Integrated thermal storage and heat recovery of the CO₂ refrigeration system for fishing vessels

The natural refrigerant CO₂ is gaining an attraction for fishing vessels due to its compact units, negligible global warming potential (GWP), and non-toxic behaviour. Chilling and freezing onboard are energy-consuming processes but are necessary to ensure high-quality products. Cold thermal storage is a smart feature that assists the refrigeration system at peak loads, and such setups are working efficiently on the onshore facilities. CO₂ thermal storage is suitable for fish freezing with which you can store cold energy as low as -57 °C. Heating is also necessary onboard, for warm water, snow melting, and processing of fish rest raw material. Currently, the onboard refrigeration system challenges are low coefficient of performance (COP) at part load operations and insufficient capacity at peak loads. This paper investigates the integrated CO₂ thermal storage and heat recovery from the gas-cooler of the CO₂ refrigeration system to improve the total system performance.