Abstract: A plural axis sun tracking system, including a base, a spatial structure assembly, and a rotating system mounted on the base for rotating the spatial structure assembly, where the spatial structure assembly includes a frame having a lower portion at a first peripheral end of the spatial structure assembly and an upper portion at a second peripheral end of the spatial structure assembly, the lower portion being more proximal to the rotating system than the upper portion, and an anchoring location for anchoring the spatial structure assembly to the rotating system, the anchoring location located at the lower portion, where the mass of the frame increasingly recedes as the distance from the anchoring location towards the upper portion increases.

Abstract: An annulus assembly including a central fluid channel for flow of a central fluid therethrough, a circumferential fluid channel surrounding the central fluid channel, and a first thermal insulation layer intermediate the central fluid channel and the circumferential fluid channel, for direct fluid contact with the central fluid.

Abstract: A sun tracking system for tracking the sun in at least two axes, including a base, a rotating system mounted on the base, a spatial structure assembly having a lower portion at a first peripheral end thereof, and an upper portion at a second peripheral end thereof, the lower portion being more proximal to the base than the upper portion, and an anchoring location at the lower portion, and a torque box assembly at the anchoring location for resisting a torque applied to the spatial structure assembly.

Abstract: A solar concentrating system including a concentrator operative to track the Sun so as to concentrate incident sunlight on to a focal location, the concentrator including a support structure, and an array of concentrating reflectors mounted on the support structure, wherein at least one of the reflectors is formed with a reflective surface facing the Sun and configured as a concave surface such that the incident sunlight impinging on the reflective surface is reflected on to the focal location, the array of concentrating reflectors being mounted on the support structure in a Fresnel-like reflector arrangement thus defining the concentrator as a Fresnel reflector.