A solar cell assembly comprising a plurality of elongated solar cells, each elongated solar cell in the plurality of elongated solar cells comprising (i) an elongated conductive core configured as a first electrode, (ii) a semiconductor junction circumferentially disposed on the elongated conductive core, and (iii) a transparent conductive oxide layer disposed on the semiconductor junction. Each respective solar cell is bound to a first and second corresponding metal counter-electrode that lies in a groove running lengthwise on the respective elongated solar cell. The solar cell assembly further comprises a plurality of internal reflectors. Each respective internal reflector in the plurality of internal reflectors is configured between a first and second elongated solar cell in the plurality of elongated solar cells such that a portion of the solar light reflected from the respective internal reflector is reflected onto the corresponding first and second elongated cell.