Development and assessment of the performance of a novel parabolic trough solar collector driven three-stage cooling cycle

A gaseous flow is employed as heat transfer fluid (HTF) in a parabolic trough solar collector (PTSC) for simultaneous production of cooling at three different levels of temperature to meet the demands of air conditioning, refrigeration, and ultra-low temperature refrigeration required to ensure the efficacy of some special vaccines. The combined system consists of five subsystems including PTSC, Kalina cycle, ejector refrigeration cycle (ERC), cascaded refrigeration cycle (CRC), and absorption refrigeration cycle (ARC). A simulation through Engineering Equation Solver (EES) is conducted to assess the impact of internal tube diameter of absorber and solar irradiation on rise of HTF temperature and mass flow rate of Kalina cycle fluid. It is determined that for given solar irradiation, temperature of HTF goes down when internal diameter of absorber tube is enlarged. The influence of weather conditions; solar irradiation and ambient temperature, type of HTF, and concentration of ammonia-water basic solution on thermal and exergy efficiencies of three-stage cooling cycle (TSC) are examined. The TSC with helium operated PTSC deliver better results than air and CO2. Exergy analysis show that solar collector (30.26%) dissipates the highest exergy, followed by ejector (12.5%) and VGSS (7.61%). Type of CRC fluid-pair affect TSC cycle refrigeration capacity, and cooling exergy efficiency. Promotion of solar irradiation from 850 to 1200 W/m2 increases the cooling exergy efficiency of three-stage cycle from 6.72% to 9.52% when evaporator temperature is set at −45°C and CRC employs NH3-propylene.