Device for the concentration of solar radiation

A device for concentration of solar radiation in an absorber, comprising

• an inflatable concentrator cushion which comprises a cover film element comprising a light-permeable entry window for coupling in solar radiation and a reflector film for the concentration of the solar radiation in the absorber, the reflector film sub-dividing the concentrator cushion into at least two hollow spaces and having a curvature in an inflated state of the concentrator cushion,
• a pivoting apparatus by means of which the concentrator cushion is pivotable,
• a retaining apparatus mounted to the pivoting apparatus for retaining the concentrator cushion, and
• an adjusting device for adjusting the curvature of the reflector film of the concentrator cushion,
• wherein the retaining apparatus comprises a lower longitudinal member which extends in a longitudinal direction of the concentrator cushion and which is connected to a bottom film element of the concentrator cushion,
• wherein the adjusting device for adjusting the curvature of the reflector film comprises a tensioning element between the lower longitudinal member of the retaining apparatus and the reflector film, said tensioning element on one side being connected to the reflector film and on another side being secured to the lower longitudinal member of the retaining apparatus, wherein a normal distance between the lower longitudinal member and the reflector film can be changed by the tensioning element so as to adjust the tensile force transferred from the tensioning element to the reflector film.