Potential of applying the thermochemical recuperation in combined cooling, heating and power generation: New concept and energy analysis

Employing combined cooling, heating and power (CCHP) production in the distributed energy network is a sustainable pathway to realize efficient energy conversion. In this work, the method of thermochemical recuperation (TCR) is introduced and integrated into the typical CCHP system, in order to further enhance the waste heat recovery and coordinate the system multiple energy output characteristics. Different from the direct thermal recovery, the high-temperature exhaust gas heat from the prime mover firstly drives the endothermic reactions, which is also readily stored in the chemical form and supports the subsequent CCHP production. The system thermodynamic performances are comprehensively investigated under various operation conditions. The results indicate that considerable irreversible loss during the chemical fuel utilization can be reduced, and the system power efficiencies are improved by 13.72-21.55% and 3.87%-17.16% for the gas turbine (GT) and the internal combustion engine (ICE) under the designated scenarios, respectively. Furthermore, diverse endothermic reactions are adopted to evaluate the practical application feasibility, and relatively stable and effective exhaust heat recuperation will be realized for the GT-based system off-design operation. Regarding to the ICE condition, the qualified exhaust waste heat will be completely recovered by the TCR process and then achieves the fuel saving ratio of 0.24%-14.64%, as well ensures the system operation stability and flexibility. Through the system evaluation, the method of TCR process provides an alternative way to enhance the efficient waste heat recovery and flexible operation for the CCHP production.

Automated summary

This study introduces the method of thermochemical recuperation (TCR) and integrates it into a typical CCHP system, aiming to enhance waste heat recovery and improve system power efficiencies. The results show that TCR can reduce irreversible loss and improve power efficiencies under different operation conditions.