To reduce the energy consumption of a CO

2

ice-making system and improve system performance

this study proposes a transcritical CO

2

two-stage compression ejector expansion direct cooling ice-making system with complete intercooling (TCEIS). The effects of key parameters on system performance were analyzed by developing a thermodynamic model. Using this model

the COP

R+HR

annual power consumption

heat recovery capacity

annual operating cost

and heat recovery income of the system applied in different seasons and cities were evaluated and compared with those of a two-stage compression direct cooling ice-making system (TCS)

a two-stage compression direct cooling ice-making system with complete intercooling (TCIS)

and an ejector expansion direct cooling ice-making system (ES). The results show that TCEIS has the highest COP

R+HR

considering heat recovery

with the advantages being noticeable in hot seasons and cities. When operating in Guangzhou with cooling loads of 410.989 kW in winter

542.092 kW in transition seasons

and 701.353 kW in summer

the annual operation cost of TCEIS can be reduced by 107.6 thousand yuan

397.9 thousand yuan

and 583.1 thousand yuan compared with those of TCIS

TCS

and ES

respectively. This study provides a theoretical reference for the construction and application of CO

2

direct-cooling ice-making systems.