Design and 4E analysis of a solar-driven distributed combined cooling, heating, and power system for zero-energy community

The solar-driven co-generation system can reduce environmental pollution and consumption of primary energy, with various energy demands satisfied. In this study, the demands of a zero-energy community of 50 households in Qingdao are satisfied by designing a hybrid combined cooling, heating, and power (CCHP) system with solar energy as the sole energy input. The system includes the photovoltaic cell, electrolyzer, proton exchange membrane fuel cell (PEMFC), absorption chiller, and the parabolic trough solar collector. With the establishment of the CCHP model, the operation characteristics of the key components, as well as the whole CCHP system, are analyzed. Results indicate that the system can efficiently meet the demands of cooling, heating, and electricity of the community, and the system reaches energy and exergy efficiency of 12.58% and 7.23% in summer, which are 13.06% and 5.48% in winter. The PEMFC achieves energy efficiency and exergy efficiency of 89.72% and 55.47% in summer, and 88.35% and 57.95% in winter. With a design lifespan exceeding 14 years, all investment costs can be recovered by the revenue of the system, and the unit exergy cost will decrease to 0.353 €·kWh−1 after 30 years. Compared to the traditional energy systems, pollution emissions from the CCHP system can be reduced by 99.75%.