Optical performance of spherical reflecting elements for use with paraboloidal dish concentrators

While paraboloidal dishes have traditionally been used for high flux/high power solar concentration devices, the manufacture of multi-facet collectors has been complicated somewhat by the need to produce reflecting elements having different curvatures for different regions of the paraboloidal surface. This complication could be minimised by using identical spherical reflector sub-components mounted with a paraboloidal orientation on a space frame dish structure. This paper compares the optical performance and manufacturing feasibility of collectors having such a combination of surfaces.