Abstract: A solar collector tracking the sun through changes in the relative position between the sun and the earth. The collector may rotate about a single axis to follow the sun throughout the day. A second optional axis may compensate for the orientations of the sun in different seasons of the year. The energy received by the collector provides the motive power to effect its positional changes. A reflective concave surface with cylinderal symmetry and a cross-sectional parabolic configuration provides concentrate solar radiation at a transducer. Furnaces with an expandable fluid on either side of the focal line of the parabola connect to pistons to orient the collector. The parabola subtends an arc of about 41.degree. on either side of its center and, for an overall width of w, represents the locus of points equidistant between a straight line and a circle, tangent to the line, of radius r=kw/2. The constant k has a value dependent upon the intended latitude of the collector; varies between 0.611 and 0.