DEVELOPMENT OF METAL HYDRIDE MATERIALS FOR HIGH COEFFICIENT OF PERFORMANCE HEAT PUMPS

THIS PROJECT WILL DEVELOP IMPROVED METAL HYDRIDE MATERIALS FOR A NEW HYDRIDE HEAT PUMP THAT IS ENVIRONMENTALLY CLEAN AND POTENTIALLY TWICE AS EFFICIENT AS THE BEST CURRENT SYSTEMS. NEW THERMODYNAMIC PROCESSES HAVE BEEN DEVELOPED FOR HYDRIDE HEAT PUMPS THAT ARE SIGNIFICANTLY MORE EFFICIENT AND UTILIZE NO CHLOROFLUOROCARBONS (CFCS), WHICH MUST BE PHASED OUT OF USE BY 1995. THE BEST CURRENT REFRIGERATORS OPERATING WITH LESS DAMAGING HYDROCHLOROFLUORCARBON (HCFC) REFRIGERANTS HAVE A COEFFICIENT OF PERFORMANCE OR COP = 1.5, WHILE THE PROPOSED NEW HYDRIDE HEAT PUMP HAS A THEORETICAL COP=3.3. CURRENT RESEARCH HAS DEMONSTRATED THAT HYDRIDE HEAT PUMPS ARE FEASIBLE AND VERY PROMISING, BUT IMPROVED HYDRIDE MATERIALS ARE NEEDED TO ACHIEVE THEIR FULL POTENTIAL. IMPROVED HYDRIDE HEAT EXCHANGERS ARE NEEDED THAT HAVE MORE RAPID HEAT TRANSFER AND HYDROGEN FLOW. HYDRIDES HAVE LOW THERMAL CONDUCTIVITY SO THAT RAPID HEAT TRANSFER INTO AND OUT OF THE HYDRIDE BED IS DIFFICULT. ALSO, HYDRIDE PARTICLES TEND TO BECOME SMALLER AND COMPACTED DURING USE AND THIS BLOCKS THE FREE FLOW OF HYDROGEN INTO AND OUT OF THE HYDRIDE BED. IN PHASE I THE APPROACH TO THE IMPROVED HYDRIDE MATERIALS INVOLVES COATING THE METAL HYDRIDE PARTICLES WITH A THIN LAYER OF COPPER AND THEN COMPRESSING THE COATED PARTICLES INTO POROUS HEAT EXCHANGERS WHICH CAN PROVIDE MORE RAPID AND EFFECTIVE HEAT TRANSFER AND HYDROGEN FLOW. WHEN DEVELOPED, THIS TECHNOLOGY WILL ALLOW NEARLY A 50% REDUCTION IN THE ELECTRIC POWER REQUIRED BY REFRIGERATORS/FREEZERS, AIR CONDITIONERS, AND HEAT PUMPS USED IN BOTH DOMESTIC AND COMMERCIAL APPLICATIONS INCLUDING VEHICLES. THE NEW SYSTEM WILL BE SMALLER, WEIGH LESS, AND COST ABOUT THE SAME AS CONVENTIONAL REFRIGERATION EQUIPMENT. THE SYSTEM DOES NOT REQUIRE CFCS OR HCFCS, SO IT IS INHERENTLY CLEAN AND HAS NO ADVERSE ENVIRONMENTAL IMPACT.