Described herein are solar reflectors which provide a low cost reflector construction that has a unique set of attributes: high solar reflectance, abrasion resistance, UV stability, mechanical integrity, and flexibility. The abrasion resistance is enabled through incorporation of an abrasion-resistant coating into a polymer film metal mirror construction. Methods of using the solar reflectors in solar concentrating applications are also provided.

A heat recovery system includes a compressor, a solar panel, and a first heat exchanger and a second heat exchanger in fluid connection to form a closed circuit. The compressor is configured to facilitate fluid movement in the fluid circuit between the solar panel, the first heat exchanger and the second heat exchanger. The solar panel includes a plurality of solar cells connected in parallel, and each solar cell includes a plurality of metal tubes for fluid to pass through. A temperature sensor is mounted within each of the solar cells and configured to measure temperature inside the respective solar cell. Each solar cell is connected to the circuit via a respective pressure valve, and the status of the pressure valve is configured to depend on the measurement of the temperature sensor in the respective solar cell.

A solar system is provided comprising a light receiving surface, a condensation subassembly, a water collection subassembly, and a cleaning subassembly. The expansion chamber of the condensation subassembly is thermally coupled to the light receiving surface and thermally insulated from the ambient such that expansion of compressed air in the expansion chamber, as controlled by the compressed air expansion valve, encourages humidity condensation on the light receiving surface by reducing the temperature of the light receiving surface. The water collection subassembly comprises a water collection vessel and water direction hardware positioned to direct condensed water on the light receiving surface to the water collection vessel. The cleaning subassembly comprises a water dispensing unit positioned to dispense water from the water collection vessel over the light receiving surface of the solar system.

An absorber pipe for solar collectors is provided. The absorber pipe includes a metal pipe for and a cladding pipe surrounding the metal pipe to form an annular space that can be evacuated. The absorber pipe can include a wall extending between the cladding pipe and the metal pipe for sealing the annular space and a retaining device for a getter material or a container filled with getter material or inert gas. The retaining device has a receiving section for receiving the getter material or the container. The retaining device is fastened to the wall. The absorber pipe can alternately include a getter material disposed in the annular space for binding free hydrogen present in the annular space and a reflector disposed in the annular space for reflecting radiation. The reflector has a housing with a support section for fastening and protecting the getter material from the radiation.

An absorber tube, especially for solar collectors in solar thermal power plants with at least one collector mirror, is provided. The absorber tube includes a metal tube for supplying and heating a heat transfer medium, a sheath tube surrounding the metal tube to form an annular space that can be evacuated, a wall extending through the sheath tube and the metal tube to seal the annular space, and a getter material binding free hydrogen in the annular space. The absorber tube has a temperature variation device that changes the temperature of the getter material and the wall.

A solar heat collecting device of the flat panel type, a process for its manufacture and parts thereof, made of extruded profiles in particular of aluminum or aluminum alloys. The device comprises a casing accommodating a heat collector assembly comprising a plurality of elongate extruded heat collector bodies, side by side, each having a tube co-axial with its axis of extrusion, flanked on each of its opposite sides integrally by an extruded web and further comprising a manifold at each end to which the respective tube ends are sealingly and communicatingly brazed. The edges of the adjoining webs of adjoining elongate bodies overlap slightly but are movable free of mechanical constraint or mutual attachment in relation to one another. Together the elongate bodies present the incoming solar radiation with a substantially plane uninterrupted area for absorption.

Provided are reflective thin film constructions including a reduced number of layers, which provides for increased solar-weighted hemispherical reflectance and durability. Reflective films include those comprising an ultraviolet absorbing abrasion resistant coating over a metal layer. Also provided are ultraviolet absorbing abrasion resistant coatings and methods for optimizing the ultraviolet absorption of an abrasion resistant coating. Reflective films disclosed herein are useful for solar reflecting, solar collecting, and solar concentrating applications, such as for the generation of electrical power.

The film mirror includes a resin substrate; a metal reflective layer; and a surface coating layer, a ratio of a number of fluorine atoms to a number of carbon atoms in a surface layer portion of the surface coating layer as expressed by F/C is 0.21 to 1.00 and the surface coating layer has a surface hardness of more than 100 N/mm.sup.2 and an elastic recovery rate of 60% or more. The film mirror has stain-proof properties, and scratch resistance so that the surface is resistant to scratches in collision with sandy dust and is also resistant to scratches upon cleaning with a brush.

Provided are reflective thin film constructions including a reduced number of layers, which provides for increased solar-weighted hemispherical reflectance and durability. Reflective films include those comprising an ultraviolet absorbing abrasion resistant coating over a metal layer. Also provided are ultraviolet absorbing abrasion resistant coatings and methods for optimizing the ultraviolet absorption of an abrasion resistant coating. Reflective films disclosed herein are useful for solar reflecting, solar collecting, and solar concentrating applications, such as for the generation of electrical power.

There is provided a pipe in a solar thermal power plant. The pipe includes an inner tube configured for carrying a heated heat transfer fluid, an outer tube surrounding the inner tube, wherein the space between the inner and outer tube is evacuated, and a getter restraint structure configured for maintaining getters in a predetermined position. The getter restraint structure is in contact with the outer tube and otherwise entirely free of contact with the inner tube and/or is in thermal isolation from the inner tube.