The energetic performance analysis of the coupling between the production and distribution of an ice slurry loop

The use of secondary refrigerants in cooling systems is expected to grow significantly for two main reasons: their low production of greenhouse gas emissions and high energy performance. In previous works, we highlighted the interest of the energetic evaluation of a secondary “water/ethanol” loop and developed a physical model for this purpose. Energy consumption of pumps was effectively computed and compared to the amount of cold production. We have shown that, depending on the studied case, this part reveals not negligible on the global performance of the system. The present paper presents a new model which integrates the influence of the refrigerant loop and takes into account the compressor consumption in the energy balance. The corresponding model is depicted in detail in this paper, considering the pressure drops, the pumping power consumed to transport the secondary fluid and the power required by the refrigeration system. A parametric study is done by considering different levels of the temperature and the power applications. We also varied the concentrations of ethanol in each case (single or two phases). The study reveals the existence of an optimal mass flow rate in each case, leading to a maximum global COP of the whole system.