A solar collector (100) is provided having increased efficiency and operating life, and reduced size and cost over conventional collectors. Generally, the collector (100) includes a three-dimensional array (110) of cells (104), including a base-layer (112) and at least one elevated-tier (114) above and separated from the base-layer, so that at least some light passes between cells of the tier to the base-layer. Preferably, the tier (114) includes cells (104) oriented to receive light reflected from the base-layer (112). More preferably, the array (100) is within an enclosure (108) having a bottom-wall (120) and sidewalls (122, 124) that reflect a portion of light incident thereon onto the cells (104). In one embodiment, the cells (104) include types of monolithic cells sensitive to different wavelengths of light, and the collector (100) further includes voltage converters (144) to match voltages from the different types of cells to a common output voltage. Optionally, cells (104) susceptible to damage by ultraviolet radiation are oriented to receive only reflected light.