Concentrating solar heat collector

A concentrating solar collector system of the reflecting type, comprising,

• (a) a series of parabolic-trough reflecting surfaces mounted one generally above the other, and mounted at an angle to collect radiation from about 30.degree. to 70.degree. above the horizon and reflect generally upright rays into a line focus,
• (b) target means superposed over each said reflecting surface arranged to be impinged on by said line focus,
• (c) said target means including heat storage means,
• (d) fluid conduit means extending through said storage means and in heat transfer contact therewith, and
• (e) means for insulating said heat storage means in the absence of solar radiation, said means for insulating includes a portion of each of said series of reflecting surfaces, said portion being a section of said reflecting surface, said section being movable to cover that portion of the target upon which the focused rays impinge, said reflecting surface section further includes an insulation backing attached to the rear surface of each section and a means along one edge thereof for pivotal movement of the section into a closed position over said target means.