Thermodynamic Performance Assessment of a Novel Micro-CCHP System Based on a Low Temperature PEMFC Power Unit and a Half-Effect Li/Br Absorption Chiller

The aim of this work has been to evaluate the energetic feasibility and the performances of a novel residential micro-Combined Cooling, Heating and Power (CCHP) system, based on low temperature proton exchange membrane fuel cell (PEMFC) power unit and half effect lithium bromide absorption chiller. This integrated system has been designed to produce both electric, thermal and cooling power by recovering heat from the fuel cell power unit cooling system. The analysis has been conducted by using numerical simulations: the PEMFC power unit and the absorption chiller have been modeled by means of one-dimensional and thermochemical models, respectively, and by means of available experimental and literature reference data, has been performed the validation. The performance parameters such as: the energy utilization factor (EUF), the exergy utilization factor (ExUF) and the trigeneration primary energy saving (TPES), have been used to analyzed the performances of the system. The numerical results showed a good performance in terms of energy and ExUF, in the whole operating field of the trigeneration system. Furthermore, the highest ExUF values are obtained for the minimum evaporator temperature (4 degrees C) and minimum condenser temperature (27 degrees C) of the absorption chiller. The calculated values of TPES for the CCHP mode, ranges from 0.07 to 0.19, thus, the system has good performance in a wide operating range, but the better performance can be achieved at lower loads.