Abstract: A method of concentrating directional radiant energy using reflective optics and receivers that convert that energy wherein the receivers are situated in the body of the reflector on risers parallel to the direction of radiant energy, each said riser bounded by at least one parabolic mirror lying closer and another lying farther from the energy source, where the focus or foci of said mirrors lie substantially in the direction faced by the receiver situated in said riser. The reflector geometries include ones in which the mirrors are parabolic cylinder sections and require only one-axis tacking to focus, and ones in which the mirrors are paraboloid sections and require two-axis tracking to focus sunlight.

Abstract: A system for collecting solar energy using a plurality of energy collection elements arranged in a planar array within a stationary base structure, each comprising: an energy capture unit with optical means of focusing directional sunlight parallel to its axis onto one or more sunlight-to-electricity converters within itself, and means of sensing divergence of its axis from the sun's direction; and an angular positioning unit that orients said capture unit about two nested axes by slidably mounting two arcuate tracks in opposed and perpendicular arcuate slots, a convex track within said energy capture unit and a concave track within said base structure, each said slot equipped with a drive apparatus that engages its respective track and moves the positioner along it. The invention provides methods for determining the shapes and arrangement of such elements so as to maximize aperture efficiency while preventing collisions of adjacent elements.