a fixed , linear , ground - based primary reflector having an extended curved sawtooth - contoured surface covered with a metalized polymeric reflecting material , reflects solar energy to a movably supported collector that is kept at the concentrated line focus of the reflector primary . the primary reflector may be constructed by a process utilizing well - known freeway paving machinery . the solar energy absorber is preferably a fluid - transporting pipe . efficient utilization leading to high temperatures from the reflected solar energy is obtained by cylindrical shaped secondary reflectors that direct off - angle energy to the absorber pipe . to obtain higher temperature levels , refocusing secondary reflectors , that cause a series of discrete spots of highly concentrated solar energy to fall on the fluid - transporting pipe , are utilized . a seriatim arrangement of cylindrical secondary reflector stages and spot - forming reflector stages produces a high temperature solar energy collection system of greater efficiency .