Diseño de sistema de calentamiento de agua usando ciclo de refrigeración compartido para un hotel

Abstract

In this project, a system is designed to recover heat from the discharge line of an R134a refrigeration cycle to preheat domestic hot water, with the aim of reducing the energy supplied by the primary heater. The hypothesis is that the residual heat can be utilized without affecting cold-room operation, and the integration is justified by the simultaneous demand for refrigeration and hot water. For the project development, the components were selected and a coaxial heat exchanger was sized together with a 250 L storage tank. The evaluation was carried out through a 24 h transient simulation in MATLAB, where consumption profiles and load variations were represented. The results showed a discharge temperature close to 80 °C, a recovered heat rate of 0.67–1.66 kW, and a tank temperature between 30 and 40 °C, reducing the energy required by the heater compared to the case without heat recovery. It is concluded that the system is technically feasible as a preheating stage and that its economic attractiveness depends on the incremental integration cost and on optimizing operating conditions. Keywords: heat recovery, R134a, coaxial heat exchanger, domestic hot water. Keywords: Energy efficiency, heat recovery, heat exchanger, sustainability, refrigeration cycle.