This study presents the attempt made to develop an ideal equivalent system for adiabatic expansion type thermal pumps found in the literature. The purpose of developing the ideal system is to investigate the maximum achievable performance of such systems irrespective of the system sizing and pump design adopted and obtain a characteristic efficiency. An ideal system was developed and analyzed. Then the system performance was compared with literature data, which was found to be reasonable. The comparison of the ideal performance of such systems with existing cycles revealed that the efficiency of such types of pumping systems is limited.
Keywords: solar-thermal; thermodynamic cycle; unconventional pumps; water pumping