NOVELTY - The solar cell assembly comprises laterally arranged multiple bandgap (LAMB) solar cells and a dispersive concentrator. The concentrator is positioned to provide light to surfaces of each of the LAMB cells, and is disposed between the LAMB cells. One of the solar cells comprises an n-contact, a p-contact, and an intrinsic alloy layer that is disposed between the n-contact and the p-contact and comprises spatially-composition graded nanowires. Each spectrally selective holographic planar concentrator is present in optical communication with solar cell of each LAMB cell.    USE - Used as a solar cell assembly.    ADVANTAGE - The solar cell assembly can be economically manufactured with high performance, less material consumption and long lifespan.    DETAILED DESCRIPTION - The solar cell assembly comprises laterally arranged multiple bandgap (LAMB) solar cells and a dispersive concentrator. The concentrator is positioned to provide light to surfaces of each of the LAMB cells, and is disposed between the LAMB cells. One of the solar cells comprises an n-contact, a p-contact, and an intrinsic alloy layer that is disposed between the n-contact and the p-contact and comprises spatially-composition graded nanowires. Each spectrally selective holographic planar concentrator is present in optical communication with solar cell of each LAMB cell. The solar cells, which are present in communication with each spectrally selective holographic planar concentrator, have same bandgap, where wavelengths of light selected by each spectrally selective holographic planar concentrator correspond to the bandgap of the solar cell. Each of the solar cells has a bandgap of 0.5-3 eV. The n-contact comprises an n-cadmium sulfide, n-zinc selenide or n-zinc sulfide layer. The p-contact comprises a p-zinc telluride, p-cadmium telluride, p-silicon, or p-germanium layer. One of the solar cells further comprises a heterojunction p-i-n junction. The nanowires include cadmium lead sulfide n-doped (CdxPb1-xS) nanowires, n-doped zinc cadmium mercury telluride (ZnxCdyHg1-x-yTe) nanowires, n-doped aluminum gallium indium arsenide (AlxGayIn1-x-yAs) nanowires, n-doped gallium indium phosphorus arsenide (GaxIn1-xPyAs1-y) nanowires, or n-doped indium gallium nitride (InxGa1-xN) nanowires. The n-layer and the i-layer of the heterojunction p-i-n junction include cadmium lead sulfide n-doped (CdxPb1-xS) nanowires, n-doped zinc cadmium mercury telluride (ZnxCdyHg1-x-yTe) nanowires, n-doped aluminum gallium indium arsenide (AlxGayIn1-x-y As) nanowires, n-doped gallium indium phosphorus arsenide (GaxIn1-xPyAs1-y) nanowires, or n-doped indium gallium nitride (InxGa1-xN) nanowires.    DESCRIPTION OF DRAWING(S) - The figure shows a schematic view of a LAMB solar cell structure.