Performance evaluation of a polymer electrolyte membrane fuel cell system for powering portable freezer

A polymer electrolyte membrane fuel cell (PEMFC) powered portable freezer has been developed. The PEMFC system is composed of an air-cooled fuel cell stack module with combined oxidant and coolant flow, a fuel supply subsystem with two metal hydride canisters, a power management subsystem with a DC–DC converter and a lead acid battery, and a control electronics subsystem. The vapor compression refrigeration cycle has been adopted for refrigerating. The control logic for fuel cell stack operation, cabinet temperature maintenance and fuel canister replacement has been designed for a stable system operation. To estimate PEMFC system performance, the stack power output, parasitic loss and battery charging power are measured for various external loads. The PEMFC system provides a rated power output of 200.5 W at 13.4 V with balance-of-plant (BOP) efficiency of 72%. The maximum system efficiency based on lower heating value (LHV) is 37% at 120.7 W. The PEMFC powered freezer stably operates with the continuous replacement of hydrogen canisters, and the cabinet temperature drops to −21.8 °C when the ambient temperature is 26.6 °C.