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• ORC and compound ejector-multi evaporator vapour compression systems are combined. • Nine ultra-low global warming potential refrigerant pairs are proposed to replace R134a and R245fa. • Condenser waste heat recovery increases the overall coefficient of performance. • The pair R1234ze(Z)/R1234ze(E) results in the highest energy performance. This article evaluates the energy and exergy performance of a novel dual fluid combined organic Rankine-compound ejector multi evaporators vapour compression system (ORCEMES) for power, cooling and heating purposes. Six working fluids with ultra-low global warming potential: R1234ze(E), R1243zf, R1234yf for the CEMES and R1234ze(Z), R1336mzz(Z) and R1224yd(Z) for the ORC were selected, resulting in nine combinations. The system can work in two operating modes: power-cooling and power-heating modes. The combination of R1234ze(Z) and R1234ze(E) results in the highest overall system energy performance. The proposed system increases power generation from 21% to 75% at high geothermal and low geothermal temperatures, respectively, compared with separated basic ORC and multi-evaporator systems at the same operating conditions and cooling capacity. The proposed CEMES reduces compressor power consumption to 85% of the basic system, increasing COP remarkably. Concerning the exergy analysis, the low-temperature recapture heat exchanger shows the highest exergy destruction compared to the rest of the components, followed by the turbine. Besides, the second expansion valve presents the lowest exergy destruction percentage. [ABSTRACT FROM AUTHOR]