TECHNOLOGY FOCUS - CERAMICS AND GLASS - Preferred Component: Each hexagonal light guide comprises a transparent material including borosilicate glass and/or quartz.    TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Component: The battery is nickel-cadmium battery, lead-zinc battery, lithium ion battery, nickel metal hydride battery, zinc-carbon battery, zinc-chloride battery, alkaline/manganese battery, and silver-oxide battery or metal oxyhydroxide battery. The internal solar cell is monocrystalline silicon (Si) internal solar cell, polycrystalline-Si (poly-Si) internal solar cell, amorphous-Si (amorp-Si) internal solar cell, germanium (Ge) internal solar cell, gallium arsenide (GaAs) internal solar cell, Ga indium phosphide (GaInP2) internal solar cell, cadmium sulfide (CdS) internal solar cell, Cd selenide (CdSe) internal solar cell, Cd telluride (CdTe) internal solar cell, copper indium selenide (CuInSe2) internal solar cell, titanium oxide (TiO2) internal solar cell, zinc oxide (ZnO) internal solar cell, tin oxide (SnO2) internal solar cell, tungsten oxide (WO2) internal solar cell, indium oxide (InO) internal solar cell, molybdenum disulfide (MoS2) internal solar cell, Mo diselenide (MoSe2) internal solar cell, or molybdenum ditelluride (MoTe2) internal solar cell. The external solar cell is monocrystalline-Si external solar cell, poly-Si external solar cell, amorp-Si external solar cell, Ge external solar cell, GaAs external solar cell, GaInP2 external solar cell, CdS external solar cell, CdSe external solar cell, CdTe external solar cell, CuInSe2 external solar cell, TiO2 external solar cell, ZnO external solar cell, SnO2 external solar cell, SnO2 external solar cell, WO2 external solar cell, InO external solar cell, MoS2 external solar cell, MoSe2 external solar cell, or MoTe2 external solar cell.    TECHNOLOGY FOCUS - POLYMERS - Preferred Component: Each hexagonal light guide comprises a transparent material including cellulose acetate, cellulose acetate butyrate, cellulose propionate, polyacrylate, polyarylate, amorphous polyamide, polycarbonate, polyetherimide, sulfonated polyether, polyethylene terephthalate, polystyrene, styrene-acrylonitrile copolymer, styrene-maleic anhydride copolymer, polysulfone, and/or polyvinyl chloride.