Thin-film multijunction solar cells have the potential to meet the performance and cost requirements for grid-connected power generation. At present, multijunction amorphous silicon solar cells have exhibited stabilized conversion efficiencies of about 10% in the laboratory, and large-area modules of comparable performance should be available commercially by the mid-1990s. Further improvements in the properties of amorphous silicon alloys should lead to even-higher-performance multijunction modules in the late 1990s with manufacturing costs of less than U.S.$0.50 W(p)-1.