For the production of the reflective surface of a solar parabolic trough concentrator in the form of a parabolic cylinder, a cost effective method is to use the elastic buckling of a flat sheet. However, the surface resulting in such a buckling is only a coarse approximation of the parabola, that is not precise enough for the need of a high quality concentrator. We propose a method to correct this defect of approximation by applying additional external forces on the buckled sheet. These external forces include an edge torsion force and a pressing force on the sheet. Optimal positions and parameters of these additional forces are computed for various cases, that give a result in theoretical maximal concentration ratio up to 171, so this method offers a very attractive approach for low cost and high efficiency solar energy solutions.
