Economics of Large Helium Cryogenic Systems: Experience from Recent Projects at CERN

Abstract

Large projects based on applied superconductivity, such as particle accelerators, tokamaks or SMES, require powerful and complex helium cryogenic systems, the cost of which represents a significant, if not dominant fraction of the total capital and operational expenditure. It is therefore important to establish guidelines and scaling laws for costing such systems, based on synthetic estimators of their size and performance. Although such data has already been published for many years, the experience recently gathered at CERN with the LEP and LHC projects, which have de facto turned the laboratory into a major world cryogenic center, can be exploited to update this information and broaden the range of application of the scaling laws. We report on the economics of 4.5 K and 1.8 K refrigeration, cryogen distribution and storage systems, and indicate paths towards their cost-to-performance optimisation. ABSTRACTLarge projects based on applied superconductivity, such as particle accelerators, tokamaks or SMES, require powerful and complex helium cryogenic systems, the cost of which represents a significant, if not dominant fraction of the total capital and operational expenditure. It is therefore important to establish guidelines and scaling laws for costing such systems, based on synthetic estimators of their size and performance. Although such data has already been published for many years, the experience recently gathered at CERN with the LEP and LHC projects, which have de facto turned the laboratory into a major world cryogenic center, can be exploited to update this information and broaden the range of application of the scaling laws. We report on the economics of 4.5 K and 1.8 K refrigeration, cryogen distribution and storage systems, and indicate paths towards their cost-to-performance optimisation.

The Cost of Helium Refrigerators and Coolers for Superconducting Devices as a Function of Cooling at 4 K

“…This agrees with cost equations that came from studies at the CERN-LHC in 1999 [9,10]. The largest plants shown in FIGURE 2 are quite complex.…”

U.S. Linear Collider Technology Options Study

“…Models for the cost of cryogenic refrigeration systems have been developed and updated over the years [61,62,63,64,65,58]. These models were based on the actual costs to purchase cryogenic refrigeration systems operating between 4.2 K and 80 K. In order to fairly compare these systems, actual costs were adjusted to a reference refrigeration system.…”

“…B LHC studies with cryogenic industry has shown that a 24 kW (4.5K equivalent) sized plant is the largest for which the LHC Project Report 317 [58] design methodology is applicable.…”

Advanced superconducting technology for global science: The Large Hadron Collider at CERN

“…To cope with its heat loads, the LHC will require eight large helium cryogenic plants, each producing a mixed duty of liquefaction and refrigeration at different temperatures, with an equivalent capacity of 18 kW @ 4.5 K and a coefficient of performance (c.o.p.) of 230 W/W [19]. The coldbox of the first LHC cryogenic plant, presently undergoing reception tests at CERN, is shown in FIGURE 9.…”