Abstract
Seafood plays an important role in the local food supply chain, especially in coastal areas of low- and middle-income countries (LMICs). Maintaining proper product temperature throughout the cold chain is essential for preserving seafood quality and reducing food waste. However, small fishing vessels often lack active refrigeration, relying only on ice to preserve the catch. This study investigates the potential of a compact transcritical CO₂ refrigerated seawater (RSW) system as an alternative. Experimental investigations with seawater inlet temperatures from 20 °C to 30 °C, typical for warm climate regions in LMICs, showed COP values from 3.5 to 1.8. To address the low values at high temperatures, an economizer was integrated. This enabled vapor injection. The results showed an improved performance by up to 6.7 % resulting in a COP of 2.07. A Modelica model was developed to simulate various operating conditions and configurations. Simulations for Norwegian conditions showed less than 1.5 % efficiency increase and limited benefit from vapor injection in colder climates.