Abstract: A solar collector utilizes an inflated tubular film which concentrates sunlight onto a solar receiver. The film incorporates refractive elements in a pattern which focuses light in one or two dimensions to create foci in the form of lines, spots, or other shapes. The film may be replaceable. The film may include layers of material to optimize optical, structural, thermal, and durability characteristics.

Abstract: The current surge indicator (10) has a ferromagnetic member (12) held about a conductor (15) with the ends of the member (12) in proximity and facing each other such that the ends are attracted to one another with a given force as current passes through the conductor (15). When the force exceeds a given threshold, a signal is created to help in locating where the current surge took place. The member may be spring loaded to open up, and the signal may be provided by the member being released by the current surge such that the member falls from the conductor. The conductor may be an anchor cable of an insulator or tower beam for a power transmission line.