Sustainable Accelerator R&D

Accelerators are energy-hungry facilities, and also consume a large amount of material resources. STFC's Accelerator Science and Technology Centre (ASTeC) has recently instantiated a Sustainable Accelerators Task Force, with the remit to make accelerators more energy efficient and environmentally sustainable. Several of ASTeC's activities in this area are presented here. We are undertaking a complete lifecycle analysis of accelerators, encompassing each phase of accelerator design, construction, operation, maintenance, and final decommissioning, breaking down each individual subsystem, assessing the facility's overall carbon footprint, and identifying areas where significant savings can be made. The findings are intended to be applicable to a wide range of accelerator facilities; we are using a planned mid-range facility, RUEDI, as a case study.

We also present here some of ASTeC's other R&D towards greater sustainability for the accelerators of the future. The Zero-Power Tunable Optics (ZEPTO) project has developed tunable permanent magnet versions of beamline dipoles and quadrupoles. Work into superconducting thin films for RF cavities has the potential to make significant gains in performance compared to bulk niobium cavities, with operation possible at higher cryogenic temperatures and lower material requirements. Surface treatments of vacuum chambers are being developed: Non-Evaporable Getter (NEG) coatings to improve vacuum performance and reduce the need for pumping, as well as coatings to reduce excess charge build-up and improve beam transport. ASTeC has a world-leading programme of R&D into energy recovery linacs (ERLs) which can greatly reduce the energy in the RF system by recycling the energy of a spent beam. Finally, a feasibility study has been carried out by ASTeC into ground water cooling at the Daresbury site, which would utilise the cooling capacity of water stored in the ground to cool both accelerators and supercomputers located on our site.