Solar power plant consisting of elongated modules whose longitudinal axes lie in a plane parallel to the direction of the sun rays to be converted. These modules are covered by lenses which refract sun rays impinging under an oblique angle downwards and which comprise two groups of refracting portions mirror-symmetrically arranged along the zenithal line which portions converge the refracted, downwardly directed sun beams into wedges of rays. These wedges of rays run twice per day in a vertical plane and during the remaining sunshine hours move within a narrow angular interval either towards the sun or away from the sun. This angular motion results in a vertical movement of the focal line so that the focal line coincides only twice per day with the height of the strip type photovoltaic cells. To force all wedges of rays to impinge evenly distributed onto the photovoltaic cell, a secondary lens is arranged above the photovoltaic cells. The light incident surface and shape of this lens produces the desired effect.

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