Proposal and thermoeconomic evaluation with reliability considerations of geothermal driven trigeneration systems with independent operations for summer and winter.

• Thermoeconomic analysis of two novel geothermal driven trigeneration systems is presented. • The systems are developed to operate in complete CHP or CCP modes independently. • The systems can be simply switched between summer and winter modes. • The levelized product cost of System II is 28.51 $/GJ for summer application mode • The proposed systems perform better than the available similar ones in the literature. Novel tri-generation systems are developed to operate in a complete CHP or CCP mode, with having relatively simple configuration to meet a cost-effective design. The system consists of conventional Rankine and ejector refrigeration cycles in which CO 2 is used as the environmentally-friendly working media (System I). To enhance performance of the proposed System I, a modification is made by incorporation of an internal heat exchanger to form the System II. Thermoeconomic performance of the systems are evaluated and optimized based on levelized cost of system products. Also, the reliability of the proposed systems are evaluated and discussed. It is found that, the proposed System II has exergy efficiency and levelized product cost of 39.68% and 28.51 $/GJ, for summer application mode. The results also indicated that at optimal operating conditions, System II has lower levelized product cost than System I by 10.4% and 2.3%, besides it has higher exergy efficiency than System I by 11.4% and 4.0%, for summer and winter modes, respectively. However, for winter applications, System I performs better than System II in terms of heating output and thermal efficiency by 97.3% and 34.1%, respectively. The results demonstrated that, the proposed systems offer opportunity of selecting a suitable one depending on the user's energy (power, cold or heat) demand. [ABSTRACT FROM AUTHOR]