ADVANCED HIGH-CONCENTRATION HIGH-EFFICIENCY TANDEM PV ASSEMBLIES

THE PROPOSED THREE-PHASE PROGRAM ADDRESSES THE NATIONAL NEED FOR HIGHLY EFFICIENT PHOTOVOLTAIC ENERGY CONVERSION. IN PHASE I OF THE PROPOSED PROJECT, KOPIN WILL EXAMINE THE FEASIBILITY OF INTEGRATION OF A MONOLITHIC TANDEM CELL (FOR HIGH EFFICIENCY) WITH A CLEFT SUBSTRATE RECOVERY APPROACH (FOR REDUCED COST). OF PARTICULAR IMPORTANCE IS THE DESIGN OF A SIMPLIFIED INTERCONNECT AND HEAT TRANSFER APPROACH TO BE USED WITH THIN CELLS OF THIS TYPE. THE BANDGAPS IN THE MONOLITHIC TANDEM CELL TO BE CONSIDERED ARE 1.43 EV AND 1.9 EV; THE UPPER LIMIT TO THE EFFICIENCY FOR THIS APPROACH IS 34%. PHASE I WILL ALSO EXAMINE THE FEASIBILITY OF STACKING THE TANDEM ON A BOTTOM CELL HAVING A BANDGAP OF ABOUT 1.1 EV, TO OBTAIN CONCENTRATOR EFFICIENCIES OF OVER 40%. IF FEASIBLE, PHASE II WOULD CONSIST OF IN-DEPTH RESEARCH ON THE FABRICATION OF A PROTOTYPE CELL.