 kW equivalent at 4.5 K and accounting for an electrical consumption representing a quarter of CERN’s annual consumption.
The cryogenic system for the Large Hadron Collider (LHC), where reliability and availability are critical, achieves availability levels above 98%, while optimizing both helium and electricity consumption. Operational excellence is supported by continuous operator training, advanced automation, simulation tools, and digital twins. Maintenance activities combine predictive, preventive, and corrective strategies, with shutdown periods dedicated to scheduled maintenance, system consolidation, and upgrade projects.
The long-term success of LHC operations and its outstanding physics achievements have enabled the transition to the High-Luminosity LHC (HL-LHC) upgrade, currently under installation and planned for operation until the early 2040s. Beyond this period, the Future Circular Collider (FCC) could succeed the HL-LHC, capitalizing on CERN long-term expertise in large-scale helium refrigeration systems.
 

Keywords
Operation|maintenance|sustainability