Experimental investigation on a 3Â kW organic Rankine cycle for low-grade waste heat under different operation parameters

The experimental study of a 3 kW organic Rankine cycle (ORC) system using an open-drive scroll type expander and R245fa has been investigated. The expander is originally hermetic-type refrigerant scroll compressor with built-in volume ratio of 3.24. The effects of pressure drop, degree of superheating and condenser temperature on system overall performance are examined. Moreover, the detailed behavior of pump and expander are explored. The experimental results show that the pressure drop exhibits a relatively higher sensitivity on system performance. The condenser temperature exhibits a negative effect on electrical power, thermal efficiency and system generating efficiency. The maximum expander shaft power, electrical power, thermal efficiency and system generating efficiency are 2.64 kW, 1.89 kW, 5.92% and 3.93%, respectively. The highest thermal efficiency does not represent the highest expander shaft power.