Concentrating photovoltaics (CPV) often use Fresnel lenses, which are characterized by focal foreshortening and dispersion. These aberrations must be accounted for when designing Fresnel lenses for CPV applications. We discuss the dependence of the concentration limit of solar Fresnel lenses on dispersion in detail. For typical Fresnel lenses, dispersion creates a beam width in the order of the receiver size. Consequently, it is impossible to achieve a prescribed irradiance distribution on the target of refractive solar collectors with a concentration ratio above 500 suns, or for aspect ratios small or large.
展开▼
